Determination of carrier diffusion length in p- and n-type GaN

Size: px
Start display at page:

Download "Determination of carrier diffusion length in p- and n-type GaN"

Transcription

1 Determination of carrier diffusion length in p- and n-type GaN Shopan Hafiz* a, Sebastian Metzner b, Fan Zhang a, Morteza Monavarian a, Vitaliy Avrutin a, Hadis Morkoç a, Christopher Karbaum b, Frank Bertram b, Jürgen Christen b, Bernard Gil c, and Ümit Özgür a, a Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, Virginia 23284, USA b Institute of Experimental Physics, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany c CNRS-University Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F Montpellier, France ABSTRACT Diffusion lengths of photo-excited carriers along the c-direction were determined from photoluminescence (PL) measurements in p- and n-type GaN epitaxial layers grown on c-plane sapphire by metal-organic chemical vapor deposition. The investigated samples incorporate a 6 nm thick In 0.15 Ga 0.85 N active layer capped with either 500 nm p- GaN or 1300 nm n-gan. The top GaN layers were etched in steps and PL from the InGaN active region and the underlying layers was monitored as a function of the top GaN thickness upon photogeneration near the surface region by above bandgap excitation. Taking into consideration the absorption in the active and underlying layers, the diffusion lengths at 295 K and at 15 K were measured to be about 92 ± 7 nm and 68 ± 7 nm for Mg-doped p-type GaN and 432 ± 30 nm and 316 ± 30 nm for unintentionally doped n-type GaN, respectively. Cross-sectional cathodoluminescence line-scan measurement was performed on a separate sample and the diffusion length in n-type GaN was measured to be 280 nm. Keywords: Diffusion length, GaN, Photoluminescence, Cathodoluminescence. 1. INTRODUCTION Carrier diffusion length is an important physical parameter that directly affects the performance of electronic and optoelectronic semiconductor devices. Various experimental techniques such as electron beam induced current (EBIC), 1,2,3 junction based photocurrent, 4 surface photo-voltage spectroscopy 5 have been devised for its determination and a wide range of values ranging from 50 nm to 3.4 µm have been reported depending on the material quality, doping levels, and the techniques used. 1,2,3,4,5,6,7,8 In this study, we measured the diffusion length of the photogenerated carriers in n- and p- type GaN, along the c-direction using photoluminescence (PL) spectroscopy and compared the results with cathodoluminescence (CL) line-scan measurements. 2. EXPERIMENTAL PROCEDURE The samples used were c-plane 6 nm thick In 0.15 Ga 0.85 N double heterostructure (DH) active regions grown on a ~3.7 µmthick n-type GaN template on sapphire in a vertical low-pressure metalorganic chemical vapor deposition (MOCVD) system. A 60-nm Si-doped ( cm -3 ) In 0.01 Ga 0.99 N underlying layer was grown just beneath the active region for improving the quality of the overgrown layers. The structures were completed with either Mg-doped (doping concentration ~ cm -3 ) p-gan layer of 500-nm thickness or 1.30 µm thick unintentionally doped (doping concentration ~ cm -3 ) n-type GaN layer (Fig. 1). Hole concentration in p-gan was determined to be cm -3 from Hall measurements on a separate calibration sample. To mitigate the effect of Mg out-diffusion from p-gan on optical quality of the active region, a 20-nm thick In 0.01 Ga 0.99 N spacer layer was grown in between. In case of n-gan sample, the spacer layer thickness was 3 nm. Gallium Nitride Materials and Devices IX, edited by Jen-Inn Chyi, Yasushi Nanishi, Hadis Morkoç, Joachim Piprek, Euijoon Yoon, Hiroshi Fujioka, Proc. of SPIE Vol. 8986, 89862C 2014 SPIE CCC code: X/14/$18 doi: / Proc. of SPIE Vol C-1

2 Spacer layer - Active region - Underlying layers '-' - p-/n-gan (500nm/1.3µm) In0.01Ga0.99N (20nm/3nm) Ino.1sGao.ssN (ónm ) In0.01Ga0.99N (60nm) n-gan (^'3.7µm) Fig. 1. Cross-sectional schematic of the InGaN-based DH samples investigated. To achieve n- and p-type layers with different thickness, selective area inductively coupled plasma (ICP) etching was used in multiple steps. Etched thickness of the top layer was determined after each etching step using a surface profiler. PL measurements were carried out on regions with different p-gan/n-gan thicknesses using He-Cd laser (325 nm) excitation (excitation density of 4 kwcm -2 to 25 kwcm -2 ). As the absorption coefficient at the wavelength of the exciting laser is large, photogeneration of carriers takes place near the surface region of the sample and upon diffusion of carriers away from the surface the resulting PL from the active region, spacer layer and underlying n-gan is measured. The thicker the top layer, the less intense the PL from underlying layers. The PL intensity of the etched region was always compared with that from the corresponding un-etched reference region to minimize the effect of any variation across the sample. As the top GaN layer becomes thinner, PL contribution from photogenerated carriers due to direct absorption of light increases and becomes significant compared to the PL from diffused carriers. For CL measurement, a light emitting diode (LED) structure with an active region composed of four 3 nm-thick DHs separated by 3 nm In 0.06 Ga 0.94 N barrier (quad 3-nm DH) and 100 nm p-gan on top was used. 3. EXPERIMENTAL RESULT Fig. 2 shows the representative room temperature PL spectra for different top p-gan thicknesses when the detector side was optimized for n-gan luminescence. With decreasing p-gan thickness, PL intensity of underlying n-gan and spacer layer increase. Proc. of SPIE Vol C-2

3 PL intensity (arb. units) n-gan Sapcer layer p-gan thickness (nm) Active region Wavelength (nm) Fig. 2. Room temperature PL spectra of underlying n-gan and spacer layer for different p-gan thickness Fig. 3 shows the integrated PL intensity of underlying n-gan, spacer layer, and the active region plotted as a function of p-gan thickness at 295 K and at 15 K, taking into account the absorption in the active region and underlying layer using the absorption coefficients of InGaN and GaN calculated from their square root dependence on photon energy. 9 With increasing p-gan thickness, the normalized PL intensity from the Ldiff underlying n-gan layer exhibits an exponential decay, where x is the p-gan thickness and L diff is the diffusion length. The diffusion lengths in p-gan extracted from the fit are 92 ± 7 nm and 68 ± 7 nm at 295 K and 15 K, respectively. The same values within the error bars were obtained from the fits to the integrated PL intensities from the active region and the spacer layer. It should be noted that due to high Mg content, there is negligible near band edge emission from the p-gan layer. Moreover, it is noticeable that the active region emission is weaker than spacer layer and underlying n-gan emission. As the top p-gan layer is grown at a higher temperature (1000 C) compared to that for the active region (680 C) for a long period of time to achieve the desired thickness of 500 nm, the active region optical quality noticeably degrades as compared to conventional LED structure having thickness of the p-gan layer of only around 100 nm, possibly due to straindriven Indium diffusion. This effect is much higher for the active region because of its higher Indium composition compared to spacer layer. x e Proc. of SPIE Vol C-3

4 Normalized integrated PL intensity K underlying n-gan spacer layer active region 15K underlying n-gan p-gan thickness (nm) Fig. 3. Integrated PL from underlying GaN, spacer layer, and the active region at 15 and 295 K as a function of p-gan thickness. In case of n-gan capped sample, as the emission from the underlying n-gan layer cannot be differentiated, intensities of PL from the active region and underlying InGaN (only at 15 K) were monitored to determine the diffusion length. In Fig. 4 integrated active region PL intensity is plotted as a function of top n-gan thickness. Using an exponential decay fit as was done for p-gan, diffusion length in n-gan was found to be 432±30 nm at 295 K and 316±30 nm at 15 K. Underlying InGaN PL spectra could not be used for room temperature diffusion length estimation as emission from n- GaN was so strong that no distinct peak of InGaN emission was observed for a top n-gan thickness of 450 nm or more. Normalized integrated PL intensity K active region 15K active region underlying InGaN n-gan thickness (nm) Fig. 4. Integrated PL from the active region and spacer layer at 15 and 295 K as a function of p-gan thickness. Proc. of SPIE Vol C-4

5 Cross-sectional CL line scan was performed on quad DH sample at 5 K. Electron beam was focused on the underlying n- GaN and as the excitation gets closer to the active region, CL intensity starts increasing exponentially. Using the slope of this increase for exponential fitting, diffusion length in n-gan was measured to be 280 nm (Fig. 5) which is consistent with the PL measurement value CL Intensity (arb. units) normalized to n-gan active region (DH) underlying n-gan 0.1 λ DH =280 nm Linescan Position (µm) Fig. 5. Cross-sectional CL line-scan for quad DH at 5K The carrier diffusion lengths measured were found to be independent of the photogenerated carrier density within the range employed from cm -3 to cm -3 (calculated using radiative recombination coefficient, B = cm 3 s -1 ) 10 and the results for the highest excitation density are presented above. G. P. Yablonskii et al. 11 also reported little change in diffusion length for carrier density up to cm -3. Moreover, carrier diffusion length in p-gan is smaller than in n-gan, in agreement with previous studies. 2,3 This is expected because of a large concentration of Mg atoms required to achieve p-type doping due to the relatively deep Mg acceptor level. These substitutional Mg atoms act as traps for carriers and give rise to trap assisted recombination which eventually becomes the dominant recombination mechanism. The diffusion length has been reported 7 to decrease drastically from 950 nm to 220 nm with increasing Mg concentration from 4 x cm -3 to 3 x cm -3 for low dislocation densities of less than 10 8 cm -2. However, for relatively high dislocation density above 10 9 cm -2, diffusion length of electrons in p-gan was reported to be independent of Mg doping concentration. The decrease in diffusion length at low temperature in both n- and p-gan is due to the increased ionized impurity scattering which is dominant at low temperatures because, as the thermal velocity of the carriers reduces, the effect of long-range Coulomb interactions on their motion increases. This temperature dependence of diffusion length is also consistent with data available in literature, 1,12 although the specific values of diffusion lengths differ from those reported here due to different measurement techniques and varying layer quality. L. Chernyak et al. reported 1 the diffusion length in n-gan (electron concentration ~ cm -3 ) to be 1.25 µm at 300 K and 3 µm at 525 K while J. Y. Duboz et al. reported nm at 5 K and 320 nm at 80 K in unintentionally doped n-gan. 4. CONCLUSION In conclusion, carrier diffusion lengths in p-type and n-type GaN were determined by measuring the PL spectra of InGaN-based double heterostructures with different top n-gan and p-gan thickness and by the subsequent exponential fitting of the experimental data. As the photoexcited carrier concentration is in the same order of magnitude as the background carrier concentration, the estimated values of carrier diffusion lengths are ambipolar in nature. However, this method is also applicable for determination of minority carrier diffusion length by using lower photo-excitation density. Proc. of SPIE Vol C-5

6 The diffusion lengths at 295 K and at 15 K were measured to be 92 ± 7 nm and 68 ± 7 nm in p-type GaN and 432 ± 30 nm and 316 ± 30 nm in unintentionally doped n-type GaN, respectively and were independent of excitation density ranging from 4 kwcm -2 to 25 kwcm -2. Moreover, from cross-sectional CL line scan measurement, the diffusion length in n-type GaN was found to be 280 nm. Both of these methods of diffusion length estimation are simple, direct and require no contact formation unlike EBIC technique and yet give reliable values quite consistent with the literature. ACKNOWLEDGEMENTS The work at VCU was supported by NSF (grant number EPMD under direction of Dr. J. Zavada). The work at Magdeburg University is funded by the German Research Foundation DFG in the frame of the research unit FOR 957 PolarCoN. B. G. acknowledges support from GANEX (ANR-11-LABX-0014). REFERENCES [1] Chernyak, L., Osinsky, A., Temkin, H., Yang, J. W., Chen, Q. and Khan, M. A., Electron beam induced current measurements of minority carrier diffusion length in gallium nitride, Appl. Phys. Lett. 69, 2531 (1996) [2] Bandic, Z. Z., Bridger, P. M., Piquette, E. C. and McGill, T. C., Minority carrier diffusion length and lifetime in GaN, Appl. Phys. Lett. 72, 3166 (1998) [3] Bandic, Z. Z., Bridger, P. M., Piquette, E. C. and McGill, T. C., Electron diffusion length and lifetime in p -type GaN, Appl. Phys. Lett. 73, 3276 (1998) [4] Wee, D., Parish, G. and Nener, B., Investigation of the accuracy of the spectral photocurrent method for the determination of minority carrier diffusion length, J. Appl. Phys. 111, (2012) [5] Park, S. E., Kopanski, J. J., Kang, Y. S. and Robins, L. H., Surface photovoltage spectroscopy of minority carrier diffusion lengths in undoped and Si-doped GaN epitaxial films, Phys. Stat. Sol (c), 2, 2433 (2005) [6] Gonzalez, J. C., Bunker, K. L. and Russell, P. E. Minority-carrier diffusion length in a GaN-based light-emitting diode, Appl. Phys. Lett. 79, 1567 (2001) [7] Kumakura, K., Makimoto, T., Kobayashi, N., Hashizume, T., Fukui, T. and Hasegawa, H., Minority carrier diffusion length in GaN: Dislocation density and doping concentration dependence, Appl. Phys. Lett. 86, (2005) [8] Miyajima, T., Ozawa, M., Asatsuma, T., Kawai, H. and Ikeda, M., Minority carrier diffusion length in GaN and ZnSe, J. Cryst. Growth 189, 768 (1998) [9] Schubert, E. F., [Light-Emitting Diodes], 2 nd ed., Cambridge University Press, Cambridge, (2006) [10] Muth, J. F., Lee, J. H., Shmagin, I. K., Kolbas, R. M., Casey, H. C., Keller, B. P., Mishra, U. K. and DenBaars, S. P., Absorption coefficient, energy gap, exciton binding energy, and recombination lifetime of GaN obtained from transmission measurements, Appl. Phys. Lett. 71, 2572 (1997) [11] Yablonskii, G. P., Gurskii, A. L., Pavlovskii, V. N., Lutsenko, E. V., Zubialevich, V. Z., Shulga, T. S., Stognij, A. I., Kalisch, H., Szymakowski, A., Jansen, R. H., Alam, A., Schineller, B. and Heuken, M., Carrier diffusion length measured by optical method in GaN epilayers grown by MOCVD on sapphire substrates, J. Cryst. Growth 275, E1047 (2005) [12] Duboz, J. Y., Binet, F., Dolfi, D., Laurent, N., Scholz, F., Off, J., Sohmer, A., Briot, O., Gil, B., Diffusion length of photoexcited carriers in GaN, Mat. Sci. Eng. B 50, 289 (1997) Proc. of SPIE Vol C-6

High Performance AlGaN Heterostructure Field-Effect Transistors

High Performance AlGaN Heterostructure Field-Effect Transistors Kyma Inc. Contract ABR DTD 1/8/07; Prime: FA8650-06-C-5413 1 High Performance AlGaN Heterostructure Field-Effect Transistors Program Objectives The primary objectives of this program were to develop materials

More information

Characterization of 380 nm UV-LEDs grown on free-standing GaN by atmospheric-pressure metal-organic chemical vapor deposition

Characterization of 380 nm UV-LEDs grown on free-standing GaN by atmospheric-pressure metal-organic chemical vapor deposition Characterization of 380 nm UV-LEDs grown on free-standing GaN by atmospheric-pressure metal-organic chemical vapor deposition C. Y. Shieh 1, Z. Y. Li 2, H. C. Kuo 2, J. Y. Chang 1, G. C. Chi 1, 2 1 Department

More information

Supporting Information. AlN/h-BN Heterostructures for Mg Dopant-Free Deep Ultraviolet Photonics

Supporting Information. AlN/h-BN Heterostructures for Mg Dopant-Free Deep Ultraviolet Photonics Supporting Information AlN/h-BN Heterostructures for Mg Dopant-Free Deep Ultraviolet Photonics D. A. Laleyan 1,2, S. Zhao 1, S. Y. Woo 3, H. N. Tran 1, H. B. Le 1, T. Szkopek 1, H. Guo 4, G. A. Botton

More information

Pre-treatment of low temperature GaN buffer layer deposited on AlN Si substrate by hydride vapor phase epitaxy

Pre-treatment of low temperature GaN buffer layer deposited on AlN Si substrate by hydride vapor phase epitaxy Ž. Surface and Coatings Technology 131 000 465 469 Pre-treatment of low temperature GaN buffer layer deposited on AlN Si substrate by hydride vapor phase epitaxy Ha Jin Kim, Ho-Sun Paek, Ji-Beom Yoo Department

More information

ZnO thin film deposition on sapphire substrates by chemical vapor deposition

ZnO thin film deposition on sapphire substrates by chemical vapor deposition ZnO thin film deposition on sapphire substrates by chemical vapor deposition Zhuo Chen 1, T. Salagaj 2, C. Jensen 2, K. Strobl 2, Mim Nakarmi 1, and Kai Shum 1, a 1 Physics Department, Brooklyn College

More information

Free-standing a-plane GaN substrates grown by HVPE

Free-standing a-plane GaN substrates grown by HVPE Free-standing a-plane GaN substrates grown by HVPE Yin-Hao Wu*, Yen-Hsien Yeh, Kuei-Ming Chen, Yu-Jen Yang, and Wei-I Lee Department of Electrophysics, National Chiao Tung University, Hsinchu City 30010,

More information

Transmission Mode Photocathodes Covering the Spectral Range

Transmission Mode Photocathodes Covering the Spectral Range Transmission Mode Photocathodes Covering the Spectral Range 6/19/2002 New Developments in Photodetection 3 rd Beaune Conference June 17-21, 2002 Arlynn Smith, Keith Passmore, Roger Sillmon, Rudy Benz ITT

More information

The Blue Laser Diode. Shuji Nakamura Stephen Pear ton Gerhard Fasol. The Complete Story. Springer

The Blue Laser Diode. Shuji Nakamura Stephen Pear ton Gerhard Fasol. The Complete Story. Springer Shuji Nakamura Stephen Pear ton Gerhard Fasol The Blue Laser Diode The Complete Story Second Updated and Extended Edition With 256 Figures and 61 Tables Springer Contents 1. Introduction 1 1.1 LEDs and

More information

Comparison Study of Structural and Optical Properties of In x Ga 1-x N/GaN Quantum Wells with Different In Compositions

Comparison Study of Structural and Optical Properties of In x Ga 1-x N/GaN Quantum Wells with Different In Compositions Comparison Study of Structural and Optical Properties of In x Ga 1-x N/GaN Quantum Wells with Different In Compositions Yong-Hwan Kwon, G. H. Gainer, S. Bidnyk, Y. H. Cho, J. J. Song, M. Hansen 1, and

More information

The Optical Characteristics of Epitaxial Lateral and Vertical Overgrowth of GaN on Stripe-Patterned Si Substrate

The Optical Characteristics of Epitaxial Lateral and Vertical Overgrowth of GaN on Stripe-Patterned Si Substrate Journal of the Korean Physical Society, Vol. 50, No. 3, March 2007, pp. 771 775 The Optical Characteristics of Epitaxial Lateral and Vertical Overgrowth of GaN on Stripe-Patterned Si Substrate H. Y. Yeo,

More information

Erbium-doped a-plane GaN epilayers synthesized by metal-organic chemical vapor deposition

Erbium-doped a-plane GaN epilayers synthesized by metal-organic chemical vapor deposition Erbium-doped a-plane GaN epilayers synthesized by metal-organic chemical vapor deposition Talal Mohammed Al Tahtamouni, 1 Xiaozhang Du, 2 Jing Li, 2 Jingyu Lin 2 and Hongxing Jiang 2,* 1 Department of

More information

Introduction to Nitride Semiconductor Blue Lasers and Light Emitting Diodes

Introduction to Nitride Semiconductor Blue Lasers and Light Emitting Diodes Introduction to Nitride Semiconductor Blue Lasers and Light Emitting Diodes Edited by Shuji Nakamura and Shigefusa F. Chichibu London and New York Contents 1. Basics Physics and Materials Technology of

More information

Detrimental effects of dislocations II

Detrimental effects of dislocations II Detrimental effects of dislocations II Band diagram around a charged dislocation e - - - - - - - - Charged dislocation line Electrons get scattered by charged dislocations Mobility vs. sheet charge in

More information

Low temperature photoluminescence characteristics of Zn-doped InP grown by metalorganic chemical vapor deposition

Low temperature photoluminescence characteristics of Zn-doped InP grown by metalorganic chemical vapor deposition JOURNAL OF APPLIED PHYSICS VOLUME 83, NUMBER 4 15 FEBRUARY 1998 Low temperature photoluminescence characteristics of Zn-doped InP grown by metalorganic chemical vapor deposition Youngboo Moon, Sangkee

More information

2014 NOBEL LECTURE IN PHYSICS

2014 NOBEL LECTURE IN PHYSICS Background Story of the Invention of Efficient Blue InGaN Light Emitting Diodes SHUJI NAKAMURA SOLID STATE LIGHTING AND ENERGY ELECTRONICS CENTER MATERIALS AND ECE DEPARTMENTS UNIVERSITY OF CALIFORNIA,

More information

INTEGRATION OF N- AND P-CONTACTS TO GaN-BASED LIGHT EMITTING DIODES

INTEGRATION OF N- AND P-CONTACTS TO GaN-BASED LIGHT EMITTING DIODES International Journal of High Speed Electronics and Systems Vol. 20, No. 3 (2011) 521 525 World Scientific Publishing Company DOI: 10.1142/S0129156411006817 INTEGRATION OF N- AND P-CONTACTS TO GaN-BASED

More information

Gallium Nitride Based HEMT Devices

Gallium Nitride Based HEMT Devices Gallium Nitride Based HEMT Devices Keyan Zang SMA5111/6.772 Compound Semiconductor Materials and Devices May 14 th, 2003 Courtesy of Keyan Zang. Used with permission. Outline Introduction Device Structure

More information

Crystalline Silicon Solar Cells With Two Different Metals. Toshiyuki Sameshima*, Kazuya Kogure, and Masahiko Hasumi

Crystalline Silicon Solar Cells With Two Different Metals. Toshiyuki Sameshima*, Kazuya Kogure, and Masahiko Hasumi Crystalline Silicon Solar Cells With Two Different Metals Toshiyuki Sameshima*, Kazuya Kogure, and Masahiko Hasumi Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588,

More information

Cubic GaN Light Emitting Diode Grown by Metalorganic Vapor-Phase Epitaxy

Cubic GaN Light Emitting Diode Grown by Metalorganic Vapor-Phase Epitaxy TANAKA IEICE TRANS. and NAKADAIRA: ELECTRON., VOL. CUBIC E83-C, GaN LIGHT NO. 4 APRIL EMITTING 2000 DIODE 585 PAPER Special Issue on Blue Laser Diodes and Related Devices/Technologies Cubic GaN Light Emitting

More information

Characterisation of multiple carrier transport in indium nitride grown by molecular beam epitaxy

Characterisation of multiple carrier transport in indium nitride grown by molecular beam epitaxy phys. stat. sol. (c) 4, No. 7, 2423 2427 (2007) / DOI 10.1002/pssc.200674780 Characterisation of multiple carrier transport in indium nitride grown by molecular beam epitaxy Tamara B. Fehlberg 1, Gilberto

More information

doi: /

doi: / doi: 10.1063/1.366176 4f-shell configuration of Yb in InP studied by electron spin resonance T. Ishiyama a) and K. Murakami Institute of Materials Science, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba,

More information

Effect of thermal annealing on the surface, optical, and structural properties of p-type ZnSe thin films grown on GaAs (100) substrates

Effect of thermal annealing on the surface, optical, and structural properties of p-type ZnSe thin films grown on GaAs (100) substrates JOURNAL OF MATERIALS SCIENCE 39 (2 004)323 327 Effect of thermal annealing on the surface, optical, and structural properties of p-type ZnSe thin films grown on GaAs (100) substrates M. J. KIM, H. S. LEE,

More information

Effective Mg activation for p-type GaN in mixed gas ambient of oxygen and nitrogen Wei Lu 1,2, David Aplin 2, A. R. Clawson 2 and Paul K. L.

Effective Mg activation for p-type GaN in mixed gas ambient of oxygen and nitrogen Wei Lu 1,2, David Aplin 2, A. R. Clawson 2 and Paul K. L. Effective Mg activation for p-type GaN in mixed gas ambient of oxygen and nitrogen Wei Lu 1,2, David Aplin 2, A. R. Clawson 2 and Paul K. L. Yu 2 1 Zhejiang University, Zhejiang, PRC 2 Calit2, University

More information

Improving performance of InGaN LEDs on sapphire substrates

Improving performance of InGaN LEDs on sapphire substrates 80 Improving performance of InGaN LEDs on sapphire substrates Mike Cooke reports on research into semipolar growth, quantum well barrier composition and zinc oxide enhancements. Commercial indium gallium

More information

EFFECTS OF Si, Al 2 O 3 AND SiC SUBSTRATES ON THE CHARACTERISTICS OF DBRS STRUCTURE FOR GaN BASED LASER

EFFECTS OF Si, Al 2 O 3 AND SiC SUBSTRATES ON THE CHARACTERISTICS OF DBRS STRUCTURE FOR GaN BASED LASER Journal of Physical Science, Vol. 17(2), 151 159, 2006 151 EFFECTS OF Si, Al 2 O 3 AD SiC SUSTRATES O THE CHARACTERISTICS OF DRS STRUCTURE FOR Ga ASED LASER.M. Ahmed*, M.R. Hashim and Z. Hassan School

More information

Effects of growth pressure on erbium doped GaN infrared emitters synthesized by metal organic chemical vapor deposition

Effects of growth pressure on erbium doped GaN infrared emitters synthesized by metal organic chemical vapor deposition Effects of growth pressure on erbium doped GaN infrared emitters synthesized by metal organic chemical vapor deposition I-Wen Feng, 1,* Jing Li, 1 Jingyu Lin, 1 Hongxing Jiang, 1 and John Zavada 2 1 Department

More information

DEEP TRAPS SPECTRA IN UNDOPED GAN FILMS GROWN BY HYDRIDE VAPOR PHASE EPITAXY UNDER VARIOUS CONDITIONS

DEEP TRAPS SPECTRA IN UNDOPED GAN FILMS GROWN BY HYDRIDE VAPOR PHASE EPITAXY UNDER VARIOUS CONDITIONS American Journal of Applied Sciences 11 (9): 1714-1721, 2014 ISSN: 1546-9239 2014 A.Y. Polyakov et al., This open access article is distributed under a Creative Commons Attribution (CC-BY) 3.0 license

More information

Super widegap nitride semiconductors for UV lasers

Super widegap nitride semiconductors for UV lasers (Registration number: 2001MB047) Super widegap nitride semiconductors for UV lasers Research Coordinator Fernando A. Ponce Research Team Members Hiroshi Amano David Cherns Isamu Akasaki Arizona State University:

More information

Supporting Online Material for

Supporting Online Material for www.sciencemag.org/cgi/content/full/327/5961/60/dc1 Supporting Online Material for Polarization-Induced Hole Doping in Wide Band-Gap Uniaxial Semiconductor Heterostructures John Simon, Vladimir Protasenko,

More information

Current Gain Dependence on Subcollector and Etch-Stop Doping in InGaP/GaAs HBTs

Current Gain Dependence on Subcollector and Etch-Stop Doping in InGaP/GaAs HBTs IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 48, NO. 5, MAY 2001 835 Current Gain Dependence on Subcollector and Etch-Stop Doping in InGaP/GaAs HBTs Theodore Chung, Seth R. Bank, John Epple, and Kuang-Chien

More information

InGaN/GaN Light Emitting Diodes With a p-down Structure

InGaN/GaN Light Emitting Diodes With a p-down Structure IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 49, NO. 8, AUGUST 2002 1361 InGaN/GaN Light Emitting Diodes With a p-down Structure Y. K. Su, Senior Member, IEEE, S. J. Chang, Chih-Hsin Ko, J. F. Chen, Member,

More information

Excitation and pressure effects on photoluminescence from silicon-based light emitting diode material

Excitation and pressure effects on photoluminescence from silicon-based light emitting diode material Excitation and pressure effects on photoluminescence from silicon-based light emitting diode material Y. Ishibashi 1,3, A. Nagata 1, T. Kobayashi 1 *, A.D. Prins 2, S. Sasahara 3, J. Nakahara 3, M.A. Lourenco

More information

MOVPE growth of GaN and LED on (1 1 1) MgAl

MOVPE growth of GaN and LED on (1 1 1) MgAl Journal of Crystal Growth 189/190 (1998) 197 201 MOVPE growth of GaN and LED on (1 1 1) Shukun Duan *, Xuegong Teng, Yutian Wang, Gaohua Li, Hongxing Jiang, Peide Han, Da-Cheng Lu National Integrated Optoelectronics

More information

INGAN BASED LIGHT EMITTING DIODE AND LASER DIODE THE PRESENT AND THE FUTURE

INGAN BASED LIGHT EMITTING DIODE AND LASER DIODE THE PRESENT AND THE FUTURE 52 INGAN BASED LIGHT EMITTING DIODE AND LASER DIODE THE PRESENT AND THE FUTURE Nasser N.Morgan a,b and Ye Zhizhen a a State key Laboratory of Silicon materials, Zhejiang University, Hangzhou, China b Faculty

More information

Defense Technical Information Center Compilation Part Notice

Defense Technical Information Center Compilation Part Notice UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP012180 TITLE: Growth of Highly Oriented ZnO Nanorods by Chemical Vapor Deposition DISTRIBUTION: Approved for public release,

More information

Optoelectronic characterization of Au/Ni/n-AlGaN photodiodes after annealing at different temperatures

Optoelectronic characterization of Au/Ni/n-AlGaN photodiodes after annealing at different temperatures Optoelectronic characterization of Au/Ni/n-AlGaN photodiodes after annealing at different temperatures PNM Ngoepe *, WE Meyer, M Diale, FD Auret, L van Schalkwyk Department of Physics, University of Pretoria,

More information

ARTICLE IN PRESS. Journal of Crystal Growth

ARTICLE IN PRESS. Journal of Crystal Growth Journal of Crystal Growth 312 (2010) 680 684 Contents lists available at ScienceDirect Journal of Crystal Growth journal homepage: www.elsevier.com/locate/jcrysgro Effect of growth conditions on Eu 3+

More information

OPTICAL MODE PATTERN STUDY OF GAN BASED LEDS WITH AND WITHOUT NANOSCALE TOP GRATING

OPTICAL MODE PATTERN STUDY OF GAN BASED LEDS WITH AND WITHOUT NANOSCALE TOP GRATING OPTICAL MODE PATTERN STUDY OF GAN BASED LEDS WITH AND WITHOUT NANOSCALE TOP GRATING by Greg Chavoor Senior Project ELECTRICAL ENGINEERING DEPARTMENT California Polytechnic State University San Luis Obispo

More information

Optimization of a Chlorine-Based Deep Vertical Etch of GaN Demonstrating Low Damage and Low Roughness

Optimization of a Chlorine-Based Deep Vertical Etch of GaN Demonstrating Low Damage and Low Roughness Optimization of a Chlorine-Based Deep Vertical Etch of GaN Demonstrating Low Damage and Low Roughness Running title: Low Damage Cl2/Ar Deep Vertical GaN Etch Running Authors: Tahhan et al. Maher Tahhan

More information

MOCVD Technology for LED

MOCVD Technology for LED MOCVD Technology for LED Prof. Dr.-Ing. Michael Heuken Vice President Corporate Research and Development AIXTRON AG, Fon: +49 (241) 8909-154, Fax: +49 (241) 8909-149, Email: M.Heuken@AIXTRON.com RWTH Aachen,

More information

Research Article Thermal Characteristics of InGaN/GaN Flip-Chip Light Emitting Diodes with Diamond-Like Carbon Heat-Spreading Layers

Research Article Thermal Characteristics of InGaN/GaN Flip-Chip Light Emitting Diodes with Diamond-Like Carbon Heat-Spreading Layers International Photoenergy, Article ID 829284, 5 pages http://dx.doi.org/1.1155/214/829284 Research Article Thermal Characteristics of InGaN/GaN Flip-Chip Light Emitting Diodes with Diamond-Like Carbon

More information

Rare Earth Doping of Silicon-Rich Silicon Oxide for Silicon-Based Optoelectronic Applications

Rare Earth Doping of Silicon-Rich Silicon Oxide for Silicon-Based Optoelectronic Applications Journal of the Korean Physical Society, Vol. 39, December 2001, pp. S78 S82 Rare Earth Doping of Silicon-Rich Silicon Oxide for Silicon-Based Optoelectronic Applications Se-Young Seo, Hak-Seung Han and

More information

High Transmittance Ti doped ITO Transparent Conducting Layer Applying to UV-LED. Y. H. Lin and C. Y. Liu

High Transmittance Ti doped ITO Transparent Conducting Layer Applying to UV-LED. Y. H. Lin and C. Y. Liu High Transmittance Ti doped ITO Transparent Conducting Layer Applying to UV-LED Y. H. Lin and C. Y. Liu Department of Chemical Engineering and Materials Engineering, National Central University, Jhongli,

More information

Structural and optical properties of AlInN and AlGaInN on GaN grown by metalorganic vapor phase epitaxy

Structural and optical properties of AlInN and AlGaInN on GaN grown by metalorganic vapor phase epitaxy Journal of Crystal Growth 195 (1998) 309 313 Structural and optical properties of AlInN and AlGaInN on GaN grown by metalorganic vapor phase epitaxy Shigeo Yamaguchi*, Michihiko Kariya, Shugo Nitta, Hisaki

More information

OUTLINE. Preparation of III Nitride thin 6/10/2010

OUTLINE. Preparation of III Nitride thin 6/10/2010 Preparation of III Nitride thin films for LEDs Huaxiang Shen Supervisor: Dr. Adrian Kitai 1 2 Two kinds of EL devices Light emitting diodes Powder EL and thin film EL http://en.wikipedia.org/wiki/file:pnjunction

More information

MAGNETIC AND OPTICAL PROPERTIES OF MN DOPED GAN

MAGNETIC AND OPTICAL PROPERTIES OF MN DOPED GAN MAGNETIC AND OPTICAL PROPERTIES OF MN DOPED GAN F. E. Arkun, N. A. El-Masry Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 7695, USA M. J. Reed

More information

Highly selective photoenhanced wet etching of GaN for defect investigation and device fabrication

Highly selective photoenhanced wet etching of GaN for defect investigation and device fabrication Mat. Res. Soc. Symp. Proc. Vol. 639 2001 Materials Research Society Highly selective photoenhanced wet etching of GaN for defect investigation and device fabrication P. Visconti 1, M. A. Reshchikov, K.

More information

Materials Aspects of GaAs and InP Based Structures

Materials Aspects of GaAs and InP Based Structures AT&T Materials Aspects of GaAs and InP Based Structures V. Swaminathan AT&T Belt Laboratories Breinigsvil/e, Pennsylvania A. T. Macrander Argonne National Laboratory Argonne, Illinois m Prentice Hall,

More information

STRUCTURE AND MORPHOLOGY OF INDIUM NITRIDE THIN FILMS GROWN BY PLASMA ASSISTED PLD: THE IMPACT OF NITROGEN FLOW AND SUBSTRATE TEMPERATURE

STRUCTURE AND MORPHOLOGY OF INDIUM NITRIDE THIN FILMS GROWN BY PLASMA ASSISTED PLD: THE IMPACT OF NITROGEN FLOW AND SUBSTRATE TEMPERATURE Romanian Reports in Physics, Vol. 65, No. 1, P. 213 218, 2013 PLASMA PHYSICS STRUCTURE AND MORPHOLOGY OF INDIUM NITRIDE THIN FILMS GROWN BY PLASMA ASSISTED PLD: THE IMPACT OF NITROGEN FLOW AND SUBSTRATE

More information

Impurity free vacancy disordering of InGaAs quantum dots

Impurity free vacancy disordering of InGaAs quantum dots JOURNAL OF APPLIED PHYSICS VOLUME 96, NUMBER 12 15 DECEMBER 2004 Impurity free vacancy disordering of InGaAs quantum dots P. Lever, H. H. Tan, and C. Jagadish Department of Electronic Materials Engineering,

More information

High reflectivity and thermal-stability Cr-based Reflectors and. n-type Ohmic Contact for GaN-based flip-chip light-emitting.

High reflectivity and thermal-stability Cr-based Reflectors and. n-type Ohmic Contact for GaN-based flip-chip light-emitting. High reflectivity and thermal-stability Cr-based Reflectors and n-type Ohmic Contact for GaN-based flip-chip light-emitting diodes Kuang-Po Hsueh, a * Kuo-Chun Chiang, a Charles J. Wang, b and Yue-Ming

More information

AlGaN/GaN HFETs on 100 mm Silicon Substrates for Commercial Wireless Applications

AlGaN/GaN HFETs on 100 mm Silicon Substrates for Commercial Wireless Applications Materials Technology Using Si as a substrate material for GaN based devices enables a variety of applications and manufacturing technologies. The 100 mm Si substrate platform allows use of larger state-of-the-art

More information

Effect of grain boundaries on photovoltaic properties of PX-GaAs films

Effect of grain boundaries on photovoltaic properties of PX-GaAs films Indian Journal of Pure & Applied Physics Vol. 48, August 2010, pp. 575-580 Effect of grain boundaries on photovoltaic properties of PX-GaAs films M K Sharma & D P Joshi* Principal, Govt Sr Sec School Kolar,

More information

Red luminescence from Si quantum dots embedded in SiO x films grown with controlled stoichiometry

Red luminescence from Si quantum dots embedded in SiO x films grown with controlled stoichiometry Red luminescence from Si quantum dots embedded in films grown with controlled stoichiometry Zhitao Kang, Brannon Arnold, Christopher Summers, Brent Wagner Georgia Institute of Technology, Atlanta, GA 30332

More information

Er 3+ Photoluminescence Excitation Spectra in Erbium-Doped Epitaxial Silicon Structures

Er 3+ Photoluminescence Excitation Spectra in Erbium-Doped Epitaxial Silicon Structures Physics of the Solid State, Vol. 46, No. 1, 24, pp. 97 1. Translated from Fizika Tverdogo Tela, Vol. 46, No. 1, 24, pp. 98 11. Original Russian Text Copyright 24 by Andreev, Krasil nik, Kryzhkov, Yablonskiœ,

More information

MOCVD technology in research, development and mass production. H. Juergensen. AIXTRON AG, Kackertstr , D Aachen, Germany

MOCVD technology in research, development and mass production. H. Juergensen. AIXTRON AG, Kackertstr , D Aachen, Germany MOCVD technology in research, development and mass production H. Juergensen AIXTRON AG, Kackertstr. 15-17, D-52072 Aachen, Germany e-mail: info@aixtron.com, phone: +49-241-8909-0, fax: +49-241-8909-40

More information

The effect of rapid thermal annealing to device performance of InGaAs/AlGaAs quantum well laser diodes

The effect of rapid thermal annealing to device performance of InGaAs/AlGaAs quantum well laser diodes Indian Journal of Pure & Applied Physics Vol. 55, May 2017, pp. 333-338 The effect of rapid thermal annealing to device performance of InGaAs/AlGaAs quantum well laser diodes P L Gareso a*, M Buda b, H

More information

ABSORPTION COEFFICIENT AND REFRACTIVE INDEX OF GaN, AlN AND AlGaN ALLOYS

ABSORPTION COEFFICIENT AND REFRACTIVE INDEX OF GaN, AlN AND AlGaN ALLOYS ABSORPTION COEFFICIENT AND REFRACTIVE INDEX OF GaN, AlN AND AlGaN ALLOYS J. F. MUTH **, J. D. BROWN *, M. A. L. JOHNSON *, ZHONGHAI YU *, R. M. KOLBAS **, J. W. COOK, JR *. and J. F. SCHETZINA * * Department

More information

LEEN Characterization of Ohmic Contacts and Device Processing on AlGaN/GaN for HEMT Applications. Student Researcher: Gregg H.

LEEN Characterization of Ohmic Contacts and Device Processing on AlGaN/GaN for HEMT Applications. Student Researcher: Gregg H. LEEN Characterization of Ohmic Contacts and Device Processing on AlGaN/GaN for HEMT Applications Student Researcher: Gregg H. Jessen Advisor: Dr. Leonard J. Brillson The Ohio State University Department

More information

Taiyo Nippon Sanso. Advancing UV LEDs and power devices. The precarious promise of 5G. Evaluating the III-V MOSFET. Smart options for the infrared LED

Taiyo Nippon Sanso. Advancing UV LEDs and power devices. The precarious promise of 5G. Evaluating the III-V MOSFET. Smart options for the infrared LED Volume 22 Issue 3 April / May 2016 @compoundsemi www.compoundsemiconductor.net The precarious promise of 5G Evaluating the III-V MOSFET Smart options for the infrared LED Taiyo Nippon Sanso Advancing UV

More information

Studies on Si-doped AlGaN Epilayers

Studies on Si-doped AlGaN Epilayers Studies on Si-doped AlGaN Epilayers 47 Studies on Si-doped AlGaN Epilayers Kamran Forghani Growth optimization of Si doped AlGaN epilayers with 20%, 30% and 45%Al content grown on AlGaN-sapphire by MOVPE

More information

Suitable Semiconductor Properties for Photoelectrochemistry Evaluated using Nitrides

Suitable Semiconductor Properties for Photoelectrochemistry Evaluated using Nitrides Univ. Jaume-I Castellon de la Plana, Spain, 2012.09.18 1 Suitable Semiconductor Properties for Photoelectrochemistry Evaluated using Nitrides Katsushi Fujii Global Solar and Initiative : GS + I, the University

More information

CHAPTER 4 LED LIGHT EMITTING DIODE

CHAPTER 4 LED LIGHT EMITTING DIODE CHAPTER 4 LED LIGHT EMITTING DIODE 1 PART II LIGHT EMITTING DIODE LED are semiconductor p-n junctions that under forward bias conditions can emit What is LED? radiation by electroluminescence in the UV,

More information

High-efficiency light-emitting diode with air voids embedded in lateral epitaxially overgrown GaN using a metal mask

High-efficiency light-emitting diode with air voids embedded in lateral epitaxially overgrown GaN using a metal mask High-efficiency light-emitting diode with air voids embedded in lateral epitaxially overgrown GaN using a metal mask Chu-Young Cho, 1 Min-Ki Kwon, 3 Il-Kyu Park, 4 Sang-Hyun Hong, 1 Jae-Joon Kim, 2 Seong-Eun

More information

Structural Analysis in Low-V-defect Blue and Green GaInN/GaN Light Emitting Diodes

Structural Analysis in Low-V-defect Blue and Green GaInN/GaN Light Emitting Diodes Mater. Res. Soc. Symp. Proc. Vol. 1040 2008 Materials Research Society 1040-Q03-02 Structural Analysis in Low-V-defect Blue and Green GaInN/GaN Light Emitting Diodes Mingwei Zhu 1,2, Theeradetch Detchprohm

More information

Research Article Characteristics of GaN/InGaN Double-Heterostructure Photovoltaic Cells

Research Article Characteristics of GaN/InGaN Double-Heterostructure Photovoltaic Cells Photoenergy Volume 212, Article ID 26174, 5 pages doi:1.1155/212/26174 Research Article Characteristics of /In Double-Heterostructure Photovoltaic Cells Ming-Hsien Wu, 1 Sheng-Po Chang, 1 Shoou-Jinn Chang,

More information

Chapter 6. AlGaAs/GaAs/GaAs Wafer-fused HBTs

Chapter 6. AlGaAs/GaAs/GaAs Wafer-fused HBTs Chapter 6. AlGaAs/GaAs/GaAs Wafer-fused HBTs 6.1. Overview Previous chapters described an AlGaAs-GaAs-GaN HBT, in which an epitaxially grown AlGaAs-GaAs emitter-base was wafer-fused to a GaN collector.

More information

1. Introduction. 2. COMD Mechanisms. COMD Behavior of Semiconductor Laser Diodes. Ulrich Martin

1. Introduction. 2. COMD Mechanisms. COMD Behavior of Semiconductor Laser Diodes. Ulrich Martin COMD Behavior of Semiconductor Laser Diodes 39 COMD Behavior of Semiconductor Laser Diodes Ulrich Martin The lifetime of semiconductor laser diodes is reduced by facet degradation and catastrophical optical

More information

M. Hasumi, J. Takenezawa, Y. Kanda, T. Nagao and T. Sameshima

M. Hasumi, J. Takenezawa, Y. Kanda, T. Nagao and T. Sameshima Proceedings of 6th Thin Film Materials & Devices Meeting November 2-3, 2009, Kyoto, Japan http://www.tfmd.jp/ Characterization of SiO x /Si Interface Properties by Photo Induced Carrier Microwave Absorption

More information

I. GaAs Material Properties

I. GaAs Material Properties I. GaAs Material Properties S. Kayali GaAs is a III V compound semiconductor composed of the element gallium (Ga) from column III and the element arsenic (As) from column V of the periodic table of the

More information

A CRITICAL COMPARISON BETWEEN MOVPE AND MBE GROWTH OF III-V NITRIDE SEMICONDUCTOR MATERIALS FOR OPTO-ELECTRONIC DEVICE APPLICATIONS

A CRITICAL COMPARISON BETWEEN MOVPE AND MBE GROWTH OF III-V NITRIDE SEMICONDUCTOR MATERIALS FOR OPTO-ELECTRONIC DEVICE APPLICATIONS A CRITICAL COMPARISON BETWEEN MOVPE AND MBE GROWTH OF III-V NITRIDE SEMICONDUCTOR MATERIALS FOR OPTO-ELECTRONIC DEVICE APPLICATIONS M.A.L. JOHNSON,**, ZHONGHAI YU *, J.D. BROWN *, F.A. KOECK *, N.A. EL-MASRY

More information

An advantage of thin-film silicon solar cells is that they can be deposited on glass substrates and flexible substrates.

An advantage of thin-film silicon solar cells is that they can be deposited on glass substrates and flexible substrates. ET3034TUx - 5.2.1 - Thin film silicon PV technology 1 Last week we have discussed the dominant PV technology in the current market, the PV technology based on c-si wafers. Now we will discuss a different

More information

Process Development for Porous Silicon Light-Emitting Devices

Process Development for Porous Silicon Light-Emitting Devices Process Development for Porous Silicon Light-mitting Devices Jason Benz Advisor: K. Hirschman Rochester Institute of Technology Rochester, NY 14623 Absfract - The primary focus of this project was to continue

More information

FINE STRUCTURE OF THE 3.42 ev EMISSION BAND IN GaN

FINE STRUCTURE OF THE 3.42 ev EMISSION BAND IN GaN In Gallium Nitride and Related Materials, Eds. F. Ponce, R.D. Dupuis, S. Nakamura, and J.A. Edmond, Proc. Mat. Res. Soc. Symp. 395, 571 (1996). FINE STRUCTURE OF THE 3.42 ev EMISSION BAND IN GaN S. FISCHER*,

More information

The Effects of Sapphire Substrates Processes to the LED Efficiency

The Effects of Sapphire Substrates Processes to the LED Efficiency The Effects of Sapphire Substrates Processes to the LED Efficiency Hua Yang*, Yu Chen, Libin Wang, Xiaoyan Yi, Jingmei Fan, Zhiqiang Liu, Fuhua Yang, Liangchen Wang, Guohong Wang, Yiping Zeng, Jinmin Li

More information

Electronic properties of GaNAs alloy

Electronic properties of GaNAs alloy Electronic properties of GaNAs alloy Sumith Doluweera Department of Physics University of Cincinnati Cincinnati, Ohio 45221 March 08 2002 Abstract A brief review on the present knowledge of the electronic

More information

InGaN quantum dot based LED for white light emitting

InGaN quantum dot based LED for white light emitting Emerging Photonics 2014 InGaN quantum dot based LED for white light emitting Luo Yi, Wang Lai, Hao Zhibiao, Han Yanjun, and Li Hongtao Tsinghua National Laboratory for Information Science and Technology,

More information

The Effect of Heat Treatment on Ni/Au Ohmic Contacts to p-type GaN

The Effect of Heat Treatment on Ni/Au Ohmic Contacts to p-type GaN Li-Chien Chen et al.: The Effect of Heat Treatment on Ni/Au Ohmic Contacts 773 phys. stat. sol. (a) 176, 773 (1999) Subject classification: 73.40.Cg; S7.14 The Effect of Heat Treatment on Ni/Au Ohmic Contacts

More information

III III a IIOI OlD IIO OlD 110 II II III lulu II OI IIi

III III a IIOI OlD IIO OlD 110 II II III lulu II OI IIi (19) United States III III a IIOI OlD IIO 1101 100 1101 OlD 110 II II III lulu II OI IIi US 20060270076A1 (12) Patent Application Publication (10) Pub. No.: US 2006/0270076 Al Imer et al. (43) Pub. Date:

More information

Low-cost, deterministic quasi-periodic photonic structures for light trapping in thin film silicon solar cells

Low-cost, deterministic quasi-periodic photonic structures for light trapping in thin film silicon solar cells Low-cost, deterministic quasi-periodic photonic structures for light trapping in thin film silicon solar cells The MIT Faculty has made this article openly available. Please share how this access benefits

More information

Advantages of Employing the Freestanding GaN Substrates with Low Dislocation Density for White Light-Emitting Diodes

Advantages of Employing the Freestanding GaN Substrates with Low Dislocation Density for White Light-Emitting Diodes ELECTRONICS Advantages of Employing the Freestanding GaN Substrates with Low Dislocation Density for White Light-Emitting Diodes Yusuke Yoshizumi*, Takahisa Yoshida, Takashi KYono, masaki ueno and Takao

More information

Supplementary Information (SI)

Supplementary Information (SI) Supplementary Information (SI) Horizontally assembled green InGaN nanorod LEDs: scalable polarized surface emitting LEDs using electric-field assisted assembly Hoo Keun Park a, Seong Woong Yoon a, Yun

More information

Introduction Joachim Piprek

Introduction Joachim Piprek 3 1 Introduction Joachim Piprek 1.1 A Brief History Considerable efforts to fabricate nitride devices began more than three decades ago. In 1971, Pankove et al. reported the first GaN-based lightemitting

More information

LBIC investigations of the lifetime degradation by extended defects in multicrystalline solar silicon

LBIC investigations of the lifetime degradation by extended defects in multicrystalline solar silicon LBIC investigations of the lifetime degradation by extended defects in multicrystalline solar silicon Markus Rinio 1, Hans Joachim Möller 1 and Martina Werner 2, 1 Institute for Experimental Physics, TU

More information

The Effect of Annealing Heat Treatment on Structural and Optical Properties of Ce-doped ZnO Thin Films

The Effect of Annealing Heat Treatment on Structural and Optical Properties of Ce-doped ZnO Thin Films 4th International Conference on Computer, Mechatronics, Control and Electronic Engineering (ICCMCEE 2015) The Effect of Annealing Heat Treatment on Structural and Optical Properties of Ce-doped Thin Films

More information

Plasmonic Photovoltaics

Plasmonic Photovoltaics Plasmonic Photovoltaics Investigators Harry A. Atwater, Howard Hughes Professor and Professor of Applied Physics and Materials Science, California Institute of Technology Krista Langeland, Ph.D. student,

More information

Compositional Profile of Graded VCSEL DBRs

Compositional Profile of Graded VCSEL DBRs Compositional Profile of Graded VCSEL DBRs 3 Compositional Profile of Graded VCSEL DBRs Fernando Rinaldi and Dietmar Wahl The compositional profile of graded distributed Bragg reflectors (DBRs) in vertical-cavity

More information

The Effect of Growth Conditions on The Optical and Structural Properties of InGaN/GaN MQW LED Structures Grown by MOCVD

The Effect of Growth Conditions on The Optical and Structural Properties of InGaN/GaN MQW LED Structures Grown by MOCVD Gazi University Journal of Science GU J Sci 27(4):115-111 (214) The Effect of Growth Conditions on The Optical and Structural Properties of InGaN/GaN MQW LED Structures Grown by MOCVD S.Ş. ÇETĐN 1,2,,

More information

Blueshift of optical band gap in ZnO thin films grown by metal-organic chemical-vapor deposition

Blueshift of optical band gap in ZnO thin films grown by metal-organic chemical-vapor deposition JOURNAL OF APPLIED PHYSICS 98, 013505 2005 Blueshift of optical band gap in ZnO thin films grown by metal-organic chemical-vapor deposition S. T. Tan, B. J. Chen, X. W. Sun, a and W. J. Fan School of Electrical

More information

INVESTIGATION OF PHOTOVOLTAIC PROPERTIES of p-inse/n-cds HETEROJUNCTION SOLAR CELLS

INVESTIGATION OF PHOTOVOLTAIC PROPERTIES of p-inse/n-cds HETEROJUNCTION SOLAR CELLS Journal of Ovonic Research Vol. 1, No. 3, May - June 214, p. 67-73 INVESTIGATION OF PHOTOVOLTAIC PROPERTIES of p-inse/n-cds HETEROJUNCTION SOLAR CELLS K. YILMAZ * Pamukkale University, Science and Arts

More information

Molecular Beam Epitaxial Growth of AlN/GaN Multiple Quantum Wells

Molecular Beam Epitaxial Growth of AlN/GaN Multiple Quantum Wells Mat. Res. Soc. Symp. Proc. Vol. 743 2003 Materials Research Society L6.2.1 Molecular Beam Epitaxial Growth of AlN/GaN Multiple Quantum Wells Hong Wu, William J. Schaff, and Goutam Koley School of Electrical

More information

( 01) ß-Gallium Oxide substrate for high quality GaN materials

( 01) ß-Gallium Oxide substrate for high quality GaN materials Invited Paper ( 01) ß-Gallium Oxide substrate for high quality GaN materials I.S.Roqan * and M. M. Muhammed King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering

More information

Germanium and silicon photonics

Germanium and silicon photonics 76 Technical focus: III-Vs on silicon optoelectronics Germanium and silicon photonics Mike Cooke reports on recent research using germanium to enable infrared light-emitting devices to be created on silicon

More information

Improve the performance of MOCVD grown GaN-on-Si HEMT structure

Improve the performance of MOCVD grown GaN-on-Si HEMT structure Improve the performance of MOCVD grown GaN-on-Si HEMT structure Dr. Xiaoqing Xu Stanford Nanofabrication Facility Abstract The SNF installed a new metalorganic chemical vapor deposition (MOCVD) system

More information

Correlation Between Energy Gap and Defect Formation of Al Doped Zinc Oxide on Carbon Doped Silicon Oxide

Correlation Between Energy Gap and Defect Formation of Al Doped Zinc Oxide on Carbon Doped Silicon Oxide TRANSACTIONS ON ELECTRICAL AND ELECTRONIC MATERIALS Vol. 15, No. 4, pp. 207-212, August 25, 2014 Regular Paper pissn: 1229-7607 eissn: 2092-7592 DOI: http://dx.doi.org/10.4313/teem.2014.15.4.207 Correlation

More information

Investigation of high voltage induced damage of GaN grown on Si substrate by terahertz nano-imaging and spectroscopy 1.

Investigation of high voltage induced damage of GaN grown on Si substrate by terahertz nano-imaging and spectroscopy 1. Investigation of high voltage induced damage of GaN grown on Si substrate by terahertz nano-imaging and spectroscopy 1 Introduction May 18, 2017 Anis Rahman, PhD Applied Research & Photonics, Inc. ( ARP

More information

ISSN: ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT) Volume 3, Issue 6, December 2013

ISSN: ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT) Volume 3, Issue 6, December 2013 ISSN: 2277-3754 Fabrication and Characterization of Flip-Chip Power Light Emitting Diode with Backside Reflector Ping-Yu Kuei, Wen-Yu Kuo, Liann-Be Chang, Tung-Wuu Huang, Ming-Jer Jeng, Chun-Te Wu, Sung-Cheng

More information

Development of indium-rich InGaN epilayers for integrated tandem solar cells

Development of indium-rich InGaN epilayers for integrated tandem solar cells http://journals.cambridge.org/action/displayabstract?frompage=online&aid=8846343 Development of indium-rich InGaN epilayers for integrated tandem solar cells A. G. Melton 1, B. Kucukgok 1, B-Z. Wang 1,2,

More information

Red InGaP light-emitting diodes epitaxially grown on engineered Ge-on-Si substrates

Red InGaP light-emitting diodes epitaxially grown on engineered Ge-on-Si substrates Red InGaP light-emitting diodes epitaxially grown on engineered Ge-on-Si substrates The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters.

More information

DISTRIBUTION A: Distribution approved for public release.

DISTRIBUTION A: Distribution approved for public release. AFRL-OSR-VA-TR-2014-0375 Novel Substrates for Photodetectors David J. Smith ARIZONA STATE UNIVERSITY 12/23/2014 Final Report DISTRIBUTION A: Distribution approved for public release. Air Force Research

More information