& Electron Beam Induced Processes and their Applicability to Mask Repair Hans W.P. Koops (1), Volker Boegli (1), Klaus Edinger (1), Johannes Bihr (2), Jens Greiser (2), (1) NaWoTec GmbH Rossdorf Germany Koops@nawotec.de, Tel: +49 6154 8038-0, Fax: +49 6154 8038-80 (2) LEO Elektronenmikroskopie GmbH Oberkochen Germany greiser@leo.de, Tel: +49 7364 944757, Fax: +49 7364 944670 1 ISMT/Selete Antwerpen 8.9.2002
Outline Principle of 3-D-Lithography Why e-beam mask repair 70nm mask repair tool strategy Specifications Experimental tool Performance capability Alpha-tool Capability Deposition results and AIMS characterization Key engineering / development challenges Extendibility and roadmap Conclusion 2 ISMT / SELETE Antwerpen 08.09.2002 &
Principle of 3-Dimensional Lithography using Electron-Beam Induced Deposition and Etching Organometallic precursor Nozzle Electron beam Residual gas Evaporating radicals Deposit Adsorbed molecules Sample Electron Beam induced reactions of adsorbed molecules by electrons of high energy Power density: 60 MW/cm 2 -> Deposition of fragments -> Evaporation of reaction products 3 ISMT / SELETE Antwerpen 08.09.2002 &
1 µm 4 ISMT / SELETE Antwerpen 08.09.2002 &
Why E-Beam Mask Repair? Ion beams generate unavoidable substrate damage by ion implantation and mixing No solution for chemical reactions below 80 nm is demonstrated Electron beams avoid substrate damage and allow high resolution Courtesy: Ted Liang: 157 nm Workshop Dana Point. 2001 Only the LEO Gemini optics meets the high resolution specs 5 ISMT / SELETE Antwerpen 08.09.2002 &
Operating Principle of the Objective Lens Magnetic lens Aberration Coefficients [mm] 25 20 15 Spherical 10 5 Chromatic 0 0 5 10 15 20 25 30 Beam Energy [KeV] Electrostatic lens Compound magnetic/electrostatic objective lens has smaller aberrations than pure electrostatic or magnetic lens Usually the objective lens aberrations are constants. Due to the GEMINI operation principle lens aberrations are coefficients which show a dramatic reduction at low beam energy 6 ISMT / SELETE Antwerpen 08.09.2002 &
Clean Mask Repair using E- Beam Chemistry Base Tool: LEO high performance GEMINI 1500 VP FE-SEM 100 V to 30 kv, 1pA to 20 na, Schottky field emitter column with low Cs and Cc, in-lens detector, 6 mask /8 wafer, interferometer controlled stage Gas supply system Multi-Jet: NaWoTec design and production, interfaced to the e-beam platform Deposition and etching: NaWoTec beam control system Active drift compensation Proprietory recipes Custom designed specialized solutions 7 ISMT / SELETE Antwerpen 08.09.2002 &
Co-operation: Photo Mask Repair Tool PMRT NaWoTec LEO FE-SEM 1500 VP Gas supply system Beam control Active drift compensation Image processing Defect compensation Repair process control Application laboratory Continued development Computer Interface to SEM VP-SEM 6 100 V 30 kv Motorstage Laser interferometer Airlock Hot FE-gun 1 pa - 20 na Beam blanking Service of PMRT Marketing & Sales 8 ISMT / SELETE Antwerpen 08.09.2002 &
E-beam Mask Repair Experimental System Based on the LEO 1530 VP FE-SEM with NaWoTec s 4-Channel Multi-Jet software controlled gas supply system, pattern generator, control and GUI Installed at NaWoTec s Application Lab 9 ISMT / SELETE Antwerpen 08.09.2002 &
High Resolution Patterning with Deposition Platinum deposition with the experimental- PMRT on Cr demonstrates: 20 nm features < 4 nm edge roughness < 10 nm drift/min highly accurate pattern generation 10 ISMT / SELETE Antwerpen 08.09.2002 &
Deposition with 5 the kv,17 Experimental 5kV pa17pa System Pt/C deposition using LEO 1530 VP FSEM and NaWoTec Multi-Jet 1 kv 17 pa 500 V 13 Picture taken at 30 tilt Experimental Pt-supply: 0.068 µm³/nc @ 1 kv 500 nm x 500 nm, 80 nm thickness deposited in 30 sec 300 V 12 p 11 ISMT / SELETE Antwerpen 08.09.2002 &
E-beam Mask Repair Alpha-Tool LEO base system: 1500 VP FE-SEM GEMINI column VP vacuum system 8 wafer, 6 mask Airlock Laser interferometer NaWoTec integrates: 4-channel Multi-Jet software controlled gas supply system Pattern generator Control and GUI Defect cruising Repair procedures Drift compensation 12 ISMT / SELETE Antwerpen 08.09.2002 &
Deposition of Pt/C bars on quartz between chromium lines 1 µm Deposition time for 1 µm x 1 µm, 80 nm thick is 2 minutes, Aims @ 248 nm shows good process control for 3 sets of structures NA = 0,54 Rel. Intensity 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0-12 -10-8 -6-4 -2 0 2 4 6 8 X-Position [µm] 13 ISMT / SELETE Antwerpen 08.09.2002 & set1x.aim set2x.aim set3x.aim
Deposition of Pt/C bars on quartz Comparison @248 nm of attennuation of structures of equal size, NA = 0,54 a15.aim ref.aim Pt/C-deposit and chrome Square, 1.2 kv, 50pA 1.1 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 a15.aim ref.aim y 14 ISMT / SELETE Antwerpen 08.09.2002 &
Demonstration of TaN etching Etching of TaN is performed using XeF 2 at 1 kv, 17 pa Etch depth 70 nm Etch time for 1 µm x 1 µm 70 nm deep is 5 sec 15 ISMT / SELETE Antwerpen 08.09.2002 &
Demonstration of stencil mask repair with Pt/C- 3-D-deposition 100 nm Deposition of Pt/C bridges across Si-membrane gap 16 ISMT / SELETE Antwerpen 08.09.2002 &
E-beam Mask Repair Top 3 Challenges Chrome etching Compensation of charging effects Avoid contamination at low kv 17 ISMT / SELETE Antwerpen 08.09.2002 &
NaWoTec & LEO PMRT- Development Roadmap Year 2002 2003 Quarter Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Exp. PMRT 1530/Multi-Jet α-tool PMRT (1500VP/Multi-Jet) β-tool (PMRT) β-tool: factory acceptance 10 12 month after order 18 ISMT / SELETE Antwerpen 08.09.2002 &
Beta- and Production Tool Key Characteristics Beta tool 1500 VP based semi-automatic operation open defect repair closed defect repair 6 mask / 8 wafer chamber laser interferometer stage meets SEMI S2/S8 specs Production tool enhancements fully automatic open and closed defect repair 9 mask chamber (12 if req.) autoloader available Q4/2003 available Q4/2005 Systems can be upgraded with new deposition/etch recipes Tool meets the repair requirements of the 70 nm device node and is extendible to 50 nm and potentially 35 nm nodes 19 ISMT / SELETE Antwerpen 08.09.2002 &
Conclusion NaWoTec and LEO jointly develop an electron beam based Photo Mask Repair Tool Initial marketing and support jointly by NaWoTec and LEO Worldwide sales and services by LEO Application laboratory at NaWoTec Continued develompment by NaWoTec β- tool will meet the 70 nm node requirements So far demonstrated: High resolution Pt/C deposition High resolution etching of quartz, SiO 2, SiC and TaN 20 ISMT / SELETE Antwerpen 08.09.2002 &
Discussion foils 21 ISMT / SELETE Antwerpen 08.09.2002 &
Company Overview: NaWoTec GmbH Nano World Technologies Founded as a Spin-Off from T-Nova, Deutsche Telekom AG 25 full time employees, 11 temporary employees Technical advisors from international companies and universities Office and laboratory building 13000 sqft Clean room laboratory 1800 sqft class 1000 Clean room applications, assembly 1000 sqft class 100 3 Experimental SEM s with Multi-Jet for deposition and etching 1 α-tool LEO 1500VP based, 8 Chamber, Multi-Jet 2 Experimental nanolithography systems 22 ISMT / SELETE Antwerpen 08.09.2002 &
NaWoTec Mission and Visions Development and production of a system for nanolithography with electron-beam induced reactions for photo- and NGL- mask repair for the semiconductor industry Development and production of novel and innovative components for : Bio-nano-technology Electronics Field emitter applications Medical applications Optics and telecommunications 23 ISMT / SELETE Antwerpen 08.09.2002 &
Carl Zeiss Semiconductor Manufacturing Technology AG CEO: Dr. D. Kurz Legal Structure since October 2001 Carl Zeiss Carl Zeiss S-M-T AG CEO: Dr. H. Gerlinger CFO: D. Schoch. Employees: 1600 LEO Group CEO: Dr. D. Stenkamp CFO: R. Yoder LEO GmbH (GER) Employees: 360 LEO Inc. (USA) LEO Ltd. (UK) LEO S.A. (F) 24 ISMT / SELETE Antwerpen 08.09.2002 &
Carl Zeiss S-M-T AG Product Portfolio for Key IC Manufacturing Lithography Mask Inspection & E-beam Repair CZ MES LEO Group Wafer Inspection, Review and Failure Analysis 25 ISMT / SELETE Antwerpen 08.09.2002 &
Total Solutions for Masks (CZ SMT AG) NaWoTec & LEO CZ MES GmbH E-beam Mask Repair Tool In co-operation with AIMS fab 26 ISMT / SELETE Antwerpen 08.09.2002 &
Electron Optics of the LEO 1500 VP Beam path with no intermediate cross over Electromagnetic aperture changer Field lens In-lens SE-detector Beam booster Magnetic lens Scan coils Electrostatic lens Specimen U Ex U L U 0 Highly stable thermal FEG <0.5%/h variation Low beam noise1% Cross over free beam path No significant Boersch effect, high depth of field. Low aberrations C c and C s Superb image resolution throughout the whole beam energy range, particularly down to 100eV. High resistance to ambient magnetic stray fields. 27 ISMT / SELETE Antwerpen 08.09.2002 &
Schematic of the Photo Mask repair Tool LEO GEMINI 28 ISMT / SELETE Antwerpen 08.09.2002 &