In-Situ Thin Film Diffraction at SSRL

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1 In-Situ Thin Film Diffraction at SSRL Capabilities and Example Studies Dr. Christopher J. Tassone 6 th Annual SSRL Scattering Workshop

2 Why In-situ Know your Beamlines 10-2, 7-2, 2-1 and 11-3 In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing Spin coating Outline

3 Outline Why In-situ Know your Beamlines 10-1, 7-2, 2-1 and 11-3 Examples of In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing Spin coating

4 Why In-Situ? Traditionally we make thin films, bring them to the beamline and measure their end-state properties We want to know more! Film formation Kinetics How and why do complicated nanostructures form Post-processing screening How can thin film post-processing techniques develop specific nanostructures Rapid screening of thin film deposition techniques Lets take advantage of all those photons!

5 Outline Why In-situ Beamlines 10-1, 7-2, 2-1 and 11-3 Examples of In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing Spin coating

6 Get to know your beamlines! Beamline 11-3 Thin film powerhouse Beamline 7-2 High temporal resolution and high flux Beamline 10-2 Brightest line at SSRL Beamline 2-1 X-ray Reflectivity

7 Get to know your beamlines! Beamline 11-3 Grazing incidence x- ray diffraction geometry 12.7 KeV photons Mar 345 image plate detector Its gigantic 70 sec readout Heat samples in-situ to 300 C Oversubscribed

8 Beamline 7-2 Get to know your beamlines! 6-c diffractometer Facilitates large array of experiments High flux 5 x ph/s Dynamic Energy Range 5-16 KeV Multiple Detectors Pilatus 100K In the process of getting a 2M Vortex point detector In-situ heating to 900 C

9 Get to know your beamlines! Beamline 10-2 Brightest line at SSRL 1 x ph/s Multiple Detectors Pilatus 100K Vortex Point Detector 4-c diffractometer Dynamic Energy Range KeV In-situ heating to 900 C Very Oversubscribed

10 Get to know your beamlines! Beamline 2-1 Multiple experimental setups X-ray reflectivity High Resolution X-ray Diffraction Sealed Chamber Capable of: In-situ solvent swelling/annealing Feed throughs for in-operando electrical characterization Dynamic Energy Range 4-14 KeV Vortex Point Detector

11 Outline Why In-situ Know your Beamlines 10-1, 7-2, 2-1 and 11-3 Examples of In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing Spin coating

12 Bulk Heterjunctions (BHJ) as a Model System -

13 Bulk Heterjunctions (BHJ) as a Model System Morphology is very sensitive to changes in processing conditions A precise control of the degree of phase segregation must be maintained in every film Thermal and Solvent annealing have been employed to control morphology

14 Bulk Heterjunctions (BHJ) as a Model System intermixed phase Interface composition phase segregation molecular ordering, orientation organic/organic and organic/inorganic

15 In-situ Thermal Annealing Currently performed at beamline 11-3 Temporal resolution limited to 70 seconds Exposure times system dependent Facilitates: Screening of optimal thermal annealing temperature Mechanistic studies of epitaxial molecular alignment during phase transitions

16 In-situ Thermal Annealing 2q = scattering angle Q = (4π/λ) sin θ Heating Stage Capable of Heating to 300 C Programmable Ramp Cycle High Throughput Temperature Studies

17 P3HT structure: P3HT-PCBM: polymer structure (h00): slow (00l): fast (0k0): fast bad - OPV Q z Q xy or Q good - OPV

18 Temperature Neat P3HT In-situ annealing 230 C Time SSRL/LCLS Users Meeting, October (010)2010 peak (200) peak

19 Neat P3HT in-situ annealing below Tm (204 C): coherence length increases & surface roughens, but no crystallite reorientation => existing crystallites grow larger & lattice disorder decreases above Tm: crystallite reorientation & coherence length increases => nucleation at substrate interface

20 Temperature Neat PCBM in-situ annealing 300 C Time at 148 C, PCBM crystallizes, PCBM SSRL/LCLS Users Meeting, October 2010 Tm at 290 C crystallization

21 Neat PCBM in-situ annealing PCBM crystalline intensity Crystallization above 155 ºC o 1-dimensional crystallite growth o high density heterogeneous substrate nucleation Crystallization at 150 ºC o combination of 1, 2, and 3 dimensional crystallite growth o Low density heterogeneous substrate nucleation Films annealed above 142 ºC show crystallization of PCBM Glass transition of PCBM ~ 148 ºC PCBM melts at 290 ºC

22 P3HT-PCBM annealing 1:1 P3HT:PCBM blend: in-situ heating to 220ºC 180ºCcooling 160ºC 60ºC 25ºC 210ºC 220ºC 200ºC 190ºC 170ºC 140ºC 120ºC 100ºC 80ºC heating heating cooling

23 P3HT-PCBM annealing P3HT:PC 60 BM blends: P3HT reorientation (Tm) & PCBM crystallization blends same features as pure components but transitions shifted: P3HT Tm decreases with increasing PCBM fraction; PCBM is similar to plasticizer PCBM crystallization temperature decreases with increasing P3HT P3HT inhibits PCBM crystallization (1:1 & 3:1) P3HT reorientation PCBM cold crystallization P3HT 205ºC - 3:1 201ºC - 1:1 195ºC - 1:3 Not clearly seen ºC PCBM - 148ºC poly(3-hexylselenophene) (P3HS) Lilliu et al, Macromol. RC 32, 1454 (2011).

24 In-situ Annealing Summary 1. Pure P3HT Tm and crystallite reorientation 2. Pure PCBM cold crystallization at T 150C 3. P3HT-PCBM blends: 1:3 -> 1:1 -> 3:1 Influence of blend on P3HT Tm & PCBM crystallization Explain why the common c annealing creates ideal film morphology Verploegen et al., Adv. Func. Mater. 20, 3519 (2010)

25 Outline Why In-situ Know your Beamlines 10-1, 7-2, 2-1 and 11-3 Examples of In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing

26 In-situ Solvent Annealing Currently performed at beamline 11-3 Temporal resolution limited to 70 seconds Exposure times system dependent Solvent annealing will be tested at beamline 7-2 this summer This would enable ½ s temporal resolution Faciliates: rapid solvent screening Reorganization, crystallization kinetics

27 In-situ Solvent Annealing Goals: Use GIXS to monitor solvent effect on film crystallization/reorientation Can we use in-situ GIXS to rapidly screen solvent annealing conditions Can we elucidate the mechanism by which solvent annealing alters thin film properties

28 In-situ Solvent Annealing How does the molecular structure effect opto-electronic properties? Can we determine the optimal flow rate, solvent annealing time etc? How does choice of solvent effect molecular confirmation, orientation?

29 Kinetics Through In-situ S.A. Crystallization Kinetics observable through solvent scattering

30 Rapid Solvent Annealing Screening Solvent Screening through in-situ S.A. Solvent choice, flow rate, carrier gas selection, etc Kinetic information for all 6 solvents gathered in two 8 hour shifts!

31 Outline Why In-situ Know your Beamlines 10-1, 7-2, 2-1 and 11-3 Examples of In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing

32 In-situ Water Swelling Performed at beamline 2-1 Goals Use XRR to track film swelling during exposure to water vapor Is water swelling reversible? Can we track surface roughness? Gandhiraman, R.P et. al. J. Mater. Chem. SSRL/LCLS (20) Users Meeting, October 2010

33 In-situ Water Swelling l N 2 l H 2 O +N 2 l N 2 l Gandhiraman, R.P et. al. J. Mater. Chem. SSRL/LCLS (20) Users Meeting, October 2010

34 Outline Why In-situ Know your Beamlines 10-1, 7-2, 1-4 and 11-3 Examples of In-situ techniques Thermal annealing Solvent annealing Water Swelling Future directions Printing at the beamline Rapid thermal annealing

35 Summary SSRL offers a potential to study thin film properties in-situ Deposition kinetics Post-processing mechanisms Rapid screening of parameter space In-operando device physics Expanding capabilities will enable higher temporal resolution, and expanded experimental capabilities What are your in-situ needs?

36 Mike Toney Eric Verploegen Kristin Schmidt Ram Gandhiraman Funding Acknowledgements Center for Advanced Molecular Photovoltaics (CAMP) Department of Energy: Office of Basic Energy Sciences(DOE BES) Global Climate and Energy Climate (GCEP) Stanford Linear Accelerator Center (SLAC)