Crystal Growth and Atom Diffusion in (Cu)ZnTe/CdTe via Molecular Dynamics

Journal Article · 01 March 2018 · IEEE Journal of Photovoltaics

DOI: https://doi.org/10.1109/JPHOTOV.2017.2782565 · OSTI ID:1474058

Aguirre, Rodolfo  ^[1]; Chavez, Jose Juan  ^[2]; Li, Jiaojiao ^[3]; Zhou, Xiao Wang  ^[4]; Almeida, Sergio F.  ^[5]; Wolden, Colin ^[6]; Zubia, David  ^[1]

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1. Univ. of Texas, El Paso, TX (United States)
2. Univ. of Texas, El Paso, TX (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States)
3. Colorado School of Mines, Golden, CO (United States); REEL Solar, San Jose, CA (United States)
4. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
5. Univ. of Texas, El Paso, TX (United States); Univ. of California, Berkeley, CA (United States)
6. Colorado School of Mines, Golden, CO (United States)

Molecular dynamics (MD) simulations and experimental evaporation were applied to study the growth of evaporated (Cu)ZnTe on mono- and polycrystalline CdTe. The simulated structures show polytypism and polycrystallinity, including texturing and grain boundaries, diffusion, and other phenomena in excellent qualitative agreement with experimental atomic probe tomography, transmission electron microscope, and secondary ion mass spectrometry. Results show formation of Cu clusters in nonstoichiometric growths even at early stages of deposition. Results also show significantly faster diffusion along defected regions (uncorrelated CdTe grain boundaries) as compared with more highly crystalline areas (high-symmetry grain boundaries and pristine regions). Activation energies and pre-exponential factors of Cu, Zn, and Te diffusion were determined using simulation. The MD model captures crystal growth phenomena with a high degree of fidelity.

• Research Organization: Sandia National Laboratories (SNL-CA), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); National Science Foundation (NSF)
• Grant/Contract Number: AC04-94AL85000; EE0005958
• OSTI ID: 1474058
• Report Number(s): SAND--2018-10163J; 667923
• Journal Information: IEEE Journal of Photovoltaics, Journal Name: IEEE Journal of Photovoltaics Journal Issue: 2 Vol. 8; ISSN 2156-3381
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English