Defect Analysis of MBE Reactor-Grown HgCdTe on Si, GaAs, GaSb, and CZT Substrates Through the TNL-Epigrow Simulator

• Published in: Journal of electronic materials Vol. 53; no. 10; pp. 5803 - 5812
• Main Authors: Saxena, P. K., Srivastava, P., Srivastava, A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-10-2024; Springer Nature B.V
• Subjects: Adsorption; Cadmium zinc tellurides; Characterization and Evaluation of Materials; Chemical vapor deposition; Chemistry and Materials Science; Crystal defects; Defects; Diffusion layers; Dislocation density; Electronics and Microelectronics; Epitaxial growth; Equilibrium; Gallium antimonides; Gallium arsenide; Instrumentation; Lattice parameters; Lattice vacancies; Materials Science; Mercury cadmium tellurides; Molecular beam epitaxy; Molecular structure; Morphology; Optical and Electronic Materials; Organic chemicals; Reactors; Real time; Sensors; Silicon substrates; Solid State Physics; Surface roughness; Topical Collection: 2023 U.S. Workshop on Physics and Chemistry of II-VI Materials; U.S. Workshop on the Physics and Chemistry of II-VI Materials 2023; TNL-EpiGrow; MBE; dislocation; vacancies; simulation; atomic; HgCdTe (MCT); epitaxy
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-024-11082-0

This paper systematically reviews the progress on the HgCdTe (MCT) material deposition via molecular-beam epitaxy (MBE) and previously reported atomistic approaches used to model the MCT epitaxy. The structure design and fabrication of the infrared (IR) detection systems require highly crystalline MCT films. The state-of-the-art of the MBE growth processes of Hg
1−
x
Cd
x
Te films over Si, GaAs, GaSb, and CdZnTe substrates are reported here from an atomistic simulation perspective. The most advanced in-house-developed kinetic Monte Carlo (kMC) technique, coupled with the geometry of the MBE reactor (implemented in the TNL-EpiGrow
TM
simulator) is exploited to reproduce real-time MBE experiments. The ability to track each atom involved in the adsorption, diffusion, and desorption processes over the lattice provides deeper insights. The ability to map various defects quantitatively and qualitatively during the growth process in a layer-by-layer and island mode helps to provide a proper understanding of their formation. The TNL-EpiGrow
TM
simulator provides an innovative and cost-effective solution for the epitaxial growth processes associated with MBE, CVD, and MOCVD reactors for most semiconductors. The types of defects, their position over the lattice, layer-by-layer strain, surface roughness, lattice parameters are easily extractable and provide an unmatched solution. However, it is very difficult to realize similar solutions through sophisticated instruments. Si, GaAs, GaSb, and CdZnTe substrates have been used to reproduce the MBE process of Hg
1−
x
Cd
x
Te (
x
≈ 0.55). The vacancies and dislocation densities are reported here to characterize the cases of MCT epitaxy on the four different substrates. The growth rates of CdTe and MCT have been benchmarked against the experimental data (Pacuski et al. in Cryst Growth Des 17(6):2987, 2017; Wijewamauriya et al. in Appl Phys Lett 51(24):2025, 1987). The output results revealed that CdZnTe is the most attractive substrate choice but, due to its technological challenges, GaSb can replace it and is the most suitable option for the growth of Hg
1−
x
Cd
x
Te as compared to Si and GaAs substrates under similar conditions. The results reported here also support the experimental findings (Gu et al. in J Cryst Growth 468:216, 2017). The dislocations and vacancies generated in the GaSb substrate are comparable to those in the CdZnTe substrate.