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  • Maintaining Atomically Smooth GaAs Surfaces After High-Temperature Processing for Precise Interdiffusion Analysis and Materials Engineering
Title: Maintaining Atomically Smooth GaAs Surfaces After High-Temperature Processing for Precise Interdiffusion Analysis and Materials Engineering
Arsenic’s high vapor pressure leads to thermal instability during hightemperature processing of GaAs, contributing to the performance degradation of subsequently fabricated devices. The resulting surface damage also obfuscates the exact quantitative characterization of the diffusion process, a critical step in device manufacturing. In this experiment, an encapsulant-and-sacrificial-layer procedure is employed to reduce arsenic sublimation and preserve a smooth surface. A capped GaAs/InGaAs/GaAs quantum well structure is subjected to rapid thermal annealing, and AFM, SEM, and EDS are used to compare the surface qualities of the postannealed encapsulated GaAs against the reference GaAs. For the encapsulated substrate, a smooth surface with an average root-mean-squared value of 6.5 Å is achieved after high-temperature processing. SIMS analysis is used to obtain the diffused indium atomic concentration profiles for a smooth and roughened GaAs surface and their corresponding diffusion parameters. The analysis demonstrates how precise diffusion parameter extraction requires preserving an atomically-smooth surface in semiconductor diffusion characterization.  more » « less
Award ID(s):
1808065
PAR ID:
10295323
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of vacuum science and technology
Volume:
Submitted
ISSN:
2166-2746
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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