Defect analysis and performance evaluation of p-type epitaxial GaAs layer on Ge substrate for GaAs/Ge based advanced device

Goutam Kumar Dalapati, Vignesh Suresh, Sandipan Chakraborty, Chandreswar Mahata, Yi Ren, Thirumaleshawara Bhat, Sudhiranjan Tripathy, Taeyoon Lee, Lakshmi Kanta Bera, Dongzhi Chi

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The structural defects and formation of native oxides during thermal treatment on p-type epitaxial-GaAs/Ge have been investigated using spectroscopic measurements and electrical characterization. The performance of epi-GaAs based device depends on the interface quality between epi-GaAs and gate oxide and structural quality of the epi-GaAs layer. P-type epitaxial-GaAs was grown on Ge substrate using MOCVD technique at 675°C. Defective surface native oxides of arsenic and gallium oxides are observed for as-grown epi-GaAs layer. The arsenic oxide significantly reduced after thermal treatment as seen from XPS observations. The structural defects at surface enhanced after thermal treatment which is clearly probed by micro-Raman spectroscopy. Atomic layer deposited (ALD) Al2O3 significantly improved the interface properties after thermal treatment compared with bare epi-GaAs layer. Even though, the interface trap defect density slightly higher for p-type epi-GaAs MOS capacitor compared with bulk p-type GaAs devices, high frequency-dispersion in epi-GaAs based devices observed. This is mainly governs through the formation of p-i-n junction diode in the epi-GaAs layer on Ge substrates.

Original languageEnglish
Pages (from-to)517-524
Number of pages8
JournalAdvanced Materials Letters
Volume7
Issue number7
DOIs
Publication statusPublished - 2016 Jul 1

All Science Journal Classification (ASJC) codes

  • Materials Science(all)

Fingerprint Dive into the research topics of 'Defect analysis and performance evaluation of p-type epitaxial GaAs layer on Ge substrate for GaAs/Ge based advanced device'. Together they form a unique fingerprint.

  • Cite this

    Dalapati, G. K., Suresh, V., Chakraborty, S., Mahata, C., Ren, Y., Bhat, T., Tripathy, S., Lee, T., Bera, L. K., & Chi, D. (2016). Defect analysis and performance evaluation of p-type epitaxial GaAs layer on Ge substrate for GaAs/Ge based advanced device. Advanced Materials Letters, 7(7), 517-524. https://doi.org/10.5185/amlett.2016.6439