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JOURNAL OF SYNTHETIC CRYSTALS ›› 2024, Vol. 53 ›› Issue (2): 252-257.

• Research Articles • Previous Articles     Next Articles

Study on vdW Epitaxy Mechanism and Stress Modulation of Large-Size GaN Microwave Material

LI Chuanhao1,2, LI Zhonghui1,2, PENG Daqing1,2, ZHANG Dongguo1,2, YANG Qiankun1,2, LUO Weike1,2   

  1. 1. Science and Technology on Monolithic Integrated Circuits and Modules Laboratory, Nanjing Electronic Devices Institute, Nanjing 210016, China;
    2. CETC Key Laboratory of Carbon-based Electronics, Nanjing 210016, China
  • Received:2023-06-13 Online:2024-02-15 Published:2024-02-04

Abstract: Based on metal organic chemical vapor deposition (MOCVD), growth mechanism and stress modulation of van der Waals (vdW) heteroepitaxial GaN microwave material were studied with few-layer BN as an interlayer on 4-inch sapphire substrates. The influence of AlN nucleate process on growth mechanism of GaN buffer layer and its correlation with crystalline quality, stress, and electrical properties were discussed. A stress modulation scheme based on AlN/AlGaN composite nucleation process is proposed, achieving stress well in control for large-size vdW heteroepitaxy firstly. The as-grown GaN microwave material possesses a wafer bow of +20.4 μm, fullwidth at half maximum of GaN (002)/(102) peaks of 471.6/933.5 arcsec, root-mean-square roughness of 0.52 nm and electron mobility of 2 000 cm2/(V·s). Finally, large-size wafe-scale GaN microwave material was successfully separated from sapphire substrate by a mechanical lift-off process, providing convenience for transfering to high thermal conductivity substrates and creating conditions for fabricating high-power RF devices.

Key words: vdW heteroepitaxy, MOCVD, GaN microwave material, few-layer BN, stress modulation

CLC Number: