Electrical properties of MBE-Y2O3/In0.1Ga0.9As MOS capacitors and GaAs-based inversion-channel MOSFETs

• Main Authors: Jun-Hao Huang, 黃俊豪
• Other Authors: Minghwei Hong
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/467hmc

碩士 === 國立臺灣大學 === 電子工程學研究所 === 106 === Si-based metal oxide semiconductor field-effect -transistors (MOSFETs) have undergone extreme scaling in the past few decades fulfilling Moore''s law. As the production for 7 nm node complementary MOS (CMOS) is around the corner, diverse solutions have been proposed for future high speed CMOS devices. Among them, introducing high carrier mobility III-V compound semiconductors as channel material is a very promising approach. It provides an effective way to enhance the device performance having less power consumption without the need for further aggressive scaling. In this thesis, low interfacial trap density (Dit) and high temperature thermal stability have been achieved with in-situ molecular-beam-epitaxy (MBE) Y2O3 on In0.1Ga0.9As (001). In this work, the hetero-structure has endured 1000 oC post deposition annealing while maintaining a leakage current density at 10-8 A/cm-2 and well-behaved capacitance-voltage (C-V) characteristics. Ultra-low frequency dispersions of 3% and 11.8% in C-V at accumulation region were obtained on p-type and n-type In0.1Ga0.9As(001), respectively. Low Dit values of (3.5-20)×1011 eV-1cm-2 were extracted by quasi-static CV (QSCV) in the whole bandgap of InGaAs. Therefore, in-situ MBE-Y2O3 has effectively passivated In0.1Ga0.9As (001) with excellent thermal stability at very high temperatures and a low Dit, critical for enabling the fabrication of high performance InGaAs MOSFETs. The device performance of a 1 µm gate length self-aligned inversion-channel In0.1Ga0.9As MOSFET on GaAs (001) substrate using a gate dielectric of Al2O3 (5 nm thick)/Y2O3 (1.5 nm thick) with a maximum drain current of 9.6 μA/μm. For improve the device performance, we deposition SiO2 to protect gate region before ion-implantation process, the drain leakage current in off-state and Ion/Ioff ratio are improve from 10-4 μA/μm to 10-7 μA/μm and 2.7 to 4.5 respectively.