Author(s): Zhao, S (Zhao, Shuai); Yuan, GD (Yuan, Guodong); Zhu, QH (Zhu, Qiuhao); Song, LH (Song, Luhang); Zhang, D (Zhang, Di); Liu, YM (Liu, Yumeng); Lu, J (Lu, Jun); Han, WH (Han, Weihua); Luo, JW (Luo, Junwei)

Source: IEEE TRANSACTIONS ON ELECTRON DEVICES DOI: 10.1109/TED.2022.3158628 Early Access Date: MAR 2022

Abstract: Cryogenic mobility enhancement, corresponding to the reduction of interfacial disorder, is always a research focus in Si-based MOS device manufacturing toward practical quantum computing chips. In this work, we report the dependency of MOSFET cryogenic mobility on reactive ion etching (RIE)-induced damages at 5-75 K. We discover that RIE will introduce a lot of atomic steps and charged traps at SiO2/Si interfaces or conducting channel boundaries during the mesa formation stage, severely degrading device mobility, especially at a low temperature. With a post-RIE high-temperature SiO2 regrowth process, the device cryogenic (1.8 K) peak mobility is enhanced to similar to 20314 cm(2)/(V-s) at a small electron density of 1.05 x 10(12)/cm(2), meaning the successful removal of RIE-induced extra effective scattering centers within the optimized device. Notably, our work presents the adverse impacts of RIE on MOS device cryogenic mobilities and provides a feasible integration flow to recover device performances, which may promote the evolution of Si-based MOS quantum dot computation.

Accession Number: WOS:000777269200001

ISSN: 0018-9383

eISSN: 1557-9646

Full Text: https://ieeexplore.ieee.org/document/9741705