Fabrication of High-Quality and Strain-Relaxed GeSn Microdisks by Integrating Selective Epitaxial Growth and Selective Wet Etching Methods

Nanoscale Research Letters

Xinju Yang¹  Tao Liu¹  Zhenyang Zhong¹  Zuimin Jiang¹  Guangjian Zhu¹  Liming Wang² 

[1] State Key Laboratory of Surface Physics, Department of Physics, Fudan University;Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory, School of Microelectronics, Xidian University;

关键词: GeSn microdisk;    Molecular beam epitaxy;    Selective wet etching;    Micro-Raman spectroscopy;    Strain relaxation;   

DOI  :  10.1186/s11671-020-3251-0

来源: DOAJ

【 摘 要 】

Abstract GeSn is a promising material for the fabrication of on-chip photonic and nanoelectronic devices. Processing techniques dedicated to GeSn have thus been developed, including epitaxy, annealing, ion implantation, and etching. In this work, suspended, strain-relaxed, and high-quality GeSn microdisks are realized by a new approach without any etching to GeSn alloy. The GeSn alloy was grown on pre-patterned Ge (001) substrate by molecular beam epitaxy at low temperatures. The transmission electron microscopy and scanning electron microscopy were carried out to determine the microstructures of the GeSn samples. The microdisks with different diameters of Ge pedestals were fabricated by controlling the selective wet etching time, and micro-Raman results show that the microdisks with different dimensions of the remaining Ge pedestals have different extents of strain relaxation. The compressive strain of microdisks is almost completely relaxed under suitable conditions. The semiconductor processing technology presented in this work can be an alternative method to fabricate innovative GeSn and other materials based micro/nano-structures for a range of Si-compatible photonics, 3D-MOSFETs, and microelectromechanical device applications.

【 授权许可】

Unknown