Thermal stability of germanium-tin (GeSn) fins

• Main Authors: Lei, Dian, Lee, Kwang Hong, Bao, Shuyu, Wang, Wei, Masudy-Panah, Saeid, Tan, Chuan Seng, Tok, Eng Soon, Gong, Xiao, Yeo, Yee-Chia
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2018
• Subjects: Crystallography; Surface And Interface Chemistry; DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/102622; http://hdl.handle.net/10220/47272
• Institution: Nanyang Technological University

We investigate the thermal stability of germanium-tin (Ge1−xSnx) fins under rapid thermal annealing in N2 ambient. The Ge1−xSnx fins were formed on a GeSn-on-insulator substrate and were found to be less thermally stable than blanket Ge1−xSnx films. The morphology change and material quality of the annealed Ge1−xSnx fin are investigated using scanning electron microscopy, Raman spectroscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, and electron energy loss spectroscopy. Obvious degradation of crystalline quality of the Ge0.96Sn0.04 fin was observed, and a thin Ge layer was formed on the SiO2 surface near the Ge0.96Sn0.04 fin region after 500 °C anneal. A model was proposed to explain the morphology change of the Ge0.96Sn0.04 fin.