Absorption Amelioration of Amorphous Si Film by Introducing Metal Silicide Nanoparticles

• Published in: Nanoscale research letters Vol. 12; no. 1; p. 224
• Main Authors: Sun, Hui, Wu, Hsuan-Chung, Chen, Sheng-Chi, Ma Lee, Che-Wei, Wang, Xin
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2017; Springer Nature B.V; SpringerOpen
• Subjects: Absorption; Absorption ability; Aluminum; Amorphous silicon; Annealing; Chemistry and Materials Science; Diffusion; Intermetallic compounds; Materials Science; Metal silicide; Metal silicides; Metals; Molecular Medicine; Nano Express; Nanochemistry; Nanoparticles; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Nickel silicide; Radio frequency; RF sputtering; Silicon films; Temperature effects; Thin films; Vacuum; Amorphous silicon; RF sputtering; Absorption ability; Metal silicide
• ISSN: 1931-7573; 1556-276X
• DOI: 10.1186/s11671-017-2003-2

Amorphous Si (a-Si) films with metal silicide are expected to enhance the absorption ability of pure a-Si films. In this present study, NiSi (20 nm)/Si (40 nm) and AlSi (20 nm)/Si (40 nm) bilayer thin films are deposited through radio frequency (RF) sputtering at room temperature. The influence of the film’s composition and the annealing temperature on the film’s optical absorption is investigated. The results show that all the NiSi/Si films and AlSi/Si films possess higher absorption ability compared to a pure a-Si film (60 nm). After annealing from 400 to 600 °C under vacuum for 1 h, the Si layer remains amorphous in both NiSi/Si films and AlSi/Si films, while the NiSi layer crystallizes into NiSi 2 phase, whereas Al atoms diffuse through the whole film during the annealing process. Consequently, with increasing the annealing temperature, the optical absorption of NiSi/Si films increases, while that of AlSi/Si films obviously degrades.