Title
Simple way of finding Ba to Si deposition rate ratios for high photoresponsivity in BaSi2 films by Raman spectroscopy
Author
Yudai Yamashita, Yuuki Takahara, Takuma Sato, Kaoru Toko, Akira Uedono and Takashi Suemasu
Year
2019
Journal
Applied Physics Express
Abstract
Since the photoresponsivity of BaSi2 is sensitive to a Ba-to-Si deposition rate ratio (R Ba/R Si), there is a need to determine the optimum value of R Ba/R Si. We grew 0.5 μm thick BaSi2 films with R Ba/R Sivaried from 1.1–3.6 at 580 °C and 0.4–4.7 at 650 °C. The photoresponsivity reached a maximum at RBa/R Si = 2.2 and 1.2, respectively. Raman spectroscopy revealed that the crystalline quality of BaSi2became better with decreasing R Ba/R Si. However, as R Ba/R Si decreased further beyond these values, excess Si precipitated, showing that the optimum value of R Ba/R Si should be as small as possible without causing Si precipitates to form.
Instrument
NRS-5100
Keywords
Raman Imaging Spectroscopy, Barium, photoresponsivity