Real time evaluation of silicon epitaxial growth process by exhaust gas measurement using quartz crystal microbalance

Abstract

A silicon epitaxial growth process in a trichlorosilane-hydrogen system was evaluated using a quartz crystal microbalance (QCM) placed at the exhaust of a chemical vapor deposition reactor designed for the Minimal Fab. The QCM showed two types of the frequency decrease behaviors, that is, i) a quick shift due to the gas property change caused by the trichlorosilane gas introduction into the ambient hydrogen and ii) the continuous and gradual decrease due to the byproduct deposition on the QCM surface during the silicon epitaxial growth. Because both i) and ii) showed a relationship with the silicon epitaxial growth rate, the in-situ information obtained by the QCM was expected for the real time monitoring of the film deposition process.

Advantages of a slim vertical gas channel at high SiHCl3 concentrations for atmospheric pressure silicon epitaxial growth

“…These advantages were experimentally recognized and verified by the specular silicon epitaxial film surface, no parasitic deposition and the real-time process information, as reported elsewhere [24].…”

Deposition and etching behaviour of boron trichloride gas at silicon surface

“…In the report applying the QCM to exhaust gas evaluation for the Minimal CVD system [22], the gas property change and the byproduct deposition at the exhaust of reactor were shown to be related to the silicon film deposition occurred in the reactor. The detection limit of QCM used in this study was 0.5 ng cm -2 , which was significantly lower than the silicon monolayer of 60 ng cm -2 .…”

Quartz crystal microbalance for real-time monitoring chlorosilane gas transport in slim vertical cold wall chemical vapor deposition reactor

“…The dichlorosilane gas behaviour was observed in this study. The measurement and calculation of the trichlorosilane gas transport behaviour obtained in previous studies [18,19] were further evaluated and compared with that of dichlorosilane gas.…”

“…For this purpose, a piezoelectric crystal microbalance [14][15][16][17][18], such as a quartz crystal microbalance (QCM), was considered. The QCM is a simple, small and low-cost sensor.…”

“…It could sensitively detect various phenomena that occurred related to the CVD process, such as the gas density and viscosity change in the reactor in addition to the deposition on the surface [14][15][16][17]. In the first study applying the QCM to the Minimal CVD system [18], the gas property change and the byproduct deposition at the exhaust of the reactor were studied relating to the silicon film deposition in a trichlorosilane-hydrogen system.…”