In-situ determination of silane gas utilization and deposition rate for different deposition regimes of μc-Si:H using FTIR and OES in-situ

For the deposition of microcrystalline silicon it is important to increase the deposition rate and silane utilization rate. In the past, a method based on optical emission spectroscopy (OES) has been introduced to obtain the transition point from amorphous to crystalline growth in-situ, which is the point for optimum microcrystalline silicon solar cell conditions. The method is based on alternating deposition by a silane/hydrogen plasma and etching by a pure hydrogen plasma. This paper combines OES with Fourier transform infrared (FTIR) spectroscopy in the exhaust line to determine the growth rate in-situ. In this way, the multidimensional space of silane flow, deposition rate and gas utilization rate is determined in-situ in one deposition. It is aimed to increase the gas utilization rate towards 100%.