Nanocrystalline-Si thin film deposited by inductively coupled plasma chemical vapor deposition (ICP-CVD) at 150°C

Nanocrystalline silicon (nc-Si) films were deposited by inductively coupled plasma chemical vapor deposition (ICP-CVD) at 150 degrees C. ICP power was 400W. The process gas was SiH4 diluted with He as well as H-2. The flow rate of He, H-2 and He/H-2 mixture was varied from 20sccm to 60scem and that of SiH4 was 3sccm. X-ray diffraction (XRD) patterns of the nc-Si films were measured. From the XRD results of nc-Si films deposited by ICP-CVD, the properties of Si film deposited under each condition were studied. As the dilution ratio increases and He/H-2, mixture was used as a dilution gas, intensities of < 111 > and < 220 > peaks were increased and the incubation layer was thin. These results were explained in the point of role of H-2 plasma and He plasma in the nc-Si deposition process. Our experimental results show that nc-Si film deposited by ICP-CVD may be Suitable for an active layer of nc-Si TFTs.