Low-temperature materials and thin film transistors for flexible electronics

摘要

The paper reviews the material requirements of nanocrystalline silicon (nc-Si) in terms of thin film transistors (TFTs) and configuration for display application. We studied the material qualities of nc-Si films deposited by 13.56 MHz plasma-enhanced chemical vapor deposition (PECVD) from a conventional H2 dilution in SiH4 at low temperature. Some types of intrinsic nc-Si films deposited at the high pressure and the low pressure were studied. A further improvement in the nc-Si:H film structure and properties is obtained by adjusting the r.f. power and the deposition temperature. The material properties were characterized with Raman spectroscopy measurements to reveal 76% of crystalline volume fraction. The nc-Si crystalline were mainly determined by the ratio of H and SiH3[l-3]. The nc-Si with optimized deposition condition was used as the channel layers of TFTs to investigate the effect of nc-Si qualities for the TFTs application.