High performance micro-crystalline silicon TFT using indirect thermal crystallization technique

摘要

For Active matrix liquid crystal display (AMLCD) and active matrix organic light emitting diode (AMOLED) applications, Hydrogenated amorphous silicon (a-Si:H) and low temperature poly silicon (LTPS) have been widely used. However, the performance of a-Si:H such as field effect mobility and electrical stability are needed to be improved with the increasing demands of high definition and large sized display. And LTPS is having issues of non-uniform TFT characteristics on large size substrate and high production cost due to the excimer laser annealing method. With these backgrounds, various method of crystallization has been investigated such as metal induced crystallization (MIC), sequential lateral solidification (SLS), solid phase crystallization (SPC) and Xe flash lamp annealing (FLA) etc. (3-6). But technical issues mentioned above are still being challenged. We investigated indirect thermal crystallization technique employing diode laser beam for the fabrication of 5 mask processed uc-Si TFT, which is able to be adopted to the conventional a-Si TFT process.