A Dehydrogenation and Annealing Method of a-Si by Microwave

We propose a new method for selective crystallization of amorphous silicon and source/drain ion impurities activation by microwave annealing. We have measured FTIR to investigate hydrogen content variation in PECVD a-Si film and examined the poly-Si grain structure by SEM. We have also observed the Raman spectroscopy in order to investigate the grain growth mechanism during microwave annealing. In our experiment, a-Si layer between microwave absorbing layers was fully crystallized in 60 seconds and hydrogen content of a-Si under microwave reflective layer was not varied after 20 minutes microwave annealing. These results indicate that proposed method may be implemented for fabricating a-Si and poly-Si TFTs on the same glass substrate. We have fabricated the poly-Si and a-Si TFTs employing microwave annealing for active layer crystallization and source/drain activation by our method.