A new method to enhance mobility of poly-Si TFT recrystallized by excimer laser annealing

A SEM study after dry etching was conducted for poly-Si films recrystallized by excimer laser annealing. It was found that the grain size could be enlarged to about 300 nm using the low-temperature (400 degrees C) substrate heating method. The authors propose a low-temperature (<600 degrees C) substrate heating method during excimer laser annealing with a structure composed of a-Si(1000 AA)/SiO/sub 2//glass, which has been adopted to reduce thermal damage. By numerical simulation and experimental investigation, the authors demonstrated that it is possible to realize enlargement of the grain size and enhancement to a high field effect mobility of 147 cm/sup 2//V-s without thermal damage to the glass substrate using the method.