Poly-Si TFT fabricated by ion beam sputtering and excimer laser annealing at 100 degrees C

摘要

Polycrystalline silicon (poly-Si) thin film transistors (TFT's) have been fabricated by ion beam sputtering (IBS) and XeCl excimer laser annealing (ELA) at 100degreesC. The amorphous silicon (a-Si) films to be crystallized into poly-Si were deposited by IBS and they had very low argon content (less than 1 at. %). No explosive gas evolution was observed during the instantaneous crystallization of the a-Si film by ELA, while the a-Si film deposited by conventional RF/DC magnetron sputtering or PECVD underwent severe silicon film ablation due to the explosive argon or hydrogen evolution during ELA. The poly-Si TFT fabricated by IBS and ELA exhibited an ON/OFF current ratio of 4 x 10(4). The measured sheet resistance of the n(+)-doped source/drain resistance was less than 700 Omega/sq. and the output I-D-V-DS curves showed that good ohmic contacts were formed. [References: 5]