Optimization of extrinsic TFT mobility on 550 mm × 650 mm large glass

For large area liquid-crystal-displays (LCDs), hydrogenated amorphous silicon (a-Si) thin film transistors (TFTs) with large current drive are required. We have maximized the extrinsic TFT mobility on 550 mm × 650 mm large area glass substrates by optimization of n+ a-Si plasma enhanced-chemical vapor deposition (PE-CVD) conditions to minimize the TFT contact resistance. The contact resistance is measured using test element group (TEG) TFTs with different channel lengths. The resistance of contacts between source/drain electrode and a-Si layer affects the extrinsic mobility. © 1998 Elsevier Science Ltd. All rights reserved.