Device degradation in n- and p-channel polysilicon TFTs as a function of different electrical stress configurations

Electrical stress testing of polysilicon TFTs is a very valuable tool for addressing concerns about device reliability and stability. We have examined two distinct bias stresses on ECR and RF hydrogenated polysilicon TFTs and have compared the degradation mechanisms in n- and p-channel devices. We present evidence that hydrogen motion can play a role in TFT response to these stresses and show that the response can be very different for n- and p-channel TFTs.