2D Simulation Study of p-Type TFTs with Chemically Deposited Poly-PbS Active Channel

© MIDEM Society. In this work, the two-dimensional (2D) numerical simulation of p-Type poly-PbS TFT electrical characteristics are performed using a physically based device simulator Atlas/Silvaco. The analytical expressions of defect density models for acceptor-and donor-like traps are defined for poly-PbS thin film material deposited with chemical bath deposition technique. The parameters of defect density model are optimized based on Levenberg-Marquardt algorithm to fit simulated and experimental results of TFTs. It is shown that the spatially uniform density of defect states method used for trapped charge evaluation in Atlas gives good agreement between simulated and experimental characteristics. An important presence of deep (Gaussian) acceptor-and donor-like density of states in poly-PbS band gap is confirmed. By controlling cation (donor-like) and anion (acceptor-like) vacancies of poly-PbS films could improved the performance of p-Type TFTs.