Control and analysis of leakage currents in poly-Si thin-film transistors

Control of leakage current in autoregistered columnar and a solid phase crystallized poly-Si thin-film transistors (TFTs) is discussed. For n-channel TFTs, two parasitic leakage current paths, due to bulk conduction and back interface conduction, have been identified. It is demonstrated that these can be controlled by using sufficiently thin films and by low dose boron back channel implants, respectively. By these means, generation limited leakage currents, with values of