Suppression of Schottky leakage current in island-in amorphous silicon thin film transistors with the Cu/CuMg as source/drain metal

Abstract

The feasibility of using Cu/CuMg as a source/drain metal for the island-in amorphous silicon thin film transistors (a-Si:H TFTs) has been investigated. The issue of adhesion between the Cu film and n(+)-a-Si layer has been overcome by introducing the Cu/CuMg alloy. Furthermore, the suppression of Schottky leakage current in metal/a-Si:H structure was also observed in the island-in a-Si:H TFT. The island-in a-Si:H TFT exhibited the mobility of 0.52 cm(2)/V s, the subthreshold slope of 0.78 V/decade, and the V-th of 3.02 V. The experimental result also showed superior performance of the a-Si:H TFT with minimal loss of critical dimension and good thermal stability.