Polycrystalline silicon thin-film transistors with location-controlled crystal grains fabricated by excimer laser crystallization

Abstract

In this paper, location-controlled silicon crystal grains are fabricated by the excimer laser crystallization method which employs amorphous silicon spacer structure and prepatterned thin films. The amorphous silicon spacer in nanometer-sized width formed using spacer technology is served as seed crystal to artificially control superlateral growth phenomenon during excimer laser irradiation. An array of 1.8-mu m-sized disklike silicon grains is formed, and the n-channel thin-film transistors whose channels located inside the artificially-controlled crystal grains exhibit higher performance of field-effect-mobility reaching 308 cm(2)/V s as compared with the conventional ones. This position-manipulated silicon grains are essential to high-performance and good uniformity devices. (c) 2007 American Institute of Physics.