Methodology for fabricating a thin film transistor, including an LDD region, from amorphous semiconductor film deposited at 530amp;deg; C. or less using low pressure chemical vapor deposition

摘要

A high-performance thin-film semiconductor device and a simple fabrication method is provided. After a silicon film is deposited at approximately 530° C. or less and at a deposition rate of at least approximately 6 Å/minute, thermal oxidation is performed. This ensures an easy-and simple fabrication of a high-performance thin-film semiconductor device. A thin-film semiconductor device capable of low-voltage and high-speed drive is provided. The short-channel type of a TFT circuit with an LDD structure reduces a threshold voltage, increases speed, restrains the power consumption and increases a breakdown voltage. The operational speed of the thin-film semiconductor device is further increased by optimizing the maximum impurity concentration of an LDD portion, a source portion a drain portion, as well as optimizing the LDD length and the channel length. A display system is provided using these TFTs having drive signals at or below approximately the TTL level.