Patent Number: 6,309,917

Title: Thin film transistor manufacturing method and thin film transistor

Abstract: A first insulation film is formed as a gate insulation film of a thin film transistor, and a gate electrode is formed on the gate insulation film. Then, dopant is implanted to form source and drain regions. A second insulation film having refractive index n1 and film thickness d2 is formed to cover the first insulation film and gate electrode as an interlayer insulation film. After forming the second insulation film, laser with wavelength .lambda. is applied to activate the dopant. The film thicknesses d1 and d2 of the first and second insulation films satisfy conditions against the laser wavelength .lambda. for forming a reflection protective film at regions where activation is necessary. At the same time, the film thicknesses d1 and d2 are set in a way that the interlayer insulation film on the gate electrode forms a reflective film. This reduces the thermal damage to the gate electrode from the laser during dopant activation.

Inventors: Furuta; Mamoru (Ishikawa, JP), Soma; Koji (Ishikawa, JP)

Assignee: Matsushita Electric Industrial Co., Ltd.

International Classification: H01L 21/02 (20060101); H01L 29/66 (20060101); H01L 21/336 (20060101); H01L 29/786 (20060101); H01L 021/76 ()

Expiration Date: 10/30/2018