Method for manufacturing thin film transistor and thin film transistor

Application Number: 00108644
Application Date: 2000.05.09
Publication Number: 1273436
Publication Date: 2000.11.15
Priority Information: 1999/5/10 JP 128121/99
International: H01L21/336;H01L29/786
Applicant(s) Name: Matsushita Electric Industrial Co., Ltd.
Inventor(s) Name: Kota Mamoru;Aiba Isaoko
Patent Agency Code: 31100
Patent Agent: zhang zhengquan
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 lambd 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 lambd 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.