Display device and manufacturing method thereof

US7968885B2 · kind B2 · utility

Assignee

• Semiconductor Energy Laboratory Co., Ltd. · JP

Inventors

• Satoshi Kobayashi · Saitama, JP
• Yoshiyuki Kurokawa · Yokohama, JP
• Shunpei Yamazaki · Setagaya, JP
• Daisuke Kawae · Hiratsuka, JP

Key dates

• Filing date: Aug 6, 2008
• Grant date: Jun 28, 2011
• Expiry date: Apr 7, 2029

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/40

Abstract

To provide a display device having a thin film transistor with high electric characteristics and excellent reliability and a manufacturing method thereof. A gate electrode, a gate insulating film provided over the gate electrode, a first semiconductor layer provided over the gate insulating film and having a microcrystalline semiconductor, a second semiconductor layer provided over the first semiconductor layer and having an amorphous semiconductor, and a source region and a drain region provided over the second semiconductor layer are provided. The first semiconductor layer has high crystallinity than the second semiconductor layer. The second semiconductor layer includes an impurity region having a conductivity type different from a conductivity type of the source region and the drain region between the source region and the drain region.