THIN FILM SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a thin film semiconductor device suitable to drive with a small power consumption and to display a high quality image, by integrating a thin film transistor for a circuit drivable at a low voltage and a thin film transistor for a pixel having a small leakage current on the same substrate. SOLUTION: A pixel array of the thin film semiconductor device has pixel electrodes 11 and thin film transistors TFT-PXL for the pixels to switch to drive the electrodes 11. A peripheral circuit has a drive circuit including the thin film transistors TFT-CKT for the circuit for driving the thin film transistors for the pixels. Each thin film transistor has a laminated structure obtained by overlapping a semiconductor thin film 5, a gate electrode 1 and gate insulating films 2 and 3 interposed between the film 5 and the electrode 1. The film 5 has a channel region ch disposed at an inside from an end E of the electrode 1, a low concentration impurity region LDD continuing to the outside of the channel region, a high concentration impurity region S/D continuing to the outside of the low concentration impurity region, and a concentration boundary B isolated via the low concentration impurity region and the high concentration impurity region. A position X of the boundary B measured with the end E of the gate electrode as a reference is set at the TFT-CKT side to the inside from the TFT- PXL.