| 摘要 |
PURPOSE: To decrease the number of times of processes, and to increase the yield rare and to improve the characteristic of a thin-film transistor by forming a first-conductivity type second impurity region of LDD construction, in a semiconductor layer on an insulating substrate other than a gate electrode part. CONSTITUTION: A gate electrode 2 is formed on an insulating substrate 1, and a gate insulating film 3 such as an oxide film, etc., is formed on the gate electrode 2 and the substrate 1, and a semiconductor layer 4 is formed on the gate insulating film 3. Besides, the channel region 11 of a transistor is formed in a part along both side surfaces of the gate electrode 2 of the semiconductor layer 4, and a high-concentration p-type first impurity region 9 is formed in the upper of the gate electrode 2. Furthermore, p-type second impurity regions 10a, 10b of LDD construction are formed in the semiconductor layer 4 on the substrate 1 excluding the part of the gate electrode 2. Consequently, it becomes possible to form a drain region of LDD construction by self aligning without a masking process, so it becomes possible to obtain a constant characteristic irrespective of a process change, and to increase the yield rate. |
