The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 18, 1997
Filed:
Feb. 09, 1995
Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken, JP;
Abstract
In forming a thin film transistor (TFT) having an offset structure or a lightly doped drain (LDD) structure, a blocking material having a lower etching rate than that of a material constructing a gate electrode is formed. By using the blocking material as a mask, a gate electrode material is side-etched selectively to form gate electrodes. The blocking material is processed selectively and remains in a drain region side. Also, an offset region or an LDD region is formed under the blocking material by performing an impurity ion implantation. On the other hand, after the gate electrodes are formed, a resist is added and then light exposure is performed from a source region side using a light blocking material as a mask, so that the resist remains in a drain region side of the gate electrode. Also, by implanting an impurity ion, an offset region or an LDD region is formed in the drain region side.