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:
Jul. 14, 1998
Filed:
Sep. 30, 1996
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor device is provided for convenient checking of etching states of semiconductor layers, along with a process for its preparation, wherein a test layer is formed on the same wafer where a semiconductor product is manufactured, and concurrently with and under the same formation conditions as formation a target layer forming a part of the semiconductor product, wherein the test layer is formed on a first layer and on a second layer interposed between a portion of the test layer and the first layer, with one of the first and second layers having the same etching properties as the target layer and the other of the first and second layers having different etching characteristics from the target layer. After etching the test layer and target layer concurrently to form holes in each the amount of the etching of the holes can be measured by an electron microscope, and the amount of etching in the target layer of the semiconductor product is controlled from the state of the etching reaching to the lower layer, either the first or second layer, below the test layer.