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:
Apr. 14, 2015
Filed:
Oct. 04, 2013
Abb Technology Ag, Zürich, CH;
Munaf Rahimo, Uezwil, CH;
Arnost Kopta, Zürich, CH;
Thomas Clausen, Seengen, CH;
Maxi Andenna, Dättwil, CH;
ABB Technology AG, Zurich, CH;
Abstract
A method for manufacturing a bipolar punch-through semiconductor device is disclosed, which includes providing a wafer having a first and a second side, wherein on the first side a high-doped layer of the first conductivity type having constant high doping concentration is arranged; epitaxially growing a low-doped layer of the first conductivity type on the first side; performing a diffusion step by which a diffused inter-space region is created at the inter-space of the layers; creating at least one layer of the second conductivity type on the first side; and reducing the wafer thickness within the high-doped layer on the second side so that a buffer layer is created, which can include the inter-space region and the remaining part of the high-doped layer, wherein the doping profile of the buffer layer decreases steadily from the doping concentration of the high-doped region to the doping concentration of the drift layer.