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:
Sep. 13, 2011
Filed:
Jul. 17, 2008
Yoshiaki Hisamoto, Chiyoda-ku, JP;
Yoshiaki Hisamoto, Chiyoda-ku, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
Abstract
A semiconductor device having the present high withstand voltage power device IGBT has at a back surface a p collector layer with boron injected in an amount of approximately 3×10/cmwith an energy of approximately 50 KeV to a depth of approximately 0.5 μm, and an nbuffer layer with phosphorus injected in an amount of approximately 3×10/cmwith an energy of 120 KeV to a depth of approximately 20 μm. To control lifetime, a semiconductor substrate is exposed to protons at the back surface. Optimally, it is exposed to protons at a dose of approximately 1×10/cmto a depth of approximately 32 μm as measured from the back surface. Thus snapback phenomenon can be eliminated and an improved low saturation voltage (Vce (sat))-offset voltage (Eoff) tradeoff can be achieved.