US 6,982,473 B2
Bipolar transistor
Akio Iwabuchi, Saitama (Japan); and Shigeru Matsumoto, Saitama (Japan)
Assigned to Sanken Electric Co., Ltd., Saitama (Japan)
Filed on Aug. 09, 2004, as Appl. No. 10/914,329.
Claims priority of application No. 2003-296848 (JP), filed on Aug. 20, 2003.
Prior Publication US 2005/0040431 A1, Feb. 24, 2005
Int. Cl. H01L 27/082 (2006.01); H01L 27/102 (2006.01); H01L 29/70 (2006.01); H01L 31/11 (2006.01)
U.S. Cl. 257—565 9 Claims
OG exemplary drawing
 
1. A semiconductor element comprising:
a first semiconductor region of a first conductivity type;
a second semiconductor region of a second conductivity type that contacts a side surface of the first semiconductor region, and is formed so as to surround the first semiconductor region;
a third semiconductor region of the second conductivity type that is formed at a surface region of said first semiconductor region;
a fourth semiconductor region of the first conductivity type that is formed at the surface region of the first semiconductor region, respectively separated a predetermined distance from the third semiconductor region, and has a higher impurity concentration than the impurity concentration of the first semiconductor region;
a fifth semiconductor region of the second conductivity type that is formed at the surface region of the first semiconductor region, and is placed in between the third semiconductor region and the fourth semiconductor region, separated a predetermined distance from the third semiconductor region and the fourth semiconductor region;
a sixth semiconductor region of the first conductivity type, having a higher impurity concentration than the impurity concentration of the first semiconductor region, that is formed at the surface region of the first semiconductor region, includes a region in between the fourth semiconductor region and the fifth semiconductor region, and is placed so as to contact the fifth semiconductor region;
a first electrode that is electrically connected to the third semiconductor region;
a second electrode that is electrically connected to the fourth semiconductor region, and
a third electrode that is electrically connected to the fifth semiconductor region.