US 9,812,537 B2
Semiconductor device and method for manufacturing the same
Yuki Nakano, Kyoto (JP)
Assigned to ROHM CO., LTD., Kyoto (JP)
Appl. No. 14/768,116
Filed by ROHM CO., LTD., Kyoto-shi, Kyoto (JP)
PCT Filed Feb. 14, 2014, PCT No. PCT/JP2014/053511
§ 371(c)(1), (2) Date Aug. 14, 2015,
PCT Pub. No. WO2014/129404, PCT Pub. Date Aug. 28, 2014.
Claims priority of application No. 2013-030018 (JP), filed on Feb. 19, 2013.
Prior Publication US 2015/0380503 A1, Dec. 31, 2015
Int. Cl. H01L 29/78 (2006.01); H01L 29/423 (2006.01); H01L 29/40 (2006.01); H01L 29/66 (2006.01); H01L 29/06 (2006.01); H01L 29/16 (2006.01); H01L 29/20 (2006.01); H01L 29/10 (2006.01)
CPC H01L 29/4236 (2013.01) [H01L 29/0623 (2013.01); H01L 29/1602 (2013.01); H01L 29/1608 (2013.01); H01L 29/2003 (2013.01); H01L 29/407 (2013.01); H01L 29/66045 (2013.01); H01L 29/66068 (2013.01); H01L 29/66613 (2013.01); H01L 29/66734 (2013.01); H01L 29/78 (2013.01); H01L 29/7811 (2013.01); H01L 29/7813 (2013.01); H01L 29/0653 (2013.01); H01L 29/0696 (2013.01); H01L 29/1095 (2013.01)] 27 Claims
OG exemplary drawing
 
1. A semiconductor device comprising:
a semiconductor layer of a first conductivity type formed with a gate trench;
a gate electrode buried in the gate trench via a gate insulating film;
a source region of a first conductivity type disposed in a manner exposed on a surface of the semiconductor layer, forming a part of a side face of the gate trench;
a channel region of a second conductivity type disposed for the source region on a back surface side of the semiconductor layer in a manner contacting the source region, forming a part of the side face of the gate trench;
a drain region of a first conductivity type disposed for the channel region on the back surface side of the semiconductor layer in a manner contacting the channel region, forming a bottom face of the gate trench;
a second trench selectively formed in a source portion defined in a manner containing the source region in the surface of the semiconductor layer;
a trench buried portion buried in the second trench;
a channel contact region of a second conductivity type selectively disposed at a position higher than that of a bottom portion of the second trench in the source portion, electrically connected with the channel region;
a surface metal layer disposed on the source portion, electrically connected to the source region and the channel contact region; and
a second conductivity-type layer formed at the bottom portion and a side portion of the second trench in a manner continuing from the channel region and the channel contact region.