| CPC H10D 12/481 (2025.01) [H01L 21/76897 (2013.01); H10D 12/038 (2025.01); H10D 62/106 (2025.01); H10D 62/127 (2025.01); H10D 62/133 (2025.01); H10D 62/137 (2025.01); H10D 62/177 (2025.01); H10D 62/393 (2025.01); H10D 64/01 (2025.01); H10D 64/513 (2025.01); H10D 64/516 (2025.01); H10D 64/518 (2025.01); H10D 64/62 (2025.01); H10D 8/422 (2025.01); H10D 84/811 (2025.01)] | 25 Claims |
|
1. A semiconductor device comprising:
a plurality of trenches with each trench of the plurality of trenches having a stripe-shape and a pair of linear sidewalls continuously provided from a surface of a semiconductor substrate to a curved interface in form of a curved bottom surface between the pair of linear sidewalls of each trench of the plurality of trenches in a depth direction, each trench of the plurality of trenches extending in parallel to each other in which a polysilicon electrode is provided through an insulating film;
a plurality of mesa regions between adjacent trenches of the plurality of trenches, the plurality of mesa regions constituted by a minute-pattern in a range with a width of 0.1 micro meters to 1.0 micro meter;
an interlayer insulating film covers a top surface of the plurality of mesa regions;
a plurality of contact holes in the interlayer insulating film between the adjacent trenches,
each contact hole of the plurality of contact holes corresponds to a mesa region of the plurality of mesa regions above the top surface of the mesa region between the adjacent trenches,
each contact hole of the plurality of contact holes penetrates the interlayer insulating film to the top surface of each mesa region of the plurality of mesa regions, and
each contact hole of the plurality of contact holes extends along the plurality of trenches in a longitudinal direction in a plan view;
a metal material buried in the plurality of contact holes;
a plurality of emitter regions of a first conductivity type periodically provided in the plurality of mesa regions along the longitudinal direction so as not to overlap the polysilicon electrode in the plan view;
a base region of a second conductivity type provided immediately below the plurality of emitter regions; and
a plurality of contact regions of the second conductivity type having a higher impurity concentration than the base region, provided in the longitudinal direction so as not overlap the polysilicon electrode in the plan view,
wherein
a length of a surface of an emitter region, among the plurality of emitter regions, in the longitudinal direction in the plan view is greater than a length of a surface of a contact region, among the plurality of contact regions, between two emitter regions among the plurality of emitter regions,
a length of an interface of a contact region, among the plurality of contact regions, with the base region in the longitudinal direction is greater than a length of an interface of the emitter region with the base region in the longitudinal direction, and
the metal material buried in a contact hole among the plurality of contact holes includes:
a barrier-metal film covering at least a part of an inner wall of the contact hole; and
tungsten plug including a tungsten film in contact with the barrier-metal film and provided in the contact hole, so that the tungsten plug is in contact with the mesa region constituted by the minute-pattern via the barrier-metal film, resulting in a contact area of the tungsten plug with the emitter region being larger than that with the contact region.
|