Semiconductor device having a structure in which a field plate electrode and a gate electrode are buried in different trenches
A semiconductor device according to the present embodiment includes: a first electrode; a first semiconductor region of a first conductivity type disposed above the first electrode; a second semiconductor region of a second conductivity type disposed on the first semiconductor region; a third semiconductor region of the first conductivity type disposed on the second semiconductor region; a second electrode disposed in the first semiconductor region; a third electrode facing the second semiconductor region via a second insulating film; a fourth electrode having a portion adjacent to a part of the second semiconductor region and the third semiconductor region in the second direction, the second semiconductor region, and the third semiconductor region; and a fifth electrode disposed in the first insulating film, having a bottom located closer to the first electrode than a bottom of the portion, having a top located on an upper surface of the first insulating film.
1 . A semiconductor device comprising:
a first electrode;
a first semiconductor region of a first conductivity type disposed above the first electrode and electrically connected to the first electrode;
a second semiconductor region of a second conductivity type disposed on the first semiconductor region;
a third semiconductor region of the first conductivity type disposed on the second semiconductor region;
a second electrode disposed in the first semiconductor region via a first insulating film;
a third electrode facing the second semiconductor region via a second insulating film in a second direction perpendicular to a first direction directed from the second semiconductor region toward the third semiconductor region;
a fourth electrode having a portion adjacent to a part of the second semiconductor region and the third semiconductor region in the second direction, and electrically connected to the second electrode, the second semiconductor region, and the third semiconductor region; and
a fifth electrode disposed in the first insulating film, having a bottom located closer to the first electrode than a bottom of the portion of the fourth electrode, having a top located on an upper surface of the first insulating film, and electrically connected to the fourth electrode, wherein
a first distance from an upper surface of the first electrode to a bottom of the fifth electrode is smaller than a second distance from the upper surface of the first electrode to a bottom of the third electrode, and
a difference between the first distance and the second distance is equal to or less than a length of the third electrode in the first direction.
2 . The semiconductor device according to claim 1 , wherein the fifth electrode is not in contact with the portion of the fourth electrode.
3 . The semiconductor device according to claim 2 , wherein the fifth electrode is made of the same material as the portion of the fourth electrode.
4 . The semiconductor device according to claim 1 , wherein the fifth electrode is in contact with the portion of the fourth electrode.
5 . The semiconductor device according to claim 4 , wherein the fifth electrode is made of the same material as the portion of the fourth electrode.
6 . The semiconductor device according to claim 4 , wherein a first distance from an upper surface of the first electrode to a bottom of the fifth electrode is smaller than a second distance from the upper surface of the first electrode to a bottom of the third electrode.
7 . The semiconductor device according to claim 1 , wherein a thickness of the first insulating film between the fifth electrode and a semiconductor portion including the first semiconductor region and the second semiconductor region decreases in a direction from the first electrode toward the portion of the fourth electrode.
8 . The semiconductor device according to claim 7 , wherein the fifth electrode is in contact with the portion of the fourth electrode.
9 . The semiconductor device according to claim 7 , wherein a first distance from an upper surface of the first electrode to a bottom of the fifth electrode is smaller than a second distance from the upper surface of the first electrode to a bottom of the third electrode.
10 . The semiconductor device according to claim 1 , wherein the fifth electrode is made of the same material as the portion of the fourth electrode.
11 . The semiconductor device according to claim 1 , wherein the fifth electrode is made of the same material as the second electrode.
12 . The semiconductor device according to claim 1 , wherein
the second electrode and the fifth electrode are arranged in parallel in a stripe shape on a plane perpendicular to the first direction,
a pair of fifth electrodes, including the fifth electrode, is provided in the semiconductor device, the pair of fifth electrodes being disposed so as to sandwich the second electrode therebetween, and
an outermost end of the fifth electrodes in a longitudinal direction and an outermost end of the third electrode in the longitudinal direction are aligned in the second direction, or the outermost end of the fifth electrode extends outward with respect to the outermost end of the third electrode in the longitudinal direction.
13 . The semiconductor device according to claim 1 , wherein
the fifth electrode is disposed so as to surround the second electrode on a plane perpendicular to the first direction, and
an outermost end of the fifth electrode in a longitudinal direction and an outermost end of the third electrode in the longitudinal direction are aligned in the second direction, or the outermost end of the fifth electrode extends outward with respect to the outermost end of the third electrode in the longitudinal direction.
14 . The semiconductor device according to claim 1 , wherein
the second electrode, the fifth electrode, and the portion of the fourth electrode are disposed in a concentric polygonal shape or a concentric circular shape around the second electrode on a plane perpendicular to the first direction,
the second electrode is disposed at a center in the first insulating film,
the fifth electrode is disposed in the first insulating film so as to surround the second electrode, and
the portion of the fourth electrode is disposed so as to surround the fifth electrode.
15 . The semiconductor device according to claim 14 , wherein
the third electrode is formed in a lattice shape, a hexagonal shape, or a shape in which intersections of the third electrode do not overlap with each other in the second direction or in a third direction orthogonal to the first direction and the second direction on a plane perpendicular to the first direction, and
the second electrode, the fifth electrode, and the portion of the fourth electrode are disposed in a void formed by the third electrode.
16 . The semiconductor device according to claim 14 , wherein
on a plane perpendicular to the first direction,
the third electrode is formed in a lattice shape,
a boundary between the first insulating film and a semiconductor portion including the first semiconductor region and the second semiconductor region is disposed in a circular shape,
the fifth electrode is disposed in a square shape, and
the portion of the fourth electrode is disposed in a circular shape along the boundary.
17 . A semiconductor device comprising:
a first electrode;
a first semiconductor region of a first conductivity type disposed above the first electrode and electrically connected to the first electrode;
a second semiconductor region of a second conductivity type disposed on the first semiconductor region;
a third semiconductor region of the first conductivity type disposed on the second semiconductor region;
a second electrode disposed in the first semiconductor region via a first insulating film;
a third electrode facing the second semiconductor region via a second insulating film in a second direction perpendicular to a first direction directed from the second semiconductor region toward the third semiconductor region;
a fourth electrode having a portion adjacent to a part of the second semiconductor region and the third semiconductor region in the second direction, and electrically connected to the second electrode, the second semiconductor region, and the third semiconductor region; and
a fifth electrode disposed in the first insulating film, having a bottom located closer to the first electrode than a bottom of the portion of the fourth electrode, having a top located on an upper surface of the first insulating film, and electrically connected to the fourth electrode, wherein
the fifth electrode is in contact with the portion of the fourth electrode,
a first distance from an upper surface of the first electrode to a bottom of the fifth electrode is smaller than a second distance from the upper surface of the first electrode to a bottom of the third electrode, and
a difference between the first distance and the second distance is equal to or less than a length of the third electrode in the first direction.
18 . A semiconductor device comprising:
a first electrode;
a first semiconductor region of a first conductivity type disposed above the first electrode and electrically connected to the first electrode;
a second semiconductor region of a second conductivity type disposed on the first semiconductor region;
a third semiconductor region of the first conductivity type disposed on the second semiconductor region;
a second electrode disposed in the first semiconductor region via a first insulating film;
a third electrode facing the second semiconductor region via a second insulating film in a second direction perpendicular to a first direction directed from the second semiconductor region toward the third semiconductor region;
a fourth electrode having a portion adjacent to a part of the second semiconductor region and the third semiconductor region in the second direction, and electrically connected to the second electrode, the second semiconductor region, and the third semiconductor region; and
a fifth electrode disposed in the first insulating film, having a bottom located closer to the first electrode than a bottom of the portion of the fourth electrode, having a top located on an upper surface of the first insulating film, and electrically connected to the fourth electrode, wherein
a thickness of the first insulating film between the fifth electrode and a semiconductor portion including the first semiconductor region and the second semiconductor region decreases from the first electrode side toward the portion of the fourth electrode,
a first distance from an upper surface of the first electrode to a bottom of the fifth electrode is smaller than a second distance from the upper surface of the first electrode to a bottom of the third electrode, and
a difference between the first distance and the second distance is equal to or less than a length of the third electrode in the first direction.