Semiconductor device and method of manufacturing the same

Claim 2

The semiconductor device according to claim 1, wherein said gate structure further includes electrically good-conductive bodies each being corresponding to respective one of said semiconductor regions.

Claim 3

The semiconductor device according to claim 2, wherein each of said electrically good-conductive bodies is substantially completely surrounded by respective one of said semiconductor regions.

Claim 4

The semiconductor device according to claim 2, wherein each of said electrically good-conductive bodies is provided on a surface of respective one of said semiconductor regions.

Claim 5

The semiconductor device according to claim 2, wherein said electrically good-conductive bodies are made of such a material that constitutes a Schottky junction with said second semiconductor substrate, and are arranged such that end portions thereof are brought into contact with said first surface of the second semiconductor substrate.

Claim 6

The semiconductor device according to claim 1 or 2, wherein said recessed portions formed in said first main surface of said first semiconductor substrate are completely filled with said gate structure.

Claim 7

The semiconductor device according to claim 6, wherein said first main surface of said second semiconductor substrate is joined to said first main surface of said first semiconductor substrate and an upper surface of said gate structure.

Claim 8

The semiconductor device according to claim 7, wherein a semiconductor region having the same conductivity type as that of said semiconductor regions of said gate structure is provided in said first main surface of said second semiconductor substrate such that said semiconductor region of said second semiconductor substrate is in contact with at least said gate structure formed in said first main surface of said first semiconductor substrate.

Claim 9

The semiconductor device according to claim 8, wherein said semiconductor region having the same conductivity type as that of said semiconductor regions of said gate structure is provided in an entire first main surface of said second semiconductor substrate.

Claim 10

The semiconductor device according to claim 1 or 2, wherein said recessed portions formed in said first main surface of said first semiconductor substrate is partially filled with said gate structure while leaving a space between said gate structure and said first main surface of said second semiconductor substrate.

Claim 11

The semiconductor device according to claim 1, wherein a low-resistance contact region is provided in joined surfaces of said first and second semiconductor substrates at a position other than said gate structure.

Claim 13

The method of manufacturing a semiconductor device according to claim 12, wherein the step of forming said gate structure within said recessed portions provided in said first main surface of said first semiconductor substrate comprises the sub-steps of forming a semiconductor layer doped with impurities of the opposite conductivity type on said first main surface of said first semiconductor substrate, in which said recessed portions have already been provided, by chemical vapor deposition; and partially removing said semiconductor layer until said first main surface of said semiconductor substrate is exposed.

Claim 14

The method of manufacturing a semiconductor device according to claim 12, wherein the step of forming said gate structure within said recessed portions provided in said first main surface of said first semiconductor substrate comprises the sub-steps of forming a first semiconductor layer doped with impurities of the opposite conductivity type on said first main surface of said first semiconductor substrate, in which said recessed portions have already been provided, by chemical vapor deposition; providing an electrically good-conductive body on said first semiconductor layer within respective one of said recessed portions; forming a second semiconductor layer doped with impurities of the opposite conductivity type on said electrically good-conductive bodies as well as on said first semiconductor layer by chemical vapor deposition; and partially removing said first and second semiconductor layers until said first main surface of said semiconductor substrate is exposed.

Claim 15

The method of manufacturing a semiconductor device according to claim 12, wherein the step of forming said gate structure within said recessed portions provided in said first main surface of said first semiconductor substrate comprises the sub-steps of forming a first semiconductor layer doped with impurities of the opposite conductivity type on said first main surface of said first semiconductor substrate, in which said recessed portions have already been provided, by chemical vapor deposition; forming an electrically good-conductive film on said first semiconductor layer; forming a second semiconductor layer doped with impurities of the opposite conductivity type on said electrically good-conductive film by chemical vapor deposition; and partially removing said first and second semiconductor layers and said electrically good-conductive film until said first main surface of said semiconductor substrate is exposed.

Claim 16

The method of manufacturing a semiconductor device according to claim 12, wherein the step of forming said gate structure within said recessed portions provided in said first main surface of said first semiconductor substrate comprises the sub-steps of forming a semiconductor layer doped with impurities of the opposite conductivity type on said first main surface of said first semiconductor substrate, in which said recessed portions have already been provided, in a manner such that end faces of said semiconductor layer is coplanar with said first main surface of said first semiconductor substrate; and forming an electrically good-conductive film on said semiconductor layer in a manner such that end faces of said electrically good-conductive film is coplanar with said first main surface of said first semiconductor substrate; said method further comprising the step of providing said first main surface of said second semiconductor substrate with a semiconductor region of said opposite conductivity type at least in such position corresponding to said gate structure formed in said first semiconductor substrate so that said electrically good-conductive film of said gate structure is completely surrounded by semiconductor regions having said opposite conductivity type when said first and second semiconductor substrates are joined to each other.

Claim 17

The method of manufacturing a semiconductor device according to claim 16, wherein a semiconductor layer of said opposite conductivity type is provided in the entire of said first main surface of said second semiconductor substrate.