Semiconductor device with heterojunction

• US 20050224838A1
• Filed: 04/01/2005
• Published: 10/13/2005
• Est. Priority Date: 04/13/2004
• Status: Abandoned Application

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Tanaka, Hideaki, Hoshi, Masakatsu, Hayashi, Tetsuya
• Application Number:
  US11/095,528
• Publication Number:
  US 20050224838A1
• Time in Patent Office: Days
• US Class Current: 257/187
• CPC Class Codes: H01L 29/165 in different semiconductor regions , e.g. heterojunctions
• CPC Class Codes: H01L 29/267 in different semiconductor regions , e.g. heterojunctions H01L29/263 takes precedence
• CPC Class Codes: H01L 29/7827 Vertical transistors H01L29/7802, H01L29/78642 take precedence
• CPC Class Codes: H01L 29/861 Diodes

Abstract

An aspect of the present invention provides a semiconductor device that includes a semiconductor base essentially made of a first semiconductor material of a first conductivity type, a hetero-semiconductor region essentially made of a second semiconductor material whose band gap is different from that of the first semiconductor material, formed on the semiconductor base, and forming a heterojunction with the semiconductor base, a cathode electrode formed in contact with the semiconductor base, and an anode electrode formed in contact with the hetero-semiconductor region, wherein the first semiconductor material is a silicon-carbide (SiC) single crystal and the heterojunction is formed on a {0001-} crystal face of the silicon-carbide single crystal.

Claims

1. A semiconductor device comprising:

a semiconductor base essentially made of a first semiconductor material of a first conductivity type;

a hetero-semiconductor region essentially made of a second semiconductor material whose band gap is different from that of the first semiconductor material, formed on the semiconductor base, and forming a heterojunction with the semiconductor base;

a cathode electrode formed in contact with the semiconductor base; and

an anode electrode formed in contact with the hetero-semiconductor region,

wherein the first semiconductor material is a silicon-carbide (SiC) single crystal and the heterojunction is formed on a {0001-} crystal face of the silicon-carbide single crystal.

2. The semiconductor device as claimed in claim 1, wherein the hetero-semiconductor region is of the first conductivity type.

3. The semiconductor device as claimed in claim 1, further comprising:

a second hetero-semiconductor region essentially made of the second semiconductor material whose band gap is different from that of the first semiconductor material, the second hetero-semiconductor region being formed on the semiconductor base and forming a heterojunction with the semiconductor base.

4. The semiconductor device as claimed in claim 1, further comprising:

a second hetero-semiconductor region essentially made of the second semiconductor material whose band gap is different from that of the first semiconductor material the second hetero-semiconductor region being formed on the hetero-semiconductor region and having a higher impurity concentration than the hetero-semiconductor region.

5. The semiconductor device as claimed in claim 1, further comprising:

an impurity introduced region essentially made of silicon carbide of a second conductivity type and formed in a part of the surface of the semiconductor base.

6. The semiconductor device as claimed in claim 1, wherein the semiconductor device has a mesa structure.

7. The semiconductor device as claimed in claim 1, wherein:

the second semiconductor material is selected from the group consisting of a silicon single crystal and a silicon polycrystal.

8. A semiconductor device comprising:

a drain region formed from a semiconductor base made of a first semiconductor material of a first conductivity type;

a base region of a second conductivity type, base region in contact with the drain region;

a source region of the first conductivity type, the source region in contact with the base region;

a source electrode formed in contact with the source region and the base region;

a drain electrode formed in contact with the drain region; and

a hetero-semiconductor region made of a second semiconductor material that has a different band gap from the first semiconductor material forms a heterojunction with the drain region, and is in contact with the source electrode, wherein;

the first semiconductor material is a silicon-carbide single crystal and the heterojunction is formed on a {0001-} crystal face of the silicon-carbide single crystal.

9. The semiconductor device as claimed in claim 8, wherein the hetero-semiconductor region is of the first conductivity type.

10. The semiconductor device as claimed in claim 8, further comprising:

a second hetero-semiconductor region essentially made of the second semiconductor material whose band gap is different from that of the first semiconductor material, the second hetero-semiconductor region being formed on the semiconductor base and forming a heterojunction with the semiconductor base.

11. The semiconductor device as claimed in claim 8, further comprising:

a second hetero-semiconductor region essentially made of the second semiconductor material whose band gap is different from that of the first semiconductor material, the second hetero-semiconductor region being formed on the hetero-semiconductor region and having a higher impurity concentration than the hetero-semiconductor region.

12. The semiconductor device as claimed in claim 8, wherein:

the second semiconductor material is selected from the group consisting of a silicon single crystal and a silicon polycrystal.

13. A semiconductor device comprising:

a semiconductor base essentially made of a first semiconductor material of a first conductivity type;

a hetero-semiconductor region formed on the semiconductor base and essentially made of a second semiconductor material that has a different band gap from the first semiconductor material and forms a heterojunction with the semiconductor base;

a gate electrode formed on a gate insulating film adjacent to the heterojunction between the semiconductor base and the hetero-semiconductor region;

a source electrode formed in contact with the hetero-semiconductor region; and

a drain electrode formed in contact with the semiconductor base, wherein;

the first semiconductor material is a silicon-carbide single crystal and the heterojunction is formed on a {0001-} crystal face of the silicon-carbide single crystal.

14. The semiconductor device as claimed in claim 13, wherein the hetero-semiconductor region is of the first conductivity type.

15. The semiconductor device as claimed in claim 13, further comprising:

a second hetero-semiconductor region essentially made of the second semiconductor material whose band gap is different from that of the first semiconductor material, the second hetero-semiconductor region being formed on the semiconductor base and forming a heterojunction with the semiconductor base.

16. The semiconductor device as claimed in claim 13, further comprising:

a second hetero-semiconductor region essentially made of the second semiconductor material whose band gap is different from that of the first semiconductor material, the second hetero-semiconductor region being formed on the hetero-semiconductor region and having a higher impurity concentration than the hetero-semiconductor region.

17. The semiconductor device as claimed in claim 13, wherein:

the second semiconductor material is selected from the group consisting of a silicon single crystal and a silicon polycrystal.

19. The semiconductor device as claimed in claim 13, wherein the hetero-semiconductor region is of the first conductivity type.

20. The semiconductor device as claimed in claim 13, wherein:

the second semiconductor material is selected from the group consisting of a silicon single crystal and a silicon polycrystal.

18. A semiconductor device comprising:

a semiconductor base made of a first semiconductor material of a first conductivity type;

a hetero-semiconductor region formed on the semiconductor base and made of a second semiconductor material that has a different band gap from the first semiconductor material and forms a heterojunction with the semiconductor base;

a trench formed through the hetero-semiconductor region to reach the semiconductor base;

a gate electrode formed on a gate insulating film in the trench;

a source electrode formed in contact with the hetero-semiconductor region; and

a drain electrode formed in contact with the semiconductor base, wherein;

the first semiconductor material is a silicon-carbide single crystal and the heterojunction is formed on a {0001-} crystal face of the silicon-carbide single crystal.