Vertical field effect transistor device having alternating drift regions and compensation regions

Patent metadata

Field	Value
Publication number	US-10164086-B2
Application number	US-201615273400-A
Country	US
Kind code	B2
Filing date	Sep 22, 2016
Priority date	Sep 23, 2015
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A semiconductor device includes a plurality of drift regions of a vertical field effect transistor arrangement arranged in a semiconductor substrate. The plurality of drift regions has a first conductivity type. The semiconductor device further includes a plurality of compensation regions arranged in the semiconductor substrate. The plurality of compensation regions has a second conductivity type. Each drift region of the plurality of drift regions is arranged adjacent to at least one compensation region of the plurality of compensation regions. The semiconductor device further includes a body region of a transistor structure of the vertical field effect transistor arrangement arranged adjacent to a drift region of the plurality of drift regions. The semiconductor device further includes a gate extending substantially vertically along the body region of the transistor structure for controlling a substantially vertical channel region between a first doping region of the transistor structure and the drift region.

First claim

What is claimed is:

1. A semiconductor device, comprising:
a plurality of drift regions of a vertical field effect transistor arrangement arranged in a semiconductor substrate, wherein the plurality of drift regions comprises a first conductivity type;
a plurality of compensation regions arranged in the semiconductor substrate, wherein the plurality of compensation regions comprise a second conductivity type, wherein each drift region of the plurality of drift regions is arranged adjacent to at least one compensation region of the plurality of compensation regions;
a body region of a transistor structure of the vertical field effect transistor arrangement arranged adjacent to a drift region of the plurality of drift regions; and
a gate extending substantially vertically along the body region of the transistor structure for controlling a substantially vertical channel region between a first doping region of the transistor structure and the drift region,
wherein at least part of the gate is formed on at least one sidewall of a gate trench structure located adjacent to the body region of the transistor structure,
wherein the body region of the transistor structure and the first doping region of the transistor structure are located in a portion of the semiconductor substrate located laterally between the gate trench structure and a further gate trench structure of a plurality of gate trench structures comprising gates of transistor structures of the vertical field effect transistor arrangement,
wherein the portion of the semiconductor substrate comprising the body region of the transistor structure and the first doping region of the transistor structure has a lateral dimension smaller than a lateral dimension of the drift region of the transistor structure.

2. The semiconductor device of claim 1 , compensation region of the plurality of compensation regions extends from a bottom of the gate trench structure into the semiconductor substrate.

3. The semiconductor device of claim 1 , wherein the portion of the semiconductor substrate comprising the body region of the transistor structure and the first doping region of the transistor structure has a lateral dimension of between 500 nm and 5 μm.

4. The semiconductor device of claim 1 , further comprising an electrically conductive contact structure forming a short circuit connection between a part of the first doping region of the transistor structure and a part of the body region of the transistor structure.

5. The semiconductor device of claim 4 , wherein the electrically conductive contact structure is in contact with the first doping region of the transistor structure and the body region of the transistor structure within one contact trench of the transistor structure.

6. The semiconductor device of claim 1 , wherein the compensation region and the body region of the transistor structure are separated within the semiconductor substrate by at least one p-n junction.

7. A semiconductor device, comprising:
a plurality of drift regions of a vertical field effect transistor arrangement arranged in a semiconductor substrate, wherein the plurality of drift regions comprises a first conductivity type;
a plurality of compensation regions arranged in the semiconductor substrate, wherein the plurality of compensation regions comprise a second conductivity type, wherein each drift region of the plurality of drift regions is arranged adjacent to at least one compensation region of the plurality of compensation regions;
a body region of a transistor structure of the vertical field effect transistor arrangement arranged adjacent to a drift region of the plurality of drift regions; and
a gate extending substantially vertically along the body region of the transistor structure for controlling a substantially vertical channel region between a first doping region of the transistor structure and the drift region,
wherein at least part of a gate structure forming the gate of the transistor structure is located laterally between at least part of a first doping region contact c e in electrical connection with the first doping region of the transistor structure and at least part of a compensation region contact structure in electrical connection with the compensation region adjacent to the drift region of the transistor structure.

8. The semiconductor device of claim 7 , wherein a contact resistance between the first doping region contact structure and the first doping region of the transistor structure is different from a contact resistance between the compensation region contact structure and the compensation region.

9. The semiconductor device of claim 7 , wherein the compensation region contact structure is in contact with the compensation region within the gate structure.

10. The semiconductor device of claim 7 , wherein the compensation region contact structure is laterally surrounded by at least part of the gate structure.

11. A semiconductor device, comprising:
a plurality of drift regions of a vertical field effect transistor arrangement arranged in a semiconductor substrate, wherein the plurality of drift regions comprises a first conductivity type;
a plurality of compensation regions arranged in the semiconductor substrate, wherein the plurality of compensation regions comprise a second conductivity type, wherein each drift region of the plurality of drift regions is arranged adjacent to at least one compensation region of the plurality of compensation regions;
a body region of a transistor structure of the vertical field effect transistor arrangement arranged adjacent to a drift region of the plurality of drift regions;
a gate extending substantially vertically along the body region of the transistor structure for controlling a substantially vertical channel region between a first doping region of the transistor structure and the drift region; and
an electrically conductive contact structure forming a short circuit connection between a part of the first doping region of the transistor structure and a part of the body region of the transistor structure.

12. The semiconductor device of claim 11 , wherein the electrically conductive contact structure is in contact with the first doping region of the transistor structure and the body region of the transistor structure within one contact trench of the transistor structure.

13. A semiconductor device, comprising:
a drift region of a vertical field effect transistor arrangement arranged in a semiconductor substrate, wherein the drift region comprises a first conductivity type;
a compensation region arranged in the semiconductor substrate and comprising a second conductivity type, wherein the drift region is arranged adjacent to the compensation region;
a body region of a transistor structure of the vertical field effect transistor arrangement arranged adjacent to the drift region, wherein the body region comprises the second conductivity type, wherein the body region has a smaller lateral dimension than that of the drift region so as to not overlap the compensation region; and
a gate extending substantially vertically along the body region for controlling a substantially vertical channel region between a first doping region of the transistor structure and the drift region.

14. The semiconductor device of claim 13 , wherein at least part of a gate structure forming the gate of the transistor structure is located laterally between at least part of a first doping region contact structure in electrical connection with the first doping region and at least part of a compensation region contact structure in electrical connection with the compensation regi

Assignees

• Infineon Technologies Austria Ag

Inventors

• Tegen Stefan
• Manger Dirk

Classifications

• H10P30/204

  into Group IV semiconductors · CPC title

• H10P30/21

  of electrically active species · CPC title

• H01L29/456

  Electricity · mapped topic

• H01L29/7813

  Electricity · mapped topic

• H01L21/26513

  Electricity · mapped topic