Semiconductor device including a contact structure directly adjoining a mesa section and a field electrode

Patent metadata

Field	Value
Publication number	US-9847395-B2
Application number	US-201615201017-A
Country	US
Kind code	B2
Filing date	Jul 1, 2016
Priority date	Jul 3, 2015
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

A semiconductor device includes a gate structure that extends from a first surface into a semiconductor portion and that surrounds a transistor section of the semiconductor portion. A field plate structure includes a field electrode and extends from the first surface into the transistor section. A mesa section of the semiconductor portion separates the field plate structure and the gate structure. A contact structure includes a first portion directly adjoining the mesa section and a second portion directly adjoining the field electrode. The first and second portions include stripes and are directly connected to each other.

First claim

What is claimed is:

1. A semiconductor device, comprising:
a gate structure extending from a first surface into a semiconductor portion and surrounding a transistor section of the semiconductor portion;
a field plate structure extending from the first surface into the transistor section and comprising a field electrode;
a mesa section of the transistor section separating the field plate structure and the gate structure; and
a contact structure comprising a first portion directly adjoining the mesa section and a second portion directly adjoining the field electrode, wherein the first and second portions include stripes and are directly connected to each other.

2. The semiconductor device of claim 1 , wherein the first portion includes stripes forming a closed, polygonal frame in a horizontal cross-section parallel to the first surface.

3. The semiconductor device of claim 1 , wherein the first portion includes stripes forming a closed, regular polygonal frame in a horizontal cross-section parallel to the first surface.

4. The semiconductor device of claim 1 , wherein the first portion includes four stripes forming a closed square frame in a horizontal cross-section parallel to the first surface.

5. The semiconductor device of claim 1 , wherein the first portion forms a closed oval frame in a horizontal cross-section.

6. The semiconductor device of claim 1 , wherein the second portion comprises a stripe extending from the first portion to a vertical projection of the field electrode, and wherein the vertical projection is perpendicular to the first surface.

7. The semiconductor device of claim 6 , wherein the second portion includes a stripe and both end faces of the stripe directly adjoin the first portion.

8. The semiconductor device of claim 1 , wherein the first portion includes at least four straight stripes forming a closed frame, and wherein the second portion extends through an opening of the frame and crosses a center of the opening.

9. The semiconductor device of claim 1 , wherein the first portion is formed at a horizontal distance to the field plate structure.

10. The semiconductor device of claim 1 , wherein the first portion overlaps with a vertical projection of the field plate structure perpendicular to the first surface.

11. The semiconductor device of claim 1 , wherein the mesa section includes body zones forming a first pn junction with a drift structure and second pn junctions with source zones formed between the body zones and the first surface.

12. The semiconductor device of claim 11 , wherein the gate structure includes a gate electrode and a gate dielectric separating the gate electrode from the body zones.

13. The semiconductor device of claim 1 , wherein the gate structure forms a grid and a mesh of the grid includes the transistor section and the field plate structure.

14. The semiconductor device of claim 1 , wherein the first and second portions comprise stripes of uniform width.

15. A semiconductor device, comprising:
gate structures extending from a first surface into a semiconductor portion and defining transistor sections of the semiconductor portion between neighboring ones of the gate structures;
spicular field plate structures extending from the first surface into the transistor sections and including field electrodes;
mesa sections of the transistor sections separating the field plate structures from each other and from the gate structures; and
contact structures each of which comprises a first portion directly adjoining one of the mesa sections and a second portion directly adjoining one of the field electrodes, wherein the first and second portions include stripes.

16. The semiconductor device of claim 15 , wherein the first and second portions are directly connected to each other along a direction horizontal to the first surface.

17. The semiconductor device of claim 15 , wherein the first portions of the contact structures assigned to neighboring ones of the field plate structures in a same transistor section are connected to each other along a longitudinal axis of the first portions.

18. The semiconductor device of claim 15 , wherein the first portions of the contact structures assigned to neighboring ones of the field plate structures in a same transistor section are separated from each other.

19. The semiconductor device of claim 15 , wherein the first and second portions are parallel stripes.

20. An electronic assembly, comprising:
a semiconductor device comprising:
a gate structure including a gate electrode and extending from a first surface into a semiconductor portion and surrounding a transistor section of the semiconductor portion;
a field plate structure extending from the first surface into the transistor section and comprising a field electrode;
a mesa section of the transistor section separating the field plate structure and the gate structure; and
a contact structure comprising a first portion directly adjoining the mesa section and a second portion directly adjoining the field electrode, wherein the first and second portions include stripes and are directly connected to each other; and
a gate driver circuit electrically connected or coupled to the gate electrode.

Assignees

• Infineon Technologies Austria Ag

Inventors

• Laforet David
• Schwarz Elisabeth
• Weissnicht Beate

Classifications

• H10W42/00

  Arrangements for protection of devices (arrangements for thermal protection H10W40/00) · CPC title

• H10W72/00

  Interconnections or connectors in packages · CPC title

• H01L29/7397

  Electricity · mapped topic

• H01L23/585

  Electricity · mapped topic

• H01L29/7813

  Electricity · mapped topic