Integrated circuit including lateral insulated gate field effect transistor

Patent metadata

Field	Value
Publication number	US-9899367-B2
Application number	US-201615153276-A
Country	US
Kind code	B2
Filing date	May 12, 2016
Priority date	May 15, 2015
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

An embodiment of an integrated circuit includes a minimum lateral dimension of a semiconductor well at a first surface of a semiconductor body. The integrated circuit further includes a first lateral DMOSFET having a load path electrically coupled to a load pin. The first lateral DMOSFET is configured to control a load current through a load element electrically coupled to the load pin. A minimum lateral dimension of a drain region of the first lateral DMOSFET at the first surface of the semiconductor body is more than 50% greater than the minimum lateral dimension.

First claim

What is claimed is:

1. An integrated circuit, comprising:
a semiconductor well having a minimum width at a first surface of a semiconductor body; and
a first lateral DMOSFET comprising a load path electrically coupled to a load pin, the first lateral DMOSFET being configured to control a load current through a load element electrically coupled to the load pin,
wherein a minimum width of a drain region of the first lateral DMOSFET at the first surface of the semiconductor body is more than 50% greater than the minimum width of the semiconductor well at the first surface of the semiconductor body,
wherein the semiconductor well is spaced apart from the drain region of the first lateral DMOSFET and does not form part of the first lateral DMOSFET.

2. The integrated circuit of claim 1 , wherein the lateral DMOSFET further comprises a dielectric structure extending into the semiconductor body at the first surface between the drain region and a channel region.

3. The integrated circuit of claim 2 , wherein the dielectric structure is a shallow trench isolation structure or a LOCOS structure.

4. The integrated circuit of claim 2 , wherein the dielectric structure and a gate structure of the lateral DMOSFET partly overlap at the first surface.

5. The integrated circuit of claim 1 , further comprising at least two contact plugs or at least two contact stripes arranged one after another along a lateral direction, wherein the lateral direction extends from a source region to the drain region, and the least two contact plugs or at least two contact stripes are electrically connected to the drain region.

6. The integrated circuit of claim 1 , further comprising a second lateral DMOSFET, wherein a minimum width of a drain region of the second lateral DMOSFET at the first surface of the semiconductor body equals the minimum width of the semiconductor well at the first surface of the semiconductor body.

7. The integrated circuit of claim 1 , further comprising a body region including at least first and second body sub-regions, the first body sub-region being buried within the semiconductor body.

8. The integrated circuit of claim 7 , wherein a first lateral distance between the first body sub-region and the drain region is smaller than a second lateral distance between the second body sub-region and the drain region.

9. The integrated circuit of claim 8 , further comprising a dielectric structure extending into the semiconductor body at the first surface between the drain region and a channel region, wherein a projection area of the first body sub-region onto the first surface and a projection area of the dielectric structure onto the first surface overlap.

10. The integrated circuit of claim 9 , wherein a minimum vertical distance between the dielectric structure and the first body sub-region is smaller than the minimum width of the drain region of the first lateral DMOSFET at the first surface of the semiconductor body.

11. The integrated circuit of claim 1 , wherein a specified maximum drain to source voltage of the first lateral DMOSFET ranges between 10 V and 800 V.

12. The integrated circuit of claim 1 , wherein at least one of a source terminal and a drain terminal of the first lateral DMOSFET is electrically connected to a pin of the integrated circuit.

13. The integrated circuit of claim 12 , wherein the pin is the load pin and/or a supply pin.

14. The integrated circuit of claim 1 , further comprising a trigger circuit configured to switch the first lateral DMOSFET in an on-state when a voltage between source and drain terminals of the first lateral DMOSFET exceeds a trigger voltage.

15. The integrated circuit of claim 14 , wherein the trigger circuit comprises at least one series connection of Zener diodes.

16. The integrated circuit of claim 14 , wherein the trigger circuit comprises at least one third lateral DMOSFET, wherein a minimum width of a drain region of the at least one third lateral DMOSFET at the first surface of the semiconductor body equals the minimum width of the semiconductor well at the first surface of the semiconductor body.

17. A load system, comprising:
an integrated circuit, comprising:
a semiconductor well having a minimum width at a first surface of a semiconductor body; and
a first lateral DMOSFET comprising a load path electrically coupled to a load pin, the first lateral DMOSFET being configured to control a load current through a load element electrically coupled to the load pin,
wherein a minimum width of a drain region of the first lateral DMOSFET at the first surface of the semiconductor body is more than 50% greater than the minimum width of the semiconductor well at the first surface of the semiconductor body,
wherein the semiconductor well is spaced apart from the drain region of the first lateral DMOSFET and does not form part of the first lateral DMOSFET; and
a load electrically coupled to the load pin.

18. The load system of claim 17 , wherein the load is one of a motor, an inductive load, a resistive load, a capacitive load, and a lamp.

19. The load system of claim 17 , wherein the lateral DMOSFET further comprises a dielectric structure extending into the semiconductor body at the first surface between the drain region and a channel region.

20. The load system of claim 17 , wherein the integrated circuit further comprises a body region including at least first and second body sub-regions, the first body sub-region being buried within the semiconductor body.

21. The integrated circuit of claim 1 , wherein the semiconductor well and the drain region of the first lateral DMOSFET have the same conductivity type.

22. The integrated circuit of claim 21 , wherein the semiconductor well and the drain region of the first lateral DMOSFET are n-doped.

23. The integrated circuit of claim 1 , wherein the minimum width of the semiconductor well at the first surface of the semiconductor body is a minimum photolithographic width.

24. The load system of claim 17 , wherein the semiconductor well and the drain region of the first lateral DMOSFET have the same conductivity type.

25. The load system of claim 24 , wherein the semiconductor well and the drain region of the first lateral DMOSFET are n-doped.

26. The load system of claim 17 , wherein the minimum width of the semiconductor well at the first surface of the semiconductor body is a minimum photolithographic width.

27. An integrated circuit, comprising:
a semiconductor well having a minimum width at a first surface of a semiconductor body; and
a first lateral DMOSFET comprising a load path electrically coupled to a load pin and a dielectric structure extending into the semiconductor body at the first surface between the drain region and a channel region, the first lateral DMOSFET being configured to control a load current through a load element electrically coupled to the load pin,
wherein a minimum width of a drain region of the first lateral DMOSFET at the first surface of the semiconductor body is more than 50% greater than the minimum width of the semiconductor well at the first surface of the semiconductor body.

Assignees

• Infineon Technologies Ag

Inventors

• Esmark Kai
• Cao Yiqun
• Dibra Donald

Classifications

• H10D84/835

  comprising LDMOS · CPC title

• H01L29/0649

  Electricity · mapped topic

• H01L27/0255 Primary

  Electricity · mapped topic

• H01L29/1095

  Electricity · mapped topic

• H01L27/0886

  Electricity · mapped topic