SEMICONDUCTOR COMPONENT HAVING A SPACE SAVING EDGE STRUCTURE

• US 20080042172A1
• Filed: 08/03/2007
• Published: 02/21/2008
• Est. Priority Date: 08/03/2006
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Geissler, Christian, Hirler, Franz, Siemieniec, Ralf
• Granted Patent: US 8,080,858 B2
• Time in Patent Office: Days
• US Class Current: 257/288
• CPC Class Codes: H01L 29/0615 by the doping profile or the shape or the arrangement of the PN junction, or with supplementary regions, e.g. junction termination extension [JTE] LDD or drain offset regions H01L29/7833
• CPC Class Codes: H01L 29/0623 Buried supplementary region, e.g. buried guard ring multi-RESURF H01L29/0634
• CPC Class Codes: H01L 29/0653 adjoining the input or output region of a field-effect device, e.g. the source or drain region
• CPC Class Codes: H01L 29/0661 specially adapted for altering the breakdown voltage by removing semiconductor material at, or in the neighbourhood of, a reverse biased junction, e.g. by bevelling, moat etching, depletion etching
• CPC Class Codes: H01L 29/404 Multiple field plate structures
• CPC Class Codes: H01L 29/407 Recessed field plates, e.g. trench field plates, buried field plates
• CPC Class Codes: H01L 29/42376 characterised by the length or the sectional shape
• CPC Class Codes: H01L 29/66734 with a step of recessing the gate electrode, e.g. to form a trench gate electrode
• CPC Class Codes: H01L 29/7397 and a gate structure lying on a slanted or vertical surface or formed in a groove, e.g. trench gate IGBT
• CPC Class Codes: H01L 29/7811 with an edge termination structure guard regions per se H01L29/0619; field plates per se H01L29/402
• CPC Class Codes: H01L 29/7813 with trench gate electrode, e.g. UMOS transistors trench gate electrodes per se H01L29/4236
• CPC Class Codes: H01L 29/861 Diodes
• CPC Class Codes: H01L 29/872 Schottky diodes
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A Semiconductor component having a space saving edge structure is disclosed. One embodiment provides a first side, a second side, an inner region, an edge region adjoining the inner region in a lateral direction of the semiconductor body, and a first semiconductor layer extending across the inner region and the edge region and having a basic doping of a first conductivity type. At least one active component zone of a second conductivity type, which is complementary to the first conductivity type, is disposed in the inner region in the first semiconductor layer. An edge structure is disposed in the edge region and includes at least one trench extending from the first side into the semiconductor body. An edge electrode is disposed in the trench, a dielectric layer is disposed in the trench between the edge electrode and the semiconductor body, a first edge zone of the second conductivity type adjoin the trench and are at least partially disposed below the trench.

Claims

1. Semiconductor component comprising:

a semiconductor body comprising a first side, a second side, an inner region, an edge region adjoining the inner region in a lateral direction of the semiconductor body, and a first semiconductor layer extending across the inner region and the edge region and having a basic doping of a first conductivity type;

at least one active component zone of a second conductivity type, which is complementary to the first conductivity type, being disposed in the inner region in the first semiconductor layer; and

an edge structure disposed in the edge region and comprising at least one trench extending from the first side into the semiconductor body, an edge electrode disposed in the trench, a dielectric layer disposed in the trench between the edge electrode and the semiconductor body, a first edge zone of the second conductivity type adjoining the trench and being at least partially disposed below the trench.

2. The semiconductor component of claim 1, comprising a second edge zone being separated from the first edge zone and laterally adjoining the at least one trench and adjoining the first side.

3. The semiconductor component of claims 1, wherein the first edge zone may be completely depleted or may be depleted except for an area having dimensions smaller than a lateral width of the edge trench.

4. The semiconductor component of claim 1, being formed as a MOS transistor and comprising in the inner region of the semiconductor body:

a source zone of a first conductivity type, a drift zone of the first conductivity type, and a body zone of the second conductivity type being disposed between the source zone and the drift zone; and

at least one gate electrode being disposed adjacent to the body zone and being insulated against the body zone by a gate dielectric.

5. The semiconductor component of claim 4, wherein the at least one gate electrode is disposed in a trench, which starting from the first side extends into the semiconductor body.

6. The semiconductor component of claim 5, wherein a field electrode is disposed in the trench of the gate electrode, with the field electrode extending deeper into the semiconductor body than the gate electrode.

7. The semiconductor component of claim 1, wherein the edge electrode is electrically coupled to a source zone.

8. The semiconductor component of claim 1, in which the edge electrode is electrically coupled to a semiconductor zone, with the component zone being doped complementary to a basic doping of the semiconductor layer and being disposed between the edge trench and the inner region.

9. The semiconductor component of claim 8, in which the semiconductor zone that is doped complementary to the basic doping adjoins the edge trench.

10. The semiconductor component of claim 1, further comprising:

at least two trenches with edge electrodes, with the trenches being disposed distant to each other in a lateral direction of the semiconductor body; and

a number of first edge zones corresponding to the number of trenches.

11. The semiconductor component of claim 10, comprising a number of second edge zones corresponding to the number of trenches, with each of the second edge zones adjoining one edge trench in a direction opposite to the direction of the inner region.

12. The semiconductor component of claim 11, in which each of the second edge zones are disposed between two trenches and extend in a lateral direction from trench to trench.

13. Semiconductor component comprising:

a semiconductor body comprising a first side, a second side, an inner region, an edge region adjoining the inner region in a lateral direction of the semiconductor body, and a first semiconductor layer extending across the inner region and the edge region and having a basic doping of a first conductivity type;

at least one active component zone of a second conductivity type, which is complementary to the first conductivity type, and being disposed in the inner region in the first semiconductor layer; and

an edge structure disposed in the edge region and comprising at least one trench extending from the first side into the semiconductor body, a dielectric layer filling the trench, and a first edge zone of the second conductivity type adjoining the at least one trench, being disposed at least partially below the trench, and having a doping which is selected such that it may be depleted completely or except for a region having dimensions smaller than a lateral width of the edge trench, when applying a blocking voltage to a semiconductor junction formed between the active component zone and a zone of the semiconductor layer having the basic doping.

14. The semiconductor component of claim 13, further comprising:

a second edge zone separated from the first edge zone and adjoining the at least one trench in a lateral direction and adjoining the first side.

15. The semiconductor component of claim 13, being formed as a MOS transistor and comprising in the inner region of the semiconductor body:

a source zone of a first conductivity type, a drift zone of the first conductivity type and a body zone of the second conductivity type being disposed between the source zone and the drift zone; and

at least one gate electrode being disposed adjacent to the body zone and being insulated against the body zone by a gate dielectric.

16. The semiconductor component of claim 15, wherein the at least one gate electrode is disposed in a trench, which starting from the first side extends into the semiconductor body.

17. The semiconductor component of claim 16, wherein a field electrode is disposed in the trench of the gate electrode, with the field electrode extending deeper into the semiconductor body than the gate electrode.

18. The semiconductor component of claim 14, comprising:

at least two trenches being disposed distant to each other in a lateral direction and being filled with a dielectric layer; and

a number of edge zones corresponding to a number of trenches.

19. The semiconductor component of claim 18, further comprising a number of second edge zones corresponding to the number of trenches.

20. The semiconductor component of claim 19, wherein each of the second edge zones being disposed between two trenches and extending in a lateral direction from trench to trench.

21. The semiconductor component of claim 17, wherein the edge trench in a vertical direction of the semiconductor body extends less deep into the semiconductor body than the trench with the field electrode.

22. The semiconductor component of claim 14, wherein the second edge zone may not be depleted completely.

25. The semiconductor component of claim 13, wherein the semiconductor layer comprises a first partial layer and a second partial layer having a lower doping concentration than the first partial layer, and wherein the second component zone is completely disposed in the second partial layer.

26. The semiconductor component of claim 17, wherein the at least one edge trench in vertical direction extends deeper into the semiconductor body than the trench with the field electrode.

23. The semiconductor component of 13, wherein the semiconductor layer comprises a first partial layer and a second partial layer having a lower doping concentration than the first partial layer, with the at least one edge trench extending in to the second partial layer.

24. The semiconductor component of claim 23, wherein the trench with the field electrode extends into the second partial layer.