Forming recombination centers in a semiconductor device

Patent metadata

Field	Value
Publication number	US-10347491-B2
Application number	US-201715850041-A
Country	US
Kind code	B2
Filing date	Dec 21, 2017
Priority date	Dec 22, 2016
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

Disclosed is a method. The method includes implanting recombination center particles into a semiconductor body via at least one contact hole in an insulation layer formed on top of the semiconductor body, forming a contact electrode electrically connected to the semiconductor body in the at least one contact hole, and annealing the semiconductor body to diffuse the recombination center particles in the semiconductor body. Forming the contact electrode includes forming a barrier layer on sections of the semiconductor body uncovered in the at least one contact hole, wherein the barrier layer is configured to inhibit the recombination center particles from diffusing out of the semiconductor body.

First claim

What is claimed is:

1. A method, comprising: implanting recombination center particles into a semiconductor body via at least one contact hole in an insulation layer formed on top of the semiconductor body; forming a contact electrode electrically connected to the semiconductor body in the at least one contact hole; and annealing the semiconductor body to diffuse the recombination center particles in the semiconductor body, wherein forming the contact electrode comprises forming a barrier layer on sections of the semiconductor body uncovered in the at least one contact hole, wherein the barrier layer is configured to inhibit the recombination center particles from diffusing out of the semiconductor body, wherein the barrier layer comprises at least one layer, and wherein the at least one layer comprises at least one of titanium (Ti), titanium nitride (TiN), tantalum (Ta), tantalum nitride (TaN), titanium tungsten alloy (TiW), and titanium tungsten nitride (TiWN).

2. The method of claim 1 , wherein forming the contact electrode further comprises:
forming at least one electrode layer on the barrier layer.

3. The method of claim 2 , wherein the annealing occurs after forming the barrier layer and before forming the at least one electrode layer.

4. The method of claim 2 , wherein the at least one electrode layer comprises a material selected from the group consisting of:
tungsten (W);
an aluminum copper alloy (AlCu); and
an aluminum silicon copper alloy (AlSiCu).

5. The method of claim 1 , wherein the annealing occurs before forming the barrier layer.

6. The method of claim 1 , further comprising:
forming a sacrificial layer at least on the insulation layer before implanting the recombination center particles; and
removing the sacrificial layer before forming the contact electrode.

7. The method of claim 6 , wherein forming the sacrificial layer comprises forming the sacrificial layer on the insulation layer and on the semiconductor body in the contact hole.

8. The method of claim 6 , wherein the sacrificial layer comprises an oxide layer.

9. The method of claim 1 , further comprising:
forming an implantation mask on the insulation layer before implanting the recombination center particles; and
removing the implantation mask after implanting the recombination center particles.

10. The method of claim 1 , wherein the semiconductor body comprises a contact hole adjoining the at least one contact hole in the insulation layer, and wherein the recombination center particles are implanted into the contact hole of the semiconductor body.

11. The method of claim 1 , further comprising:
after implanting the recombination center particles and before forming the contact electrode, forming a contact hole in the semiconductor body adjoining the at least one contact hole in the insulation layer.

12. The method of claim 11 , wherein forming the contact hole in the semiconductor body comprises etching the semiconductor body using the insulation layer as an etch mask.

13. The method of claim 1 , wherein the semiconductor body comprises:
a drift region of a first doping type:
a body region of a second doping type complementary to the first doping type and adjoining the drift region; and
a source region of the first doping type separated from the drift region by the body region,
wherein forming the contact electrode comprises forming the contact electrode to be connected to the source region and the body region.

14. The method of claim 13 , wherein the semiconductor body further comprises a drain region of the first doping type that is more highly doped than the drift region and separated from the body region by the drift region.

15. The method of claim 13 , wherein the semiconductor body further comprises a collector region of the second doping type that is more highly doped than the drift region and separated from the body region by the drift region.

16. The method of claim 1 , wherein the semiconductor body comprises:
a base region of a first doping type; and
a first emitter region of a second doping type complementary to the first doping type,
wherein forming the contact electrode comprises forming the contact electrode to be electrically connected to the first emitter region.

17. The method of claim 1 , wherein annealing the semiconductor body comprises an RTA process.

18. The method of claim 1 , wherein annealing the semiconductor body comprises a furnace process.

19. The method of claim 1 , wherein the recombination center particles comprise atoms or ions of one or more chemical elements selected from the group consisting of:
platinum (Pt);
gold (Au);
palladium (Pd);
iridium (Ir);
silver (Ag);
copper (Cu);
mercury (Hg); and
rhenium (Re).

20. A method, comprising: implanting recombination center particles into a semiconductor body via at least one contact hole in an insulation layer formed on top of the semiconductor body; forming a contact electrode electrically connected to the semiconductor body in the at least one contact hole; and annealing the semiconductor body to diffuse the recombination center particles in the semiconductor body, wherein forming the contact electrode comprises forming a barrier layer on sections of the semiconductor body uncovered in the at least one contact hole, wherein the barrier layer is configured to inhibit the recombination center particles from diffusing out of the semiconductor body, wherein the recombination center particles comprise atoms or ions of one or more chemical elements selected from the group consisting of: platinum (Pt); gold (Au); palladium (Pd); iridium (Ir); silver (Ag); copper (Cu); mercury (Hg); and rhenium (Re).

Assignees

• Infineon Technologies Austria Ag

Inventors

• Jantscher Wolfgang
• Binter Alexander
• Blank Oliver
• Fischer Petra
• Joshi Ravi Keshav
• Pekoll Kurt
• Pippan Manfred
• Riegler Andreas
• Schustereder Werner
• Steinbrenner Juergen
• Syed Waqas Mumtaz

Classifications

• H10P95/90

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P50/691

  for Group V materials or Group III-V materials · CPC title

• H10P36/03

  within silicon bodies · CPC title

• H10P30/209

  in silicon to make buried insulating layers · CPC title

• H10W20/0765

  the thin functional dielectric layers being temporary, e.g. sacrificial layers · CPC title