SEMICONDUCTOR MANUFACTURING METHOD AND SEMICONDUCTOR MANUFACTURING APPARATUS

• US 20160079085A1
• Filed: 06/26/2015
• Published: 03/17/2016
• Est. Priority Date: 09/12/2014
• Status: Active Grant

• Current Assignee: SCREEN Holdings Co., Ltd.
• Original Assignee: SCREEN Holdings Co., Ltd.
• Inventors: Aoyama, Takayuki, Kato, Shinichi
• Granted Patent: US 9,769,880 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/046 using ion implantation
• CPC Class Codes: H01L 21/0485 Ohmic electrodes
• CPC Class Codes: H01L 21/28512 on semiconductor bodies comprising elements of Group IV of the Periodic Table
• CPC Class Codes: H01L 21/67115 mainly by radiation
• CPC Class Codes: H01L 21/67248 Temperature monitoring
• CPC Class Codes: H01L 21/68785 characterised by the mechanical construction of the susceptor, stage or support
• CPC Class Codes: H01L 21/76889 by forming silicides of refractory metals
• CPC Class Codes: H05B 3/0047 for semiconductor manufacture

Abstract

Flash light is emitted from flash lamps to the surface of a semiconductor substrate on which a metal layer has been formed for one second or less to momentarily raise temperature on the surface of the semiconductor substrate including the metal layer and an impurity region to a processing temperature of 1000° C. or more. Heat treatment is performed by emitting flash light to the surface of the semiconductor substrate in a forming gas atmosphere containing hydrogen. By heating the surface of the semiconductor substrate to a high temperature in the forming gas atmosphere for an extremely short time period, contact resistance can be reduced without desorbing hydrogen taken in the vicinity of an interface of a gate oxide film for hydrogen termination.

Claims

1. A semiconductor manufacturing method for forming a contact to a semiconductor substrate, the method comprising the steps of:

(a) implanting ions into a region of the semiconductor substrate to form an impurity region;

(b) forming a metal layer on said impurity region; and

(c) emitting light to said semiconductor substrate on which said metal layer has been formed for one second or less for heating, wherein

said step (c) is performed in a forming gas atmosphere containing hydrogen.

2. The semiconductor manufacturing method according to claim 1, wherein

when the light is emitted in said step (c), a surface of said semiconductor substrate reaches a temperature of 1000°

C. or more.

3. The semiconductor manufacturing method according to claim 1, wherein

in said step (c), the contact is formed, and impurities implanted into said impurity region are activated.

4. The semiconductor manufacturing method according to claim 3, wherein

in said step (c), recrystallization of said impurity region is promoted.

5. The semiconductor manufacturing method according to claim 1, further comprising the step of

between said steps (a) and (b), emitting light to said semiconductor substrate for one second or less to activate impurities implanted into said impurity region.

6. The semiconductor manufacturing method according to claim 1, wherein

in said step (c), the light emitted to said semiconductor substrate has such spectral distribution that intensity at a wavelength of 300 nm relative to intensity at a wavelength of 500 nm is 20% or more.

7. The semiconductor manufacturing method according to claim 1, further comprising the step of

before said step (c), forming a light absorbing film on said metal layer.

8. The semiconductor manufacturing method according to claim 1, wherein

in said step (a), an n-type impurity region and a p-type impurity region are formed in one side of said semiconductor substrate,

in said step (b), a nickel layer is formed on said n-type impurity region, and an aluminum layer is formed on said p-type impurity region, and

in said step (c), the light is emitted to said one side of said semiconductor substrate to form an n-type contact and a p-type contact simultaneously.

9. The semiconductor manufacturing method according to claim 1, wherein

in said step (c), flash light is emitted from a flash lamp to said semiconductor substrate.

10. The semiconductor manufacturing method according to claim 1, wherein

said semiconductor substrate is formed of silicon carbide.

11. A semiconductor manufacturing apparatus for forming a contact to a semiconductor substrate, the apparatus comprising:

a chamber for housing a semiconductor substrate including an impurity region which is implanted with ions and on which a metal layer has been formed;

a susceptor installed in said chamber to support said semiconductor substrate to be placed thereon;

a forming gas supply unit forming, in said chamber, a forming gas atmosphere containing hydrogen; and

a light emitting unit emitting light to said semiconductor substrate to be supported by said susceptor for one second or less for heating in said forming gas atmosphere.

12. The semiconductor manufacturing apparatus according to claim 11, wherein

said light emitting unit allows a surface of said semiconductor substrate to reach a temperature of 1000°

C. or more by emitting the light.

13. The semiconductor manufacturing apparatus according to claim 11, wherein

said light emitting unit emits the light to said semiconductor substrate to form the contact and to activate impurities implanted into said impurity region.

14. The semiconductor manufacturing apparatus according to claim 13, wherein

said light emitting unit emits the light to said semiconductor substrate to promote recrystallization of said impurity region.

15. The semiconductor manufacturing apparatus according to claim 11, wherein

said light emitting unit emits light to said semiconductor substrate after implantation of the ions and before formation of the metal layer to active impurities implanted into said impurity region.

16. The semiconductor manufacturing apparatus according to claim 11, wherein

the light emitted by said light emitting unit to said semiconductor substrate has such spectral distribution that intensity at a wavelength of 300 nm relative to intensity at a wavelength of 500 nm is 20% or more.

17. The semiconductor manufacturing apparatus according to claim 11, wherein

a light absorbing film has been formed on said metal layer formed on said semiconductor substrate to which the light is emitted by said light emitting unit.

18. The semiconductor manufacturing apparatus according to claim 11, wherein

an n-type impurity region and a p-type impurity region have been formed in one side of said semiconductor substrate, and a nickel layer and an aluminum layer have respectively been formed on said n-type impurity region and said p-type impurity region, and

said light emitting unit emits the light to said one side of said semiconductor substrate to form an n-type contact and a p-type contact simultaneously.

19. The semiconductor manufacturing apparatus according to claim 11, wherein

said light emitting unit includes a flash lamp emitting flash light.

20. The semiconductor manufacturing apparatus according to claim 11, wherein

said semiconductor substrate is formed of silicon carbide.