Semiconductor substrate semiconductor device and liquid crystal display device

• US 6,057,557 A
• Filed: 07/08/1999
• Issued: 05/02/2000
• Est. Priority Date: 12/07/1992
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ichikawa, Takeshi
• Primary Examiner(s): Abraham, Fetsum
• Application Number:
  US09/349,076
• Time in Patent Office: 299 Days
• Field of Search: 257/49-51, 257/59, 257/66, 257/62, 257/72
• US Class Current: 257/59
• CPC Class Codes: C30B 23/002 Controlling or regulating
• CPC Class Codes: C30B 23/066 Heating of the material to be evaporated
• CPC Class Codes: C30B 29/06 Silicon
• CPC Class Codes: H01L 21/02043 Cleaning before device manufacture, i.e. Begin-Of-Line process
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 21/02661 In-situ cleaning

Abstract

A method of forming an Si film by a bias sputtering process comprises the steps of generating plasma between a target electrode holding a target material provided in a vacuum container and a substrate electrode holding a deposited film forming substrate, provided opposingly to the target electrode, by the use of a high-frequency energy to cause the target material to undergo sputtering, and applying a bias voltage to at least one of the target electrode and the substrate electrode to form an Si film comprised of atoms deposited by sputtering on the substrate, wherein;

a mixed-gas environment comprising a mixture of an inert gas and a hydrogen gas is formed in the vacuum container, and the target material is subjected to sputtering while controlling H₂ O gas, CO gas and CO₂ gas in the mixed-gas environment to have a partial pressure of 1.0×10^-8 Torr or less each, to form an epitaxial film on the substrate while maintaining a substrate temperature in the range of from 400° C. to 700° C.

A semiconductor substrate comprises an Si layer having a carbon content, a hydrogen content and a rare gas (X) content of C≦1×10¹⁸ cm^-3, 1×10¹⁵ cm^-3 ≦H≦1×10²⁰ cm^-3 and 1×10¹⁶ cm^-3 ≦X, respectively, and having a difference of 15 nm or less between a maximum value and a minimum value of surface roughness.

Claims

1. A semiconductor substrate comprising an Si layer having a carbon content, a hydrogen content and a rare gas (X) content of C≦

1×

10¹⁸ cm^-3, 1×

10¹⁵ cm^-3 ≦

H≦

1×

10²⁰ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X, respectively, and having a difference of 15 nm or less between a maximum value and a minimum value of surface roughness.

2. The semiconductor substrate according to claim 1, wherein said Si layer is monocrystalline, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁶ cm^-3 ≦

H≦

1×

10¹⁹ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X≦

1×

10¹⁸ cm^-3.

3. The semiconductor substrate according to claim 1, wherein said Si layer is polycrystalline, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁷ cm^-3 ≦

H≦

1×

10¹⁹ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X≦

1×

10¹⁹ cm^-3.

4. The semiconductor substrate according to claim 1, wherein said Si layer is amorphous, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁷ cm^-3 ≦

H≦

1×

10²⁰ cm^-3 and 1×

10¹⁷ cm^-3 ≦

X≦

1×

10²⁰ cm^-3.

5. The semiconductor device according to claim 1, wherein said Si layer is amorphous, and C≦

5×

10 cm³, 1×

10¹⁷ cm^-3 ≦

H≦

1×

10²⁰ cm^-3 and 1×

10¹⁷ cm³ ≦

X≦

1×

10²⁰ cm^-3.

6. A semiconductor device comprising an Si semiconductor layer having a carbon content, a hydrogen content and a rare gas (X) content of C≦

1×

10¹⁸ cm^-3, 1×

10¹⁵ cm^-3 ≦

H≦

1×

10²⁰ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X, respectively, and having a difference of 15 nm or less between a maximum value and a minimum value of surface roughness.

7. The semiconductor device according to claim 6, wherein said Si layer is monocrystalline, an c≦

5 ×

10¹⁷ cm^-3, 1×

10¹⁶ cm^-3 ≦

H≦

1×

10¹⁹ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X≦

1×

10¹⁸ cm^-3.

8. The semiconductor device according to claim 6, wherein said Si layer is polycrystalline, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁷ cm^-3 ≦

H≦

1×

10¹⁹ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X≦

1×

10¹⁹ cm^-3.

9. An active matrix type liquid-crystal display device comprising a picture element whose switching transistor comprises an Si layer having a carbon content, a hydrogen content and a rare gas (X) content of C≦

1×

10¹⁸ cm^-3, 1×

10¹⁵ cm^-3 ≦

H≦

1×

10²⁰ cm^-3 and 1×

10¹⁶ cm^-3 cm^-3 ≦

X, respectively, and having a difference of 15 nm or less between a maximum value and a minimum value of surface roughness.

10. The liquid-crystal display device according to claim 9, wherein said Si layer is monocrystalline, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁶ cm^-3 ≦

H≦

1×

10¹⁹ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X≦

1×

10¹⁸ cm^-3.

11. The liquid-crystal display device according to claim 9, wherein said Si layer is polycrystalline, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁷ cm^-3 ≦

H≦

1×

10¹⁹ cm^-3 and 1×

10¹⁶ cm^-3 ≦

X≦

1×

10¹⁹ cm^-3.

12. The liquid-crystal display device according to claim 9, wherein said Si layer is amorphous, and C≦

5×

10¹⁷ cm^-3, 1×

10¹⁷ cm^-3 ≦

H≦

1×

10²⁰ cm^-3 and 1 x 10¹⁷ cm^-3 ≦

X≦

1×

10²⁰ cm^-3.