Method and apparatus for the production of SiC by means of CVD with improved gas utilization

• US 6,299,683 B1
• Filed: 01/30/1997
• Issued: 10/09/2001
• Est. Priority Date: 01/30/1996
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Voelkl, Johannes, Rupp, Roland
• Primary Examiner(s): BUEKER, RICHARD R
• Application Number:
  US08/791,519
• Time in Patent Office: 1,713 Days
• Field of Search: 118/715, 118/719, 118/725, 117/88, 117/98, 117/951, 427/249, 427/249.15
• US Class Current: 117/88
• CPC Class Codes: C23C 16/325 Silicon carbide
• CPC Class Codes: C23C 16/455 characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber
• CPC Class Codes: C23C 16/45519 Inert gas curtains

Abstract

A process gas stream (2) is generated, from which SiC is deposited on a substrate (4) by means of CVD. Furthermore, a second gas stream (3) of an inert gas is generated, which substantially surrounds the process gas stream (2) in its direction of flow. This results in a higher yield of the process gases.

Claims

1. A method for producing silicon carbide, comprising the steps of:

directing a first gas stream (2) at a substrate (4), the first gas stream (2) containing at least one working gas (SiZ, CY) for providing silicon (Si) and carbon (C) and at least one carrier gas, whereby silicon carbide is deposited on the substrate (4) by chemical vapor deposition (CVD) from the first gas stream (2),

generating a second gas stream (3) parallel to the direction of flow of and substantially surrounding the first gas stream (2), and

adjusting a flow velocity of the first gas stream (2) to be between approximately 10 m/min and approximately 300 m/min.

2. The method according to claim 1, wherein the flow velocity of the first gas stream (2) is between approximately 20 m/min and approximately 60 m/min.

3. The method according to claim 1, further comprising:

adjusting the flow velocity of the first gas stream (2) to be greater than the flow velocity of the second gas stream (3).

4. The method according to claim 1, wherein a viscosity of the second gas stream (3) is lower than a viscosity of the first gas stream (2).

5. The method according to claim 1, wherein the second gas stream (3) comprises at least one inert gas.

6. The method according to claim 1, further comprising:

adjusting a growth temperature on the substrate (4) to be between approximately 800°

C. and approximately 2500°

C.

7. The method according to claim 1 wherein monocrystalline silicon carbide is produced.