MOCVD of indium oxide and indium/tin oxide films on substrates

• US 5,147,688 A
• Filed: 01/11/1991
• Issued: 09/15/1992
• Est. Priority Date: 04/24/1990
• Status: Expired due to Fees

• Current Assignee: CVD, Inc. (Dow, Inc.)
• Original Assignee: CVD, Inc. (Dow, Inc.)
• Inventors: Melas, Andreas A.
• Primary Examiner(s): Lusignan, Michael
• Assistant Examiner(s): King, Roy V.
• Application Number:
  US07/639,374
• Time in Patent Office: 613 Days
• Field of Search: 427/255.3, 427/255.2, 427/255.1, 427/248.1, 427/109, 427/126.3, 427/314, 427/166, 427/165, 428/432, 65/60.52
• US Class Current: 427/255.32
• CPC Class Codes: C23C 16/407 of zinc, germanium, cadmium, indium, tin, thallium or bismuth

Abstract

Disclosed is a metalorganic chemical vapor deposition (MOCVD) process of depositing an indium oxide or an indium/tin oxide film on a substrate using indium alkyl etherate or indium alkyl etherate and organotin compound precursors, respectively.

Claims

1. The process of depositing an oxide coating containing indium on a substrate comprising:

(A) transporting, in an inert carrier gas, vapors of an indium alkyl etherate having a melting point of less than 100 degrees Celsius and a vapor pressure of at least 1 torr at a temperature in the range of from minus 20 degrees to 100 degrees Celsius and which is a liquid at room temperature and ambient atmospheric pressure;

(B) heating said substrate to a temperature of from about 200 to 800 degrees Celsius; and

(C) contacting said heated substrate in an oxidizing atmosphere with vapors from said indium alkyl etherate to form said oxide coating containing indium on said substrate.

2. The process of claim 1 wherein said indium alkyl etherate has a melting point of less than 30 degrees Celsius.

3. The process of claim 1 wherein said oxidizing atmosphere comprises oxygen gas.

4. The process of claim 1 wherein said oxidizing atmosphere comprises a mixture of oxygen gas and water vapor.

5. The process of claim 1 wherein said inert carrier gas comprises nitrogen.

6. The process of claim 1 wherein said indium alkyl etherate is trimethylindium etherate.

7. The process of depositing an oxide coating containing indium and tin on a substrate comprising:

(A) transporting, in an inert carrier gas, vapors of an indium alkyl etherate having a melting point of less that 100 degrees Celsius and a vapor pressure of at least 1 torr at a temperature in the range of from minus 200 degrees to 100 degrees Celsius and which is a liquid at room temperature and ambient atmospheric pressure;

(B) transporting in an inert carrier gas vapors of an organotin compound having at least one oxygen atom in a molecule thereof, having a melting point of less that 100 degrees Celsius and a vapor pressure of at least 1 torr at a temperature in the range of from minus 20 degrees to 100 degrees Celsius, and having a thermal stability such that the mole percent decomposition of said organotin compound at a given temperature is in a range of from 10 percent to 100 percent of the mole percent decomposition of said indium alkyl etherate at said given temperature;

(C) heating said substrate to a temperature of from about 200 to 800 degrees Celsius; and

(D) contacting said heated substrate in an oxidizing atmosphere with vapors from said indium alkyl etherate and said organotin compound to form said oxide coating containing indium and tin on said substrate.

8. The process of claim 7 wherein said indium alkyl etherate has a melting point of less than 30 degrees Celsius.

9. The process of claim 7 wherein said oxidizing atmosphere comprises oxygen gas.

10. The process of claim 7 wherein said oxidizing atmosphere comprises a mixture of oxygen gas and water vapor.

11. The process of claim 7 wherein the amounts of said vapors of said indium compound and said vapors of said organotin compound are selected so as to provide a percent by weight ratio of indium to tin respectively in vapor phase of from about 75:

25 to about 85;

15.

12. The process of claim 7 wherein the amounts of said vapors of said indium alkyl etherate and said vapors of said organotin compound are selected so as to provide a percent by weight ratio of indium to tin respectively in vapor phase of from about 80:

20.

13. The process of claim 7 wherein said inert carrier gas, for said vapors of said indium compound and for said vapors of said organotin compound, comprises nitrogen.

14. The process of claim 7 wherein said indium alkyl etherate is trimethylindium etherate.