Semiconductor device manufacturing method and semiconductor manufacturing apparatus

1. A semiconductor device manufacturing method, comprising:

forming, by a thermal chemical vapor deposition method, a silicon nitride film on an object to be film-formed disposed in a reaction container, with bis tertiary butyl amino silane and NH 3 flowing into said reaction container, and

removing silicon nitride formed in said reaction container, with cleaning gas flowing into said reaction container, before said silicon nitride formed in said reaction container reaches a thickness of 4,000 Å.

2. A semiconductor device manufacturing method as recited in claim 1 , wherein

said removing said silicon nitride is carried out when said silicon nitride formed in said reaction container reaches a thickness of equal to or more than 3,000 Å and less than 4,000 Å.

3. A semiconductor device manufacturing method as recited in claim 1 , wherein

said removing said silicon nitride is carried out after said silicon nitride formed in said reaction container reaches a thickness of 3,000 Å.

4. A semiconductor device manufacturing method as recited in claim 1 , wherein

said removing said silicon nitride is carried out when said silicon nitride formed in said reaction container reaches a thickness of equal to or less than 3,000 Å.

5. A semiconductor device manufacturing method, comprising:

forming a silicon nitride film on an object to be film-formed disposed in a reaction container made of quartz, with bis tertiary butyl amino silane and NH 3 flowing into said reaction container; and

removing silicon nitride formed in said reaction container, with cleaning gas flowing into said reaction container, before said silicon nitride formed in said reaction container reaches a thickness of 4,000 Å and a microcrack is generated in the quartz.

6. A semiconductor device manufacturing method comprising:

inserting a boat made of quartz and holding an object to be film-formed into a reaction container made of quartz;

forming a silicon nitride film on the object held by said boat in said reaction container, with bis tertiary butyl amino silane and NH 3 as raw gases flowing into said reaction container;

carrying said boat holding the object after said silicon nitride film-forming out of said reaction container;

inserting said boat not holding the object into said reaction container;

removing silicon nitride formed in said reaction container and on said boat, with cleaning gas flowing into said reaction container in which said boat not holding the object is inserted, before said silicon nitride formed in said reaction container or on said boat reaches a thickness of 4,000 Å and a microcrack is generated in the quartz; and

carrying said boat not holding the object out of said reaction container.

7. A semiconductor device manufacturing method, comprising:

forming a silicon nitride film on an object to be film-formed disposed in a reaction container, with bis tertiary butyl amino silane and NH 3 flowing into said reaction container; and

removing silicon nitride formed in said reaction container, with cleaning gas flowing into said reaction container, when said silicon nitride formed in said reaction container reaches a thickness of 3,000 Å.

8. A semiconductor device manufacturing method comprising:

inserting a boat holding an object to be film-formed into a reaction container;

forming a silicon nitride film on the object held by said boat in said reaction container, with bis tertiary butyl amino silane and NH 3 as raw gases flowing into said reaction container;

carrying said boat holding the object after said silicon nitride film-forming out of said reaction container;

inserting said boat not holding the object into said reaction container;

removing silicon nitride formed in said reaction container and on said boat, with cleaning gas flowing into said reaction container in which said boat not holding the object is inserted, when said silicon nitride formed in said reaction container or on said boat reaches a thickness of 3,000 Å; and

carrying said boat not holding the object out of said reaction container.

9. A semiconductor device manufacturing method, comprising:

forming, by a thermal chemical vapor deposition method, a silicon nitride film on an object to be film-formed disposed in a reaction container made of quartz, with bis tertiary butyl amino silane and NH 3 flowing into said reaction container; and

thereafter removing silicon nitride formed in said reaction container, with NF 3 gas flowing into said reaction container in a state where a pressure in said reaction container is kept 10 Torr to 70 Torr, before said silicon nitride formed in said reaction container reaches a thickness of 4,000 Å.

10. A semiconductor device manufacturing method, comprising:

forming, by a thermal chemical vapor deposition method, a silicon nitride film on an object to be film-formed disposed in a reaction container made of quartz, with bis tertiary butyl amino silane and NH 3 flowing into said reaction container; and

thereafter removing silicon nitride formed in said reaction container, with NF 3 gas flowing into said reaction container in a state where a pressure in said reaction container is kept 10 Torr to 70 Torr, when said silicon nitride formed in said reaction container reaches a thickness of 3,000 Å.