Semiconductor device and method of manufacturing the same

Abstract

Hexachlorodisilane (Si 2 Cl 6 ) is used as a Si raw material for forming a silicon nitride film that can be widely different in the etching rate from a silicon oxide film. The silicon nitride film is formed by an LPCVD method.

What is claimed is: 
     
       1. A method of manufacturing a semiconductor device, comprising the steps of:
 preparing a semiconductor substrate; and 
 forming a silicon nitride insulation film on said semiconductor substrate by a low pressure chemical vapor deposition method using a compound having a Si—Si bond and a Si—Cl bond as a Si raw material, wherein 
 said silicon nitride film is formed to cover the surfaces of said semiconductor substrate and a gate electrode formed on the semiconductor substrate, and said method further comprises the steps of: 
 forming an interlayer insulating film on said silicon nitride film; and 
 forming a through-hole extending through a portion of said interlayer insulating film and silicon nitride film to reach the surface of the semiconductor substrate. 
 
     
     
       2. A method of manufacturing a semiconductor device according to  claim 1 , wherein said silicon nitride film is formed to cover the surfaces of said semiconductor substrate and a gate electrode formed on the semiconductor substrate, and said method further comprises the steps of:
 forming an interlayer insulating film on said silicon nitride film; and   forming a through-hole extending through a portion of said interlayer insulating film and silicon nitride film to reach the surface of the semiconductor substrate.   
     
     
       3. A method of manufacturing a semiconductor device according to claim  2  1, wherein the raw material of said silicon nitride film is represented by a general formula Si n Cl 2+2−x H x , where n is an integer not smaller than 2, and x is an integer not larger than 2n+1. 
     
     
       4. A method of manufacturing a semiconductor device according to  claim 1 , wherein the said silicon nitride film is formed to a thickness of 10 nm or more. 
     
     
       5. A method of manufacturing a semiconductor device according to claim 1, wherein a film containing chlorine is formed on a side wall of a gate electrode formed on the semiconductor substrate. 
     
     
       6. A method of manufacturing a semiconductor device according to claim 5, wherein the film containing chlorine has an excess amount of silicon as compared to a stoichiometric ratio of a Si 3 N 4  film. 
     
     
       7. A method of manufacturing a semiconductor device according to claim 5, wherein the film formed on the side wall of the gate includes chlorine in a concentration of at least 4×10 20  cm −3 . 
     
     
       8. A method of manufacturing a semiconductor device according to claim 5, wherein the gate electrode has a laminate structure including a metal gate layer. 
     
     
       9. A method of manufacturing a semiconductor device according to claim 5, wherein the gate electrode is metal. 
     
     
       10. A method of manufacturing a semiconductor device according to claim 5, wherein the silicon nitride film is formed to a thickness of 10 nm or more. 
     
     
       11. A method of manufacturing a semiconductor device according to claim 5, wherein a gate insulating film is formed between the semiconductor substrate and the gate electrode, and the gate insulating film is a high dielectric constant material. 
     
     
       12. A method of manufacturing a semiconductor device according to claim 11, wherein the gate electrode comprises Ti. 
     
     
       13. A method of manufacturing a semiconductor device according to claim 5, wherein the silicon nitride insulation film has a density not higher than 2.4 g/cm 3 . 
     
     
       14. A method of manufacturing a semiconductor device according to claim 5, wherein the silicon nitride insulation film is formed at a temperature of 700° C. or less. 
     
     
       15. A method of manufacturing a semiconductor device according to claim 5, wherein NH 3  is used as a nitrogen source for forming the silicon nitride insulation film. 
     
     
       16. A method of manufacturing a semiconductor device according to claim 1, wherein the silicon nitride insulation film has an excess amount of silicon as compared to a stoichiometric ratio of a Si 3 N 4  film. 
     
     
       17. A method of manufacturing a semiconductor device according to claim 1, wherein the silicon nitride film includes chlorine in a concentration of at least 4×10 20  cm −3 . 
     
     
       18. A method of manufacturing a semiconductor device according to claim 1, wherein the gate electrode has a laminate structure including a metal gate layer. 
     
     
       19. A method of manufacturing a semiconductor device according to claim 1, wherein the gate electrode is metal. 
     
     
       20. A method of manufacturing a semiconductor device according to claim 1, wherein a gate insulating film is formed between the semiconductor substrate and the gate electrode, and the gate insulating film is a high dielectric constant material. 
     
     
       21. A method of manufacturing a semiconductor device according to claim 17, wherein the gate electrode comprises Ti. 
     
     
       22. A method of manufacturing a semiconductor device according to claim 1, wherein the silicon nitride insulation film has a density not higher than 2.4 g/cm 3 . 
     
     
       23. A method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor substrate includes a copper wiring and the silicon nitride insulation film is formed on a surface of the copper wiring.