Method for manufacturing a semiconductor integrated circuit device that includes covering the bottom of an isolation trench with spin-on glass and etching back the spin-on glass to a predetermined depth
View Patent ↗A method for manufacturing a semiconductor integrated circuit device includes the steps of forming an isolation trench in an isolation region of a semiconductor substrate, filling the isolation trench up to predetermined middle position in its depth direction with a first insulating film deposited by a coating method, filling a remaining depth portion of the isolation trench into which the first insulating film is filled with a second insulating film, then forming a plurality of patterns on the semiconductor substrate, filling a trench forming between the plurality of patterns up to predetermined middle position in a trench depth direction with a third insulating film deposited by a coating method, and filling a remaining portion of the trench into which the third insulating film is filled with a fourth insulating film that is more difficult to etch than the third insulating film. The method may also include the step of forming dummy patterns in a relatively large isolation region of isolation regions with relatively different planar dimensions before the first insulating film is deposited
1. A method for manufacturing a semiconductor integrated circuit device, comprising the steps of:
(a) forming an isolation trench in an isolation region of a semiconductor substrate;
(b) forming a spin-on-glass film in said isolation trench by a coating method so as to cover a bottom of said isolation trench;
(c) etching said spin-on-glass film up to a predetermined position in a depth direction of said isolation trench;
(d) performing thermal processing on said semiconductor substrate; and
(e) filling a remaining depth portion of said isolation trench with an insulating film,
wherein an etching rate of said insulating film is lower than that of said spin-on-glass film.
2. A method for manufacturing a semiconductor integrated circuit device according to claim 1 , wherein said insulating film is filled into said remaining depth portion of said isolation trench by a chemical vapor deposition method.
3. A method for manufacturing a semiconductor integrated circuit device according to claim 1 , wherein said step (e) comprises the step of depositing said insulating film on a main surface of said semiconductor substrate, and further comprising the step of polishing said insulating film on the main surface of said semiconductor substrate by a chemical mechanical polishing method after said depositing step.
4. A method for manufacturing a semiconductor integrated circuit device according to claim 1 , wherein said etching rate is a wet-etching rate.
5. A method for manufacturing a semiconductor integrated circuit device according to claim 1 , wherein said step (b) comprises the step of depositing said spin-on-glass film on a main surface of said semiconductor substrate by a rotary coating method such that the deposited spin-on-glass film has a planarized surface.
6. A method for manufacturing a semiconductor integrated circuit device according to claim 1 , wherein said spin-on-glass film has liquidity with a 100 mPa·s or lower viscosity coefficient at a temperature of 25° C.
7. A method for manufacturing a semiconductor integrated circuit device, comprising the steps of:
(a) forming an isolation trench in an isolation region of a semiconductor substrate;
(b) filling said isolation trench with a spin-on-glass film coated by a coating method;
(c) etching said spin-on-glass film up to a predetermined position in a depth direction of said isolation trench;
(d) performing thermal processing on said semiconductor substrate after said step (c);
(e) depositing an insulating film on a main surface of said semiconductor substrate by a chemical vapor deposition method so as to fill a remaining depth portion of said isolation trench; and
(f) polishing said insulating film on said main surface of said semiconductor substrate by a chemical mechanical polishing method,
wherein said insulating film is more difficult to be etched than said spin-on-glass film.
8. A method for manufacturing a semiconductor integrated circuit device according to claim 7 , wherein said spin-on-glass film includes polysilazane.
9. A method for manufacturing a semiconductor integrated circuit device according to claim 7 , wherein said spin-on-glass film is an inorganic spin-on-glass film.
10. A method for manufacturing a semiconductor integrated circuit device according to claim 7 , wherein said step (b) comprises the step of coating said spin-on-glass film on a main surface of said semiconductor substrate by a rotary coating method such that the coated spin-on-glass film has a planarized surface.
11. A method for manufacturing a semiconductor integrated circuit device according to claim 7 , wherein said spin-on-glass film has liquidity with a 100 mPa·s or lower viscosity coefficient at a temperature of 25° C.
12. A method for manufacturing a semiconductor integrated circuit device, comprising the steps of:
(a) forming an isolation trench in an isolation region of a semiconductor substrate;
(b) filling said isolation trench with a spin-on-glass film coated by a coating method;
(c) etching said spin-on-glass film up to a predetermined position in a depth direction of said isolation trench;
(d) performing thermal processing on said semiconductor substrate after said step (c), wherein said step (d) is a step for improving a film quality of said spin-on-glass film;
(e) depositing an insulating film on a main surface of said semiconductor substrate by a chemical vapor deposition method so as to fill a remaining depth portion of said isolation trench; and
(f) polishing said insulating film on said main surface of said semiconductor substrate by a chemical mechanical polishing method.
13. A method for manufacturing a semiconductor integrated circuit device, comprising the steps of:
(a) forming an isolation trench in an isolation region of a semiconductor substrate;
(b) filling said isolation trench with a spin-on-glass film coated by a coating method;
(c) etching said spin-on-glass film up to a predetermined position in a depth direction of said isolation trench;
(d) performing thermal processing on said semiconductor substrate after said step (c), wherein said step (d) is a step for reducing a wet-etching rate of said spin-on-glass film;
(e) depositing an insulating film on a main surface of said semiconductor substrate by a chemical vapor deposition method so as to fill a remaining depth portion of said isolation trench; and
(f) polishing said insulating film on said main surface of said semiconductor substrate by a chemical mechanical polishing method.