Polishing compound for semiconductor integrated circuit device, polishing method and method for producing semiconductor integrated circuit device
View Patent ↗To provide a technique employed when a plane to be polished of a silicon dioxide type material layer is polished in production of a semiconductor integrated circuit device, which is capable of polishing protruded portions by priority while suppressing polishing at recessed portions and planarizing the plane to be polished at a high level with an extremely small polishing amount, with small pattern dependence of the polishing rate. In production of a semiconductor integrated circuit device, when a plane to be polished is a plane to be polished of a silicon dioxide type material layer, a polishing compound containing cerium oxide particles, a water-soluble polyamine and water is used as a polishing compound for chemical mechanical polishing to polish the plane to be polished.
1. A polishing composition for chemical mechanical polishing a plane of a silicon dioxide type material layer to be polished in production of a semiconductor integrated circuit device, wherein the polishing composition has a pH of from 9 to 12 and comprises:
cerium oxide particles having an average particle size from 0.01 to 0.5 μm;
a water-soluble polyamine having a weight average molecular weight from 100 to 100,000 selected from the group consisting of water-soluble polyether polyamine, water-soluble polyalkylene polyamine, water-soluble polyethyleneimine, water-soluble polyvinylamine, water-soluble polyallylamine, water-soluble polylysine and water-soluble chitosan; and
water.
2. The polishing composition according to claim 1 , wherein the silicon dioxide type material layer is a borophosphosilicate glass (BPSG) layer, a borosilicate glass (BSG) layer or a phosphosilicate glass (PSG) layer.
3. The polishing composition according to claim 1 , wherein the concentration of phosphorus, boron, or phosphorus and boron, in the silicon dioxide type material layer, is from 0.1 to 20 mass %.
4. The polishing composition according to claim 1 , wherein the silicon dioxide type material layer is a silicon dioxide layer.
5. The polishing composition according to claim 1 , wherein the water-soluble polyamine is at least one water-soluble polyamine selected from the group consisting of a water-soluble polyether polyamine and a water-soluble polyalkylene polyamine.
6. The polishing composition according to claim 1 , wherein the water-soluble polyamine has a weight average molecular weight of from 100 to 2,000.
7. The polishing composition according to claim 1 , wherein the water-soluble polyamine has a weight average molecular weight of from 150 to 800.
8. The polishing composition according to claim 1 , which contains the water-soluble polyamine in an amount of from 0.001 to 20 mass % based on the total mass of the polishing composition.
9. The polishing composition according to claim 1 , which contains the water-soluble polyamine in an amount of from 0.05 to 5 mass % based on the total mass of the polishing composition.
10. The polishing composition according to claim 1 , wherein the water-soluble polyamine has a weight average molecular weight of from 150 to 400.
11. A method for polishing a plane to be polished, which comprises supplying a polishing compound to a polishing pad, and bringing a plane to be polished of a semiconductor integrated circuit device and the polishing pad into contact with each other to polish the plane to be polished by relative movement between them, wherein the plane to be polished is a plane to be polished of a silicon dioxide type material layer, and the polishing compound as defined in claim 1 is used as the polishing compound.
12. A method for producing a semiconductor integrated circuit device, which comprises a step of polishing a plane to be polished by the polishing method as defined in claim 11 .
13. The polishing composition according to claim 1 , wherein the cerium oxide particles have an average particle size of 0.02 to 0.3 μm.
14. The polishing composition according to claim 1 , wherein the cerium oxide particles have an average particle size of 0.05 to 0.2 μm.
15. The polishing composition according to claim 1 , wherein the silicon dioxide type material layer is a phosphosilicate glass (PSG) layer.
16. The polishing composition according to claim 1 , wherein the silicon dioxide material layer is a borophosphosilicate glass (BPSG) layer.
17. The polishing composition according to claim 1 , wherein the water-soluble polyamine is a water-soluble polyether diamine or water-soluble polyalkylene polyamine represented by the following general formula (1):
H 2 N—(R—X) k —R—NH 2 (1)
wherein each R is independently a C 2 -C 8 alkylene group, X is an oxygen atom or an —NH— group, and k is either an integer of at least 2 when X is an oxygen atom or an integer of at least 1 when X is an —NH— group.
18. The polishing composition according to claim 1 , wherein the water-soluble polyamine is a water-soluble polyether diamine represented by the following general formula (2):
H 2 N—R 2 —O—(R 1 —O) m —R 2 —NH 2 (2)
wherein each R 1 is independently an ethylene group or a propylene group, each R 2 is independently a C 2 -C 6 alkylene group, and m is an integer of at least 2.
19. The polishing composition according to claim 18 , wherein the water-soluble polyether diamine according to general formula (2) is selected from the group consisting of polyoxyethylene diamine, polyoxypropylene diamine and 4,7,10-trioxamidecane-1,13-diamine.
20. The polishing composition according to claim 1 , wherein the water-soluble polyamine is a water-soluble polyalkylene polyamine represented by the following general formula (3):
H 2 N—R 4 —NH—(R 3 —NH) n —R 4 —NH 2 (3)
wherein each R 3 is independently a C 2 -C 6 alkylene group, each R 4 is independently a C 2 -C 8 alkylene group, and n is an integer of at least 1.
21. The polishing composition according to claim 20 , wherein the water-soluble polyalkylene polyamine according to general formula (3) is selected from the group consisting of tetraethylenepentamine, pentaethylenehexamine, heptaethyleneoctamine, N,N′-bis(3-aminopropyl)-ethylenediamine and N,N′-bis(2-aminoethyl)-1,4-butanediamine.