POLISHING PAD WITH ADJUSTED CONTENT OF CHLORINE AND PROCESS FOR PREPARING SEMICONDUCTOR DEVICE USING THE SAME

1 . A polishing pad, which comprises a polishing layer and a support layer, wherein the polishing layer comprises a urethane-based prepolymer, a foaming agent, and a curing agent, and the polishing layer has a content of chlorine (Cl) of 10,000 ppm or less when analyzed according to the IEC 62321-3-2 standard.

2 . The polishing pad of claim 1 , wherein the polishing layer has a content of chlorine (Cl) of 10 ppm to 1,000 ppm when analyzed according to the IEC 62321-3-2 standard.

3 . The polishing pad of claim 1 , wherein the foaming agent comprises a solid phase foaming agent, and the solid phase foaming agent comprises at least one selected from the group consisting of an acrylonitrile-based copolymer, a methyl methacrylate-based copolymer, a methacrylonitrile-based copolymer, and an acrylic-based copolymer.

4 . The polishing pad of claim 1 , wherein the curing agent comprises at least one selected from the group consisting of diethyltoluenediamine (DETDA), 3,5-dimethylthio-2,6-diaminotoluene (DMTDA), 1,3-propanediol bis(4-aminobenzoate) (PDPAB), N,N′-bis(sec-butylamino)diphenylmethane, 2,6-bis(methylthio)-4-methyl-1,3-benzenediamine, 4-(4-aminobenzoyl)oxyphenyl 4-aminobenzoate, 4-(4-aminobenzoyl)oxybutyl 4-aminobenzoate, 4-[4-(4-aminobenzoyl)oxy-3-methylbutoxy]butyl 4-aminobenzoate, and methylene bis-methylanthranilate (MBNA).

5 . The polishing pad of claim 1 , wherein the polishing layer has a hardness of 50 Shore D to 65 Shore D, a tensile strength of 15 N/mm 2 to 25 N/mm 2 , and an elongation of 90% to 130%.

6 . The polishing pad of claim 1 , wherein the zeta potential value of an aqueous solution of a pH of 5.5 containing debris obtained by conditioning the polishing layer at a concentration of 0.01% by weight is-10 mV to 30 mV.

7 . The polishing pad of claim 1 , wherein, when the polishing pad is conditioned while deionized water is supplied at 300 cc/minute under the conditions of a platen speed of 93 rpm, a conditioner load of 9 lbs., a conditioner speed of 64 rpm, and a sweep of 19 times/minute, the D50 particle size of the polishing pad debris formed is 30 μm or less.

8 . The polishing pad of claim 1 , wherein, when the silicon oxide layer of a silicon wafer is polished with a ceria slurry using the polishing pad, the polishing rate according to the following Equation 1 is 2,200 Å/minute to 2,600 Å/minute:

Polishing rate (Å/minute)=polished thickness of a silicon wafer (Å)/polishing time (minute).  [Equation 1]

9 . A process for preparing a polishing pad, which comprises:

preparing a composition for a polishing pad comprising a urethane-based prepolymer, a foaming agent, and a curing agent;

injecting the composition for a polishing pad into a mold and curing it to prepare a polishing layer; and

laminating the polishing layer with a support layer,

wherein the foaming agent comprises a solid phase foaming agent, the solid phase foaming agent comprises at least one selected from the group consisting of an acrylonitrile-based copolymer, a methyl methacrylate-based copolymer, a methacrylonitrile-based copolymer, and an acrylic-based copolymer, and

the curing agent comprises at least one selected from the group consisting of diethyltoluenediamine (DETDA), 3,5-dimethylthio-2,6-diaminotoluene (DMTDA), 1,3-propanediol bis(4-aminobenzoate) (PDPAB), N,N′-bis(sec-butylamino)diphenylmethane, 2,6-bis(methylthio)-4-methyl-1,3-benzenediamine, 4-(4-aminobenzoyl)oxyphenyl 4-aminobenzoate, 4-(4-aminobenzoyl)oxybutyl 4-aminobenzoate, 4-[4-(4-aminobenzoyl)oxy-3-methylbutoxy]butyl 4-aminobenzoate, and methylene bis-methylanthranilate (MBNA).

10 . A process for preparing a semiconductor device, which comprises polishing the surface of a semiconductor substrate using the polishing pad of claim 1 .