Patent ID: 8821752

Claim:
An etching composition comprising a silyl phosphate compound represented by the following formula 1, phosphoric acid and deionized water: wherein R 1 is selected from the group consisting of hydrogen, hydroxyl, substituted or unsubstituted (C 1 -C 20 )alkyl, (C 1 -C 20 )alkoxy, (C 2 -C 20 )alkenyl, (C 3 -C 20 )cycloalkyl, amino(C 1 -C 20 )alkyl, amino(C 1 -C 10 )alkylamino(C 1 -C 10 )alkyl, (C 6 -C 20 )aryl, (C 1 -C 20 )alkylcarbonyl, (C 1 -C 20 )alkylcarbonyloxy and cyano(C 1 -C 10 )alkyl; wherein R 2 and R 3 are each independently selected from the group consisting of hydrogen, hydroxyl, substituted or unsubstituted (C 1 -C 20 )alkyl, (C 1 -C 20 )alkoxy, (C 2 -C 20 )alkenyl, (C 3 -C 20 )cycloalkyl, amino(C 1 -C 20 )alkyl, amino(C 1 -C 10 ) alkylamino(C 1 -C 10 )alkyl, (C 6 -C 20 )aryl, (C 1 -C 20 )alkylcarbonyl, (C 1 -C 20 )alkylcarbonyloxy, cyano(C 1 -C 10 )alkyl, and a group represented by the following formula 3: wherein R 4 and R 5 are each independently selected from the group consisting of hydrogen, (C 1 -C 10 )alkyl, (C 2 -C 10 )alkenyl, (C 3 -C 20 )cycloalkyl, amino(C 1 -C 10 )alkyl, and (C 1 -C 10 )alkyl substituted with one or more substituents selected from the group consisting of halogen, phenyl and cyclohexene oxide; and wherein n is an integer of 1≦n≦4.