Patent ID: 7056829

Claim:
A polishing method for removing at least one coating layer from a semiconductor substrate, the semiconductor substrate including silicon nitride, silicon carbide nitride and a dielectric comprising the step of polishing with an aqueous composition, the aqueous composition comprising a nonionic surfactant that suppresses removal rate of silicon carbide-nitride, the nonionic surfactant having a hydrophilic group and a hydrophobic group, the hydrophobic group having a carbon chain length of greater than three, the nonionic surfactant being selected from the group comprising alkanoamide, alkyl polyethylene oxide, alkylphenol polyethylene oxide and a mixture thereof for removing silicon nitride and stopping on a silicon carbide-nitride layer and the nonionic surfactant suppresses silicon carbide-nitride removal rate at least 100 angstroms per minute greater than its decrease in silicon nitride removal rate as measured with a microporous polyurethane polishing pad pressure measured normal to a wafer of 13.8 kPa.