an improved slurry for polish removal . one application of this slurry is for shallow trench isolation processing in semiconductor manufacturing . the improved slurry has an enhanced oxide to nitride polish removal selectivity . a modified slurry is formed by mixing a polishing slurry with tetramethyl ammonium hydroxide and hydrogen peroxide . in an alternative embodiment , the modified slurry is formed by mixing a salt of tetramethyl ammonium with a base and with hydrogen peroxide to form the modified slurry . the improved slurry when used during the chemical mechanical polishing step of an integrated shallow trench isolation manufacturing process allows the reverse pattern , etch and clean steps to be eliminated prior to cmp .