Patent ID: 7402498

Claim:
A method of forming a trench isolation region comprising: forming a masking material over a semiconductor substrate; the masking material comprising at least one of tungsten, titanium nitride and amorphous carbon; forming an opening through the masking material and into the semiconductor substrate effective to form an isolation trench within semiconductive material of the semiconductor substrate; forming trench isolation material within the isolation trench and over the masking material outside of the trench effective to overfill the isolation trench, the trench isolation material comprising a silicon nitride-comprising layer having at least one material other than silicon nitride formed thereover; polishing the trench isolation material at least to an outermost surface of the at least one of tungsten, titanium nitride and amorphous carbon of the masking material; and after the polishing, etching the at least one of tungsten, titanium nitride and amorphous carbon from the substrate substantially selectively to the silicon nitride-comprising layer and etching all remaining of the masking material from the substrate.