Abstract: New photoresists and processes are required for sub0.15 $mu@m design rules and currently an importanteffort is on- going for single layer resistsoptimization at 193 nm. Top surface imaging can be aninteresting alternative approach. An all dry chemicalvapor deposition (CVD) process based on plasmapolymerized methylsilane (PPMS) or plasma polymerizeddimethylsilane (PP2MS) provides a thin conformal andphotosensitive layer at 193 nm. A thin amorphous filmof Si-Si bonded material is deposited using plasmaenhanced chemical vapor deposition with methylsilane ordimethylsilane as the gas precursor. Upon 193 nmexposure under air, photo-induced oxidation of the CVDresist occurs, generating a latent image. The image isthen developed in a chlorine-based plasma, providing anegative tone process. This mask can be used to patterna thick organic underlayer to provide a general bilevelprocess. Lithographic results on both a 193microstepper as well as a full field production stepperare presented: resolution down to 0.10 $mu@m equal L/Swas obtained. A preliminary comparison between PPMS andPP2MS materials is presented, including FTIR results,stability of the films in air and lithographicperformance including line edge roughness. !11
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