A novel process for using a hard mask or protective layer in conjunction with an extremely thin photoresist is provided. In this process, a thin film of the protective layer is coated on the surface of a substrate that is to be selectively modified by reactive ion etch (RIE). The protective layer is photosensitive and anti-reflective. An extremely thin photoresist layer is coated on top of the protective layer. The stack of the films is selectively exposed to actinic radiation at a wavelength determined by the sensitivities of the protective layer and photoresist layer. The latent images on the photoresist and protective layers resulting from the exposure are developed with a common alkaline developer. The three dimensional patterns of photoresist and underlying protective layer are formed simultaneously by the single exposure and single development. When the underlying substrate is etched by RIE, the protective layer is the masking layer, not the photoresist.