Abstract: An improved method for preparing multiple-exposure photomasks having at least three levels of transmissivity is disclosed. A conventional bi-exposure photomask is first formed which contains a macroscopically exposed area, a microscopically exposed area, and a masked area on a transparent substrate. Then a diffractive-refractive light-scattering optical element is formed above the microscopically exposed area so as to provide an exposure area with an intermediate light transmissivity. In a preferred embodiment, the diffractive-refractive light-scattering optical element above the microscopically exposed area is formed by first forming a transparent positive photoresist above the bi-exposure photomask. The transparent positive photoresist is exposed to an irradiation from the bottom of the transparent substrate, and is developed. Finally, the transparent positive photoresist is heated to cause a melt-flow thereof which forms a concave optical element above the microscopically exposed area.

Abstract: A positive photoresist composition is disclosed which comprises a photosensitive compound, a phenolic resin, and an organic solvent. The phenolic resin is prepared from a monomeric composition comprises formaldehyde and a mixture of phenol monomers. The mixture of phenol monomers comprises: (a) no more than 98 mole percent of a mixture of monohydroxy phenols, the mixture of monohydroxy phenols comprises: (I) about 50.about.80 mole percent of meta-methylphenol; (ii) about 10.about.30 mole percent of 2,5-dimethylphenol; and (iii) about 10.about.40 mole percent of 2,3,5-trimethylphenol; and (b) at least 2 mol percent of at least one polyhydroxybenzene which is presented by the following formula: ##STR1## wherein n is an integer of 1 or 2. Preferably, the polyhydroxybenzene is a mixture of trihydroxybenzene and dihydroxybenzene in a molar ratio of about 40 to 60.

Abstract: An improved method is disclosed for making color filters via electrodeposition or lithographic electrodeposition of a plurality of colored resins onto an electrically conductive substrate. The method comprises the steps of: (a) forming a black-hued pattern on the substrate; (b) dividing the substrate into an intended zone and a conjugate zone, the intended zone being portions of the substrate to be deposited with the colored resins and the conjugate zone being portions of the substrate not to be deposited with the colored resins; (c) forming a permanent insulation film on the conjugate zone of the substrate; and (d) electrodepositing the colored resins onto the intended zone of the substrate.