摘要 |
Disclosed is a method of fabricating a phase shifting reticle in which phase shifters cover alternatively apertures of opaque light shielding chrome layer formed on a transparent glass plate. The opaque light shielding chrome layers are formed on a partial surface of the transparent glass plate. Both the opaque light shielding chrome layers and apertures thereof are covered with a thin silicon dioxide layer. A resist is applied on an entire surface of the thin silicon dioxide layer, followed by a patterning of the resist. The phase shifters of silicon dioxide are selectively formed in apertures of the resist pattern by use of a liquid phase epitaxial growth, after which the resist pattern is removed. The phase shifter has an even thickness and a flat surface so as to permit a precise optical phase shift. The liquid phase epitaxial growth is used at a low temperature so that no deformation and no peel of the opaque light shielding chrome layer is occurred. The thickness of the phase shifter may easily controlled due to a low growth rate of the silicon dioxide layer serving as the phase shifter. |