| 摘要 |
<p>A method of phase shift lithography includes forming a chromeless phase shift reticle (10) with a pattern of parallel, spaced phase shifters (14). An exposure energy (22) is directed through the phase shift reticle (10) and onto a target (18) having a layer resist (23) formed thereon. Following an initial exposure, the phase shift reticle (10) is rotated and the resist (23) is exposed a second time. The resist (23) is then developed to form features in areas of resist that have not been exposed. These areas correspond to the projected points of intersection (34) of the phase shifters (14). Using a positive tone resist, solid resist features are formed. These solid features can be used to form a mask (46) for etching the target (18) to form field emitter sites (38) for a field emission display. Using a negative tone resist, open areas are formed in the resist (23) and can be used to deposit a material on the substrate such as contacts (56) on a semiconducting substrate (48). The method of the invention can also be implemented using two different reticles (10) with intersecting patterns or using a single reticle (10) having intersecting phase shift areas.</p> |
