| 摘要 |
<p>A double exposure process is disclosed whereby a first exposure produced by conventional photolithograpic techniques generates a latent negative image in a photoresist etch mask layer (22), the image subsequently employed to modulate a second exposure generated by the multiple beam interferometric lithography technique. Periodic surface relief structures (80) patterned by the second exposure and formed after development of the exposed photoresist material, are restricted to regions (52) defined by the initial exposure, with the photoresist material (54) outside these regions remaining unmodulated, or devoid of the periodic structures (80), and suitable for use as a mask in a subsequent etching process.</p> |
