| 摘要 |
<p>ICs are mfrd. by (a) forming superimposed first, second and third masking layers, selectively etchable w.r.t. each other, on a semiconductor substrate, (b) etching a set of openings in the first layer only (c) etching a first subset of openings within the set, through at least the second layer, using the first layer as a mask, while protecting remaining openings, (d) forming first regions in the substrate through the first subset of openings, and (e) similarly forming second and third regions using second and third subsets of openings. Regions are self-aligned and formed without undercutting, allowing reduced size of devices and reduced distance between them. -</p> |
