FIELD: semiconductor technology. SUBSTANCE: mask for projection of pattern on to semiconductor plate having stepped appearance has impenetrable pattern and substrate with steps matched with stepped structure of semiconductor plate. Steps have thickness which value depends on the square of magnification of projection lens and provides for phase difference 360°±5o between radiations passing through zone of step and zone without step. In agreement with one version of mask steps are made of pattern on optically transparent film. In process of manufacture of mask steps are formed by pickling or by application of optically transparent material on entire substrate of mask and fabrication of pattern on it. Layer of impenetrable material is applied before or after formation of steps from transparent material. Side walls of steps of substrate of mask are made perpendicular or in the form of stairs with assemblage of steps or with inclination. Inclination is produced by inclination pickling with use of inclination of material of photoresist or by formation of inclined spacer from transparent film. EFFECT: simplified process of manufacture of mask and of formation of pattern with high resolution. 23 cl, 22 dwg
Authors
Dates
2000-01-20—Published
1994-03-02—Filed