摘要 |
A technique generating sloping resist profiles based on an exposure process uses a reticle having structures surrounded with first and second contrasting interleaved bands below the resolution limit of the stepper used to expose the resist. Exemplary embodiments include a reticle having interleaved, non-overlapping transparent and opaque bands surrounding a transparent feature with an innermost one of the opaque bands bordering the structure, such as a via opening or a metal conductors pattern, resulting in the patterned photoresist having sloped or tapered sides with consistent reproducibility. The slope in the photoresist is then transferred to the underlying layer during an etch using the tapered photoresist as a mask. Alternatively, the sloped resist can have a negative slope angle for patterning metal conductors using a metal lift-off technique.
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