The invention relates to the technical field of
semiconductor manufacturing and in particular relates to a burr-free photoetching method. The burr-free photoetching method comprises the following steps: S1, after pre-treating a
wafer,
coating the
wafer with one layer of negative
photoresist; carrying out selective
exposure on the negative
photoresist through a photoetching
mask, wherein the
exposure dosage of a photoetching
machine is 100mj to 150mj and the focal distance deviation value is less than 1mu m; S2, carrying out first time of rotary covering and immersing type development on the exposed
wafer, wherein the development time is 40s to 60s; S3, carrying out second time of rotary covering and immersing type development on the wafer after step S2, wherein the development time is 40sto 60s. According to properties of the negative
photoresist, the negative photoresist can form a pattern better through limiting the
exposure dosage, a exposure focal distance and time of 2 to 3 timesof the rotary covering and immersing type development, the pattern is wide in top and narrow in bottom and a lower layer of the pattern is concave inward;
metal is not continuously distributed on thewhole photoresist in an
evaporation process, so that a condition that the lower layer of the photoresist is stuck with the
metal is avoided and a degummed
metal layer is smooth and has no burrs; theelectrical property of appliances is improved and the yield of the appliances is improved.