| CPC G03F 7/70633 (2013.01) [G03F 7/70683 (2013.01); H01L 23/544 (2013.01)] | 8 Claims |

|
1. A system for manufacturing a semiconductor structure, comprising:
fabrication equipment, configured to form a first overlay mark and a second overlay mark on two different layers of a wafer respectively and to form a photoluminescent layer only on the first overlay mark, wherein the two different layers of the wafer are positioned at different elevations, wherein the photoluminescent layer is made of a photoluminescent material; and
alignment equipment, configured to detect an alignment of the first overlay mark and the second overlay mark at different elevations on the wafer, the alignment equipment comprising:
a stage, configured to support the wafer;
an optical device, configured to emit a first radiation on the photoluminescent layer to excite the photoluminescent material of the photoluminescent layer on the first overlay mark;
an optical filter, configured to receive and filter a second radiation emitted from the photoluminescent material, wherein the second radiation emitted from the photoluminescent material is a result of radiation relaxation of the photoluminescent layer after the photoluminescent layer is excited;
an optical detector, configured to convert the second radiation as a resulted optical signal filtered by the optical filter to an electrical signal; and
a controller configured to generate an alignment result of the first overlay mark and the second overlay mark generated based on the electrical signal from the optical detector.
|