Device and method for making photomask assembly and photodetector device having light-collecting optical microstructure

摘要

An optical mask can be made by providing a transparent mask substrate; depositing a first layer of opaque material, forming an aperture in the first layer; depositing a second layer of transparent material, depositing a third layer of transparent material; patterning the third layer to produce a disc-shaped region, heating the third layer until the disc-shaped region reflows into a lens-shaped region and cross-links, depositing a fourth layer, patterning the fourth layer to produce a cavity extending to the surface of the lens-shaped region, and dry etching the end of the cavity until the second layer develops a shape corresponding to the lens-shaped region.

主权项

1. A semiconductor assembly, comprising:
an optical mask for use in fabricating a semiconductor device, the optical mask having an optical mask substrate comprising a first alignment indicator; a wafer comprising a second alignment indicator; and a refractive alignment lens etched into a glass layer, the glass layer having a first surface that is in contact with the optical mask substrate and an opposing surface that is in contact with the wafer to facilitate a visual alignment of the first alignment indicator with the second alignment indicator, wherein the refractive alignment lens is etched at a location on the glass layer that is aligned with a viewing axis extending between the first alignment indicator and the second alignment indicator, the location selected to configure the alignment lens to project an image of the second alignment indicator into the optical mask substrate and provide an effective distance that is smaller than an actual distance between the first alignment indicator and the second alignment indicator for overcoming a parallax effect when the second alignment indicator is viewed along the viewing axis during the visual alignment.