Method for Manufacturing a Biometric Imaging Device by Means of Nanoimprint Lithography

Abstract

The present disclosure relates to a method for fabrication of an optical sensor for use in an image recognition device, e.g. a biometric imaging device, such as a fingerprint detector, for use in under-display applications. The presently disclosed method provides a cost-efficient fabrication process, preferably employing nanoimprint lithography, for realizing an optical sensor with improved light transmittance in a compact and cost-efficient structure. In particular the presently disclosed image recognition device can be placed under a display panel of an electronic device, such as a smartphone. One embodiment relates to a method for manufacturing a biometric imaging device, the method comprising the steps of: providing an image sensor comprising a photodetector pixel array; forming an opaque layer on the first transparent substrate layer or on the photodetector pixel array, the opaque layer having a transparent pinhole array therein; arranging a second transparent substrate layer on top of the opaque layer, and forming a microlens array in the top of the second transparent substrate layer, such that each microlens in the array corresponds to a pinhole in the pinhole array and at least one pixel in the photodetector array, wherein the opaque layer with the transparent pinhole array and the microlens array is formed by means of nanoimprint lithography, such as UV based nanoimprint lithography.

Dependencies are inferred from the claim text.