Fabricating lens array structures for imaging devices

Claim 1

In a method of forming an integral lens assembly on a light-sensitive charge coupled device (CCD), which CCD defines a plurality of sensing elements, the lens array having a separate lens for each image sensing element, comprising the steps of: a) conformally coating the CCD to provide an SiO 2 layer which has peaks and valleys; b) depositing a layer of B 2 O 3 at a temperature selected to cause the B 2 O 3 to puddle and fill in all the valleys of the conformally coated layer; c) plasma etching the conformally coated SiO 2 layer and the B 2 O 3 layer at substantially the same rates until all of the deposited B 2 O 3 layer is removed to provide a planarized surface on the conformally coated layer; and d) depositing and patterning an inorganic color filter array structure on said planarized surface; e) depositing an SiO 2 "seed" layer on said color filter array; f) lithographically defining and plasma etching a seed structure; g) depositing a thick, conformal SiO 2 layer over the seed structure; and h) isotropically etching back to provide a lenslet structure.