Solid-state imaging devices having combined microlens and light dispersion layers for improved light gathering capability and methods of forming same

摘要

Solid-state imaging devices having combined microlens and light dispersion layers include a semiconductor substrate, a light transmission layer and an improved lens layer. The semiconductor substrate and light transmission layer collectively form an imaging substrate having a face thereon and a plurality of light sensing elements therein extending adjacent the face. The light transmission layer may include a first polarizing layer, an array of color filters and a second polarizing layer. The lens layer comprises an array of microlenses and a light dispersion layer. The preferred lens layer is formed on an upper face of the imaging substrate. The array of microlenses in the lens layer may be formed by reflowing a two- dimensional array of spaced photoresist regions (e.g., resist cylinders) as circular-shaped lenses having convex outer surfaces. A light dispersion layer is also preferably formed on the face of the imaging substrate. The light dispersion layer may be formed as a conformally deposited mesh-shaped layer having openings therein which are defined by the array of microlenses and having concave-shaped depressions therein which extend between adjacent microlenses. The light dispersion layer is preferably formed of a material having an index of refraction in a range between about 1.45 and 1.50 and the microlenses are preferably formed of a material having an index of refraction in a range between about 1.65 and 1.70.