Patent ID: 9520525
Filing Date: 2016-12-13
CPC Classification: H01L,Y02E

Claim Text:
1. A method of making an optical detector, the method including: forming a first optical absorber material on or adjacent a substrate; etching recesses into the first optical absorber material to define a set of multiple discrete absorber regions formed of said first optical absorber material, each discrete absorber region having a geometric shape which it shares in common with the other discrete absorber regions, the common geometric shape having four sloping sidewalls which angle towards a tip of said common geometric shape, a combined volume of the discrete absorber regions being smaller than a volume of etched recesses; and forming a metal reflector in contact with the tips of the discrete absorber regions forming a second optical absorber material directly on said substrate with said first optical absorber material being formed on or adjacent said second optical absorber material; and wherein the substrate is formed of GaAs, the first optical absorber material is formed of InAsSb, InSb, or InGaAsSb and the second optical absorber material is formed of InAlAsSb or InGaAsSb.