Diffractive micirolens array monolithic integration with PtSi focal plane array

Diffractive microlens arrays can completely collect the light at the focal plane and concentrate it into a smaller spot size on the detector plane, th e photodetector area can be substantially reduced. Increased gamma radiatio n hardening and noise reduction result from the decrease in photodetector s ensitive area. The diffractive microlens arrays have been designed by consi dering the correlative optical and processing parameters for PtSi focal pla ne array. They have been fabricated on the backside of PtSi focal plane arr ay chip by successive photolithography and Ar+ ion-beam-etching technique. The alignment of microlens array with PtSi focal plane array was completed by a backside aligner with IR light source. The practical processes and fab rication method are discussed. The performance parameters of PtSi FPA with diffractive microlens array are presented.