Focal plane arrays in type II-superlattices

A method of preparing an infrared detector comprising the steps of:

• a) growing a type-II superlattice structure on a GaSb substrate;
• b) fabricating detector pixels;
• c) passivating the detector pixels with a passivation layer;
• d) patterning and etching the passivation layer;
• e) preparing metallic contacts;
• f) fabricate indium bumps;
• g) flip-chip bonding the substrate with a Si-based ROIC on a ROIC substrate or GaAs or InP based ROIC on a ROIC substrate;
• and
• h) underfilling between the substrate and the ROIC substrate;
• thereby creating an infrared Focal Plane Array detector based on a type-II superlattice.