  Strained layer superlattice (SLS) material system is a dynamic and relatively
new material for infrared detection. Large format, small-pitch and low-cost
focal plane arrays (FPAs) with more pixels are in demand for different
applications. For the current SLS based FPAs mesa etching are used to define
the pixels. For those SLS based FPAs with scaled pixel size making the mesa
structures can be challenging due to the need for deep etch, and then
passivation process. One of the possible solutions to address this issue is to
consider a planar structure and avoiding the mesa-isolation etching or complex
surface treatment/ passivation process. In this work, the recent progress on
planar SLS infrared photodetectors using ion-implantation for device isolation
is reviewed. In this method of fabrication, ion implantation was applied from
the top to bombardment the surface for device isolation, like mesa-isolation
step in device fabrication.
