128-x128-element silicon microlens array fabricated by ion beam etching for PtSi IRCCD

A silicon refractive microlens array mounted on a 128-x128-element PtSi IR CCD focal-plane architecture is fabricated using a multiple-process, including photolithography, heat treatment, and argon ion beam etching techniques. The optical filling factor of PtSi IR CCD with refractive microlens array is more than 95 percent. The focal length of the square-base arch silicon microlens is' about 90 mu m. Both the scanning electron microscope and the surface style measurement are carried out to determine the dimensions and the surface morphology of silicon refractive microlens. The matching properties between the preshaped photoresist mask and silicon substrate during argon ion beam etching are given. The techniques utilized can be applied to fabricate microtips array and microplateforms (circle microtips) array.