Fabrication and Characterization of Wavelength Selective Microbolometers using a Planar Self-aligned Process for Low Deformation Membranes

We present fabrication and characterization of wavelength selective germanium dielectric supported microbolometers using a self-alignment technique to help insure a flat microbolometer membrane. The fabricated microbolometer consists of a resistive absorber sheet on a quarter wavelength germanium layer above a half wavelength air gap, producing dielectric interference [1]. We use a self-aligned process without a polyimide patterning process that helps eliminate deformation and stress in the structure membrane. We demonstrated that the fabricated wavelength selective microbolometers have flat, robust membranes and produce excellent tunable narrowband absorption in MWIR/LWIR band with efficient multi-color IR spectral response using wavelength selective pixels.