MCT infrared photodiodes on the basis of graded gap P-p heterojunction grown by MBE HgCdTe epilayers on GaAs

The measurement signal (S) to noise (N) ratio (S/N) of novel 128x128 FPA in temperature range 77 -130K was carried out. FPA for spectral range 8-12 mu m was fabricated by B+ implantation process into graded MCT P-p heterojunction with potential barrier. MCT P-p heterojunction with specific MCT composition throughout the thickness was grown by MBE on GaAs substrate by ellipsometric control in situ. The potential barrier was determined by the difference of MCT composition at absorber and p-n junction location layers and equal to Delta X-CdTe = 0,025. It was shown that based on P-p heterojunction FPA operated temperature and wavelength increases over routine one without P-p heterojunction.