A barrier structure optimization for widening processing window in dual-band HgCdTe IRFPAs detectors

Dual-band HgCdTe IRFPAs detectors are one of the most important developing frontiers for 3rd generation IRFPAs detectors. A barrier structure has been implemented in the dual-band HgCdTe detectors to restrain the electrical cross-talk between two layers with different compositions. Moreover, we now reveal another benefit of this barrier structure. This barrier can relieve the critical demands in photo-lithography of the implantation process, which shows great advantages as the dimension of a single element in advanced dual-band IRFPAs detectors is becoming less than 30 μm. When the implantation pattern migrates, the profile of the cavity in the dual-band structure is exposed under implantation. An n-type connection between LW layer and MW layer will be induced. With a modified barrier, the dark current of the MW contact can be reduced to the same order as those with precise implantation.