Ding Ruijun

Progress on HgCdTe MBE for the application of IRFPAs

The progress on molecularbeam epitaxial growth of HgCdTe focusing on the requirements by the 3rd generation of infrared focal plane arrays are described. As large format HgCdTe IRFPAs demanded, the efforts on HgCdTe MBE on large area alternative substrates were presented, such as the improvement of crystalline quality, surface morphology, as well as Cd composition umiformity. The device fabrication on 512×512 MW and SW IRFPAs well demonstrated the performance of HgCdTe epi-layer. The studies of HgCdTe MBE on lattice-match substrates also were described, which were essential for the fabrication of LW and APD HgCdTe detectors. After growth condition optimized, the uniformity of epi-layer was greatly improved. On 10 mm HgCdTe/ZnCdTe( x =0.22), a typical value of FWHM of (422) X-ray diffraction was found to be less than 25 arcsec, as well as the best results of EPD reached 3×10 4 cm - 2 .

An Investigation on Spectral-Characteristic of HgCdTe two-color Detector

Some recent results of spectral-characteristic investigation on integrated HgCdTe infrared two-color detector are presented. Many discussions were focused on SWIR response of the preliminary two-color detector which exhibited a sharply peaked spectrum. The reason of SWIR abnormal spectrum was rooted out, and the way to solve the problem was obtained theoretically. Finally, the proper spectral responses of two-color detector with an improved structure were accomplished as expected.