HIGH-QUALITY PLANAR HGCDTE PHOTODIODES FABRICATED BY THE ORGANOMETALLIC EPITAXY (DIRECT ALLOY GROWTH-PROCESS)

Hg(1-x)Cd(x)Te, grown by the alloy organometallic vapor phase epitaxy technique, was used in the fabrication of p-n junction photodiodes. Hg(1-x)Cd(x)Te layers, capped with a CdTe cap, were grown in a continuous run by the direct alloy growth process. These layers were p type due to column II vacancies, with a concentration of 3-4 x 10(16)/cm3. n-type regions were obtained by selectively annealing the Hg(1-x)Cd(x)Te layer after opening windows in the CdTe cap layer. Vertical p-n junction diodes, with CdTe as the junction passivant, were thus formed in a planar configuration. Photodiodes, with cutoff wavelengths of 4.5-mu-m at 77 K, had R0A products in excess of 9 x 10(7) OMEGA-cm2.