Type conversion of CdxHg1-xTe grown by liquid phase epitaxy

The process of p to n conversion in CdxHg1-xTe (CMT) is important to both photodiode and photoconductor device fabrication. It is the purpose of this work to investigate type conversion of CMT as a result of annealing in Hg vapour. p-type CMT grown by liquid phase epitaxy(LPE), and with x = 0.22 ± 0.02, has been annealed in an open-flow furnace at 200 °C. A Hall and strip technique has been used to identify the resultant p/n junctions, formed by Hg diffusing into the CMT and reducing the concentration of metal vacancies. Junction depths are found to be dependent upon the square root of anneal time, the initial acceptor concentration, Na, and background donor concentration, Nd. These findings are compared with other published data, and the mechanism of mercury diffusion is discussed with regard to Na and Nd, as well as Te precipitates.