Identification of the volatile decomposition products produced in the deposition of (Hg,Cd)Te by MOVPE

Abstract

Abstract The pyrolysis reactions of di‐isopropyl telluride and dimethyl cadmium, both alone and in combination and with and without mercury, have been studied using the technique of gas chromatography–mass spectrometry (GC–MS). For example, when mercury and dimethyl cadmium are mixed in hydrogen at the growth temperature (370°C), the volatile products observed are methane, ethane and dimethyl mercury. In contrast, when di‐isopropyl tellurideis substituted for the cadmium precursor in this reaction, the products observed are propane, propene and 2,3‐dimethylbutane with no volatile mercury‐containing compounds. Heating the two organometallic precursors together at the growth temperature in the absence of mercury gives products expected from the pyrolysis of each one alone plus a number of interaction products such as 2‐methylpropane. The results of these studies will be presented, a mechanism for the reactions proposed and the implications for MOVPE growth discussed.