ETHYLIODIDE N-TYPE DOPING OF HG1-XCDXTE (X=0.24) GROWN BY METALORGANIC MOLECULAR-BEAM EPITAXY

Conductive n-type Hg1-xCdxTe epitaxial layers with x=0.24 were grown by metalorganic molecular beam epitaxy using iodine doping. Ethyliodide was chosen as the dopant precursor based on previous results obtained for CdTe. The low-temperature (20 K) electron concentration increased from an undoped level of ∼1015 cm-3 to 5×10 18 cm-3 for ethyliodide flow rates from 10-4 to 10 sccm. High electron mobilities were measured and secondary ion mass spectrometry measurements indicated a high degree of electrical activity. These results demonstrate that iodine is a highly effective n-type dopant for long-wavelength HgCdTe alloys and device structures. © 1994 American Institute of Physics.