Donor level of interstitial hydrogen in CdTe

The first results demonstrating the existence of a donor level of interstitial hydrogen in CdTe are presented. From the Arrhenius analysis, this donor level is characterized by an activation energy for electron emission ${E}_{\text{C}}\ensuremath{-}{E}_{\text{t}}=0.06\text{ }\text{eV}$ and a pre-exponential factor equal to $2\ifmmode\times\else\texttimes\fi{}{10}^{5}\text{ }{\text{s}}^{\ensuremath{-}1}\text{ }{\text{K}}^{2}$, and is observed after a low-temperature implantation with protons. Above 75 K the hydrogen-deep donor state is unstable converting to a more stable configuration which is believed to be a negatively charged form of isolated H. The results are analogous to what has been observed for interstitial hydrogen in GaAs.