Thermal Pulse Annealing of Hg_1−xCd_xTe

Abstract

Thermal pulse annealing has been used to modify the near surface of Hg_1−xCd_xTe. Using anneals of approximately 260°C for seven seconds, the crystal quality of epitaxial HgCdTe surfaces can be improved as observed by MeV He⁺ ion channeling. Similar anneals have also been used to repair the damage resulting from a 250 keV, 10¹⁵¹¹B/cm² implant into HgCdTe held at LN₂. For higher temperatures and/or longer anneals, surface Hg loss is observed. Rutherford Backscattering measurements are used to measure this loss. The resulting loss rate data is described by N_□= A exp (−∆E/kT) where A and ∆E depend on the material composition with A = 10²⁹, ∆E = 1.8 eV and A = 10³⁶, ∆E = 2.6 eV for x = 0.23 and 0.4, respectively.