Photoluminescence studies of arsenic-doped Hg1−xCdxTe epilayers

Abstract

Arsenic incorporation in HgCdTe epilayers has been achieved with a nonconventional radio frequency plasma source during molecular beam epitaxial growth. Photoluminescence studies were carried out on HgCdTe arsenic-doped samples. Measurements were done on the as-grown sample, after a Hg vacancy filling annealing and after a 400 °C activation annealing under Hg pressure. A comparison with extended x-ray absorption fine structure results allows us to assign the observed optical transitions to the Hg vacancies, As2Te3 glass and AsHg dopants. An optical signature of the arsenic site transfer upon activation annealing is found.

Photoluminescence in Mercury Cadmium Telluride – a Historical Perspective. Part I: 1966-1996

“…Before annealing, the dominating PL peak was broadened and shifted towards lower energies in respect to E g , which indicated the dominance of recombination via a shallow acceptor associated with mercury vacancies. This made it possible to estimate the level of the acceptor E A , which equaled 12 meV (above the valence band) for x = 0.216 and 19 meV for x = 0.234, consistent with other observations [10][11][12][13].…”

“…The authors believed that this acceptor was either an Au substitutional atom (some samples were Au-doped), or an alloy vacancy. Based on the current knowledge, we can assume that this acceptor was, indeed, a mercury vacancy, as its binding energy E a ~14 meV was confirmed since then in numerous PL studies [11][12][13]. The presence of a BE peak in MCT samples with x = 0.48 was explained by the longer lifetime of Auger recombination than that of radiative recombination.…”

Structural, optical, photoluminescence, dielectric and electrical studies of vacuum-evaporated CdTe thin films

“…The growth of high-quality and low-cost CdTe polycrystalline thin films for producing high conversion efficiency solar cells is the current topic of research. CdTe/CdS solar cells are one of the prospective candidates for widespread commercial * Author for correspondence (mskhan@jmi.ac.in) success in solar energy conversion and also for use as a substrate for the important infrared detector material HgCdTe, dilute magnetic semiconductor, epitaxial layers and quantum well structures (Morales-Acevedo 2006;Robin et al 2009).…”

Photoluminescence in Mercury Cadmium Telluride – a Historical Retrospective. Part II: 2004–2022

“…One of the first modern works of French scientists from Département Optronique at LETI, CEA on PL in MCT was the 2009 journal paper by Robin et al [13]. It was devoted to the study of Hg1-xCdxTe films with x = 0.3 grown by MBE on ZnCdTe substrates and doped with arsenic.…”

“…The high energy (HE) peak located at 245 meV was assigned to interband transitions; this peak did not shift after the annealing. Robin et al [13] believed that the low-energy (LE) and mid-energy (ME) peaks (located at 239 and 230.2 meV in as-grown films, respectively) had a different nature in the sample before and after the annealing. Namely, in the as-grown film the LE peak was attributed to the presence of VHg, while after VF annealing, to the AsHg complex, which was also an acceptor.…”