Deep levels have been characterized in n-type GaAs crystalline films grown by metalorganic chemical vapor deposition, doped in situ with 4d transition metal, rhodium, using the deep level transient spectroscopy (DLTS) technique. Two prominent broad bands of deep levels are found... (Read more)

p-type GaAs epilayers grown by metal-organic chemical vapour deposition (MOCVD) technique, doped in situ with rhodium (Rh) impurity, have been studied by deep level transient spectroscopy (DLTS). A composite peak consisting of emission signals from at least two deep levels in the lower-half band gap is identified with Rh. This peak is resolved using double-correlation DLTS (DDLTS) measurements, providing the clear energy positions of the Rh-related deep levels as E_v+0.35 eV and E_v+0.51 eV. Emission rate signatures and other parameters are reported for these deep levels. They are observed to show electric-field dependent emission signatures. No significant minority carrier (electron) deep level could be clearly identified with Rh due to the presence of significant inadvertent features in the injection DLTS spectrum. Results are compared with our earlier study of Rh-doped, n-type, MOCVD GaAs. (Read more)

Preliminary results on the study of deep levels associated with 4d-transition metal, rhodium, in crystalline GaAs grown by metal-organic chemical vapour deposition (MOCVD) technique are reported for the first time. Deep level transient spectroscopy on n-type GaAs doped in situ with Rh during MOCVD growth reveals a broad majority carrier emission peak. The peak corresponds to a band of deep levels extending over the energy range 0.57–0.65 eV below the conduction band edge with lower-energy states having lower electron capture cross-sections. The deep levels show a pronounced dependence of electron emission rate on the junction electric field. Minority carrier (hole) emission spectra at zero bias show a pronounced Rh-related deep-level peak with a low-temperature shoulder. The dominant level in the lower half-gap is found to have a position E_v+0.44 eV, with a field-dependent emission rate signature. (Read more)