Properties of gallium-doped hydrogenated amorphous germanium

Electrodeposition of Crystalline Gallium‐Doped Germanium and SixGe1−x from an Ionic Liquid at Room Temperature

“…The band gap of (0.9 AE 0.1) eV corresponds well with the band gap of gallium-doped germanium reported in the literature (0.87 and 0.92 eV, depending on the doping concentration). [25] To evaluate the gallium concentration in germanium, XPS measurements were performed. Because, even after rinsing, small amounts of ionic liquids remained on the surface of the material, the samples were etched by argon sputtering before the XPS detailed spectra were acquired.…”

Bismuth doping of hydrogenated amorphous germanium thin films

“…[13,14]. Thermopower data indicate that Bi impurity always induces a dominant electron conduction, implying an n-type doping, as expected from a column V element [11].…”

“…The doping was performed by co-sputtering small, solid pieces of Bi together with the Ge target. Details on sample deposition parameters and film characterization are given in previous publications of the Campinas group [13,14]. Films of 10 − 4 cm typical thickness were deposited onto Corning 7059 glass and onto crystalline silicon substrates.…”

Local coordination of Ga impurity in hydrogenated amorphous germanium studied by extended x-ray absorption fine-structure spectroscopy

“…The increased disorder measured in the most doped sample might be related to some metallic segregation, known to exist at this Ga concentration. 6 The above results indicate the need to further investigate the role of the chemical specificity of dopants on the network relaxation around impurity sites.…”

“…The doping was performed by co-sputtering small, solid pieces of Ga together with the germanium target. 6 Typical film thickness is ϳ3 m. The total dopant concentration was inferred from proton-induced x-ray emission. 7 The EXAFS measurements were performed at the beam-line BM08 of the European Synchrotron Radiation Facility ͑ESRF͒ in Grenoble, France.…”