Detecting Fermi-level shifts by Auger electron spectroscopy in Si and GaAs

High-Resolving Conical Electrostatic Energy Analyzer for Plasma Flows Investigations

“…Electron spectroscopy techniques, that originated many years ago, are currently being developed and applied for solving many scientific and technological problems. Judging by the number of recent publications these methods have shown very effective use in different areas: materials science [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Nuclear engineering [16][17][18][19].…”

Solution phase treatments of Sb2Se3 heterojunction photocathodes for improved water splitting performance

“…Several etchants have proven effective in removing the oxide layer on the Sb 2 Se 3 surface, of which (NH 4 ) 2 S was chosen as the most promising due to its very low toxicity, good solubility in water and high etching rates without requiring additional heating. 23 As observed in other chalcogenides such as GaAs and Cu(In,Ga)Se 2 , 23,24 (NH 4 ) 2 S is known to remove carbon impurities as well as the top oxide layer, which is often created as a result of dangling bonds' exposure to air at high temperatures during the selenisation process and thereafter until the overlayer is deposited. It could also incorporate sulphur onto the surface, which then passivates the dangling bonds on the surface.…”

“…It could also incorporate sulphur onto the surface, which then passivates the dangling bonds on the surface. 24,25 CuCl 2 has been shown to have an effect on the performance of Sb 2 Se 3 solar cells in a superstrate configuration (i.e. by modifying the Sb 2 Se 3 /Au interface); however, the reason for this improvement is debated.…”

“…22 It is well-known that at the semiconductor interface, the presence of surface states acts as trapping sites and recombination centres. 23,24 Therefore, simple, low-cost, and scalable solution-based treatments using earth-abundant chemicals with comparatively low toxicities were used in this study to passivate the above-mentioned surface states and, in turn, have better charge separation and reduced recombination. Several etchants have proven effective in removing the oxide layer on the Sb 2 Se 3 surface, of which (NH 4 ) 2 S was chosen as the most promising due to its very low toxicity, good solubility in water and high etching rates without requiring additional heating.…”

Impact of GaAs(100) surface preparation on EQE of AZO/Al2O3/p-GaAs photovoltaic structures

“…The air exposure of GaAs surface results in an immediate appearance of different oxides of various compositions (e.g., AsO, As 2 O, As 2 O 3 , GaO, Ga 2 O, Ga 2 O 3 , GaAsO 3 , and GaAsO 4 ) as well as of elemental arsenic [5][6][7]. The presence of an amorphous film of native oxides gives rise to midgap surface states in GaAs [8] which results in Fermi-level pinning [9]. Due to a high surface-related recombination velocity, a decrease in the photoluminescence (PL) of the semiconductor is also observed [7].…”