Determination of the band gap depth profile of the penternary Cu(In(1−X)GaX)(SYSe(1−Y))2 chalcopyrite from its composition gradient

Abstract

The optical and vibrational properties of the quaternary chalcopyrite semiconductor alloy Ag x Cu 1x GaS 2

Deposition of In2S3 on Cu(In,Ga)(S,Se)2 thin film solar cell absorbers by spray ion layer gas reaction: Evidence of strong interfacial diffusion

“…Interestingly, no Ga-related XPS or Auger peaks can be observed, confirming the earlier reported accumulation of Ga exclusively at the Mo back contact. 17 As expected, distinct spectral features attributed to Na can also be identified. The small features attributed to O and C ͑which are ascribed to a minor surface contamination layer͒ are indicative for a rather clean sample surface.…”

Characterization of the Electronic and Chemical Structure at the Thin Film Solar Cell Interfaces: June 2005 -- June 2009

“…However, the estimated E g Surf values are higher than the expected bulk band gap (∼1.17 eV according to the quantum efficiency measurement of M2992 shown in Ref. 1) and the expected "theoretical" band gap [8] based on the here-determined surface Ga/(In+Ga) ratio (1.17 and 1.19 eV for sample M2992 and M2995, respectively). Our E g Surf finding is consistent with a Cu-deficient surface (found for both samples).…”

“…Using equation (6) (Ref. [8]) we have determined E g for the CIGSSe Surface to 1.68 eV and for the CIGSSe Back Surface to 1.58 eV (see Table IV). contaminants.…”

Towards efficient solar-to-hydrogen conversion: Fundamentals and recent progress in copper-based chalcogenide photocathodes

“…Of particular importance, the bandgaps of such copper-based chalcogenides can be easily tuned by forming different alloy compositions, which allows for delicate control of the band structures for alternative solar-to-energy conversion configurations. As shown in Figure 3, alloyed chalcopyrite semiconductors of Cu(In,Ga)(S,Se) 2 own the varied bandgaps in the range of 1.0-2.5 eV by tuning the In/(Ga + In) and S/(S + Se) molar ratios [40], and the opto-electronic property is closely related to the composition. Additional significant advantages of these chalcopyrite and kesterite semiconductors are the direct bandgap and high absorption coefficient, which indicate that their films with thickness less than 1 µm can absorb a substantial fraction of the incident photons.…”