Microstructural and optical properties of CuIn3Te5 thin films for solar cells

Effect of tellurium deposition rate on the properties of Cu–In–Te based thin films and solar cells

“…As films (b) and (c) showed the same minimum values of E g , a high r Te above approximately 0.9 nm/s is essential to grow the CuIn 3 Te 5 thin films with a sharp absorption edge. The values of E g agree well with the reported values for CuIn 3 Te 5 (1.01-1.05 eV) [7,13]. As a result, the second absorption edges can be attributed to the transitions from the crystal-field split level to the conduction band minimum (CBM), and/or from the spin-orbit split level to the CBM [14].…”

“…Furthermore, the peculiar (2 0 2) and (2 1 2) lines of the defect chalcopyrite CuIn 3 Te 5 structure were slightly observed for film (d) even at a low substrate temperature of 200 1C. Because the peculiar lines of the CuIn 3 Te 5 structure were observed only at substrate temperatures above 300 1C [7], the effect of high r Te on a thin-film growth is similar to that of high temperature in terms of obtaining a single CuIn 3 Te 5 phase. This is in good agreement with the values of full width at half maximum (FWHM) of the (1 1 2) line, which were determined to be 0.3901 and 0.2321 for films (c) and (d), respectively.…”

“…However, there have thus far been few reports on the deposition and characterization of CuIn 3 Te 5 regarding its application as photovoltaic devices. Recently, we demonstrated a 4.6%-efficient Cu-In-Te based thin-film solar cell using a CuIn 3 Te 5 thin film (E g ¼1.01 eV) grown at a low substrate temperature of 200 1C [7]. The bandgaps of Cu-deficient CuInTe 2 such as CuIn 3 Te 5 and CuIn 5 Te 8 , with defect chalcopyrite structures known as ordered defect compounds or ordered vacancy compounds, are reported to increase slightly compared to those of CuInTe 2 [8].…”

Influence of copper to indium atomic ratio on the properties of Cu–In–Te based thin-film solar cells prepared by low-temperature co-evaporation

“…In this study, light soaking and air-annealing 11,17 were not performed prior to the J-V measurements. The CdS buffer layers were grown at 60 C by chemical bath deposition, 5 and the ZnO:Al/ZnO window layers were deposited without intentional substrate heating by rf-magnetron sputtering.…”

“…As previously reported in the literature, 11 the Raman spectra of the Cu-poor films (a)-(c) consist of a few broad peaks. 17 Although elemental Te was not detected by XRD in the films with Cu/In atomic ratios of 0.38-0.57, a small amount of Te phase can coexist at the surface of the films. As indicated by the closed symbols and dotted lines in Fig.…”