Studies on structural, electrical, and optical properties of Cu doped As–Se–Te chalcogenide glasses

Abstract

Articles you may be interested inEffect of Zn incorporation on the optical properties of thin films of Se 85 Te 15 glassy alloy AIP Conf. Enhancement of photoluminescence intensity by photoinduced interdiffusion in nanolayered a -Se ∕ As 2 S 3 films J. Appl. Phys. 97, 044314 (2005); 10.1063/1.1853499 X-ray photoelectron spectroscopic investigation of surface chemistry of ternary As-S-Se chalcogenide glasses Cu doped chalcogenide ͑ChG͒ glassy films in the As-Se-Te glass system have been prepared using thermal evaporation techniques. Single-source evaporation from bulk ͑1−x͒ As 0.40 Se 0.35 Te 0.25 + x Cu glasses with x = 0.05, 0.075, 0.10, 0.125, and 0.15, as well as dual-source coevaporation from As-chalcogenide and Cu-chalcogenide binary glasses as source materials, has been explored. We have shown that it is not possible to deposit high concentration Cu doped ChG glassy films, from the Cu doped bulk samples using single-source evaporation. However, using the dual-source coevaporation technique, we have demonstrated that the films can be doped with high concentrations of Cu. Micro-Raman spectroscopy has been utilized to verify that Cu is introduced into the glass network without disrupting the basic As-chalcogen units. Optical measurements have shown that introduction of Cu decreases the band gap of As-Se-Te glasses. The electrical properties of the investigated films have been measured at different temperatures and it has been shown that Cu incorporation in the As-Se-Te glass system vastly improves electrical conductivity. Moreover, we have shown that the temperature dependence of electrical conductivity can be fitted assuming variable range hopping between states near the Fermi level.

High‐Conductivity Tellurium‐Based Infrared Transmitting Glasses and their Suitability for Bio‐Optical Detection

“…Large conductivity increases could be caused by the additions of additives, 10 although conductivities of amorphous semiconductors are generally much less sensitive to nonstoichiometry and the presence of impurities than are those of crystalline semiconductors. Copper is a commonly used dopant for enhancing the conductivities of chalcogenide glasses 11–13 . The major reason is that a large number of copper can be introduced into chalcogenide glasses and the metallic character can usually be increased efficiently.…”

Structural characterizations of As–Se–Te glasses

“…In the Raman spectrum, two intense bands develop at 168 and 205 cm −1 and become the main features at x = 2.5 for As 2 Se 3−x Te x (x = 2 for As 3 Se 7−x Te x ) glasses. The Raman band at 205 cm −1 can be attributed to vibrations of Se-Te bonds, as observed in the system Se 1−x Te x [28], or to As-Se vibration in mixed AsSe 3−x Te x units [29,30]. The latter proposition may contribute predominantly to this Raman band.…”

“…The latter proposition may contribute predominantly to this Raman band. The As-Te stretching in tellurium rich AsSe 3−x Te x entities (x ≥ 2) would give rise to the Raman band at 168 cm −1 [29,30]. The presence of Te-Te bonds are not expected from Raman analysis of the spectra which should have a signature at 150-155 cm −1 [28].…”

Aging process of photosensitive chalcogenide films deposited by electron beam deposition

“…The IR spectrum of the x = 20 glass shows its main band at 220 cm −1 . We attribute the Raman band at 205 cm −1 to vibrations of Se-Te bonds as observed in the system Se 1−x Te x [36] or to As-Se vibration in mixed AsSe 3−x Te x units [37,38]. The strong IR band at 220 cm −1 would be consistent with the formation of mixed AsSe 3−x Te x units, considering that the 3 mode of [AsSe 3/2 ] pyramids is active at 230 cm −1 (Fig.…”

“…1(d)). The Raman band at 168 cm −1 could be related to As-Te stretching in AsSe 3−x Te x entities [37,38].…”