The effect of Se/Te ratio on transient absorption behavior and nonlinear absorption properties of CuIn0.7Ga0.3(Se1-xTex)(2) (0 <= x <= 1) amorphous semiconductor thin films
Artikel i vetenskaplig tidskrift, 2017

The characterization of the CuInSe2 (CIS), CuInGaSe (CIGS) and CuGaSe2 (CGS) based semiconductor thin films are very important role for solar cell and various nonlinear optical applications. In this paper, the amorphous CuIn0.7Ga0.3(Se1-xTex)(2) semiconductor thin films (0 <= x <= 1) were prepared with 60 nm thicknesses by using vacuum evaporation technique. The nonlinear absorption properties and ultrafast transient characteristics were investigated by using open aperture Z-scan and ultrafast pump-probe techniques. The energy bandgap values were calculated by using linear absorption spectra. The bandgap values are found to be varying from 0.67 eV to 1.25 eV for Culn(0.7)Ga(0.3)Te(2), Culn(0.7)Ga(0.3)Se(1.6)Te(0.4), Culn(0).7Ga0.3Se1-xTe1.6 and Culn(0.7)Ga(0.3)Se(2) thin films. The energy bandgap values decrease with increasing telluride (Te) doping ratio in mixed Culn(0.7)Ga(0.3)(Se1-xTex)(2) films. This affects nonlinear characteristics and ultrafast dynamics of amorphous thin films. Ultrafast pump-probe experiments indicated that decreasing of bandgap values with increasing the Te amount switches from the excited state absorption signals to ultrafast bleaching signals. Open aperture Z-scan experiments show that nonlinear absorption properties enhance with decreasing bandgaps values for 65 ps pulse duration at 1064 nm. Highest nonlinear absorption coefficient was found for Culn(0.7)Ga(0.3)Te(2) thin film due to having the smallest energy bandgap. (C) 2017 Elsevier B.V. All rights reserved.

improved performance

precursors

Z-scan

selenization

Optics

Amorphous thin films

growth

Ultrafast pump-probe

temperature

laser

Materials Science

Semiconductor

solar-cells

annealing

tellurium te

saturable-absorber mirror

deposition

Nonlinear absorption

Författare

A. Karatay

Betül Kücüköz

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Fysikalisk kemi

G. Cankaya

A. Ates

A. Elmali

Optical Materials

0925-3467 (ISSN)

Vol. 73 20-24

Drivkrafter

Hållbar utveckling

Styrkeområden

Building Futures

Ämneskategorier

Kemiteknik

Kemi

DOI

10.1016/j.optmat.2017.07.046