Structural, optical, and electrical properties of flash-evaporated copper indium diselenide thin films
- 288 Downloads
Copper indium diselenide (CuInSe2) compound was synthesized by reacting its elemental components, i.e., copper, indium, and selenium, in stoichiometric proportions (i.e., 1:1:2 with 5% excess selenium) in an evacuated quartz ampoule. Structural and compositional characterization of synthesized pulverized material confirms the polycrystalline nature of tetragonal phase and stoichiometry. CuInSe2 thin films were deposited on soda lime glass substrates kept at different temperatures (300–573 K) using flash evaporation technique. The effect of substrate temperature on structural, morphological, optical, and electrical properties of CuInSe2 thin films were investigated using X-ray diffraction analysis (XRD), atomic force microscopy (AFM), optical measurements (transmission and reflection), and Hall effect characterization techniques. XRD analysis revealed that CuInSe2 thin films deposited above 473 K exhibit (112) preferred orientation of grains. Transmission and reflectance measurements analysis suggests that CuInSe2 thin films deposited at different substrate temperatures have high absorption coefficient (~104 cm−1) and optical energy band gap in the range 0.93–1.02 eV. Results of electrical characterization showed that CuInSe2 thin films deposited at different substrate temperatures have p-type conductivity and hole mobility value in the range 19–136 cm2/Vs. Variation of energy band gap and resistivity of CuInSe2 thin films deposited at 523 K with thickness was also studied. The temperature dependence of electrical conductivity measurements showed that CuInSe2 film deposited at 523 K has an activation energy of ~30 meV.
KeywordsAtomic Force Microscope Substrate Temperature Hall Effect Measurement Soda Lime Glass Substrate CuInSe2 Film
N. M. Shah is grateful to University Grants Commission (UGC) (Western Region Office, Pune, India) for the award of teacher fellowship under “Faculty Improvement Program” in X plan. The authors also wish to thank UGC (New Delhi, India) for providing financial assistance through major research project.
- 2.Akl AAS, Ashour A, Ramadan AA, Abd El Hady K (2001) Vacuum 61:75Google Scholar
- 7.Huang CJ, Meen TH, Lai MY, Chen WR (2004) Sol Energy Mater Sol Cells 82:553Google Scholar
- 9.Ashour A (2006) J Mater Sci: Mater Electron 17:625Google Scholar
- 11.Barett CS (1953) Structure of Metals, Crystallographic methods, Principles and Data. McGraw-Hill, New York, p 156Google Scholar
- 20.Moulson AJ (1990) Electroceramics. Wiley, New York, p 26Google Scholar