Activation energy and density of states of CdTe thin films from temperature dependent I– V measurements

• Published in: Materials chemistry and physics 2011-05, Vol.127 (1), p.296-299
• Main Authors: Babkair, Saeed Salem, Ansari, Azhar Ahmad, Al-Twarqi, Najat Mohamed
• Format: Article
• Language: English
• Subjects: Activation energy; Aluminum; Cadmium tellurides; CdTe; Conduction mechanism; Density; Density of states; Electrodes; Evaporation; Ohmic; SCLC mechanism; Thin films
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2011.02.008

► Thermally evaporated CdTe films exhibit space charge limited conduction over a temperature range of 220–440 K at higher voltages. ► The characteristic temperature is determined as 380 K. ► The calculated density of traps distribution is 1.18 × 10 23 m −3 eV −1. ► The activation energy of traps determined from the I– V– T measurements is found to be 0.5 eV. I– V– T measurements performed on thermally evaporated CdTe films sandwiched between Aluminum electrodes have been reported over the temperature range of 220–440 K. I– V– T characteristics reveal an ohmic behavior at low biases followed by a SCLC mechanism indicating an exponential distribution of traps. The characteristic temperature of these traps has been estimated at 380 K. The density of these traps and their activation energy has been found to 1.18 × 10 23 m −3 eV −1 and 0.5 eV respectively.