The Influence of Annealing and Doping by Copper on Electrical Conductivity of CdTe Thin Films


In this research CdTe and CdTe: Cu thin films with different doping ratios (1, 2, 3, 4 and5) %, were deposited by thermal evaporation technique under vacuum on glass substrates atroom temperature in thickness 450 nm.The measurements of electrical conductivity (σ), and activation energies (Ea1, Ea2), havebeen investigated on (CdTe) thin films as a function of doping ratios, as well as the effect ofthe heat treatment at (373, 423, and 473) K° for one hour on these measurements werecalculated and all results are discussed.The electrical conductivity measurements show all films prepared contain two types oftransport mechanisms, and the electrical conductivity (σ) increases whereas the activationenergy (Ea) would decrease as the increasing (Cu) percentage in the sample except 5%. It isalso noticed that the electrical conductivity (σ) showed a decreasing trend with increasingannealing temperature, while the activation energies (Ea1, Ea2) showed opposite trend, wherethe activation energies increased with annealing temperature. Also the electrical conductivityvalues was found increased about 3- 4 orders when pure CdTe films are doped with (3, 4) %Cu and annealing at 473 K°.