Band-gap engineering of Cd1 − xZnxTe films deposited by pulsed laser deposition

We demonstrate enhanced band-gap tunability in Cd1 − xZnxTe thin films (x = 0, 0.03, 0.06, 0.1, 0.2, or 1) fabricated directly from Cd1 − xZnxTe targets using pulsed laser deposition (PLD). All the Cd1 − xZnxTe films have uniform thicknesses of ~ 200 nm, crystalline sizes of ~ 20 nm, and are highly oriented in the [111] direction. The annealed Cd1 − xZnxTe targets allow better compositional control of the Cd1 − xZnxTe films than non-annealed targets. This new process using a single target with high compositional uniformity provides better tunability of the Cd1 − xZnxTe film lattice parameter (6.49 to 6.09 Å) and band gap (1.48 to 2.22 eV) by increasing the Zn concentration (x) from 0 to 1.