Tunability of optical properties of InSb films developed by pulsed laser deposition

Abstract

The InSb thin films were successfully prepared from binary alloy target by Pulsed Laser Deposition (PLD) onto heated Si/SiO2 substrates at various deposition temperatures (Td) ranging from room temperature to 400 °C. The evolutions of structural (XRD, XPS), microstructural (AFM, SEM) and optical (XPS, FTIR, RAMAN) properties as a function of deposition temperature were systematically taken into account. The analyzed results indicate that the films are well crystallized with Zinc Blende (ZB) structure for Td ≥ RT. Increasing Td induces significant signature of preferentially crystal orientations of (h11) accompanied by distinctive microstructural evolution from continuous fashion (Td ≤ 300 °C) to almost isolated islands feature (Td ≥ 350 °C). Derivations of crystallite sizes, lattice strain, dislocation density, Lotgering orientation factor, and root mean square roughness were correlated with Raman shift and XPS analysis, and optical properties. The developed thin films allow to observe the flexibility of optical band gap energy (from 0.18 eV to 0.50 eV), which is directly related to the quantum confinement effect coupled with the band-filling effect of Burstein–Moss shift.