Growth and characterization of tin oxide thin films and fabrication of transparent p-SnO/n-ZnO p–n hetero junction

Abstract

Abstract p-Type and n-type tin oxide thin films were deposited by rf-magnetron sputtering of metal tin target by varying the oxygen pressure. Chemical composition of SnO thin film according to the intensity of the XPS peak is about 48.85% and 51.15% for tin and oxygen respectively. Nearest neighbor distance of the atoms calculated from SAED patterns is 2.9 Aand 2.7 Afor SnO and SnO 2 respectively. The Raman scattering spectrum obtained from SnO thin films showed two peaks, one at 113 cm −1 and the other at 211 cm −1 . Band gap of as-deposited SnO x thin films vary from 1.6 eV to 3.2 eV on varying the oxygen partial pressure from 3% to 30% which indicates the oxidization of metallic phase Sn to SnO and SnO 2 . p-Type conductivity of SnO thin films and n-type conductivity of SnO 2 thin films were confirmed through Hall coefficient measurement. Transparent p–n hetero junction fabricated in the structure glass/ITO/n-ZnO/p-SnO shows rectification with forward to reverse current ratio as 12 at 4.5 V.