The Electrical Properties of Al, ga1-Xn Thin Films Deposited on Si(111) Substrate by Chemical Solution Deposition Method

Abstract

AlxGa1-xN thin films with the GaN buffer layer was deposited on Si(111) substrate by chemical solution deposition (CSD) method. The objective of this research was to evaluate the electrical properties of AlxGa1-xN with variation of Al mole fraction. The source for Ga and Al were gallium oxide (Ga2O3) and aluminum oxide (Al2O3), respectively as group III precursors and radical nitrogen resulted by high temperature decomposition of nitrogen gas. The mole fractions of solutions were varied between 15 to 35%. The formed white crystal was dissolved in ethylene diamine to form gel with molarities of 3-6 M. Therefore, the gel was superimposed on substrates Si with spin-coater at speed of 1100 rpm. The formed layer was then sintered at temperature of 900 C o such that it decomposed at N2 gas environment to form AlxGa1-xN. The composition of films was measured by energy dispersive of x-ray (EDX) and the measured Al concentrations were in the range of 9.52% to 24.19%. The electrical transport of the films was measured by means of Hall effect measurement at room temperature. The Hall mobility decreases with the increase of aluminum (Al) concentration and decrease carbon concentration. The resistivity increases with the increase of Al concentration. From the Hall effects measurement the AlxGa1-xN films have n-type conduction originated from nitrogen vacancy.