Energization‐Time Dependence of Electrical Properties of Anodized n‐GaN Grown on Si Substrates

Abstract

With a view to device applications as a new material, n‐GaN grown on Si substrates is anodized at 4 V in an electrolyte solution for different energization times (15–240 min), and the dependence of the changes in electrical properties on the anodization time is evaluated. Anodization at 4 V increases the resistivity of n‐GaN with increasing energization time. To investigate the origin of the increase in resistivity by anodization, the results of the temperature dependence of the Hall mobility and electron density are discussed. The Hall mobility decreases with increasing energization time. The decrease in Hall mobility is because anodization forms neutral defects and increases neutral‐impurity scattering. The electron density decreases with increasing energization time. The decrease in electron density occurs because anodization deepens the original donor level and generates a deeper level that captures electrons. Thus, anodization changes the electrical properties of n‐GaN grown on Si substrate, and their dependence on energization time is discussed in detail.