Praseodymium added GaAs liquid phase epitaxy and its Schottky diode application

摘要

Pr_2O_3-added GaAs liquid phase eptiaxy (LPE) has been stuided. Due to the gettering effect of the rare earth (RE) elements low oxide surfaces and high pruity GaAs eplayers are obtained and examined. After epitaxial growth, the samples are prepared by a standard Schottky diode (SD) fabrication process. The variations in the el3ectrical properties of these SDs are reported. For an embodiment with a Schottky barrier ehgith (SBH) above 0.94 eV, a leakage current of around 0.7×10~-6 A and breakdown voltage of 14 V is obtained at a Pr_2O_3 addition ratio of 0.05 mg per gram of gallium. These SDs were also irradiated by gamma rays for study of radiaion hardness. After 4 h irradiation, all samples are initially out of function. However, 4 h later, due to natural annealing, the Pr_2O_3-added samples can recover up to 72/100 of their original SBH jvalues. Furthermore, after a further 24 h, the tendency to recover is saturated and a 17/100 SBH retardation still remains. During this period, the appropriate Pr_2O_3-added SDs (#508 & # 509) show better radiation hardness than the one (# 501) with no addition.