Implant isolation of ZnO

Abstract

We study ion-irradiation-induced electrical isolation in n-type single-crystal ZnO epilayers. Emphasis is given to improving the thermal stability of isolation and obtaining a better understanding of the isolation mechanism. Results show that an increase in the dose of 2 MeV 16 O ions ͑up to ϳ2 orders of magnitude above the threshold isolation dose͒ and irradiation temperature ͑up to 350°C) has a relatively minor effect on the thermal stability of electrical isolation, which is limited to temperatures of ϳ300-400°C. An analysis of the temperature dependence of sheet resistance suggests that effective levels associated with irradiation-produced defects are rather shallow (Ͻ50 meV). For the case of implantation with keV Cr, Fe, or Ni ions, the evolution of sheet resistance with annealing temperature is consistent with defect-induced isolation, with a relatively minor effect of Cr, Fe, or Ni impurities on the thermal stability of isolation. Results also reveal a negligible ion-beam flux effect in the case of irradiation with 2 MeV 16 O ions, supporting high diffusivity of ion-beam-generated defects during ion irradiation and a very fast stabilization of collision cascade processes in ZnO. Based on these results, the mechanism for electrical isolation in ZnO by ion bombardment is discussed.

Polarization-induced two-dimensional electron gas at Zn1−xMgxO/ZnO heterointerface

“…Although some of these strong points overlap with another wide bandgap semiconductor GaN, particular advantages of ZnO include bulk growth capability, amenability to conventional chemical and plasma-etching techniques [2], low growth temperature, high radiation hardness [3], and nearly double exciton binding energy.…”

Role of diatomic hydrogen in the electronic structure of ZnO

“…41,42 , which has been explained by generation of ion irradiation-induced traps. The To clarify whether H1 and H2 in Fig.…”

Effect of annealing temperature on optical and electrical properties of nitrogen implanted p-type ZnMgO thin films

“…The excitonic effect of this wide-bandgap compound semiconductor can be controlled properly even above room temperature. Its high oscillator strength, radiation hardness, high temperature resistance, simple wet-chemical processability and high exciton-binding energy (which leads to low optical-gain thresholds) can replace GaN [10][11][12]. A ZnObased bipolar device requires p-type ZnO layer, however, achieving p-type doping in ZnO proves difficult due to its asymmetry, which originates from the compensation for intrinsic defects having low formation energy, self-compensation and low solubility of the dopants [13].…”