Mechanisms of Damage Formation during Rare Earth Ion Implantation in Nitride Semiconductors

摘要

The damage generated in wurtzite nitride semiconductors (AIN, GaN, and InN) by 300 keV rare earth ions has been studied following implantation at room temperature of Eu from 10~(12) to above 10~(17) ions/cm~2. X-ray diffraction (XRD), transmission electron microscopy (TEM) and Rutherford backscattering (RBS) were used to investigate the evolution of damage and the deformation mechanisms versus the fluence. The behavior of the three compounds is clearly different; whereas InN breaks down at low fluences (～10~(12) ions/cm~2), it is shown that the damage formation mechanisms are similar in AIN and GaN. In both compounds, extended defects such as stacking faults play a critical role but exhibit different stability, as a consequence, GaN transforms to nanocrystalline state from the surface at a fluence of around 2.5 × 10~(15) ions/cm~2. In contrast, AIN amorphizes starting at the projected range (R_p), when the fluence exceeds 10~(17) ions/cm~2.