ESR Studies of Annealing Behavior of Nitrogen-Implanted GaP

Abstract

Annealing behavior (up to 1000°C) of nitrogen-implanted GaP has been studied using an ESR technique. The spectrum for samples as implanted is symmetrical, Lorentzian and isotropic, and its g-value = 2.0032 ± 0.0004, the line width ΔHms1~6 gauss, which is due to the disordered state. Two recovery stages have been observed in the isochronal annealing curve. The activation energy for the first stage (up to 150°C) is 0.22 – 0.23 eV, and for the second (300 – 500°C) is 1.40 – 1.50 eV. The spectrum anneals out at ~500°C. On the other hand, some weak lines due to the anisotropic damage centers have appeared after the ~100°C anneal. Moreover, the other structural line which is enhanced by illumination at 4920 or 7050 Å has been detected. After the 700 or 750 °C anneal, the hyperfine spectrum of the implanted N¹⁴ (with illumination at 5180 or 7050 A at 4.2 K) which is evidenced 3 lines centered about a g-value of 2.017, and the spectrum due to the secondary defects of which g-value is 2.0030 ± 0.0004 and ΔHms1~6 gauss have been detected.