Optical characterization of low-energy nitrogen-ion doped GaAs

Autor: Kuniaki Tanaka, Tsutomu Iida, Kazuhiro Kudo, Hirokazu Sanpei, Yasushi Hoshino, Naoto Kobayashi, Takayuki Shima, Yunosuke Makita, Misao Yamaguchi, Adarsh Sandhu, Shinji Kimura
Rok vydání: 1997
Předmět:
Zdroj: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. :437-441
ISSN: 0168-583X
DOI: 10.1016/s0168-583x(96)01119-6
Popis: Optical characterization of nitrogen (N)-doped GaAs was performed by low-temperature photoluminescence (PL) measurements. N doping in GaAs was successfully made by irradiating low-energy (100 eV) N + ion beam during the growth of GaAs using the combined ion beam and molecular beam epitaxy (CIBMBE) system. For the sample with N + ion beam current density ( I N ) of 3 nA/cm 2 , which correspond to N concentration ([N]) of ∼5 × 10 17 cm −3 , two sharp PL emissions were observed at 1.508 eV ( X 1 ) and 1.495 eV ( X 2 ). For the sample with I N of 75 nA/cm 2 ([N] ≈ 1 × 10 19 cm −3 ), several novel PL emissions tentatively labeled by Y j ( j = 1, …, 8) were observed in the energy range of 1.491 – 1.449 eV by furnace annealing at 750°C for 20 min. Photoluminescence excitation measurements indicated that X 1 is correlated with the PL emission at 1.514 eV. Since the energy separation between individual Y j ( j = 1, …, 8) and X 2 is almost linear to r k −3 , where r k is the distance between nitrogen-nitrogen (NN) pairs, we ascribed X 2 and Y j as the radiative transition of excitons bound to isolated N and that to NN pairs, respectively.
Databáze: OpenAIRE
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