Observation of multiple Er3+ sites in Er-implanted GaN by site-selective photoluminescence excitation spectroscopy

Abstract

Photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies have been carried out at 6 K on the 1540 nm I13/24→I15/24 emission of Er3+ in Er-implanted films of GaN grown by metalorganic chemical vapor deposition. The PLE spectra exhibit several broad below-gap absorption bands, which excite three distinct site-selective Er3+ PL spectra. The excitation of two of the site-selective Er PL bands involves optical absorption by defects or background impurities, rather than direct intra-f shell absorption, with subsequent nonradiative transfer of the energy to nearby Er3+ luminescence centers. The characteristics of the PLE spectrum of the third site-selective PL band suggest that an exciton bound at an Er-related trap is involved in the excitation mechanism.

Photoluminescence and Photoluminescence Excitation Spectroscopy of in Situ Er-Doped and Er-Implanted GaN Films Grown by Hydride Vapor Phase Epitaxy

“…In contrast, the PLE spectra 2(b) and 2(c) obtained from the Er-implanted HVPE-and MOCVD-grown samples, respectively, show only the broad, defect-or impurity-related absorption bands that are not attributable to Er 3+ . These absorption bands are characteristic of the implanted films only, suggesting that some of the broad absorption bands in the PLE spectra 2(b) and 2(c) are associated with defects or defect-impurity complexes created during the implantation and annealing procedures [1,3].…”

“…These Er-implanted HVPE-grown GaN films were annealed in a conventional tube furnace at 800 o C for 30 minutes in a flowing NH 3 /H 2 . For comparison, the GaN films grown on sapphire by atmospheric pressure MOCVD were implanted with a dosage of 4 x 10 13 ions/cm 2 at 280 keV [1][2][3][4]. The peak concentration of Er is 2 x 10 18 ions/cm 3 .…”

“…Photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopy have been performed to study the different structural configurations (sites or centers) on which Er 3+ ions are incorporated in Er-doped GaN and to investigate their excitation mechanisms [1][2][3][4][5][6][7]. Our previous study of site-selective PL and PLE spectroscopy in Er-implanted samples of GaN grown by metal organic chemical vapor deposition (MOCVD) that were annealed at 900 o C under a flow of N 2 revealed the existence of seven different Er 3+ sites [3].…”

Visible and Infrared Rare-Earth Activated Electroluminescence From Erbium Doped GaN

“…III-V semiconductors doped with rare-earth elements have also been used 10,11,12,13,14,15,16,17,18 and have advantages compared to narrow bandgap materials 19 . The advantage of Nakamura's devices is their extremely high quantum efficiency 1 (~5%), whereas RE doped devices offer multiple color emission, wavelength-limited only by the RE element(s) chosen and not by the band gap energy of the semiconductor.…”

Visible and Infrared Rare-Earth Activated Electroluminescence from Erbium Doped GaN

“…III-V semiconductors doped with rare-earth elements have also been used 10,11,12,13,14,15,16,17,18 and have advantages compared to narrow bandgap materials 19 . The advantage of Nakamura's devices is their extremely high quantum efficiency 1 (~5%), whereas RE doped devices offer multiple color emission, wavelength-limited only by the RE element(s) chosen and not by the band gap energy of the semiconductor.…”