Time-resolved photoluminescence characterization of oxygen-related defect centers in AlN

Abstract

Time-resolved photoluminescence (PL) spectroscopy has been employed to investigate the emission characteristics of oxygen-related defects in AlN in the temperature region from 77 to 500 K. Two PL components with different decay constants are observed in the near-ultraviolet to visible regions. One is the PL component with decay time of <10 ns and its peak position shifts to longer wavelengths from $350 to $500 nm with increasing temperature up to 500 K. This PL component is attributed to the radiative relaxation of photoexcited electrons from the band-edge states to the ground state of the oxygen-related emission centers. In the time region from tens to hundreds of nanoseconds, the second PL component emerges in the wavelength region from 300 to 400 nm. The spectral shape and the decay profiles are hardly dependent on temperature. This temperature-independent PL component most likely results from the transfer of photoexcited electrons from the band-edge states to the localized excited state of the oxygen-related emission centers. These results provide a detailed insight into the radiative relaxation processes of the oxygen-related defect centers in AlN immediately after the photoexcitation process. Published by AIP Publishing.

Enhancement of the deep-level emission and its chemical origin in hexagonal boron nitride

“…This N 2 -treated A1 sample will be referred to as sample A2. It has been demonstrated that the IH method is quite useful to introduce defect-related emission centers in optically inert high-melting temperature materials such as a-Al 2 O 3 , 35,36 MgAl 2 O 4 spinel, 37 AlN, 38 and Mg 3 N 2.…”

“…The observed two decay time constants suggest the presence of trapping and detrapping processes of the photoexcited electrons via certain trap states during radiative recombination, as has often been observed in trap-related emissions in semiconductors 44 and insulators. 38,45 The temperature independent nature of the decay profile indicates that the excited electronic states are highly localized due to low electron-phonon coupling and will not compete with any of the nonradiative processes. This is consistent with the observation that the PL intensity in the NUV region (Շ3.5 eV) is hardly dependent on temperature (Fig.…”

Synthesis and photoluminescence characteristics of blue‐green luminescent aluminum oxynitride

“…We have recently demonstrated that the induction heating (IH) method is quite useful to introduce a large amount of intrinsic and intriguing emission centers in optically inert high‐melting temperature materials such as α‐Al 2 O 3 , MgAl 2 O 4 , (Ref) and AlN . Here, we further show that rapid IH enables direct nitridation of Al 2 O 3 even in the absence of AlN, forming micrometer‐sized AlON crystals with a broad photoluminescence (PL) band in the blue/green spectral region.…”

“…The bottom surface shows PL and PLE bands peaking at ~370 and ~250 nm, respectively. This UV/violet PL species (called species A, λ ex =~250 nm; λ em =~370 nm) is frequently observed in AlN and is commonly attributed to a deep‐level emission of defect complexes comprising V Al and O N , such as (V AlON ) − and (V AlON ) 2− . We hence consider that species A is attributed to a defect‐related deep‐level emission in AlN, which is formed during the carbothermal reduction at the near bottom surface.…”

Особенности Спектрально-Разрешенной Термолюминесценции В Облученных Микрокристаллах Нитрида Алюминия

“…[1][2][3][4][5][6][7]. Известны применения AlN для создания светодиодов и устройств поверхностных акустических волн, подложек для элементов электроники, детекторных сред для регистрации ионизирующего излучения различной природы [8][9][10][11][12][13][14]. Кроме того, микро-и наноструктуры AlN используются для создания компактных устройств на базе микролазеров УФ и видимого диапазонов [8,[15][16][17][18].…”