TY - JOUR
T1 - Interplay of carriers and deep-level recombination centers of 275-nm light-emitting diodes — Analysis on the parasitic peaks over wide ranges of temperature and injection density
AU - Wu, Tingzhu
AU - Lin, Yue
AU - Peng, Zhangbao
AU - Chen, Huashan
AU - Shangguan, Zhibin
AU - Liu, Meng
AU - Chen, Sung Wen Huang
AU - Lin, Chih Hao
AU - Kuo, Hao-Chung
AU - Chen, Zhong
PY - 2019/8/5
Y1 - 2019/8/5
N2 - The low luminance efficiency, poor reliability and parasitic peaks have greatly limited the commercialization of deep ultraviolet (DUV) light-emitting diodes. Tasks of identifying the culprits of these deficits are of paramount importance but remains unaccomplished. We employ the full-range temperature (20 K - 300 K) measurement on 275-nm DUV devices that subjected to a 15-hour current-stress aging. The results suggest that the primary culprit of fast luminous decay is the proliferation of non-radiative centers. The origins of two main parasitic peaks are identified. The 310-nm peak is considered to solely come from deep-level radiative centers (DLRCs) that only dwell in the active region. Whereas, the 400-nm peak is proven to be dual-sources. One is related to the DLRCs in the active region, which only can be observed at very low currents; the other emerging at higher currents are associated with similar kinds of DLRCs located in the p-region, which only are excited when electrons overflow. This new discovery also demonstrates that a thorough investigation on the interplay among carriers and various types of defects should be conducted on the basis of the measurement that is taken under a wide temperature range, as well as under a proper forward voltage. This is to let the quasi-Fermi level shift across deep defect levels, the band-edge, and to over-band, whereby these recombination sites are exposed to deficit, moderate and saturated electron environment so that their natures can be well tested.
AB - The low luminance efficiency, poor reliability and parasitic peaks have greatly limited the commercialization of deep ultraviolet (DUV) light-emitting diodes. Tasks of identifying the culprits of these deficits are of paramount importance but remains unaccomplished. We employ the full-range temperature (20 K - 300 K) measurement on 275-nm DUV devices that subjected to a 15-hour current-stress aging. The results suggest that the primary culprit of fast luminous decay is the proliferation of non-radiative centers. The origins of two main parasitic peaks are identified. The 310-nm peak is considered to solely come from deep-level radiative centers (DLRCs) that only dwell in the active region. Whereas, the 400-nm peak is proven to be dual-sources. One is related to the DLRCs in the active region, which only can be observed at very low currents; the other emerging at higher currents are associated with similar kinds of DLRCs located in the p-region, which only are excited when electrons overflow. This new discovery also demonstrates that a thorough investigation on the interplay among carriers and various types of defects should be conducted on the basis of the measurement that is taken under a wide temperature range, as well as under a proper forward voltage. This is to let the quasi-Fermi level shift across deep defect levels, the band-edge, and to over-band, whereby these recombination sites are exposed to deficit, moderate and saturated electron environment so that their natures can be well tested.
UR - http://www.scopus.com/inward/record.url?scp=85070333005&partnerID=8YFLogxK
U2 - 10.1364/OE.27.0A1060
DO - 10.1364/OE.27.0A1060
M3 - Article
C2 - 31510491
AN - SCOPUS:85070333005
VL - 27
SP - A1060-A1073
JO - Optics Express
JF - Optics Express
SN - 1094-4087
IS - 16
ER -