p -ZnO/n-GaN heterostructure ZnO light-emitting diodes

Abstract

We report on the characteristics of a ZnO light-emitting diode (LED) comprised of a heterostructure of p-ZnO/n-GaN. The LED structure consisted of a phosphorus doped p-ZnO film with a hole concentration of 6.68×1017cm−3 and a Si-doped n-GaN film with an electron concentration of 1.1×1018cm−3. The I–V of the LED showed a threshold voltage of 5.4 V and an electroluminescence (EL) emission of 409 nm at room temperature. The EL emission peak at 409 nm was attributed to the band gap of p-ZnO which was reduced as the result of the band offset at the interface of p-ZnO and n-GaN.

ZnO nanorod/GaN light-emitting diodes: The origin of yellow and violet emission bands under reverse and forward bias

“…23 However, very different behavior has been reported for pGaN/n-ZnO devices even for similar device architectures, which makes it difficult to establish strategies for the improvement of device performance. For example, in addition to devices lighting up under forward bias, devices lighting up under reverse bias 4, [8][9][10]12,13,28 have been reported.…”

“…2 and 3) and interfacial recombinations, 2 recombination on defects in p-GaN, 17 shift due to the energy band offsets in n-GaN/pZnO heterojunction, 23 as well as the presence of interfacial layer resulting in charge accumulation and bandgap renormalization. 27 Similar to yellow-orange emission, from the presence of this emission in the absence of ZnO, violet emission likely originates from p-GaN structures.…”

Band alignment of TiO2/FTO interface determined by X-ray photoelectron spectroscopy: Effect of annealing

“…Current-voltage test has verified that the band alignment has a significant effect on the current transport of the heterojunction. C Heterojunction structure is a very popular strategy in the preparation of various semiconductor optoelectronic devices for some specific reasons, such as photovoltaic solar cell, [1][2][3] laser diode (LD), [4][5][6] light emitting diode (LED), [7][8][9] and high-electron-mobility transistor (HEMTs). [10][11][12] Because of the differences in band gaps and work functions of the two materials, conduction band offset (∆E C ) and valance band offset (∆E V ) often form in the interface of the heterojunction, which will give a significant impact on the charge transport and carrier recombination of the devices.…”

Effect of Temperature Dependence on Electrical Characterization of <i>p-n</i> GaN Diode Fabricated by RF Magnetron Sputtering

“…A good diode is expected to have small temperature dependence in ideality factor. So, the observed high ideality factor could be due to several reasons such as accelerated recombination of electrons and holes in depletion region, the presence of interfacial layer, and the imperfections which may be due to the presence of crystalline and amorphousregions [5] [6].…”

“…Hwang et al examined the characteristics of light-emitting diode comprised of p-ZnO/n-GaN hetero junction. The threshold voltage and leakage current were found at 5.4 V and 2 × 10 −4 A, respectively [6]. Liu et al investigated the In GaN-based light-emitting diode with a p-n GaN homojunction.…”