- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Stress Relaxation in Porous GaN Prepared by UV Assisted Electrochemical Etching
摘要： This study describes the stress relaxation in porous GaN grown on Al2O3 substrates. The results indicate that the stress relaxation has taken place in the samples which increases by increasing the etching current. As compared to the as-grown GaN films, porous GaN exhibits substantial photoluminescence (PL) intensity enhancement with red-shifted band-edge peaks associated with the relaxation of the compressive stress. The red shifted phonon energy peak (E2) in the Raman spectra of the porous GaN films confirms further such a stress relaxation. Scanning electron microscopy (SEM) demonstrates that, the current density has significant effect on the size and shape of the pores.
关键词： Stress relaxation,Porous GaN,Raman spectroscopy,Red shift
更新于2025-09-19 17:15:36
-
From bulk to porous GaN crystal: precise structural control and its application in ultraviolet photodetectors
摘要： Porous GaN has many unique merits, such as a large specific surface area, adjustable bandgap and excellent optical performance. Here, we develop a simple and effective method for preparing porous GaN single crystals through high temperature annealing. The effects of different annealing temperatures on the porous structure, crystal quality and optical properties of GaN are investigated. The relationship model of annealing temperatures, times and GaN porous structures is summarized. An ultraviolet (UV) photodetector based on porous GaN is fabricated. The effects of porous structures on the performance of the GaN UV photodetector are investigated for the first time. We found that the appropriate GaN porous structure can improve the performance of the photodetector. A possible performance enhancement mechanism has been proposed. Based on the high performance and simple fabrication process, porous GaN crystal can be an excellent candidate for UV photodetectors.
关键词： optical properties,crystal quality,UV photodetector,high temperature annealing,porous GaN
更新于2025-09-16 10:30:52
-
Enhanced excitonic emission efficiency in porous GaN
摘要： We investigate the optical properties of porous GaN films of different porosities, focusing on the behaviors of the excitonic features in time-integrated and time-resolved photoluminescence. A substantial enhancement of both excitonic emission intensity and recombination rate, along with insignificant intensity weakening under temperature rise, is observed in the porous GaN films. These observations are in line with (i) the local concentration of electric field at GaN nanoparticles and pores due to the depolarization effect, (ii) the efficient light extraction from the nanoparticles. Besides, the porosification enlarges the surface of the air/semiconductor interface, which further promotes the extraction efficiency and suppresses non-radiative recombination channels. Our findings open a way to increasing the emission efficiency of nanophotonic devices based on porous GaN.
关键词： light extraction,exciton,porous GaN,photoluminescence,depolarization effect
更新于2025-09-10 09:29:36
-
Fabrication of GaOx Confinement Structure for InGaN Light Emitter Applications
摘要： An indium gallium nitride (InGaN) light-emitting diode (LED) with an embedded porous GaN reflector and a current confined aperture is presented in this study. Eight pairs of n+-GaN:Si/GaN in stacked structure are transformed into a conductive, porous GaN/GaN reflector through an electrochemical wet-etching process. Porous GaN layers surrounding the mesa region were transformed into insulating GaOx layers in a reflector structure through a lateral photoelectrochemical (PEC) oxidation process. The electroluminescence emission intensity was localized at the central mesa region by forming the insulating GaOx layers in a reflector structure as a current confinement aperture structure. The PEC-LED structure with a porous GaN reflector and a current-confined aperture surrounded by insulating GaOx layers has the potential for nitride-based resonance cavity light source applications.
关键词： insulating GaOx,current confinement aperture structure,porous GaN,InGaN
更新于2025-09-04 15:30:14