Optical Properties of Staggered InGaN/InGaN/GaN Quantum-Well Structures with Ga- and N-Faces

Abstract

Optical properties of staggered InGaN/InGaN/GaN quantum-well (QW) light-emitting diodes with Ga-and N-faces were investigated using the multiband effective mass theory. The staggered QW structure shows that the carrier density dependence of the transition wavelength is largely reduced compared to the conventional QW structure. On the other hand, the heavy-hole effective mass around the topmost valence band is almost unaffected by the polarity. The N-face staggered InGaN/InGaN/GaN QW structure has a greater spontaneous emission peak than the Gaface staggered InGaN/InGaN/GaN QW structure because the former has a larger matrix element than the latter. We expect the N-face staggered InGaN/InGaN/GaN QW structure to have improved characteristics compared with the Ga-face staggered InGaN/InGaN/GaN QW structure.

Investigation of nanopatterned c-plane sapphire Substrates for Growths of polar and nonpolar GaN epilayers

“…Such QWs often suffer electric field induced by the discontinuities in spontaneous and piezoelectric polarization at heterointerfaces due to the quantum-confined Stark effect (QCSE) [1]. Some approaches were proposed for increasing the internal quantum efficiency (IQE) of GaN-based LEDs, including the increment of radiative recombination rate in QWs [2][3][4][5] and the improvement of crystalline quality of GaN epilayer, viz. the defect reduction.…”

“…the defect reduction. The former methods can be used the InGaN waveguiding layers [2] and the staggered InGaN QWs with large electron-hole wavefunction overlap [3][4][5]. Though the methods can be used to improve the IQE of GaN-based LEDs, the QCSE is inevitable.…”

Correlation between defect properties and internal quantum efficiency in blue-emitting InGaN based light emitting diodes

“…In addition to the defect issue, the IQE and output power for InGaN QW LEDs are also affected by charge separation issue attributed to the existence of electrostatic field in the polar QW. Several approaches by using c-plane InGaN QW with large overlap design [19][20][21] and non-=semi-polar InGaN QW (Refs. 22 and 23) have been employed for reducing the charge separation issues in nitride LEDs and lasers.…”

Metalorganic vapor phase epitaxy and characterizations of nearly-lattice-matched AlInN alloys on GaN/sapphire templates and free-standing GaN substrates

“…Recently, III-nitride semiconductors have been widely employed for energy-efficiency device technologies, including light-emitting diodes (LEDs) for solid state lighting [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19], visible diode lasers for both display and biosensing [20][21][22][23][24][25][26], photovoltaics and solar energy conversion [27][28][29], and thermoelectric heat conversion and active cooling materials [30][31][32][33][34][35][36][37][38][39]. In designing structures in nitride-based devices for photonics and electronics applications, the most-widely studied heterostructures have been primarily limited to AlGaN/GaN and InGaN/GaN configurations.…”