A GaN-Based LED With Perpendicular Structure Fabricated on a ZnO Substrate by MOCVD

Abstract

A perpendicular InGaN/GaN multiple-quantumwells structure on ZnO substrate for blue light emitting diode (LED) was successfully fabricated by use of Metal-organic Chemical Vapor Deposition (MOCVD). During the growing process of GaN-based materials on ZnO substrates, the low-temperature-grown GaN buffer layer, inserted between ZnO substrate and undoped GaN layer, prevented the Zn and O from diffusing from ZnO substrate into the n-GaN layer. This thin GaN buffer layer, mainly as a insulating layer, was grown at relatively low temperature of 530 C. By using our method, an integrated LED with ZnO substrate can be fabricated with a crack-free GaN film on (0001) ZnO substrate by MOCVD using this method. The epilayer crystalline structure has been measured by atomic force microscopy (AFM), and the optical properties of the LED were also characterized by photoluminescence and Current-Voltage characteristic curve.Index Terms-GaN, metal-organic chemical vapor deposition (MOCVD), substrate, ZnO.

Compliant Micron-Sized Patterned InGaN Pseudo-Substrates Utilizing Porous GaN

“…The availability of a relaxed InGaN buffer layer with a lattice parameter closer to that of the QWs is hence highly desirable to obtain high efficiency long wavelength (>500 nm) III-N LEDs or lasers. Attempts have been made to fabricate as-grown relaxed InGaN buffers on substrates such as ZnO [11][12][13] and ScAlMgO 4 [14,15]; however, the very low growth temperatures required for deposition on ZnO and the high n-type conductivity of InGaN grown on ScAlMgO 4 substrates have made metal-organic chemical vapor deposition (MOCVD) growth efforts on these substrates very challenging. Alternately, partially relaxed engineered InGaN substrates have been explored [6] and relaxed InGaN buffer layers have been fabricated by molecular-beam epitaxy (MBE) and used as pseudo substrates for MOCVD growth [9,16,17].…”

Zn Electrodeposition on Single-Crystal GaN(0001) Surface: Nucleation and Growth Mechanism

“…On the other hand, gallium nitride-(GaN-) based materials, with a wide band gap, have recently attracted great attention because of their wide applications in advanced optoelectronic devices [18][19][20]. Besides physics applications, there is an increasing interest in electrochemistry field due to their unique physicochemical properties.…”

ScAlMgO4 as a promising substrate for InGaN-based long wavelength emitters: demonstration of far-red LEDs

“…Suppression methods include a low growth temperature, 16 Al 2 O 3 passivation, 17 and nitrogen carrier gas. 18 On the other hand, we have demonstrated that ScAlMgO 4 (0001) substrates are chemically stable at growth temperatures of GaN (∼1000 • C). 20 In addition, we have established the growth conditions of In y Ga 1−y N (y ∼ 0.17) templates on lattice-matched ScAlMgO 4 (0001) 20 and, demonstrated that In x Ga 1−x N/In y Ga 1−y N QWs on In y Ga 1−y N/ScAlMgO 4 templates emit in the red spectral range.…”

“…[9][10][11][12][13][14][15] However, In y Ga 1−y N thick layers are typically grown on foreign templates such as GaN on sapphire and involve numerous threading dislocations. One way to avoid the lattice mismatch between In y Ga 1−y N and the underlying template is to use a substrate lattice-matched to In y Ga 1−y N. Toward this end, ZnO [16][17][18] and ScAlMgO 4 [19][20][21][22][23][24][25][26] are attractive as their a-lattice parameters match those of In 0.18 Ga 0.82 N and In 0.17 Ga 0.83 N, respectively. However, for ZnO substrates, interfacial reactions during the growth of nitride semiconductors must be suppressed.…”