Nonpolar light emitting diode made by m-plane n-ZnO/p-GaN heterostructure

Abstract

Nonpolar (100) m-plane n-ZnO/p-GaN light-emitting-diodes (LEDs) were grown by chemical vapor deposition on p-GaN templates which was grown by metalorganic chemical vapor deposition on LiAlO 2 (100) substrate. Direct current (DC) electroluminescence (EL) measurements yielded a peak at 458nm. The EL peak position was independent of drive current and a full width of half maximum (FWHM) of 21.8 nm was realized at 20mA. The current-voltage characteristics of these diodes showed a forward voltage (V f) of 6V with a series resistance of 2.2 × 10 5 Ω.

Growth of c-plane ZnO on γ-LiAlO2 (100) substrate with a GaN buffer layer by plasma assisted molecular beam epitaxy

“…Accordingly, the same value (0.14 • ) of the FWHM of the (1010) ZnO rocking curve was obtained for the m-ZnO epilayer deposited on (1 0 0) LAO, without a GaN buffer, by chemical vapor deposition in another study [11]. The higher defects density of the present c-plane ZnO may result in a broad PL peak of a FWHM of twice as large as the m-plane one [11,20].…”

“…ZnO epilayer oriented in the nonpolar direction (i.e., [1010]) has also been deposited on GaN buffered LAO (1 0 0) substrate by chemical vapor deposition [20]. The FWHM of the (1010) rocking curve was 0.14 • which is lower than the present value for the (0 0 0 2) rocking curve.…”

“…However, the reported FWHM values of the (0 0 0 2) rocking curve were larger than 1.3 • , implying the inferior crystalline quality of c-plane ZnO on LAO (1 0 0) substrate. Gallium nitride (GaN) is considered as a promising buffer layer for high quality ZnO epitaxy due to the same crystal structure type and the low lattice mismatch [16][17][18][19][20].…”

Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters

“…The Ag-doped ZnO is an alternative to white light LEDs based on InGaN [24][25][26][27], which became already a commercial product. Although the quantum yield of InGaN based LEDs approaches a value of up to 70% [24][25][26], but these light sources have unidirectional emission and still are expensive.…”

Selective patterned growth of ZnO nanowires/nanosheets and their photoluminescence properties

“…ZnO is an attractive semiconductor oxide with direct band-gap of 3.3 eV and large exciton binding energy of 60 meV. Many promising applications for ZnO have been proposed as UV photodetectors [1,2], sensors [3][4][5], photocatalytic materials [6][7][8], piezoelectric devices [9,10], and light-emitting devices [11,12]. In particular, low-dimensional ZnO nanoparticles have received considerable attentions due to their large surface-to-volume ratios.…”