GaN blue light emitting diodes prepared by metalorganic chemical vapor deposition

Abstract

The epitaxial layers of GaN have been grown on (0001)-oriented sapphire substrates using metalorganic chemical vapor deposition. The layers with good quality and relatively smooth surface morphology were obtained by enforcing growth in H2 after adherence of nuclei to the substrates in N2 atmosphere. Using this technique, GaN light emitting diodes with metal-insulating n-type structure were fabricated. Two kinds of blue electroluminescence were observed at room temperature with exciting voltage of 4–8 V with emission wavelength of 430 and 488 nm. The external efficiency is about 0.005%.

Two local vibrational modes related to hydrogen in GaN

“…[1][2][3][4] In Si and GaAs the effects of hydrogen have been extensively studied. The local vibrational modes ͑LVM͒ of hydrogen bound to a large variety of dopants have been identified.…”

In situ gravimetric monitoring of surface reactions between sapphire and NH3

“…Sapphire is widely used as a substrate for the growth of AlN by vapor-phase epitaxy (VPE), including metalorganic VPE (MOVPE) and halogen-transport VPE (HVPE), due to its good thermal and chemical stability [1,2]. The growth of high-quality AlN requires a high growth temperature over 1200 1C.…”

In situ Gravimetric Monitoring of Decomposition Rate on Surface of (1012) R-Plane Sapphire for High-Temperature Growth of Nonpolar AlN

“…The growth of Al-containing nitrides by vapor-phase epitaxy (VPE), including metalorganic VPE (MOVPE) and halogen-transport VPE (HVPE), generally uses sapphire as a substrate because of its good thermal and chemical stability. 1,2) The optimum temperature for achieving high-quality AlN by VPE is above 1200 C. 3) Recently, several groups have been trying to grow highquality AlN layers on (0001) C-plane sapphire substrates at temperatures above 1200 C by VPE. [4][5][6][7] However, little is known about the stability of C-plane sapphire substrates at such high temperatures.…”