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Starting from the early 1990s, set off a worldwide high-brightness visible light-emitting diode (LED) boom, is the rapid development of solid-state lighting based on it. Because of the high brightness LED with double heterojunction structure, the material has a good lattice match, this material requirements for heterojunction LED system proposed strict limits. Ⅲ - Ⅴ nitride semiconductor material with excellent optical and electrical properties, chemical properties are very stable and can be used in high-temperature, pH, radiation environment, and the band gap, and therefore attractive to high-power electronic devices, has attracted the interest of many researchers at home and abroad. The most interesting Ⅲ - Ⅴ nitride AIN, GaN, InN and alloys thereof, through the control of their respective component, its band gap can be from InN, 0.7eV to GaN-3.4eV until the AlN 6.2eV continuous change, covering the entire visible region, and extends to the UV range, suitable for the preparation of a high-brightness LED. Of this paper is on legislation in this case, the first measurement method using optical fluorescence, luminescence properties of wide bandgap semiconductor quantum well, compare the two sets of InGaN / GaN grown on sapphire and GaN substrate, respectively the luminescent properties in the quantum well at room temperature, and then further analyze the growth of InGaN on the GaN substrate / GaN multi-quantum well under low temperature luminescence characteristics. Finally, by AFM, the variable power optical organic luminescent (PL) and the cathode fluorescent spectrum of experimental means (CL), 4 InGaN / GaN single quantum well light-emitting characteristics, in addition to the growth temperature, these four samples other growth conditions are the same. Obtained the following conclusions: 1. Under the same excitation power density, the GaN substrate, the growth of InGaN / GaN multi-quantum well light emitting strength was significantly higher than on a sapphire substrate, thus proving the extended defects to have a great impact on the efficiency of recombination . Compound dominant under any temperature high-power excitation conditions, a free carrier (or free excitons) of the tape edge, and the band edge of the composite strength versus temperature or decrease in the excitation power weakened; at room temperature the following small power bound exciton complexes localized impurity level introduced dominant excitation conditions, the composite strength with temperature or excitation power decreased monotonically increasing. Band edge composite blue shift in the larger increase in the temperature of the sample or the excitation power, local bound exciton recombination radiation peak wavelength and excitation power changes with the temperature of the sample did not change significantly. 4. The bandedge composite width at half maximum (FWHM) does not vary with temperature and the pump power, shackles of localized exciton recombination with the half width of peak excitation power increases. 5. InGaN system whether phase separation occurs the same temperature, while the lattice mismatch between GaN and InGaN also affects the InGaN epitaxial layer in the phase separation. 6 the sample grown at 670 ℃, InGaN occurs phase separation, to form a rich InN quantum dots.
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