In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly impro...In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly improved due to the catalytic effect of trimethyl-gallium (TMGa), but AlN crystal structure and composition are not affected. When the proportion of TMGa in gas phase was low, crystal quality of AlN can be improved and three-dimensional growth mode of AlN was enhanced with the increase of Ga source. When the proportion of TMGa in gas phase was high, two-dimensional growth mode of AlN was presented, with the increase of Ga source results in the deterioration of AlN crystal quality. Finally, employing a two-step growth approach, involving the initial growth of Ga-free AlN nucleation layer followed by Ga-assisted AlN growth, high quality of AlN film with flat surface was obtained and the full width at half maximum (FWHM) values of 415 nm AlN (002) and (102) planes were 465 and 597 arcsec.展开更多
AlN was used as a host material and doped with Eu grown on Si substrate by pulsed laser deposition (PLD) with low substrate temperature. The X-ray diffraction (XRD) data revealed the orientation and the composition of...AlN was used as a host material and doped with Eu grown on Si substrate by pulsed laser deposition (PLD) with low substrate temperature. The X-ray diffraction (XRD) data revealed the orientation and the composition of the thin film. The surface morphology was studied by scanning electron microscope (SEM). While raising the annealing temperatures from 300˚C to 900˚C, the emission was observed from AlN: Eu under excitation of 260 nm excitation. The photoluminescence (PL) was integrated over the visible light wavelength shifted from the blue to the red zone in the CIE 1931 chromaticity coordinates. The luminescence color coordination of AlN: Eu depending on the annealing temperatures guides the further study of Eu-doped nitrides manufacturing on white light emitting diode (LED) and full color LED devices.展开更多
Cubic AlN thin films were obtained on quartz substrate by pulse laser deposition in a nitrogen reactive atmosphere.A Nd-YAG laser with a wavelength of 1064 nm was used as the laser source.In order to study the influen...Cubic AlN thin films were obtained on quartz substrate by pulse laser deposition in a nitrogen reactive atmosphere.A Nd-YAG laser with a wavelength of 1064 nm was used as the laser source.In order to study the influence of the process parameters on the deposited AlN film,the experiments were performed at various technique parameters of laser energy density from 70 to 260 J/cm^2,substrate temperature from room temperature to 800℃and nitrogen pressure from 0.1 to 50 Pa.X-ray diffraction,scanning electron microscopy and X-ray photoelectron spectroscopy were applied to characterize the structure and surface morphology of the deposited AlN films.It was found that the structure of AlN films deposited in a vacuum is rocksalt under the condition of substrate temperature600-800 ℃,nitrogen pressure 10-0.1 Pa and a moderate laser energy density（190 J/cm^2）.The high quality AlN film exhibited good optical property.展开更多
基金supported by the Key Research and Development Program of Jilin Provincial Department of Science and Technology (No. 20210201031GX)Innovation capacity building project of Jilin Province (No. 2023C031-2)The Key Research and Development Program of Jiangsu Province (No. BE2022057-1)。
文摘In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly improved due to the catalytic effect of trimethyl-gallium (TMGa), but AlN crystal structure and composition are not affected. When the proportion of TMGa in gas phase was low, crystal quality of AlN can be improved and three-dimensional growth mode of AlN was enhanced with the increase of Ga source. When the proportion of TMGa in gas phase was high, two-dimensional growth mode of AlN was presented, with the increase of Ga source results in the deterioration of AlN crystal quality. Finally, employing a two-step growth approach, involving the initial growth of Ga-free AlN nucleation layer followed by Ga-assisted AlN growth, high quality of AlN film with flat surface was obtained and the full width at half maximum (FWHM) values of 415 nm AlN (002) and (102) planes were 465 and 597 arcsec.
文摘AlN was used as a host material and doped with Eu grown on Si substrate by pulsed laser deposition (PLD) with low substrate temperature. The X-ray diffraction (XRD) data revealed the orientation and the composition of the thin film. The surface morphology was studied by scanning electron microscope (SEM). While raising the annealing temperatures from 300˚C to 900˚C, the emission was observed from AlN: Eu under excitation of 260 nm excitation. The photoluminescence (PL) was integrated over the visible light wavelength shifted from the blue to the red zone in the CIE 1931 chromaticity coordinates. The luminescence color coordination of AlN: Eu depending on the annealing temperatures guides the further study of Eu-doped nitrides manufacturing on white light emitting diode (LED) and full color LED devices.
基金supported by the Yunnan Provincial Natural of Science Foundation of China(No.KKSY201251089)
文摘Cubic AlN thin films were obtained on quartz substrate by pulse laser deposition in a nitrogen reactive atmosphere.A Nd-YAG laser with a wavelength of 1064 nm was used as the laser source.In order to study the influence of the process parameters on the deposited AlN film,the experiments were performed at various technique parameters of laser energy density from 70 to 260 J/cm^2,substrate temperature from room temperature to 800℃and nitrogen pressure from 0.1 to 50 Pa.X-ray diffraction,scanning electron microscopy and X-ray photoelectron spectroscopy were applied to characterize the structure and surface morphology of the deposited AlN films.It was found that the structure of AlN films deposited in a vacuum is rocksalt under the condition of substrate temperature600-800 ℃,nitrogen pressure 10-0.1 Pa and a moderate laser energy density（190 J/cm^2）.The high quality AlN film exhibited good optical property.
基金Project(21271188)supported by the National Natural Science Foundation of ChinaProject(2012M521541)supported by the China Postdoctoral Science Foundation+2 种基金Project(2012QNZT002)supported by the Fundamental Research Funds for the Central South Universities,ChinaProject(20110933K)supported by the State Key Laboratory of Powder Metallurgy,ChinaProject(CSU2012024)supported by the Open-End Fund for Valuable and Precision Instruments of Central South University,China
