IF GaN magnetron sputtering

　　Title: IF GaN magnetron sputtering
　　Author: Yin Mingli
　　Degree-granting units: Wuhan University
　　Keywords: nitrogen Jia;; aluminum nitride;; magnetron sputtering;; Photoluminescence;; IF;; ion source
　　Abstract:
　　In the wide band gap semiconductors, Ⅲ-nitride InN, GaN and AlN for direct bandgap semiconductors, band gap, respectively 0.7eV, 3.4eV and 6.2eV, their ternary alloys also have a direct band gap characteristics , can be prepared from a variety of 0.7eV-6.2eV band gap semiconductor material, its wavelength from infrared to ultraviolet covering the full range of visible light, enabling red, yellow, and blue with solid all-optical display. Growth of GaN and AlN thin film methods are mainly metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy outside (MBE), hydride vapor phase epitaxy (HVPE), pulsed laser deposition (PLD) and a variety of preparation methods of evaporation and sputtering . Sapphire (α-Al2O3) or silicon carbide ((SiC) is a commonly used preparation of GaN and AlN thin film substrate material, these substrate materials can be prepared by high-quality heteroepitaxial GaN and AlN films.
　　However, these substrates by the price and size and other factors, an increase of GaN and AlN materials and devices in the manufacturing cost, in Magnetic lifter silicon (Si) substrates and GaN films prepared optoelectronics and microelectronics devices, can be large rate to reduce costs, Si is very important to the growth of nitride substrate material. Glass substrate solar cells is important, not only low cost but also get a large area, if the glass substrates in high-quality GaN films will be of great significance, GaN widespread use will no longer be a dream. Widely used in the photovoltaic industry, the ordinary glass melting temperature is only 500-600 ℃, while the use of traditional methods of growth temperature is generally in 600-1000 ℃, therefore, in GaN films grown on glass need to find a low-temperature growth technology.
　　In this paper, self-designed frequency twin magnetron sputtering system in the Si (111) and quartz glass substrates were fabricated on GaN films. In the original system and added to the anode layer ion assisted deposition source AlN films. X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), 325nm He-Cd laser and micro-Raman spectrometer and a series of tests to detect the film means to study the different deposition pressure, substrate bias, Ar/N2 ratio target - substrate distance and deposition time of preparation conditions on the film structural properties, electrical properties and optical properties such as impact, and to explore the growth mechanism of the film and light-emitting mechanism. The results achieved are as follows:
　　1 twin with own design frequency magnetron sputtering system in a variety of process conditions in the growth of GaN and AlN films. This system has a pair of twin sputtering target, and the frequency power supply connected to two output electrodes. Sputtering http://www.999magnet.com/ process, the two alternately as a cathode sputtering target, can significantly reduce or even avoid the nitride formation in the target surface, while enhancing the sputtered atoms on a substrate with a sufficient response to reactive gases, deposition rate increased significantly , GaN thin film deposition rate peaked at 5.3μm / h.
　　2, respectively, in Si (111) substrate and quartz glass substrates on the growth of the GaN film and Si (111) AlN films grown on substrates. Systematic study of the various process parameters (pressure, bias, N2/Ar ratio, sputtering and sputtering from the time) for GaN and AlN film properties. Of GaN and AlN thin films are polycrystalline, hexagonal wurtzite structure with a C-axis preferred orientation. GaN films by cross-sectional analysis shows that, GaN growth was columnar structure. The best quality GaN film half-width only -721 arc seconds, and the best quality of AlN thin films are the only even half-width -612 arc seconds.
　　3 MF twin magnetron sputtering in the system by adding an anode layer ion source for deposition of preferred orientation is good, smooth surface and dense structure of the AlN films. Using the anode layer ion source assisted deposition of AlN thin films than the anode layer ion source without the use of assisted deposition of AlN thin films in the quality of the structure, density, smoothness, and the deposition rate and so have a clear advantage, with the anode layer ion source assisted deposition the smoothest surface roughness of AlN films only 0.13nm.
　　4 to obtain the light absorption and photoluminescence spectra, and different process parameters of GaN and AlN film growth mechanism and conducted a preliminary study of luminescent properties.
　　Degree Year: 2010