| GaN is considered one of the typical representatives of the third generationsemiconductors for its eminent properties and great applications. In recent years, therealms related with it have attracted more and more researchers'attention.GaN is a kind of semiconductor with wide (3.39 ev) and direct band-gap, whichmakes it entrenched itself in the application of short-wave photoelectric devices. GaNand its related alloys, who have the continuous and adjustable band-gaps from 1.6 ev(InN) to 6.2 ev (AlN), are eligible materials to obtain the luminescence of visible lightand ultraviolet light and produce short wave laser devices (LDs).GaN-based diodes ofnear ultraviolet, blue and green light have been manufactured for commercial purpose.And the investigation to GaN-based LDs and detectors are now in the ascendant. Forits wider band gap, GaN LDs have shorter wavelength, which can enhance the storagedensity of LD memory greatly. Moreover, worth the whistle, GaN-based white lightLEDs, with lower energy consumption, higher efficiency, longer lifetime and lowerprice, are truly luminescence resources, which are expected to substitute traditionalincandescent lamp and take the primary role in future lighting. That will changed ourlife greatly!GaN, with low expansion coefficient and high conductive factor, also has goodstability at high temperature and low noise in microwave band. Therefore it is aproper material to produce high-power devices and microwave devices. And it is themost important substitutional material of traditional semiconductors in some severecircumstances.One-dimensional (1D) GaN nanostructures, with many novel properties, have anapplied potential in 1 D systems. The investigations of 1D nanostructure of GaN madeup the most active researching area in the world.The researching to GaN has a history of tens of years. In this area, the biggestproblems plaguing researchers is that GaN bulk single-crystalline material is notavailable. Consequently there is no proper homogeneous substrate for GaN's epitaxy.In view of silicon's well-developed technology and low price, it can serve as theheterogeneous substrate for GaN. Unfortunately, silicon has its defects such as highlattice mismatch and bad wetness with GaN. Although MOCVD and MBE technologyand the using of buffer layers enhanced the silicon-based films'quality, they broughtabout a new disadvantage ——high expenditure. In order to overcome these defects,we used radio frequency magnetron sputtering and subsequently ammoniating (thinfilms'reacting with ammonia)methods, with SiC layers deposited on silicon substratewith sputtering as intermediate layers, to prepare GaN films. It can be testified by themeasurement results that intermediate layers can enhance GaN's quality. In addition, single-crystalline 1D hexagonal nanostructures (mostlynanowires-NWs) were obtained with the same technology but different conditions.These nanostruceures were tested and indexed. Simultaneously, through analyzingtesting results, the changing rules along the ammoniating duration were revealed. The main contents of this paper is as follows: 1. Ga2O3/SiC films were deposited with radio frequency magnetron sputtering; subsequently they were ammoniated and turned into GaN films. SiC was sputtered onto Si (111) earlier than Ga2O3 and served as intermediate layer. We found that, the ultimate films are continuous polycrystalline hexagonal GaN; the films with intermediate layers have better quality than those without intermediate layers; the quality of the obtained films are influenced by the ammoniating temperature, and 950 ℃is the optimum temperature; 15 nm is the best intermediate thickness for GaN's epitaxy. 2. Changing of substrates causes different results. When we used crystal and sapphire substrates, we got films with mew morphology. Since porous silicon (PS) is a kind of luminescence material, some new luminescence properties of GaN on PS are hope to be realized. We found that the films obtained on PS with the previously depicted method are composed of many incontinuous GaN grains,...
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