CVD metal-organic

The transparent top contact is deposited last of all, which imposes restrictions on the process temperature. Thermally evaporated ITO and ZnO deposited by metal-organic CVD (MOCVD) are most suitable. At a typical thickness of 70 nm the ITO serves as a good antireflection coating as well. Due to the somewhat high sheet resistance, a metal (Ag) grid is necessary to reduce the series resistance [11]. 

Films at NASA GRC were deposited using homemade spray or aerosol-assisted chemical vapor deposition (AACVD) reactors to exploit the lower deposition temperature enabled by the simpler decomposition chemistry for the SSPs.6 9 AACVD is a simple and inexpensive process that offers the advantage of a uniform, large-area deposition, just like metal organic CVD (MOCVD), while also offering the low-temperature solution reservoir typical of spray pyrolysis methods. 

Vahlas C, Juarez F, et al (2002) Fluidization, spouting, and metal-organic CVD of platinum group metals on powders. Chemical Vapor Deposition 8(4), 127-144... 

Watson IM (1997) Metal-organic CVD of the high-T-c superconductor YBa2Cu307-delta. Chemical Vapor Deposition 3(1), 9-26... 

Before the metal-organic CVD (MOCVD) process of the BST film is discussed, the reasons for using the CVD process, despite its difficulties should be described. The storage node size of the capacitors in the current state-of-the-art DRAMs is about 0.15 x 0.35 x 1.0 pm with minimum spacing of about 0.15 pm between the nodes when the dielectric layer is a SiO/SijN bi-layer or Ta O, and the electrode materials are poly-Si. Here 1 pm is the height of the nodes. Even smaller lateral dimensions are expected when DRAMs use a BST thin film as the capacitor dielectric layer. Even though the BST films have a much smaller t value, which... 

Tremendous fundamental research especially in the CVD technologies and precursor synthesis extends the applicability to some new area. These technologies include metal-organic CVD (MOCVD), plasma-enhanced CVD, photo CVD and laser induced CVD etc. The advancement of the synthesis technology provides new precursors to deposit a variety of materials with high purity. 

In the first chapter of this book, an overview of CVD techniques has been given, and more detailed descriptions can be found in several textbooks [9, 10]. Many different CVD reactors have been used for the deposition of conducting films, i.e., thermal, UV-enhanced CVD (UVCVD), laser-assisted CVD (LACVD), plasma-enhanced CVD (PECVD) and metal-organic CVD (MOCVD). In addition, two techniques were included, which are not typically part of CVD, chemical transport and spray pyrolysis. 

The main deposition methods of NS-Ti02 onto stainless steels are cathodic arc deposition [532], electrophoretic deposition [533], anodic spark deposition (ASD) [534], the sol-gel method [535, 536], atmospheric pressure metal organic CVD (AP-MOCVD) [537, 538] and radio frequency (RF) magnetron sputtering [539]. Preparation methods and applications of NS-Ti02 thin films on stainless steel have been summarized in Table 15. 

Atmospheric pressnre metal organic CVD Photocatal34ic degradation of stearic acid [538]... 

Chemical vapor deposition (CVD). In CVD, the material s components come from the decomposition of one or more volatile chemical precursors that decompose and/or react on the substrate. Depending on deposition conditions (temperature and pressure) and the precursor nature, different terminologies are used to define CVD processes. Eor example, MOCVD is metal organic CVD, LPCVD is low-pressure CVD, ALCVD is atomic layer CVD, HWCVD is hotwire CVD, and PECVD is plasma-enhanced CVD. These processes can lead to single crystal, amorphous, or polycrystaUine films. 

MOCVD PECVD Metal-organic CVD Plasma- enhanced CVD RE Reactive evaporation... 

The conventional CVD method uses thermal energy to activate chemical reactimis, which is commonly known as thermally activated CVD (TACVD). CVD reactions can be initiated by using different energy sources. Plasma and light energy are currently being used to activate the chemical reactions. Other types of CVD include atomic layer epitaxy, metal-organic CVD, flame-assisted CVD, and electrochemical vapor deposition. They are briefly discussed herewith [1,5]. 

Until 1995, micrometer scale whiskers of the lll-IV semiconductors have been grown only by metal-catalyzed or metal-organic CVD processes at relatively high temperatures, e.g., SiSOO C. Lack of useful crystallization mechanisms for highly covalent non-molecular solids has so far prevented their growth at lower process temperatures. A recent breakthrough [18]... 

The process is based on a novel reaction using the otherwise well-studied metal-organic CVD process under conditions which support low temperature growth, i.e., catalysis of the reaction by protic hydrocarbon solvents and catalysis of whisker growth by metallic indium flux particles (droplets). The flux particles, in turn were produced in-situ during the reaction as a partial decomposition product of t-BusIn (Equation 13). 

Hydrogen reduction, chemical transport, hydrogen decomposition, metal organic CVD, plasma CVD... 

Figure 12.4 A schematic of the pyrolysis processes taking place across the stagnant layer in the gas phase of a cold-wall metal-organic CVD reactor. In a hot-wall reactor the gas may pyrolyze outside of the stagnant layer. Other species present may include completely pyrolyzed TMG resulting in elemental Ga in the gas and pyrolysis products including hydrogen such as Ga(CH3)H2. Figure based on data in Ingle et al. [1]...

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