Applications of MOCVD

Table 4.3. is a summary of the major applications of MOCVD. More details are found in Chs. 13-16.Pi... 

The many possible combinations of II-V and II-VI compounds allow the tailoring of electronic and opto-electronic properties to suit specific applications. Of particular importance is the control of the stoichiometry of the element involved. This is achieved by the proper handling of the MOCVD reactions. Being able to tailor the bandgap imparts great flexibility in the design of transistors and optoelectronic devices. 

LED materials include gallium arsenic phosphide, gallium aluminum arsenide, gallium phosphide, gallium indium phosphide, and gallium aluminum phosphide. The preferred deposition process is MOCVD, which permits very exacting control of the epitaxial growth and purity. Typical applications of LED s are watches, clocks, scales, calculators, computers, optical transmission devices, and many others. 

M. Razeghi, LP-MOCVD Growth, Characterization, and Application of InP Material T.A. Kennedy and P.J. Lin-Chung, Stoichiometric Defects in InP... 

Cyclopentadienyl compounds (i.e. metallocenes) (Fig. 5), which have at least one direct metal-carbon bond to the C5H5 ligand, were first synthesised in the 1950s [79,80]. Since then, reactions of cyclopentadienyl reagents have been applied for almost every element [123]. The main application of metallocenes is their use as catalysts in the polymerisation of olefins by Ziegler-Natta polymerisation processes. As many metallocene compounds are volatile and thermally stable, they are also suitable for use as precursors in MOCVD [124-127]. Although cyclopentadienyl compounds have attracted considerable interest as precursors in CVD depositions they are sometimes too reactive [128]. However, high reactivity and thermal stability make cy-... 

This article focuses primarily on the properties of the most extensively studied III—V and II—VI compound semiconductors and is presented in five sections (/) a brief summary of the physical (mechanical and electrical) properties of the zincblende cubic semiconductors (2) a description of the metal organic chemical vapor deposition (MOCVD) process. MOCVD is the preferred technology for the commercial growth of most heteroepitaxial semiconductor material (J) the physics and (4) applications of electronic and photonic devices and (3) the fabrication process technology in use to create both electronic and photonic devices and circuits. 

Concerning the application of gallium alkoxides, one can mention the selective catalytic activity of Ga(OPh)3in the condensation reactions of isobutene with phenols. In(OR)3 is used for the preparation of solutions for production of ln203 and In2Oj-related conduction films [1618] and also in the synthesis of volatile precursors for MOCVD deposition of In2Oj [830]. 

An important new application for MOCVD is the deposition of pure metal films for semiconductor integrated circuit applications. Important metals deposited by MOCVD include Al, Cu, CuAl alloys, and W films using precursors listed in Table I. It is expected that this application area for MOCVD will expand rapidly in the next few years as the demand increases for high-density metal interconnects for Si integrated circuit technology. High-purity Al metal films have also been grown by MOCVD. 

The most important applications of organolanthanides are as Ziegler-Nutta catalysts in polymerization of olefins and as reagents in stoichiometric organic synthesis. Organolan-thanide compounds are also useful as volatile precursors for MOCVD applications in the... 

In the last years transition metal-silyl complexes have received special attention for several reasons [1, 2], On the one hand, they are assumed to be important intermediates in catalytic processes [2] (transition metal-catalyzed hydrosilylation reaction, dehydrogenative coupling of silanes to polysilanes, etc.), on the other metal-substituted silanes show special properties, which can be tuned systematically by judicious choice of the metal and its ligands [3] Furthermore, silylenes (silanediyls) are stabilized by unsaturated transition metal fragments leading to metal-silicon double-bonds [4]. In the light of a possible application in MOCVD processes some of these complexes are of interest as potential single-source precursors for the manufacture of thin silicide films [5]. 

Although metal alkoxides proved to be excellent precursors for the preparation of ceramics by the sol-gel process, their applications in the MOCVD technique are not as widespread, in spite of the attractive features of their volatility and tendency to decompose to the metal oxides. Both of these desirable prerequisites appear to be enhanced, as discussed earlier, by choosing more ramified alkoxide groups. Despite these attractive features, the MOCVD applications of metal alkoxides appear to be limited by (a) their commercial nonavailability, (b) handling difficulties arising from their ready hydrolyzability, and (c) the lack of a clear understanding of their decomposition pathways, which could lead to improvement(s) in the purity of the deposited material. 

Volume 9 is concerned with actual and potential applications of metal coordination complexes. Major developments since the 1980s in the uses of coordination compounds have occurred in catalysis and medicine. There have been important developments of coordination chemistry in the technology of dyes and optical materials, for solar energy harvesting, for hydrometallurgical extraction, and in providing MOCVD precursors for new electronic materials. As mentioned above, the last volume in the series contains the indexes. 

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. 

The rapidly advancing applications of metal alkoxides for synthesis of ceramic materials by sol-gel/MOCVD (metallo-organic chemical vapour deposition) processes (Chapter 7) have more recently given a new impetus to intensive investigations on synthetic, reactivity (including hydrolytic), structural, and mass-spectroscopic aspects of oxo-alkoxide species. ... 

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