Plasma assisted chemical vapor deposition

Chemical Vapor Deposition. Chemical vapor deposition (CVD) of siHcon dioxide from tetraethoxysilane assisted by the presence of oxygen and a plasma is an important technology for the deposition of pure and modified dielectrics for microelectronics (61). An alternative method for the deposition of siHcon dioxide utili2es di-/-butoxydiacetoxysilane (62). 

Wang HB, Meng GY, and Peng DK. Aerosol and plasma assisted chemical vapor deposition process for multi-component oxide La08Sr02MnO3 thin film. Thin Solid Films 2000 368 275-278. 

Two principal classes of diamond film deposition have been developed (I) PACVD (plasma-assisted chemical vapor deposition) and (2) IBED (ion-beam-enhanced deposition). 

Chemical vapor deposition. Chemical vapor deposition is mainly used to prepare thin films and coatings, and infrequently, supported particles.68,69 The films are formed by the chemical reaction of a gas phase species with the heated surface of a substrate. The process can be assisted by a reactive gas like NH3, a plasma,7a 72 ultraviolet73,74 or laser75 radiation. 

A large class of coordination compounds, metal chelates, is represented in relation to microwave treatment by a relatively small number of reported data, mainly p-diketonates. Thus, volatile copper) II) acetylacetonate was used for the preparation of copper thin films in Ar — H2 atmosphere at ambient temperature by microwave plasma-enhanced chemical vapor deposition (CVD) [735a]. The formed pure copper films with a resistance of 2 3 pS2 cm were deposited on Si substrates. It is noted that oxygen atoms were never detected in the deposited material since Cu — O intramolecular bonds are totally broken by microwave plasma-assisted decomposition of the copper complex. Another acetylacetonate, Zr(acac)4, was prepared from its hydrate Zr(acac)4 10H2O by microwave dehydration of the latter [726]. It is shown [704] that microwave treatment is an effective dehydration technique for various compounds and materials. Use of microwave irradiation in the synthesis of some transition metal phthalocyanines is reported in Sec. 5.1.1. Their relatives - porphyrins - were also obtained in this way [735b]. 

Sherman, A., Plasma-assisted chemical vapor deposition processes and... 

Mo-silicide film by plasma assisted chemical vapor deposition, in Proceedings of 23rd Symposium on Semiconductor and 1C Technology of Japan, 1982, p. 60. 

PACVD or PECVD plasma-assisted or plasma-enhanced chemical vapor deposition... 

Plasma-enhanced chemical vapor deposition (also known as plasma-assisted chemical vapor deposition) a CVD... 

Subsequent preliminary comparative studies of the behavior of an SiC based layer on Ta, Mo, Ti and steel substrates showed that better mechanical stability was obtained with a coating deposited on tantalum. This element was consequently considered to make PFCVD deposit/interlayer/steel stacks. Tantalum can be produced by physical vapor deposition (PVD), at variable thickness, with reproducible morphology. Note that preparation by chemical vapor deposition with or without plasma assistance (CVD or PECVD) is possible at low temperature but would require an optimization study in order to be compatible with the deposition conditions of the silicon carbide layer, the aim being to increase the mechanical stability. 

However, in recent times, there have been several reports on synthesis of the crystalline form of carbonitride. Zhang et al. " synthesized crystalline carbonitride films with large crystalline grains up to 10 pm (from SEM and XRD spectra) in size by RE plasma assisted hot filament chemical vapor deposition. Li. et al. claimed to have synthesized poly crystalline C3N4 films (from XRD data) at ambient temperature by RE diode sputtering. Erom Auger electron spectroscopy, the N/C ratio was computed to be 1.33 as required for C3N4 stoichiometry. 

The material deposition that occurs in the low-pressure electrical discharge has been discussed under various terminologies such as plasma polymerization (PP), plasma-enhanced chemical vapor deposition (PECVD), plasma-assisted chemical vapor deposition (PACVD), plasma chemical vapor deposition (PCVD), and so forth [1]. However, none of these terminologies seems to represent the phenomenon adequately. The plasma aspect in the low-pressure discharge is remote, although it plays a key role in creating the environment from which material deposition occurs to the extent that no chemical reaction occurs without the plasma. In this sense, PECVD and PACVD could be out of the context in many cases in which nothing happens without plasma. In such cases, PP or PCVD would describe the phenomenon better. If the substrate was not heated substantially above the ambient temperature, the use of PECVD or PACVD should be avoided. 

In order to find the domain of LCVD, it is necessary to compare various vacuum deposition processes chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma chemical vapor deposition (PCVD), plasma-assisted CVD (PACVD), plasma-enhanced CVD (PECVD), and plasma polymerization (PP). All of these terms refer to methods or processes that yield the deposition of materials in a thin-film form in vacuum. There is no clear definition for these terms that can be used to separate processes that are represented by these terminologies. All involve the starting material in vapor phase and the product in the solid state. 

---