Chemical vapor deposition low pressure

Diamonds also occur in meteorites, probably as a result of high pressures produced dynamically by impact (10,11). The shock or explosive mode of synthesis is a viable process for fine diamond powders of both the cubic and hexagonal (lonsdaleite) polymorphs (12) naturally or otherwise. Some diamonds in space appear to have formed by processes more closely related to the low pressure chemical vapor deposition processes described later (see... 

Gaczi, P. J., and Reynolds, G. J., Identification of Reaction Products in the Low-Pressure Chemical Vapor Deposition of Molybdenum Silicide, J. Electrochem. Soc., 136(9) 2661-2666 (Sept. 1989)... 

Titanium(IV) guanidinato complexes, which are easily accessible by the standard synthetic routes (cf. Section III.B.2), have been studied as precursors to titanium carbonitride. Thin films of titanium carbonitride were obtained by low-pressure chemical vapor deposition of either [(Me3Si)2NC(NPE)2]TiCl(NMe2)2 or [Me2NC(NPE)2]2TiCl2 at 600 Most recent developments in this field... 

The low-pressure chemical vapor deposition of silicon nitride on silicon involves two gaseous reactants dichlorosilane and ammonia. The following reactions are believed to be important under typical conditions of P = 1 torr and T= 1000 1200 K ... 

In this sub-subsection, the Er doping of amorphous silicon is discussed. The problem of limited solubility of Er in crystalline silicon has been circumvented. However, the electrical properties of pure a-Si are poor compared to c-Si. Therefore, hydrogenated amorphous silicon is much more interesting. Besides, the possibility of depositing a-Si H directly on substrates, i.e., optical materials, would make integration possible. Both low-pressure chemical vapor deposition (LPCVD) [664] and PECVD [665, 666] have been used to make the a-Si H into which Er is implanted. In both methods oxygen is intentionally added to the material, to enhance the luminescence. 

Optimization of Low-Pressure Chemical Vapor Deposition Reactor for the... 

EXAMPLE 14.5 OPTIMIZATION OF LOW-PRESSURE CHEMICAL VAPOR DEPOSITION REACTOR FOR THE DEPOSITION OF THIN FILMS... 

A typical multiwafer hot-wall low-pressure chemical vapor deposition reactor. 

Low polarity plasticizers, 74 479 Low power package, 74 863 Low pressure catalytic processes, 20 151 Low pressure chemical vapor deposition (LPCVD), 5 807, 811-812 Low-pressure gas separation, spiral-wound membrane modules for, 75 823-824 Low pressure hollow-fiber membranes, 76 24-26... 

A schematic view of the cold cathode fabrication process is shown in Fig. 10.18. The cold cathode is fabricated by low pressure chemical vapor deposition (LPCVD) of 1.5 pm of non-doped polysilicon on a silicon wafer or a metallized glass substrate. The topmost micrometer of polysilicon is then anodized (10 mA cnT2, 30 s) in ethanoic HF under illumination. This results in a porous layer with inclusions of larger silicon crystallites, due to faster pore formation along grain boundaries. After anodization the porous layer is oxidized (700 °C, 60 min) and a semi-transparent (10 nm) gold film is deposited as a top electrode. 

In chemical vapor deposition (CVD) complex shaped surfaces can be coated with homogeneous layers, especially when carried out at low pressure (LPCVD, low pressure chemical vapor deposition) (review Ref. [410]). A gas reacts with the heated substrate surface to give a solid coating and gaseous by-products which have to be removed continously. Layer thicknesses created by chemical vapor deposition are usually in the order 5-10 pm.. In cases where it is necessary to keep the temperature low, a plasma can stimulate the surface reaction in plasma enhanced chemical vapor deposition (PECVD). 

Adem of Advanced Micro Devices, Inc. was granted a patent on the use of Raman spectroscopy to monitor the thickness, crystal grain size, and crystal orientation of polysilicon or other films as they are deposited on semiconductor wafers via low-pressure chemical vapor deposition (CVD).89 The spectra are acquired with a non-contact probe through a suitably transparent window in the loading door. A feedback scheme is discussed. When the thickness has achieved the targeted value, the deposition is stopped. If the crystal grain size or orientation is deemed unsuitable, the deposition temperature is adjusted accordingly. 

LPCVD Low-pressure chemical vapor deposition X Wavelength (nm)... 

The wafers were coated with silicon dioxide (400 nm thickness) and silicon nitride by low pressure chemical vapor deposition (LPCVD) alternately. The chips were fabricated by photolithography and etching. The catalyst (for the application Pt) was introduced as a wire (150 pm thickness), which was heated resistively for igniting the reaction. The ignition of the reaction occurred at 100 °C and complete conversion was achieved at a stochiometric ratio of the reacting species generating a thermal power of 72 W (Figure 2.28). 

Franz et al. [93] developed a palladium membrane micro reactor for hydrogen separation based on MEMS technology, which incorporated integrated devices for heating and temperature measurement. The reactor consisted of two channels separated by the membrane, which was composed of three layers. Two of them, which were made of silicon nitride introduced by low-pressure chemical vapor deposition (0.3 pm thick) and silicon oxide by temperature treatment (0.2 pm thick), served as perforated supports for the palladium membrane. Both layers were deposited on a silicon wafer and subsequently removed from one side completely... 

Characterization of low-pressure chemical vapor deposited and thermally grown silicon nitride films. J. Appl. Phys. 53(1 ) 404 (1982). 

Si02 Buffert hydrofluoric acid, RIE Dry etching, deep reactive ion etching DRIE Thermische thermal oxidation, low-pressure chemical vapor deposition Crystallographic and wet chemical etching of silicon... 

Si3N4 RIE Low-pressure chemical vapor deposition Crystallographic and wet chemical etching of silicon... 

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