Chemistry of inorganic compounds – Nitrogen or compound thereof – Binary compound
Patent
1995-08-28
1999-09-07
Bos, Steven
Chemistry of inorganic compounds
Nitrogen or compound thereof
Binary compound
423440, 423592, 423625, 204164, 422907, C01B 2100, C01B 3100, C01B 1300
Patent
active
059483792
DESCRIPTION:
BRIEF SUMMARY
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the U.S. national phase of PCT application PCT/DE94/00047 filed Jan. 22, 1994 with a claim to the priority of German application P 43 03 492.6 itself filed Feb. 6, 1993.
FIELD OF THE INVENTION
The invention relates to an apparatus for depositing solid materials with a plasma-chemical process from gaseous metal chlorides, hydrogen, oxygen, and/or nitrogen and/or a carbon-containing gas in a reactive mixture ionized by glow discharge, using a reaction vessel into which a gas input opens with a plurality of outlet apertures. The invention further relates to a method of depositing solid materials by using a glow-discharge activated CVD method by means of metal chlorides, hydrogen, oxygen, and/or nitrogen and/or a carbon-containing gas in a reactive mixture that is fed at high speed into a reaction chamber in which a constant working pressure is maintained.
BACKGROUND OF THE INVENTION
The so-called CVD method where a solid material is formed from gaseous reaction materials has been normally used for many years to separate TiC or TiN by introducing titanium chloride and hydrogen and methane or nitrogen as carbon or nitrogen supply. It is similarly known to use aluminum chloride and carbon dioxide as donators for separating out Al.sub.2 O.sub.3. The process parameters in a CVD method can be set so that no solid adhering deposit, only loose deposits (powder) are formed. The CVD method is carried out in heated reaction chambers partially under subatmospheric pressure. According to the concentration of the reaction partners in the vehicle gas as well as the temperature and flow velocity there are various deposition rates, compositions, and structures or textures of the layer.
It is particularly important to the plasma CVD method that one can operate at low temperatures. If the reaction gas is mixed in a low-pressure glow discharge with an unbalanced plasma, the charge carriers in the gas are accelerated by the existing electrical field. The free travel between two impacts is dependent on the particle density or the pressure. If the particle energy reaches the applied voltage, molecules or atoms can be excited to the point of disassociation or ionization making possible chemical reactions that could otherwise only take place at higher temperatures. In principle low-pressure plasmas are created by applying a constant direct-current voltage or a pulsed direct-current voltage to a cathode-polarized workpiece as for example described in German 3,841,731.
In U.S. Pat. No. 4,909,183 at first an evacuatable chamber is described in whose center is arranged a rotatable holder for the coating substrate. The substrate itself is surrounded by a cylindrical cathodic electrode which is connected with a high-frequency voltage source. The substrate serves as anode so that when voltage is applied to the cathode a low-pressure plasma is created. Disadvantageously the material deposits on the cathode with the gas outlet apertures so that after a short time the gas flow is accurately eliminated.
U.S. Pat. No. 4,991,542 describes a reaction chamber in whose center is arranged a substrate body connected with a high-frequency sources and to whose sides there are diametrally opposite electrodes also serving as gas infeeds. The electrodes are formed as funnels and have multiple gas outlet apertures directed like a shower toward the substrate. Instead of connecting the voltage source with the substrate or with the substrate holder, it is connected with mesh electrodes which are arranged on both sides between the substrate and the gas-shower electrodes.
In European 0,257,620 a method and apparatus for forming a layer by a plasma-chemical process is described where at least three electrodes, preferably connected to a high-frequency source, are used which are arranged in a reaction chamber that is evacuatable and chargeable with gas. The substrate surface should extend perfectly or nearly perfectly parallel to an electrical field formed between the electrodes. The gas necessary t
REFERENCES:
patent: 2837654 (1958-06-01), Berghaus et al.
patent: 3642442 (1972-02-01), Hoekje et al.
patent: 4113584 (1978-09-01), Johnson
patent: 4333814 (1982-06-01), Kuyel
patent: 4450787 (1984-05-01), Weakliem et al.
patent: 4769064 (1988-09-01), Buss et al.
patent: 4806333 (1989-02-01), Egerton et al.
patent: 4909183 (1990-03-01), Kamiya et al.
patent: 5021134 (1991-06-01), Blackburn et al.
patent: 5173328 (1992-12-01), Reiter et al.
Konig Udo
Tabersky Ralf
Bos Steven
Dubno Herbert
Wilford Andrew
LandOfFree
Plasma-chemical deposition of very fine particles does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Plasma-chemical deposition of very fine particles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Plasma-chemical deposition of very fine particles will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1801915