CS252859B1 - Method of tungsten thin layers formation on conductive substrate - Google Patents

Abstract

The solution determines the method of preparing themes layers of tungsten formed in the bag in plasma. Tungsten forms layers on the surface electrically conductive substrate by acting plasma generated by inert gas and vapor Tungsten hexalkarbonyl, t pressure from 10-3 Pa to 102 Pa; heat the substrate to 550 ‘O.

Description

The invention relates to a method for forming tungsten thin layers on electrically conducting substrates in a plasma vacuum by decomposing tungsten hexacarbonyl. At present, there are a number of methods and techniques for forming woilfires. Among the most important methods are their application in vacuum by direct evaporation of tungsten, chemical methods and the method of thermal decomposition of tungsten hexacarbonyl on a giant substrate.

So far, methods based on direct evaporation of tungsten in vacuum have become energy intensive and associated with problems caused by high temperature, tungsten evaporation, and low evaporation rate. However, the disadvantages of the chemical processes can be mentioned by the relatively inclusive purity of tungsten layers due to the tungsten oxidation and the increased adhesion of the layers to the substrate.

The disadvantages of the so far used tungsten layer extrusion processes based on thermal decomposition of tungsten hexacarbonyl are the lack of purity due to the high pressure of the argon in the reaction chamber and the high carbon content of the layer due to the thermal decomposition of tungsten hexacarbonyl directly on the substrate surface.

The aforementioned drawbacks are eliminated by the method of forming thin tungsten layers on an electrically conductive substrate, wherein the electrically conductive substrate, which is a kaitone in the ion plating system and a negative electrical potential of 0 to 10 kV, is treated with a vapor plasma. tungsten sublimating hexacarbonyl and an inert gas, usually argon, at a pressure from 10 -3 Pa to 102 Pa at an electrically conductive substrate temperature of up to 550 ° C. The advantage of the method of forming thin layers of tungsten on an electrically conductive substrate is that the layers thus formed achieve high purity with a minimum residual carbon content, which is due to the vacuum and decomposition of tungsten hexacarbonyl under plasma conditions. A further advantage of the method according to the invention is that by changing the electrical parameters in the stimulation of the plasma, the properties of the layers can be controlled, e.g. Ob-

Claims (2)

FREDMET A method of forming thin layers of tungsten on an electrically conductive substrate which is a cathode in an ionic cladding system at a negative electrical potential of 0 to 10 kV over a grounded vacuum chamber, causing the electrically conductive sub-4 to be suppressed by the sublimation rate of tungsten hexacarbonyl. growth rate of tungsten layers. The method of forming tungsten layers on an electrically conductive substrate is documented in the following examples. EXAMPLE 1 The steel washers were placed in a vacuum chamber sucked off and the initial pressure was 13 Pa and subsequently cleaned and heated. Further, argon was pumped into the vacuum chamber to a pressure of 0.1 Pa and was started by sublimation of tungsten hexacarbonyl by means of resistive heating of its reservoir. The evaporation rate of tungsten hexacarbonyl was 1.3 g-min -1. A negative electrical potential of -2.8 kV was attached to the electrically conductive substrate over a grounded vacuum chamber. Under these conditions for 20 min, tungsten layers of 3 µm were formed. The temperature of the substrates was maintained at 300 DEG C. throughout the process 2 Under the same conditions as in Example 1, steel and duralumin substrates were subjected to plasma treatment at an argon pressure of 5 × 10 Pa, a negative electrical potential of ,52.5 kV and - at a sublimation rate of tungsten hexacarbomyl of 2 g. Min -1. tungsten layers of 5 μΐη were formed at 20 ° C under 20 ° C temperature conditions. In the above-mentioned examples of use of the method of the invention, it was verified that the degree of structure, text and spit mechanical could be achieved by changing the pairameters. The properties of the present tungsten layers can be used mainly in areas where a tungsten layer is required for electrically conductive substrates, and in areas where a tungsten backing is required for other layers, it is possible to apply the same. that the tungsten layers on any substrate on which it is electrically conductive the other substance layer is fed with plasma formed by tungsten sublimating vapor-hexacarbonyl vapor and an inert gas, typically argon, at a pressure of 10 -3 Pa-10 Pa and an electrically conductive substrate temperature of 550 ° C.