RU2471705C1 - Method of precipitating monomolecular films of fluorofullerene c60f18 on padding, device for padding introduction into vaccuum and device for fluorofullerene c60f18 evaporation - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention can be used in non-linear optics and pyroelectric devices. Before film precipitation padding is prepared by separation of thin layer from highly oriented pyrographite by means of double-sided adhesive tape. C₆₀F₁₈ powder is loaded into evaporation cell, placed into vacuum chamber, container with prepared padding is installed at the distance from 10 to 40 mm from it. Evaporation of C₆₀F₁₈ powder is performed by heating of evaporation cell to 120-170 °C, supporting padding temperature 18-25 °C. Device of padding introduction into vacuum includes vacuum chamber, sluice device with straight through valve and flange-window for replacement and loading of paddings, rod, made with possibility of reciprocating movement and rotation, holder with padding. Device for fluorofullerene evaporation includes means of mechanical and thermal protection, control and regulation of heating temperature, mounting and positioning of constituting elements, tubular heater and means for placement of evaporated substance. Tubular heater is made in form of quartz tube 8 with coiled outside wire heater 7. Means of mounting and positioning are made in form of stud 4 for console fixation of cell, screw with nut 9 and clamp, located on ceramic pole 11, installed in round base of evaporation cell. Means of positioning include alundum dual channel tube 6 for thermocouple 5.

EFFECT: invention makes it possible to simplify film obtaining, as well as servicing and repair of equipment, reduce energy consumption and increase reliability.

12 cl, 2 dwg

Description

This proposal can be used to obtain and study thin films, various coatings, and nanomaterials with an evaporation temperature of up to 600 ° C. The proposal is aimed at improving the method of deposition of new nanomaterials, which are monomolecular films of fluorofullerene C ₆₀ F ₁₈ on various substrates. In a C ₆₀ F ₁₈ molecule with a size of ~ 1 nm (approximately 1 nm), 18 fluorine atoms are grouped only on one side of the C ₆₀ framework, which leads to a large electric dipole moment (EDM), about 10–13 Debye. Due to this, the C ₆₀ F ₁₈ molecule can exhibit ferro- or pyroelectric properties, i.e. this compound can be interesting from the point of view of creating ordered structures necessary for applications in nonlinear optics, pyroelectric and other devices. Of particular relevance to the work is the possibility of creating thin monolayer EDM polarized coatings in which the molecules are strictly oriented along one direction. Currently, the processes of deposition of thin films of C ₆₀ F ₁₈ on various substrates have not been studied. In addition, the cell and the vacuum chamber constituting this proposal have a simpler design than those currently used, and can be used to produce films of various materials under high or low vacuum conditions in small commercial firms in an economical spraying mode, which is especially important for the evaporation of expensive and / or aggressive materials.

State of the art

Among the known methods of thermal vacuum evaporation with the deposition of monomolecular layers of C ₆₀ and C ₇₀ fullerenes, there is the most common method of evaporation using a “boat” of refractory metals such as W, Ta, Mo, as, for example, in T.Ohno, S. Yatsuya " Growth offullerene nanoparticles prepared by the gas-evaporation technique. " Journal of Materials Science, 33 (1998) 5843-5847 / 1 / upon evaporation of powders C ₆₀ and C ₇₀ from a tungsten boat:

"... The purity of the starting materials (Texas Fullerenes Corp.) was 99.9% for C ₆₀ and 99% for C _70. Evaporation was carried out in most cases from a tungsten boat (6 × 80 × 0.1 mm ³ ) heated to a temperature of T _s in ranging from 1000 to 1300 ° C in an argon atmosphere at a pressure of Ar from 0.7 to 2.6 kPa. to investigate the effect of the evaporation temperature on the crystal structure and habit nanoparticles C ₇₀ powder C ₇₀ evaporated from a tantalum boat which was covered with a tantalum piece with two pinhole holes (eng. pinhole), which was heated to Ts = 1750 ° C.

(pinhole - a small hole in the micron region, "pin hole") see, for example: "Encyclopedias Stenop - Wikipedia, en.wikipedia.org").

Samples for research using electron microscopy were collected after 1 second of evaporation at various lateral distances L from the sprayed center and at a vertical distance V from the boat ... "

The disadvantage of the method of deposition / 1 / from the boat is, in particular, a large amount of expendable powder C ₆₀ (costing about 1000 Euro per 1 g), which is economically ruinous when using this spraying method.

Evaporation is also carried out from industrial crucibles of various types, as, for example, described in the work of A. Goldoni, G. Paolucci "The interaction of C ₆₀ with Ag (100):

strong predominantly ionic bonding ", Surface Science 437 (1999) 353-361, / 2 /, where C ₆₀ powder from Ta crucible was evaporated on an Ag substrate at a temperature of 700 K or several monolayers were deposited on a substrate at room temperature and then heated to 700K (to desorb excess and leave 1 monolayer).

The disadvantage of this spraying method is the use of a larger amount of powder for spraying a thicker film, as well as the formation of additional defects during the evaporation of this thick film to a monomolecular thickness.

An evaporator such as a boat or crucible, as well as evaporation from them, can be considered as well-known solutions-analogues to the proposed solution (evaporation method and device).

The use of the Knudsen WKC3 cell in the evaporation of metals is reported, for example, in the dissertation of Bjørn FISCHER (on page 9): NUCLEATION AND GROWTH IN METAL-ON-METAL EPITAXY: THE INFLUENCE OF STRAIN AND SURFACE RECONSTRUCTION THÈSE No. 1773 (1998), see http://ipn2.epfl.ch/LSEN/jvb/pdf_files/Bjørn_thesis_1998.pdf/...(3).

In addition, in the USA and Germany there are a number of companies that produce a variety of Knudsen cells, for example, these are AJA International Inc. Evaporation Systems (USA), Comstock Inc. (USA), Toras (USA, http://www.topac.com/kcel.html), Tectra GmbH (Germany), Henniker Scientific (Germany). Most of these cells are used for high-temperature evaporation of films (250-1500 ° С) over a large area and have large dimensions and the used power of heaters (from 125 W to 3.5 kW).

As a prototype for the Method of deposition of monomolecular films of C ₆₀ F ₁₈ fluorofullerene onto a substrate, a publication is selected (see the article "VMMikoushkin et al, Core Electron Level structure in C ₆₀ F ₁₈ Fluorinated Fullerenes ...").

However, this decision has the following disadvantages:

- high energy intensity, unreliability in operation.

- the complexity of manufacturing, maintenance and repair,

- shortcomings in the assortment of finished products, in the range of evacuation - for use in the preparation of films of different materials in high or low vacuum conditions in an economical spraying mode when evaporating expensive and / or aggressive materials.

The proposed solution provides a technical result, consisting in the following:

- reduced energy intensity, increased reliability in operation.

- simplified manufacturing, maintenance and repair processes,

- shortcomings in the assortment of finished products in the vacuum range have been eliminated - for use in the production of films of different materials in high or low vacuum conditions in an economical spraying mode during the evaporation of expensive and / or aggressive materials.

The specified provided by the proposed combination of essential features.

The method of deposition of monomolecular films of C ₆₀ F ₁₈ fluorofullerene on a substrate includes the steps of preparing the substrate, evaporating the C ₆₀ F ₁₈ powder in a vacuum chamber and depositing its monomolecular film on the substrate, wherein

- the C ₆₀ F ₁₈ powder is loaded into the evaporation cell, the evaporation cell with the powder is introduced into the vacuum chamber, the container with the substrate for spraying the film in the vacuum chamber is installed, and the preparation of the substrate consists in separating thin HOPG highly oriented pyrolytic graphite with the help of double-sided adhesive tape layer and placing it in the container immediately before loading into the vacuum chamber, the vacuum evacuation of the chamber is carried out until a base vacuum of about 10 ^-9 IBA Before evaporation produce powder degassing evaporation cell powder C ₆₀ F ₁₈ via the warm-evaporation cell to a temperature 110-120 ° C for 12-15 hours under vacuum treatment, evaporation powder C ₆₀ F ₁₈ produced by heating the evaporation cell to a temperature of 120 -170 ° C, thin film C ₆₀ F _{18 is} deposited on substrates having a maintained temperature of 18-25 ° C, the substrate is placed at a distance of 10 to 40 mm from the body of the evaporation cell;

- heating the evaporation cell with the powder is carried out to a temperature of powder evaporation of C ₆₀ F ₁₈ 140-160 ° C with a heater power of 2-3 W using a DC power source, while creating a vacuum no worse than 7 × 10-9 mbar;

- the process of film deposition is carried out on a substrate up to a diameter of 7-10 mm and is carried out up to a film thickness of 0.1 to 1 monolayer;

- the distance from the housing of the evaporation cell to the substrate s is selected within 15-25 mm .;

- the deposition rate of the film is selected in the range of 0.01-0.1 nm / s.

The prototype for a device for introducing a substrate into a vacuum is a.c. SU 322421, CL С23С 13/08, 1972, "VACUUM SPRAY INSTALLATION", / The invention relates to the production technology of radio equipment and can be used for the manufacture of integrated cryotropic circuits by spraying through stencils ... /.

However, the indicated solution did not provide for simplicity of design, expansion of the range of finished products, expansion of the vacuum range — for use in the preparation of films of different materials under high or low vacuum in an economical spraying mode when evaporating expensive and / or aggressive materials, improving the quality of the resulting product, reducing energy intensity of equipment, maintainability.

The technical problem to which the invention is directed is to create a simpler design than currently used, expand the range of finished products, expand the vacuum range for use in the production of films of different materials under high or low vacuum in an economical spraying mode when expensive and / or aggressive materials, improving the quality of the resulting product, reducing the energy intensity of equipment, increasing maintainability.

The solution to this technical problem is provided by a set of essential features of the proposed solution, namely:

a device for introducing substrates into a vacuum for deposition of monomolecular fluorofullerene films on them, including a vacuum chamber having a flange, a lock device for changing and loading substrates into a vacuum chamber, configured to periodically cut off from the volume of the vacuum chamber, a rod made with the possibility of reciprocating movement holder with backing,

wherein

the gateway device is equipped with a straight-through valve, the rod is rotatable around the direction of its reciprocating movement, the substrate is fixed to the holder by means of a container inserted into the device and placed in the container, the container being threadedly connected to the holder, the rod and container are equipped with bayonet means for interconnecting each other while the lock device for changing and loading the substrates into the vacuum chamber is equipped with a flange-window.

Wherein

- the manipulator is placed in a vacuum chamber with the ability to position the substrate from the evaporation cell at a distance s within 10-40 mm;

- the evaporation cell is made with a diameter of d 20-25 mm;

- at least one of the flanges of the vacuum chamber is made with a passage diameter of more than 25 mm

The prototype device for the evaporation of fluorofullerene C ₆₀ F ₁₈ is the publication of an article by M. Khodorkovsky et al., Gas-dynamic parameters of a supersonic molecular beam enriched in fullerene molecules (Journal of Technical Physics, 2003, v.73, issue 5, pp. 1-4, Fig. 1).

The technical problem solved by the proposed solution and, accordingly, the technical result consists in:

- the use of a more economical evaporator, in terms of consumption of the evaporated material,

- reducing cost, energy consumption, simplifying maintenance, repair, expanding functionality,

- the ability to spray any materials with an evaporation temperature of up to 600 ° C,

- reducing the power of the heater, which when spraying polycrystalline

C ₆₀ F ₁₈ powder is less than 3 W,

- miniaturization of the cell, which also leads to a low inertia of the cell (it quickly heats up and cools down), to the deposition of small areas with a film size of less than 10 mm and to the economical use of the sprayed material (in this case, scarce C ₆₀ F ₁₈ polycrystalline powder).

The implementation of this is provided by a combination of essential features.

The device for the evaporation of fluorofullerene C ₆₀ F ₁₈ includes a limited volume in the form of an evaporation cell, a tubular heater, means for accommodating the vaporized substance, and it is additionally equipped with mechanical and thermal protection, including an external fence, means for controlling and regulating the heating temperature, mounting and positioning means of constituent elements, the tubular heater is made in the form of a quartz tube with a wire heating element wound from the outside, mounting means and position the component elements are made in the form of a stud for cantilever mounting of the cell, a screw with a nut, and a clamp for attaching the leads of the wire heater placed on a ceramic rack installed in the round base of the evaporation cell,

wherein

- the heating element is made of tungsten-rhenium wire;

- positioning means include placed in the cavity of the quartz tube alundum double channel tube.

The proposed solution is illustrated graphically presented illustrations.

In Fig.1 - evaporation cell (upgraded Knudsen cell), pos.16 in Fig.2 (enlarged).

Figure 2 - device for introducing substrates into a vacuum, where the positions indicated:

1 - the round base of the evaporation cell 16 (Knudsen cell);

2 - a hollow glass where the evaporated substance is placed;

3 - the bottom of the hollow glass 2;

4 - hairpin for cantilever mounting the cell inside the cell chamber;

5 - thermocouple (in the hole in the bottom of the glass 2);

6 - alunda two-channel tube for a thermocouple;

7 - wire heater cup 2;

8 - quartz tube;

9 - screw with nut for fastening the conclusions of the wire heater 7;

10 - clamp for mounting the conclusions of the wire heater 7;

11 - ceramic rack;

12 - casing of the evaporation cell (Knudsen cell);

13 - screw fastening the casing 12;

14 - hole for the exit of the evaporated material from the hollow glass 2;

15 - a vacuum chamber;

16 - evaporation cell (Knudsen cell);

17 - flange for the evaporation cell 16;

18 - gateway device;

19 - flange mounting gateway device;

20 - substrate;

21 is a container for transferring a substrate;

22 - container holder;

23 - straight-through valve;

24 - a flange-window for entering a container with a substrate from the atmosphere into the gateway;

25 - stock.

The entire design of the evaporation cell 16 (figure 2) is shown in detail in figure 1. All parts of the evaporation cell 16 are fixed on a circular base 1. The diameter of the cell is d = 20-24 mm, and the length of the part covered by a cylindrical casing is selected within 40-45 mm. The evaporator itself consists of a hollow cup 2 (for accommodating the evaporated material, for example, powder C ₆₀ F ₁₈ ), which is screwed onto the bottom 3 by thread. The bottom 3 is fastened with nuts 4 (diameter 2.0-2.5 mm) to the base 1. B bottom 3 there are two holes for a thermocouple 5, the wires of which are led through an alundum two-channel tube 6. A wire heater 7 is freely wound around a quartz tube 8. Without ends, the ends of the wire heater are fixed with screws 9 and nuts M2 on metal clamps 10 The clamps 10, in turn, are crimped around the ceramic pillars 11. The entire structure is closed by a casing 12, mounted on screws 13.

It should be borne in mind that “the casing of the evaporation cell 12 is, by its function, its“ external enclosure ”.

The glass 2 has an opening 14 for the exit of the evaporated material.

The location of the evaporation cell, airlock device and the substrate in the vacuum chamber is shown in Fig.2.

Figure 2 shows the vacuum chamber 15, the evaporation cell 16, mounted on the flange 17, the gateway device 18, mounted on the flange 19, and the substrate 20, on which the material is sprayed from the evaporation cell 16.

When designing the evaporation cell 16, the following circumstances were taken into account:

- the cell should heat up as quickly as possible, so that at the minimum time of transitional evaporation, it reaches the desired temperature mode with the minimum electric heating power, in order to avoid heating of the surrounding parts and to reduce the desorption of gases from them. For this, the size and mass of the evaporator itself (the evaporation cell 16) are made minimal, and its fastening is made cantilever, i.e. on one thin long hairpin 4 with a diameter of ⌀ 2-3 mm made of austenitic stainless steel to reduce heat loss in the fasteners (austenitic stainless steel has a minimum thermal conductivity of all metals). A hollow glass 2 cells, screwed to the bottom 3, is placed in a transparent quartz tube 8 and closed with a thin-walled casing 12 made of stainless steel;

- with a small size of the evaporation cell with a “hanging” horizontal position of the heating element made of wire (wire heater 7) it is difficult to avoid short circuits due to thermal deformations, therefore, the heated evaporator is placed in a transparent quartz tube 8, onto which the heating element 7 is wound freely, without direct contact : tungsten-rhenium wire with a diameter of 00.35 mm / from 0.3 to 0.4 mm / (pure tungsten easily breaks after heating by shaking the cell during installation, etc.).

In addition, the need to control the temperature of the evaporator using thermocouples (to increase reliability, two duplicate chromel-alumel thermocouples are used) in combination with the need to load the sprayed material from time to time makes it possible to mount the thermocouples on a fixed part of the evaporator that is not removed when loading. In this regard, the evaporator is made of two unscrewable parts: a fixed bottom 3 with an external thread, which is fixed on the console stud 4 and into the openings of which two thermocouples 5 are inserted, and a cup 2 screwed onto this bottom, forming together with the bottom 3 a hollow chamber with hole 14 for the departure of the evaporated material.

The substrate 20 is mounted on the container 21, which, in turn, is screwed into the holder 22 of the container. The holder 22 of the container is mounted on the axis of the manipulator (not shown in FIG. 2). The manipulator allows you to transfer the movement of the substrate 20 when it is in the evacuated volume - rotation and linear movement and, thus, turn the substrate 20 to the evaporation cell and turn the substrate away from it. In addition, the manipulator is necessary in order to put the bayonet connector of the container 21 in position with respect to the rod 25 at the time of transfer of the container 21 with the substrate 20 to the container holder 22 and vice versa.

The substrates located in the vacuum chamber can be replaced without air inlet through the airlock 18, which has a direct-flow valve 23, a flange-window 24 for the input (and output) of the container 21 with the substrate 20 from the atmosphere into the airlock, followed by pumping. The flange window 24 is used not only for input-output of the container, but also for visual control of its movement. Using a bayonet connection, the container is put on the rod 25 through the open flange-window 24 (the direct-flow valve is closed), the flange-window is closed, the sluice volume is evacuated (pumping devices are not shown), the direct-flap valve 23 is opened and, using the linear movement of the stem 25 (from the side of the atmosphere, the rod is sealed by the pressed fluoropolymer rings) the container is brought to the container holder in a vacuum chamber and screwed into the container holder. After that, the stem is manually rotated and translationally withdrawn from the bayonet connection with the container, removed from the vacuum chamber to the airlock and the direct-flow valve closes. Thus, the substrate with the container is detached from the rod and is screwed into the container holder on the manipulator.

Two substrates are used as substrates 20 for spraying monomolecular films of C ₆₀ F ₁₈ powder:

1) 0.5 mm thick Si (111) silicon wafer doped with boron (to create conductivity), which is used for initial debugging of the deposition device and control of the deposited C ₆₀ F ₁₈ / Si (111) film and the used C ₆₀ F ₁₈ powder using the procedure infrared spectroscopy and Raman spectroscopy;

2) highly oriented pyrolytic graphite (HOPG mosaic spread 3.5

- 5.0 degrees) square in size of 8 × 8 mm ² - the main deposition of thin films is carried out on it.

The mode of deposition of thin films C ₆₀ F ₁₈ , which includes the following operations, has been developed.

1. Loading C ₆₀ F ₁₈ powder into the evaporation cell 16 (Knudsen cell) in the vacuum chamber 15 (in the USU-4 chamber) and installing the container 21 of the substrate 20 for spraying the film.

For the substrate 20 made of HOPG graphite, the preparation of the substrate 20 consists in separating a thin graphite layer from the graphite plate (using double-sided adhesive tape) and placing it in the container container 21 immediately before loading into the vacuum chamber 15.

2. Vacuum pumping of the vacuum chamber 15 (USU-4 chambers) to obtain a basic vacuum of approximately 10 ^-9 mbar.

3. The degassing of the evaporation cell 16 (Knudsen cell) with C ₆₀ F ₁₈ powder by vacuum heating the evaporation cell to a temperature of 110-120 ° C for 12-15 hours to desorb the water molecules.

4. Evaporation of C ₆₀ F ₁₈ powder by heating to a temperature of 120-170 ° C. Deposition of a thin film of C ₆₀ F ₁₈ on substrates replaced from the atmosphere through a gateway and at room temperature.

C ₆₀ F ₁₈ powder is loaded into a hollow beaker 2, the evaporator is heated (beaker 2 and bottom 3) by passing current through a heater 7 wound on a quartz tube 8, inside which beaker 2 is placed, the C ₆₀ F ₁₈ powder is heated to a temperature of 120- 170 ° C evaporates and flies out through the cone-shaped opening of chamber 2 and is deposited on a substrate of 0.5 mm thick Si (111) silicon wafer doped with boron, or on a substrate of highly oriented pyrolytic graphite (HOPG), forming

the sprayed film in a given geometry, i.e., with a diameter of 7-10 mm, at a distance s from the body of the evaporation cell 16 (Knudsen cell) to the substrate 20 of 10-20 mm, and

with the inner diameter of the vacuum chamber 15 (for example, for USU-4), ⌀ 250 mm in the position shown in the illustration (Figure 2).

In a specific implementation example:

The evaporation temperature of the powder C ₆₀ F ₁₈ was 150 ° C at a heater current of 1.2 A, a voltage of 1.8 V (i.e., power 2.2 W, DC source B5-71) and a pressure of 2.7 × 10 ^{- 9} mbar. The size of the sprayed film in this geometry was 8 mm at a distance s from the body of the Knudsen cell to the substrate of 17 mm and with an inner diameter of the vacuum chamber USU-4 = ⌀250 mm. The powder evaporation time ranged from 6 sec (film thickness of about 0.1 monolayer) to 60 sec (1 monolayer), which corresponds to the required low deposition rate of 0.01-0.1 nm / s to obtain high-quality coatings.

Object of invention

The method can be characterized by the following set of essential features (with the necessary explanations).

The method of deposition of C ₆₀ F ₁₈ fluorofullerene monomolecular films on various substrates includes the steps of preparing a substrate, loading C ₆₀ F ₁₈ powder into a Knudsen cell in a USU-4 chamber and installing a container with a substrate for spraying the film, heating the substrate with the powder to the temperature of the powder to evaporate, wherein for HOPG graphite, the preparation of the substrate consists in separating a thin layer with graphite tape from graphite and placing it in a container immediately before loading into the vacuum chamber (USU-4), vacuum pumping the chamber USU-4 to obtaining a basic vacuum of approximately (~) 10 ^-9 mbar, degassing the Knudsen cell with C ₆₀ F ₁₈ powder by vacuum heating the cell to a temperature of 110-120 ° C for 12-15 hours until optimal desorption of water molecules, deposition of a thin C ₆₀ film F ₁₈ on substrates having a maintained temperature of 18-25 ° C (“at room temperature”), placing the substrate from a Knudsen cell body at a distance of 10 to 40 mm.

Moreover, heating the substrate with the powder is carried out to a powder evaporation temperature of C ₆₀ F ₁₈ 140-160 ° C, at a heater current of 1.2 A, a voltage of 1.8 V (i.e., a heater power of 2.2 W, using a B5 DC source -71) under a vacuum of 2.7 × 10 ^-9 mbar;

- the process of spraying a film on a substrate is carried out to a thickness of 0.1-1 monolayer with a film diameter of 7-10 mm;

- the distance from the body of the Knudsen cell to the substrate is chosen within s = 15–25 mm and with an internal diameter of the USU-4 vacuum chamber ⌀ 250 mm;

- deposition rate - 0.01-0.1 nm / s.

In this case, the evaporation time of the films ranged from 6 sec (film thickness of about 0.1 monolayer) to 60 sec (1 monolayer), which corresponds to the required low deposition rate of 0.01-0.1 nm / s to obtain high-quality coatings.

A device for introducing substrates into a vacuum was also manufactured and tested - explained in FIG. 2.

So, figure 2 shows an example of the location of the evaporation cell 16 inside the vacuum chamber 15 relative to other nodes commonly used in the deposition of films (top view) - a device for introducing substrates into a vacuum.

The vacuum chamber 15 has flanges 17 and 19, on which, respectively, an evaporation cell 16 (Knudsen cell), a gateway device 18 for changing and loading substrates into ultra-high vacuum, and a manipulator for turning the substrate 20 are located (the manipulator itself is located above the drawing plane and is not shown ), therefore, the said flanges 17 and 19 are an integral part of the vacuum chamber 15.

The holder 21 of the container is located on the shaft of the manipulator of the substrate and consists of the holder 22 of the container, in the threaded hole of which is screwed the actual container 21 with the substrate 20 fixed on it.

While the substrate 20 is not transferred from the lock device 18 to the vacuum chamber 15 or vice versa, the volume of the lock is cut off from the vacuum chamber by a straight-through valve 23. To install the substrate in the vacuum chamber 15, the container 21 with the substrate 20 fixed on it is placed in the lock volume on the stem 25 using a bayonet connection, pump out the sluice volume, open the direct-flow valve 23, and by linear movement of the stem 25 manually transfer the substrate to the vacuum chamber 15. The stem can not only move along the axis, but also rotate wok y axis, and because of this possibility container 21 is screwed on the thread of the container carrier. After that, the rod is released from the bayonet connection, leaving the container with the substrate in the holder, and extends from the vacuum chamber 15 back into the lock device. Then the connection of the vacuum chamber with the gateway is blocked by a direct-flap valve 23. The input and output of the substrates from the gateway is made through the flange-window 24 with a removable viewing window.

The substrate is rotated using the manipulator to the evaporation cell, and spraying begins. Spraying can occur at a distance s = 10-20 mm from the spray cell to the substrate, but if necessary, reduce the speed of the sprayed stream, the distance s can be easily increased. The evaporation cell has a diameter of d = 20-25 mm and can fit on any flange of the vacuum chamber with a passage diameter of more than 25 mm, which significantly reduces the cost of the design of the vacuum chamber.

Thus, the object of the invention “Device” can be characterized by the following set of essential features (with the necessary explanations).

The device for introducing substrates into a vacuum includes a vacuum chamber 15 having a flange for the evaporation cell 17, a sluice device 18 having a flange-window 24 (for changing and loading the substrates in ultra-high vacuum) placed in the vacuum chamber 15 with the possibility of positioning the substrate 20 relative to the outlet evaporation cell 16, a manipulator having a container holder 16 located on the shaft of the manipulator, having a threaded connection with the container 21 with the substrate 20 fixed therein, arranged to periodically cutting off the volume of the sluice device 18 from the volume of the vacuum chamber 15, a direct-flow valve 23 mounted in the sluice device 18 with the possibility of reciprocating axial movement and rotation around the axis, the rod 25 having bayonet means for connecting to the container 21, and the flange-window 20 is provided removable viewing window

wherein

- the manipulator is placed in the vacuum chamber 15 with the possibility of positioning

the substrate from the spray cell at a distance s in the range of 10-40 mm;

- the evaporation cell is made with a diameter of d = 20-25 mm;

- at least one of the flanges of the vacuum chamber is made with a passage diameter of more than 25 mm

Accordingly, another object of the invention “Device” can be characterized by the following set of essential features (with the necessary explanations).

A device for the evaporation of fluorofullerene C ₆₀ F ₁₈ , comprising a limited volume in the form of an evaporation cell 16, a tubular heater, means for accommodating the vaporized substance, made in the form of a hollow cup 2 having a bottom 3 from one end and an exit opening 14 from the opposite end the evaporated material, means of mechanical and thermal protection, including an external fence (casing 12), means for controlling and regulating the heating temperature, means for mounting and positioning the constituent elements,

differs in that

the tubular heater is made in the form of a quartz tube 8 with a wire heating element 7 wound from the outside,

means for mounting and positioning the constituent elements are made in the form of a stud 4 for cantilever mounting of a cell, an alundum two-channel tube 6 for a thermocouple placed in the cavity of a quartz tube 8, a screw 9 with a nut and a clamp 10 for attaching the leads of a wire heater 7 placed on a ceramic rack 11, installed in the circular base 1 of the evaporation cell 16.

Thus, this solution will allow to obtain films of fluorofullerene C ₆₀ F ₁₈

in an economical spraying mode, which can currently be used in nonlinear optics, in pyroelectric and other devices. Of particular relevance to the work is the possibility of creating thin monolayer EDM polarized coatings.

Claims (12)

1. The method of deposition of monomolecular films of fluorofullerene C ₆₀ F ₁₈ on a substrate, comprising the steps of preparing the substrate, evaporating the C ₆₀ F ₁₈ powder in a vacuum chamber and depositing its monomolecular film on the substrate, characterized in that the C ₆₀ F ₁₈ powder is loaded into the evaporation cell , an evaporation cell with powder is introduced into the vacuum chamber, a container with a substrate for spraying a film in a vacuum chamber is installed, and the preparation of the substrate consists in separating with a double-sided adhesive tape from the high ientirovannogo pyrographite HOPG thin layer and placing it into the container immediately before loading into the vacuum chamber, the vacuum evacuation of the chamber is carried out until a base vacuum of about 10 ^-9 mbar to produce a powder by evaporation degassing evaporation cell powder C ₆₀ F ₁₈ by warming the evaporator cell to a temperature of 110-120 ° C for 12-15 hours under vacuum, the evaporation of the powder C ₆₀ F _{18 is} produced by heating the evaporation cell to a temperature of 120-170 ° C, the deposition of a thin film C ₆₀ F ₁₈ pr produced on substrates having a maintained temperature of 18-25 ° C, the placement of the substrate is carried out at a distance of 10 to 40 mm from the body of the evaporation cell. 2. The method according to claim 1, characterized in that the heating of the evaporation cell with the powder is carried out to a temperature of powder evaporation of C ₆₀ F ₁₈ 140-160 ° C at a heater power of 2-3 W, using a DC power source, while creating a vacuum not worse than 7 · 10 ^-9 mbar. 3. The method according to claim 1, characterized in that the film is sprayed onto a substrate up to a diameter of 7-10 mm and is carried out up to a film thickness of 0.1 to 1 monolayer. 4. The method according to claim 1, characterized in that the distance from the housing of the evaporation cell to the substrate s is selected within 15-25 mm. 5. The method according to claim 1, characterized in that the film deposition rate is selected in the range of 0.01-0.1 nm / s. 6. A device for introducing substrates into a vacuum for deposition of monomolecular fluorofullerene films on them, including a vacuum chamber having a flange, a lock device for changing and loading substrates into a vacuum chamber, configured to periodically cut off from the volume of the vacuum chamber, a rod configured to return translational movement, a holder with a substrate, characterized in that the lock device is equipped with a straight-through valve, the rod is made to rotate around its direction of return translational movement, the substrate is fixed to the holder by means of a container inserted into the device and placed in the container, the container having a threaded connection with the holder, the rod and container are equipped with bayonet means for interconnecting each other, while the lock device for changing and loading the substrates into the vacuum chamber is equipped with a flange by the window. 7. The device according to claim 6, characterized in that the manipulator is placed in a vacuum chamber with the ability to position the substrate from the evaporation cell at a distance s within 10-40 mm. 8. The device according to claim 6, characterized in that the evaporation cell is made with a diameter of d = 20-25 mm 9. The device according to claim 6, characterized in that at least one of the flanges of the vacuum chamber is made with a passage diameter of more than 25 mm 10. A device for the evaporation of C ₆₀ F ₁₈ fluorofullerene, including a limited volume in the form of an evaporation cell, a tubular heater, means for accommodating the vaporized substance, characterized in that it is additionally equipped with mechanical and thermal protection, including external fencing, with means for controlling and regulating the heating temperature by means of mounting and positioning of the constituent elements, the tubular heater is made in the form of a quartz tube with a wire heating element wound from the outside, means mounting and positioning of the constituent elements are made in the form of a stud for cantilever mounting of the cell, a screw with a nut and a clamp for mounting the conclusions of the wire heater, placed on a ceramic rack installed in the round base of the evaporation cell. 11. The device according to claim 10, characterized in that the heating element is made of tungsten-rhenium wire. 12. The device according to claim 10, characterized in that the positioning means include a double-channel alundum tube located in the cavity of the quartz tube.

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