JP5179716B2 - Electron beam vacuum deposition method and apparatus - Google Patents

Description

  The present invention relates to an electron beam vacuum deposition method and apparatus.

The vacuum deposition method is a method in which a film-forming substance (evaporation substance) is heated to a vapor pressure temperature or higher under vacuum to evaporate, and the evaporation substance is attached to a substrate disposed oppositely.
As a heating method for the film forming substance, a resistance heating method for energizing a container containing the film forming substance, a heater heating method for heating the container with a heater disposed on the outer periphery of the container, and an electromagnetic induction action of an induction coil outside the container are used. Alternatively, an induction heating method for heating the film forming material itself, an electron beam evaporation method for directly evaporating the film forming material by irradiating the film forming material in the container with an electron beam from the outside, and the like are generally known.
In particular, in the production of mass-produced products, most materials such as high melting point ceramic materials such as metal materials and oxides can be deposited, the supply of deposition materials is easy, and the control of the deposition rate is excellent. Therefore, the electron beam evaporation method is mainly used.

On the other hand, organic devices such as organic light-emitting elements, organic transistors, and organic solar cells have been manufactured with the recent development of organic electronics. For example, an organic electroluminescence (EL) element is known as an organic light emitting element. In this element, a thin film of an organic material having a light emitting function is formed on a substrate, the thin film is sandwiched between an upper electrode and a lower electrode, and a voltage is applied between the electrodes so that the organic material emits light.
As a driving method of this element, the upper electrode and the lower electrode are wired in a matrix form vertically and horizontally, and each wiring is connected to the electrode, and a driving circuit (thin film transistor: TFT) is provided for each pixel. There is an active matrix method for controlling. Since the passive system has a simple structure, it is suitable for manufacturing a simple display at a low cost. On the other hand, the active method has a fast switching operation and is suitable for a television or the like, and is expected to become the mainstream in the future.

An EL element is usually manufactured by forming a drive circuit such as a TFT on a substrate and then forming each electrode and an organic thin film by a vacuum deposition method. Since the binding energy of the organic material in the organic thin film is low, when the metal layer to be an electrode is formed by sputtering, plasma particles (high energy particles) by sputtering deteriorate the organic material, so the metal layer is also formed by vapor deposition. .
By the way, as a method for depositing an organic thin film, a resistance heating method is used when a small amount is deposited by an experimental apparatus or the like, but a heater heating method or an induction heating method is usually used in a mass production device. In addition, as described above, an electron beam vapor deposition method suitable for manufacturing a mass-produced product is usually used as the metal film vapor deposition method.

However, when the electron beam evaporation method is used in the film forming process, a problem has been pointed out that X-rays are generated from the evaporation source and the gate voltage of the TFT is changed (for example, see Patent Document 1).
For this reason, a technique for forming a film by irradiating the deposition material with an electron beam to release the vapor and then stopping the emission of the electron beam and moving the film formation target to a position where the vapor reaches is disclosed. (For example, refer to Patent Document 2). According to this technique, since the film is formed by the residual heat, the electron beam is not irradiated to the film formation target, and the above-described damage is not caused.

JP 2004-63085 A (Solution means) JP 2004-131831 A (Solution means)

However, in the case of the technique described in Patent Document 2, the moving distance becomes longer because the moving object becomes larger when the substrate to be deposited becomes larger. As a result, there is a problem that the tact time is increased and the film formation efficiency is lowered, and the uniformity of the film formation distribution in the moving direction of the substrate is also lowered.
The present invention has been made to solve the above-described problems, and can perform evaporation without affecting the object of film formation, and is an electron beam vacuum excellent in film formation efficiency and film formation distribution uniformity. An object of the present invention is to provide a vapor deposition method and an apparatus therefor.

In order to achieve the above object, an electron beam vacuum vapor deposition method of the present invention is a vacuum vapor deposition method for depositing an evaporation substance contained in a container having an opening on a film deposition target, the container and the film deposition. The object is placed in a vacuum evacuated chamber, and the opening of the container does not face the film formation target, and the electron is at a first position where a shielding partition plate is interposed between the opening and the film formation target. A heating step of irradiating the evaporating material with a beam to heat the evaporating material, and moving the container to a second position opposite to the film formation target, causing the evaporating material to be released from the opening by residual heat, and A film forming process for forming a film on a film forming target and a position returning process for returning the container from the second position to the first position are repeated in this order.
In this case, when vapor deposition is performed on a film formation target (a substrate or the like), only the remaining heat is used without heating, so that X-rays or the like do not reach the film formation target due to electron beam irradiation used for heating. Further, since the container is moved instead of the film formation target, even when the film formation target becomes large, the film formation efficiency and the uniformity of the film formation distribution are less likely to decrease.

In the electron beam vacuum deposition method of the present invention, two or more containers are provided, and one container is moved to the second position and another container is moved to the first position while the film forming process is performed. When the film formation by the one container is completed, the film formation process is continuously performed by moving the other container to the second position and performing the film formation process. Preferably it is done.
Further, the evaporated substance released from the container can be shielded.
In the heating step, the electron beam can be either a straight traveling direction or a deflected traveling direction.

An electron beam vacuum deposition apparatus according to the present invention includes a container containing an evaporating substance and having an opening, a heating mechanism for generating an electron beam for heating the evaporating substance, a moving mechanism for moving the container, a shielding partition plate, , comprising a film forming object, the container, the heating mechanism, the moving mechanism and the shielding partition plate is disposed in a vacuum evacuated chamber, said heating mechanism, opening of the container and the film-forming target The evaporating substance is heated by irradiating the evaporating substance with the electron beam at a first position where the shielding partition plate is interposed between the opening and the deposition target without facing, the moving mechanism includes A film forming step of moving the container, which has been heated at the first position, to a second position facing the film formation target and discharging the evaporated substance from the opening by residual heat to form a film; Return the container after the membrane to the first position. Position back a step and repeating in this sequence.

  In the electron beam vacuum deposition apparatus of the present invention, two or more containers are provided, and the moving mechanism moves one container to the second position and performs another film formation process while performing the film forming step. The film forming step is performed by moving the first container to the position 1 and performing the heating process, and when the film formation by the one container is completed, moving the other container to the second position and performing the film forming process. It is preferable to carry out the process continuously.

  According to the present invention, it is possible to perform deposition without affecting the film formation target by preventing irradiation of the film formation target such as X-rays generated from an electron beam, and uniform film formation efficiency and film formation distribution. Can be improved.

Hereinafter, embodiments of the present invention will be described.
<First Embodiment>
FIG. 1 is a perspective view showing an example of an electron beam vacuum deposition apparatus according to the first embodiment of the present invention. The apparatus according to this embodiment is an example in which an organic EL element is manufactured, and an electron beam (hereinafter abbreviated as EB) is used as an energy source for evaporating a metal material used as a wiring of the element. In addition, a TFT element is provided in advance on a substrate which is a film formation target.
In FIG. 1, an electron beam vacuum deposition apparatus 50 is disposed in a chamber (not shown) (for example, evacuated to about 5 × 10 ⁻⁴ Pa). The electron beam vacuum vapor deposition apparatus 50 moves the positions of two containers 2A and 2B that contain an evaporated substance (metal material), an electron beam source (heating mechanism) 6 that generates an electron beam 32, and the containers 2A and 2B. A moving mechanism 8A to be moved, a shielding partition plate 10, and a substrate holder (not shown) are provided. A substrate 20 is attached to the substrate holder. The moving mechanism 8 is controlled by a control unit (not shown).

  In the substrate holder of this embodiment, the substrate 20 is rotated about the rotation center 22 as an axis. When the size of the substrate 20 is large, the substrate is usually rotated to form a uniform film (rotary film formation).

Each of the containers 2A and 2B has a bottomed cylindrical shape, and has openings 4A and 4B on the upper surface, respectively. The electron beam source 6 generates thermoelectrons from a built-in filament, draws out an electron beam by controlling a built-in electromagnet, and irradiates the evaporated material with the electron beam from the openings 4A and 4B of the containers 2A and 2B.
The moving mechanism 8A has a pedestal that can reciprocate on the track. The container 2A is disposed on the upper right surface of the moving mechanism 8A, and the container 2B is disposed on the upper left surface of the moving mechanism 8A. In FIG. 1, the moving mechanism 8A reciprocates in the left-right direction, and the control of the moving mechanism 8A is performed by a control unit (not shown).
1, with the moving mechanism 8A moved to the leftmost side, the shielding partition plate 10 is positioned above the container 2A, and the electron beam source 6 is adjacent to the container 2A (the container is at this position). Time is referred to as the “heating position”). Further, in this state, the lower surface of the substrate 20 is exposed above the container 2B (opening 4B) (when the container is in this position, it is referred to as “evaporation position”).

FIG. 2 shows a front view seen from the direction F of FIG. In FIG. 2, the container 2B is positioned on the left side of the shielding partition plate 10, and the evaporated particles 30 from the container 2B reach the surface of the substrate 20 on the left side of the rotation center 22 (heating position). The center of the container 2A is the same as the center of the shielding partition plate 10 (evaporation position).
On the other hand, when the moving mechanism 8A moves to the rightmost side (heating position), the container 2A is positioned on the right side of the shielding partition plate 10, and the evaporated particles 30 from the container 2A reach the surface of the substrate 20 on the right side from the rotation center 22. It is like that. Further, the center of the container 2B is the same as the center of the shielding partition plate 10 (evaporation position).

  FIG. 3 shows a top view seen from the direction G of FIG. In FIG. 3, the center of the shielding partition plate 10 is deviated from the rotation center 22 and is located in the substrate 20 and in the vicinity of the edge of the substrate. Further, when the containers 2A and 2B are in the evaporation positions, the containers are positioned on the concentric circle C that is equidistant from the rotation center 22.

Next, a vapor deposition method using the electron beam vacuum vapor deposition apparatus 50 will be described. First, consider a case where the moving mechanism 8A is positioned as shown in FIG. In this state, the electron beam source 6 on the side of the container 2A is operated, and the electron beam 32 is ejected upward. The electron beam is deflected by 180 ° or 270 ° by a magnetic field circuit (not shown), and irradiates the evaporated substance from the opening 4A of the container 2A. The heating is performed until the vaporized particles are generated by heating above the temperature at which the evaporated substance is vaporized.
The operation timing of the electron beam source 6 is determined by, for example, detecting that the container 2A has come to a predetermined position with a sensor and operating the electron beam source, and measuring the deposition rate after a predetermined time (or measuring the deposition rate). In response, the electron beam source may be turned off.
Here, when the electron beam 32 is irradiated, secondary electrons, reflected electrons, or X-rays are emitted from the evaporated substance, and these adversely affect elements such as TFTs on the substrate in the process of forming the organic EL element. There is. Therefore, by arranging the shielding partition plate 10 above the irradiation area of the container 2A, secondary electrons and the like emitted from the upper surface of the container 2A are prevented from reaching the substrate 20. Further, the shielding partition plate 10 prevents the evaporated substance from reaching the substrate 20 in a state where the container 2A is positioned as shown in FIG.

When evaporation particles are generated from the container 2A by heating, the moving mechanism 8A slides to the right and moves the container 2A to the right side from the shielding partition plate 10. Then, the evaporated particles 30 generated by the residual heat of the evaporated substance in the container 2A jump out upward and are deposited on the substrate 20 facing the container 2A. The timing at which the moving mechanism 8 operates may be matched with the timing at which the electron beam source is turned off, for example.
In this way, when vapor deposition is performed on the substrate, only the residual heat is used without heating, so that X-rays or the like do not reach the substrate due to the electron beam irradiation used for heating.
Here, a quartz vibration deposition rate monitor (not shown) may be installed between the shielding partition plate 10 and the container 2A (when the container 2A is positioned on the right side of FIG. 1). And if heating time is lengthened and the vapor deposition rate immediately after heating is set high, the residual heat temperature becomes high, and the cooling of the evaporating substance during vapor deposition by moving the container 2A to the right side of FIG. 1 becomes slow. The time used for vapor deposition can be lengthened.
The present inventors actually formed a film using a vacuum deposition apparatus with a heating time of 2 seconds and a deposition time of 2 seconds. The deposition rate immediately after heating for 2 seconds is about 20 liters / sec (2 nm / sec), and when the container 2A is moved to the right side of FIG. It was confirmed to be 0 liter / sec.

While vapor deposition is performed using the container 2A, the container 2B is positioned below the shielding partition plate 10, and the evaporated substance in the container 2B is similarly heated. Then, when the vapor deposition by the container 2A is completed, the moving mechanism 8A slides to the left, and the container 2B moves to the left to be in the state of FIG. At this position, the evaporation substance in the container 2B jumps out due to residual heat, and the substrate 20 is deposited. At this time, the container 2A returns to the lower position of the shielding partition plate 10 and is again heated. Thereafter, by repeating this process and continuing the deposition, a predetermined deposition film thickness can be obtained. Note that the timing (corresponding to the vapor deposition time) at which the moving mechanism is operated after the vapor deposition by the container 2A is finished may be matched with the timing (corresponding to the heating time) at which the moving mechanism 8 is operated in the heating step, for example. For example, in the above-described actual example, the heating time and the vapor deposition time are the same (2 seconds).
As described above, for example, by using the container 2A after completion of heating, film formation is performed with residual heat until the vapor deposition rate becomes 0, and then vapor deposition is performed using the container 2B, whereby the containers 2A and 2B are alternately arranged. Can be continuously deposited.

  In this embodiment, the container 2A deposits the substrate portion on the right side of the rotation center 22, and the container 2B deposits the substrate portion on the left side of the rotation center 22. However, by rotating the substrate 20, the entire deposition surface of the substrate can be uniformly formed. For example, if the deposition is started from the position of FIG. 1 and the portion deposited by the container 2B rotates and reaches the position of the container 2A, the substrate is moved out of the system to uniformly deposit the entire surface of the substrate. become.

<Second Embodiment>
FIG. 4 is a perspective view showing an example of an electron beam vacuum evaporation apparatus according to the second embodiment of the present invention. Since the apparatus 50B according to this embodiment is exactly the same as the first embodiment except that there is one container, the same components as those of the first embodiment are denoted by the same reference numerals and the description thereof is omitted. .
In FIG. 4, a single container 2A is placed on the moving mechanism 8B. The moving mechanism 8B is a pedestal that can reciprocate on the track, and the moving mechanism 8B is controlled by a control unit (not shown).

  Next, a vapor deposition method using the electron beam vacuum vapor deposition apparatus 50A will be described. First, consider a case where the moving mechanism 8B has moved to the right as shown in FIG. At this position, the container 2 </ b> A is positioned below the shielding partition plate 10, and the evaporated substance in the container is heated by the electron beam 32 of the electron beam source 6. Heating is performed until evaporated particles are generated. X-rays and the like generated by irradiating the electron beam 32 are shielded by the shielding partition plate 10.

When evaporating particles are generated from the container 2A by heating, the moving mechanism 8B slides to the left and moves the container 2A to the left in FIG. Then, the evaporated particles 30 generated by the residual heat of the evaporated substance jump out upward and are deposited on the opposing substrate 20. Since heating is not performed when vapor deposition is performed on the substrate, X-rays or the like do not reach the substrate due to electron beam irradiation during heating.
In the case of the first embodiment, a quartz vibration deposition rate monitor (not shown) may be installed between the shielding partition plate 10 and the container 2A (when the container is on the right side in FIG. 4). It is the same.

  When vapor deposition by the container 2A is completed, the moving mechanism 8B slides to the right side, the container 2A returns to the lower side of the shielding partition plate 10, and heating is performed again. When heating is completed, vapor deposition is performed again. As described above, in the case of the second embodiment, the evaporation material is heated and vapor-deposited using the single container 2A. Therefore, the vaporization is paused while heating is performed. The film forming efficiency is low, but the apparatus is simple.

<Third Embodiment>
FIG. 5 is a perspective view showing an example of an electron beam vacuum deposition apparatus according to the third embodiment of the present invention. The apparatus 50C according to this embodiment is the same as that of the first embodiment except that the configuration of the moving mechanism is different. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.
In the third embodiment, the moving mechanism 8C is a disk-shaped rotary table, and the containers 2A and 2B are rotationally symmetrically arranged on the upper surface of the disk. Then, as shown in FIG. 5, with the container 2B positioned on the left side and the container 2A positioned on the right side, the shielding partition plate 10 is positioned above the container 2A, and the electron beam source 6 is adjacent to the container 2A. Further, the substrate 20 is disposed opposite to the upper side (opening 4B) of the container 2B.

  Next, a vapor deposition method using the electron beam vacuum vapor deposition apparatus 50C will be described. First, in the state shown in FIG. 5, the electron beam source 6 on the side of the container 2A is operated to irradiate the evaporated substance from the opening 4A of the container 2A. The heating is performed until the evaporated substance is heated to the melting temperature or the vaporization temperature or higher and evaporated particles are generated. As described above, secondary electrons and the like emitted from the upper surface of the container 2A are shielded by the shielding partition plate 10.

  When evaporating particles are generated from the container 2A by heating, the moving mechanism 8C rotates 180 ° to move the container 2A to the left side in FIG. 5 (the position of the container 2B in FIG. 5). Then, the evaporated particles 30 generated by the residual heat of the evaporated substance in the container 2A jump out upward and are deposited on the substrate 20 located on the container 2A. As in the above embodiments, a quartz vibration deposition rate monitor (not shown) may be installed between the shielding partition plate 10 and the container 2A (when the container 2A is located on the right side of FIG. 5). .

  Here, during vapor deposition by the container 2A, the container 2B is positioned below the shielding partition plate 10, and the evaporated substance in the container 2B is similarly heated. When the vapor deposition by the container 2A is completed, the moving mechanism 8 rotates 180 °, and the container 2B moves to the left side of FIG. At this time, the container 2A returns to the lower position of the shielding partition plate 10 and is again heated. Thereafter, by repeating this process and continuing the deposition, a predetermined deposition film thickness can be obtained. Also in this embodiment, by using a plurality of containers, the respective containers 2A and 2B can be alternately used for vapor deposition.

According to each of the above-described embodiments, it is possible to prevent elements such as TFTs on the substrate from being adversely affected by high energy particles such as secondary electrons and X-rays generated by irradiation of an electron beam when heating the evaporation substance. The
In addition, according to each of the above embodiments, the evaporation source is moved instead of the substrate, and therefore, an evaporation source having a relatively small size is a moving object. Therefore, the positional accuracy when moving the container to the heating position or vapor deposition position is increased, the moving speed can be made relatively fast, the film forming efficiency is improved by shortening the tact time, and the film forming distribution is uniform. (Reproducibility) can be improved. Therefore, it is possible to perform electron beam vacuum deposition with high yield and high productivity. In particular, this effect becomes significant when the substrate is large.

According to the above embodiment, when the substrate is small (200 mm square or less), uniform film formation is possible without rotating the substrate. In addition, with the increase in the size of the substrate, a current practical substrate of 200 mm square or more is used. In order to make the thickness distribution of the film formation uniform, the rotation film formation is mainly used. Therefore, when vapor-depositing on a large substrate, it is preferable to use the apparatus according to the first embodiment suitable for rotating film formation. Further, in the apparatus according to the first embodiment, the range in which the moving mechanism moves is almost the size of the evaporation source, which is desirable from the viewpoint of compactness of the apparatus, and the movement distance of the evaporation source is longer than that of the other embodiments. Short movement time can be achieved.
Furthermore, in each embodiment, a continuous film formation for a long time is possible by providing an evaporation substance supply mechanism. In addition, a crystal monitor can be installed in the vicinity of the substrate, and the film formation can be terminated when a desired film thickness is obtained.

In the above description of the first and third embodiments, two containers are used, but the number of containers is not limited to this. Further, the configuration of the moving mechanism is not limited to the cart or the rotary table.
Further, in order to suppress contamination of the filament that generates the electron beam in the heating mechanism, it is preferable that the deflection of the electron beam is 270 °.

It is a perspective view which shows an example of the electron beam vacuum evaporation system which concerns on the 1st Embodiment of this invention. It is a front view of FIG. FIG. 2 is a top view of FIG. 1. It is a perspective view which shows an example of the electron beam vacuum evaporation system which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows an example of the electron beam vacuum evaporation system which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

2A, 2B container 4A, 4B container opening 6 heating mechanism 8 moving mechanism 10 shielding partition plate 20 substrate 30 evaporative substance 32 electron beam 50 electron beam vacuum deposition apparatus

Claims (5)

A vacuum vapor deposition method for forming a vapor deposition substance contained in a container having an opening on a film formation target, wherein the container and the film formation target are disposed in a evacuated chamber,
The evaporating substance is irradiated with an electron beam at a first position where a shielding partition plate is interposed between the opening and the film forming object without an opening of the container facing the film forming object. Heating process for heating,
A film forming step of moving the container to a second position facing the film formation target, releasing the evaporated substance from the opening by residual heat, and forming a film on the film formation target;
A method of returning the container from the second position to the first position is repeated in this order. Comprising two or more of the containers,
While one film is moved to the second position and the film forming process is performed, another container is moved to the first position and the heating process is performed, and the film formation by the one container is completed. The electron beam vacuum deposition method according to claim 1, wherein the film forming step is continuously performed by moving the other container to the second position and performing the film forming step. 3. The electron beam vacuum deposition method according to claim 1, wherein in the heating step, an evaporating substance released from the container is shielded. A container containing an evaporating substance and having an opening;
A heating mechanism for generating an electron beam for heating the evaporating material;
A moving mechanism for moving the container;
A shielding partition plate,
Film-forming target, the container, the heating mechanism, the moving mechanism and the shielding partition plate is disposed in a vacuum evacuated chamber,
The heating mechanism is, the evaporating material the electron beam at a first position in which the shielding partition plate is interposed between the opening aperture of the container without facing the film-forming target and the film-forming target To evaporate and heat the evaporant,
The moving mechanism moves the container that has been heated at the first position to a second position that faces the film formation target, and releases the evaporating substance from the opening by residual heat to form a film. An electron beam vacuum deposition apparatus characterized by repeating the steps and a position returning step of returning the container after film formation to the first position in this order. Comprising two or more of the containers,
The moving mechanism moves the other container to the first position to perform the heating step while moving the one container to the second position and performs the film forming step, and the one container 5. The electron according to claim 4, wherein the film forming step is continuously performed by moving the other container to the second position and performing the film forming step when the film formation by the step is completed. Beam vacuum evaporation system.