JPH069014Y2 - Vacuum deposition equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a vacuum vapor deposition apparatus that supplies a plurality of types of vaporized substances to form a plurality of vapor deposition layers on the surface of an optical lens, for example. This is an improvement of the shutter mechanism for interrupting.

(Prior Art) In a conventional vacuum vapor deposition apparatus, it is known that a shutter is provided in the vicinity of an evaporation crucible to block the flight path of the evaporation material and interrupt the supply of the evaporation material. The shutter is used from the start of heating until a stable evaporation state is obtained, or when the vapor deposition film thickness reaches a predetermined value, etc. ing.

For example, in an optical lens, a plurality of kinds of vapor deposition substances may be alternately deposited in multiple layers on the surface, and even in such a case, the supply of each vaporization substance was controlled by one shutter in the same manner as above. .

(Problems to be Solved by the Invention) Normally, the shutter is formed of a stainless plate material or an aluminum plate material, but the coefficient of thermal expansion thereof is often different from the coefficient of thermal expansion of most evaporated substances. For this reason, the evaporated material attached to the shutter is likely to be peeled off due to the difference in thermal expansion, and in addition, the start-stop impact when switching the posture of the shutter frequently causes peeling.

The exfoliation of the vapor deposition mass attached to the shutter is not a problem. However, there is a problem in that the vapor-deposited mass is easily peeled off when the shutter is turned on and off, and the peeled pieces are easily dropped into the evaporation crucible. In particular, in a vacuum vapor deposition apparatus that supplies a plurality of types of vaporized substances, the stripping pieces contain various types of vaporized substances, and when these are re-evaporated, the purity of the vapor deposited film is impaired and the film quality is impaired. It will end up. Depending on the amount of the peeled pieces, the vapor deposition film may not function normally.

Further, when a plurality of types of vaporized substances are alternately deposited in multiple layers, it takes a long time to form a film, a large amount of vaporized substances are attached to the shutter during that time, and the vapor deposition mass alternates between heating and cooling. Since it is received many times, peeling is likely to occur during film formation, and the continuous operation time of the vacuum vapor deposition apparatus is limited because it is necessary to avoid the mixing of peeling pieces as described above. Furthermore, the shutter must be cleaned at relatively short time intervals, which is disadvantageous in that maintenance work is troublesome.

This invention has been proposed in view of the above, and by preventing the vapor deposition lump adhering to the shutter from peeling off, the vapor deposition lump is prevented from falling into the evaporation crucible, and the vapor deposition film quality can be maintained at a high quality. The purpose is to

Another object of the present invention is to realize continuous extension of the vacuum vapor deposition apparatus operation time and extension of the shutter cleaning interval by preventing the vapor deposition lumps from peeling, thus improving the productivity of the film forming process as a whole. To improve.

(Means for Solving the Problems) In the present invention, a plurality of shutters for blocking evaporative substances are provided, and these shutters are selectively used for different evaporative substances to control the supply of the evaporative substances. Further, the material for forming the shielding wall of each shutter plate is formed of a material having a coefficient of thermal expansion similar to that of the corresponding evaporation substance to prevent the vapor deposition lump from peeling.

Specifically, it is provided corresponding to a plurality of types of evaporated substances,
The shutter mechanism is composed of a plurality of individually operable shutters, and each shutter has a shutter plate that blocks the flight path of the vaporized substance. It is formed of a material having a coefficient of thermal expansion that is the same or similar.

(Function) For example, when three shutters are provided corresponding to three kinds of evaporated substances, each shutter can be used as a dedicated shutter for the corresponding evaporated substances, and therefore, adheres to each shutter plate in a series of film forming steps. The amount of vapor deposition mass can be reduced. Further, since the coefficient of thermal expansion of each evaporative substance and the material forming the shielding wall of the shutter plate corresponding to each evaporative substance are matched or approximated to each other, the difference in thermal expansion between the individual shutter plates can be eliminated or suppressed, and As a result, the exfoliation of the vapor deposition lump can be effectively prevented.

(First Embodiment) FIGS. 1 and 2 show an embodiment in which the present invention is applied to an electron beam type vacuum vapor deposition apparatus.

In FIG. 1, the vacuum vapor deposition apparatus irradiates and supplies a substrate holder 4 holding a large number of vapor deposition targets 3 into a vacuum chamber 2 partitioned by a partition wall 1, and an evaporated substance toward the substrate holder 4. An electron beam evaporation source 5 and a shutter mechanism 6 for controlling the supply of the evaporation source are arranged.

The substrate holder 4 is formed in a dome shape and is rotationally driven by a drive device 11 mounted on the ceiling wall of the partition wall 1. The evaporation target 3 is attached to the inner surface of the substrate holder 4 so as to face the evaporation source 5. The vapor deposition target 3 is an optical glass such as an optical lens or a reflecting mirror, or a semiconductor substrate, and vapor deposition films are formed in multiple layers on the surface thereof. In the case where the substrate holder 4 is turned upside down to form a vapor deposition film on the front and back of the vapor deposition target 3, the vapor deposition film does not necessarily have to be multilayer.

The evaporation source 5 is configured to be capable of individually evaporating and supplying a plurality of kinds of evaporation substances. More specifically, a turntable-shaped evaporation crucible 8 is provided adjacent to the electron gun 7, and a plurality (six in the figure) of crucible holes 9 are formed on the upper surface of the evaporation crucible 8. It is housed. Further, the whole evaporation crucible 8 is rotatably supported by a bearing 10, and this can be rotatably operated by a driving device 11 provided on the outer surface of the partition wall 1, and an arbitrary crucible hole 9 is positioned at a beam irradiation position of the electron gun 7. I am allowed to do it. Irradiation target crucible hole 9
The upper surface of the evaporation crucible 8 is covered with a cover 12 in order to prevent the evaporation material from being mixed into the evaporation crucible 8. As shown in FIG. 2, a trapezoidal notch 13 is formed on the plate surface of the cover 12 in correspondence with the beam irradiation position of the electron gun 7. It should be noted that three crucible holes 9 each contain three kinds of evaporation substances, two at a time in the stacking order. That is, the same vapor deposition material is accommodated in the pair of crucible holes 9 that are opposed to each other in the radial direction.

In FIG. 2, the shutter mechanism 6 is composed of three individually operable shutters 15. Three shutters 15
Are formed in the same structure and are arranged at equal angular intervals around the crucible hole 9 to be irradiated. As shown in FIG. 1, each shutter 15 has a partition wall 1.
A shutter shaft 16 that vertically penetrates the shutter shaft 16; a rotary actuator 17 that rotates the shaft 16 in forward and reverse directions; and a shutter plate 19 that is rotatably mounted on the shutter shaft 16 via an arm 18 and the like. There is. The shutter plate 19 is formed in the shape of a round tray, and is fixed to the arm 18 with screws 21 with the opening surface facing downward. Shutter plate 19
One of the screw holes formed in the arm 18 is formed as an elongated hole 22 in order to release the thermal strain of (1).

When the rotary actuator 17 is driven, the shutter plate 19 rotates horizontally along with the shutter shaft 16, and the shielding wall 20 on the inner surface of the shutter plate 19 blocks the entire flight path of the vaporized substance, and the shutter plate 19 is rotated. Is switched to a standby posture in which the entire body of the vehicle is completely retracted from the flight path. Each of the shutters 15 described above is provided corresponding to three kinds of vapor deposition materials, and each of them is used only to control the supply of the same kind of vaporization material.

As described above, the shutters 15 have the same structure, but the shutter plates 19 are made of different materials. That is, each shutter plate 19 is formed of a material having a coefficient of thermal expansion that matches or approximates the coefficient of thermal expansion of the corresponding evaporated substance. For example, the evaporation material is Al ₂ O ₃ (5 to 7 × 10 ⁻⁶ / ° C. or less, the value in parentheses indicates the coefficient of thermal expansion), ZnS (6 × 10 ⁻⁶ / ° C.),
In the case of ZrO ₂ (6 × 10 ⁻⁶ / ° C.), the shutter plate 1
9 is Hastelloy A (3 × 10 ⁻⁶ / ° C. Mo20, Fe
20, including Ni60). Further, the vaporized substances are Cr (7 × 10 ⁻⁶ / ° C.) and CeF ₃ (11.5 × 10 ⁶ ).
^In the case of ⁻⁶ / ° C.), the shutter plate 19 is made of chrome stainless steel (11 × 10 ⁻⁶ / ° C.). In addition, the evaporated substances are Au (14 × 10 ⁻⁶ / ° C.) and Ag (19 × 10 ^−6).
/ ° C.), the shutter plate 19 is made of 18-8 stainless steel (17 × 10 ⁻⁶ / ° C.). The shutter plate 19
Other materials used for the amber (1.2 × 10 ^-6
/ ° C. Fe64 and Ni36 are included), aluminum (23 × 10 ⁻⁶ / ° C.), fused silica (0.55 × 10
^-6 / ° C) and the like.

Next, a usage mode of each shutter 15 will be described.

When forming the vapor deposition film of the first layer, the predetermined crucible hole 9 is positioned at the irradiation position of the electron gun 7, and the shutter plate 19 corresponding to the vapor deposition substance accommodated in the crucible hole 9 is further provided.
Evaporation is started in the state where it is switched to the use posture. Then, after the evaporation state is stabilized, the shutter plate 19 is returned to the standby posture, and film formation is performed until a predetermined film thickness is obtained.

When the film thickness reaches a predetermined value, the shutter plate 15 is switched to the use posture again, the beam oscillation of the electron gun 7 is stopped at the same time, and the evaporation crucible 8 is rotated to contain the evaporation material of the second layer. The crucible hole 9 is located at the irradiation position.

In this state, the shutter plate 19 for the first layer is returned to the standby position, and the shutter plate 19 corresponding to the vapor deposition material of the second layer is switched to the use position. Next, the electron gun 7 is restarted, and after the evaporated substance is stabilized, the shutter plate 19 is returned to the standby posture, and film formation is continued until a predetermined film thickness is obtained.

When the third layer is formed, the crucible hole 9 is selected and the shutter plate 19 is replaced in the same manner as described above to form the film.

As described above, the shutter plate 19 is provided for each vapor deposition material.
If the supply control is performed in step (1), it is possible to reduce the amount of vapor deposition adhered to each shutter plate 19 in a series of film forming steps, and to extend the time until peeling starts. Further, when each vapor deposition substance is vaporized, the supply control is performed by the shutter plate 19 dedicated thereto, so that the vapor deposition mass does not contain vapor deposition substances of different types, and even if the peeling pieces fall into the crucible hole 9, Even if there is, it is possible to prevent the quality of the deposited film from being impaired.

Further, by forming the shutter plate 19 with a material having a thermal expansion coefficient substantially equal to that of each vapor deposition material, the shutter plate 1
It is possible to prevent the peeling of the vapor deposition lump 9 and the vapor deposition lump attached thereto due to the difference in thermal expansion, and to prevent the peeling of the vapor deposition lump for a long period of time in combination with the reduction of the amount of the vapor deposition lump attached.

Second Example An interference coating layer that blocks the entry of ambient light or ultraviolet light was formed on the surface of the optical lens (deposition target) 3 by the same vacuum vapor deposition apparatus as in the first example. In this case, seven layers of magnesium fluoride and zinc sulfide, which are metal compounds having different adhesion ratios, were alternately deposited to form an interference coating layer. In this case, since the formed film exhibits anisotropy in the expansion coefficient and is not constant, the shutter plate 19 made of a material having a coefficient of thermal expansion that is the same as or close to that of the film at that time is appropriately selected. I am using it.

(Modification) Although the shutter plate 19 is entirely made of a predetermined material in the above embodiment, it is not always necessary. For example, the shutter plate 19 may be formed of a metal or a refractory material, a predetermined material may be fixed to the inner surface of the shutter plate 19 by plating, thermal spraying, casting, or the like, and only the shielding wall 20 may be formed of a predetermined material corresponding to each vapor deposition material. .

Any number of shutters 15 may be provided as long as they are two or more. When the number of installed shutters 15 is large, the shutter 15 can be easily moved up and down by shifting the closing height position of the shutter plate 19 without increasing the cross-sectional area of the vacuum chamber 2.
Can be installed.

The shutter 15 and the vapor deposition material do not necessarily have to have a one-to-one correspondence. For example, it is possible to control the supply of two kinds of vapor deposition substances having similar thermal expansion coefficients with a single shutter.

The present invention can be applied to various vacuum vapor deposition devices regardless of the structure of the substrate holder 4 and the driving mode thereof. For example, it can be widely applied to a vacuum vapor deposition apparatus provided with a planetary type or a reversal type substrate holder.

(Effects of the Invention) As described above, in the present invention, the shutter mechanism is composed of a plurality of individually operable shutters, and the shutter is selectively used according to the difference in the vapor deposition material to reduce the deposition amount of vapor deposition lumps on the shutter plate. I made it possible. Further, the shielding wall of the shutter plate in each shutter is formed of a material having a coefficient of thermal expansion that is the same as or similar to that of the corresponding vapor deposition material, so that peeling due to the difference in thermal expansion can be eliminated.

Therefore, according to the vacuum vapor deposition apparatus of the present invention, it is possible to prevent the vapor deposition lump from peeling off for a long period of time, so that it is possible to prevent the vapor deposition lump from falling into the evaporation crucible at the time of film formation and to reduce the film quality. The film quality can be maintained at a high level. In addition, the time until the vapor deposition mass begins to peel off can be significantly extended compared to the conventional device, so that the continuous operation time of the vacuum vapor deposition device can be extended, and the cleaning interval of the shutter plate can be extended. As a result, it is possible to improve the operation rate of the vacuum vapor deposition apparatus and improve its productivity.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention, FIG. 1 is a vertical sectional view showing a schematic structure of a vacuum vapor deposition apparatus, and FIG.
It is the sectional view on the AA line in a figure. 2 ... Vacuum chamber, 3 ... Target of vapor deposition, 5 ... Vapor deposition source, 6 ...
Shutter mechanism, 15 ... Shutter, 19 ... Shutter plate, 20 ... Blocking wall.

Claims (1)

[Scope of utility model registration request] 1. A vacuum vapor deposition apparatus comprising: an evaporation source for individually vaporizing and supplying a plurality of types of vapor deposition substances; and a shutter mechanism for interrupting the flight path of the vaporization substances and controlling the supply of the vaporization substances only when necessary. Therefore, the shutter mechanism is composed of a plurality of individually operable shutters that are provided for multiple types of vaporized substances, and each shutter has a shutter plate that blocks the flight path of the vaporized substances. The vacuum evaporation apparatus, wherein the shielding wall is formed of a material having a coefficient of thermal expansion that matches or approximates the coefficient of thermal expansion of the corresponding evaporated substance.