JP2014070243A - Sensor head for quartz oscillation type film thickness monitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor head for a quartz oscillation type film thickness monitor, which can perform a film thickness measurement stable for a long time period so that it can extend a continuous operation time period of an organic EL manufacturing apparatus.SOLUTION: A sensor head for a quartz oscillation type film thickness monitor comprises: a quartz oscillator for detecting evaporation particles from a heated crucible; a quartz oscillator holder 10 having the quartz oscillator attached thereto; a metallic cover 17 for covering the quartz oscillator holder; a monitor body connected thermally to the cover; and a cooling member attached to the monitor body. The sensor head is characterized in that the cover is made of stainless steel 17a at its portion near a heat source and an aluminum alloy 17b at its portion to contact the monitor body.

Description

  The present invention relates to a crystal oscillation type film thickness monitor sensor head.

  As a thin film thickness detection method in an organic EL manufacturing apparatus or the like, there is a crystal oscillation type. This crystal oscillation type measures the film thickness of the substance by utilizing the fact that the resonance vibration changes when the substance adheres to the surface of the crystal resonator.

  In this case, when the crystal unit is affected by heat generated during vapor deposition, the resonance frequency of the crystal unit fluctuates, making accurate measurement impossible and affecting the film formation result.

  As a conventional technique for solving this problem, for example, there is Patent Document 1. In this prior art, the temperature of a monitor made of a crystal resonator is held at a predetermined constant temperature by a Peltier element.

JP-A-63-72872

  The conventional crystal oscillation film thickness monitor sensor head is equipped with a water cooling coil (cooling mechanism) as a heat countermeasure, and a heat shield (heat shield cover) is attached so as to cover the crystal unit. The quartz crystal was protected from.

  The crystal unit holder that houses the heat shield and the crystal unit is made of a low heat conductive material such as stainless steel.

  However, in recent years, it has been required to extend the continuous operation time of the apparatus, and as a result, the time during which the crystal unit is exposed to radiant heat has also become longer, and stronger heat protection is required.

  Further, when the crystal unit holder is cooled as a heat countermeasure, a phenomenon called heat shock occurs due to a temperature difference between the unused state and the time of vapor deposition, which adversely affects the film thickness measurement.

  Japanese Patent Laid-Open No. 2004-228561 prevents the crystal resonator from rising by means of surrounding the crystal resonator monitor with a Peltier element. However, there is a problem that the configuration becomes complicated.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a crystal oscillation type film thickness monitoring sensor head that enables stable film thickness measurement over a long period of time and can extend the continuous operation time of an organic EL manufacturing apparatus.

  In order to solve the above-described problems, the present invention provides a quartz resonator that detects evaporated particles from a heated crucible, a quartz resonator holder to which the quartz resonator is attached, and a metal that covers the quartz resonator holder. A cover, a monitor body thermally connected to the cover, and a cooling member attached to the monitor body, wherein the cover is made of stainless steel at a portion close to a heat source, and a portion in contact with the monitor body It is an aluminum alloy.

  According to the present invention, it is possible to provide a sensor head for a crystal oscillation type film thickness monitor that enables stable film thickness measurement over a long period of time and can extend the continuous operation time of the organic EL manufacturing apparatus.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is a disassembled perspective view of the evaporation source apparatus which concerns on the Example of this invention. It is sectional drawing of the thin film forming apparatus provided with the evaporation source apparatus which concerns on the Example of this invention. It is a perspective view of the evaporation source device concerning Example 1 of the present invention. It is a front view of the crystal resonator based on Example 1 of this invention. It is a perspective view of the film thickness control apparatus which concerns on Example 1 of this invention. It is a perspective view containing the partial cross section of the film thickness control apparatus which concerns on Example 1 of this invention. It is sectional drawing of the film thickness control apparatus which concerns on Example 1 of this invention. It is a fragmentary sectional view of the film thickness control apparatus concerning Example 2 of the present invention. It is a fragmentary sectional view of the film thickness control apparatus concerning Example 2 of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  Hereinafter, embodiments of the organic EL device manufacturing apparatus of the present invention will be described with reference to FIGS.

  The organic EL device device has a multilayer structure in which various materials such as a hole injection layer, a transport layer, an electron injection layer, a transport layer, and a metal material are stacked in a thin film in addition to a light emitting material layer.

  FIG. 1 is an exploded perspective view of an evaporation source apparatus according to an embodiment of the present invention.

  FIG. 2 is a cross-sectional view of a thin film forming apparatus provided with an evaporation source apparatus according to an embodiment of the present invention.

  1 and 2, an EL material evaporation source device 1 includes a casing 2 (water-cooled shield box) that extends long in one horizontal direction, and a crucible 4 in which the EL material 3 is stored. Is stored in the direction of the arrow. A heating device 5 (heater) for heating the crucible 4 at a predetermined temperature is attached around the crucible 4 as shown in FIG.

  A gas discharge plate 6 is attached to the front surface of the crucible 4. The gas discharge plate 6 has a plurality of gas discharge holes 6a formed uniformly in the horizontal direction. The gas discharge hole 6a is formed such that the distance between both ends is closer than the distance at the center.

  In FIG. 2, the evaporation source device 1 is accommodated in a vacuum chamber 7 indicated by a dotted line. In the vacuum chamber 7, a deposition target substrate 8 such as a glass plate for manufacturing an organic EL device is fixed upright by a holding device (not shown). The evaporation source apparatus 1 moves up and down with respect to the deposition target substrate 8 as indicated by an arrow. The evaporation source device 1 is configured to inject the vaporized particles 3a of the organic EL material 3 in a gaseous state by heating by the heating device 5 from the gas discharge hole 6a while moving up and down. As a result, the evaporated particles 3 a of the organic EL material 3 are widely deposited on the surface of the deposition target substrate 8.

  FIG. 3 is a perspective view of the evaporation source apparatus according to Embodiment 1 of the present invention. FIG. 3 is drawn with the gas release plate removed for convenience of explanation.

  In FIG. 3, as mentioned above, the crucible 4 is attached in the housing | casing 2 provided with the cooling mechanism (not shown). At both ends of the crucible 4, a film thickness control device 9 (also referred to as a film thickness sensor) having a crystal resonator for controlling the film thickness is installed.

  As described above, the film thickness control device 9 is always exposed to a high temperature by the evaporated particles 3a ejected from the crucible 4 heated to a predetermined temperature by the heating device 5.

  Here, the structure of the crucible 4 will be described. The crucible 4 has an organic EL material 3 to be deposited inside, and a stable deposition rate can be obtained by controlling the heating with the heating device 5. A plurality of gas discharge holes 6a are arranged in front of the crucible 4, and the vaporized particles 3a evaporated by heating are ejected from the gas discharge holes 6a.

  Next, the configuration of a film thickness control apparatus having a crystal resonator for performing film thickness control used in this embodiment will be described with reference to FIGS. 4, 5, and 6.

  FIG. 4 is a front view of the crystal resonator according to the embodiment of the present invention.

  In FIG. 4, twelve crystal resonators 11 having a diameter of about 20 mm are mounted on a disk-shaped crystal resonator holder 10 in a ring shape. The crystal unit holder 10 includes a mechanism for electrically controlling the crystal unit 11. The film thickness control by the crystal unit 11 is to detect the thickness of the metal film attached to the deposition target substrate 8 by utilizing the fact that the oscillation frequency is lowered when the metal film is attached to the crystal unit 11.

  Therefore, as described above, the crystal unit 11 is always exposed to a high temperature by the evaporated particles 3a ejected from the crucible 4 heated to a predetermined temperature by the heating device 5.

  FIG. 5 is a perspective view including a partial cross section of the film thickness control apparatus according to the embodiment of the present invention.

  In FIG. 5, the circular crystal resonator holder 10 constituting the crystal oscillation type film thickness monitoring sensor head is inclined (inclination angle θ) toward the center so that the center of rotation is lowered. A plurality of recesses 12 are formed on the inclined surface at equal intervals on the circumference. A crystal resonator 11 having a disk-like outer shape is inserted into the recess 12. In this embodiment, as shown in FIG. 4, twelve crystal resonators 11 are attached in a ring shape.

  A pressing plate 14 having an opening 13 having a ring-like conical concave surface is attached from above the plurality of crystal resonators 11. An electrode 15 is formed on the surface of the crystal unit 11. The lower part of the crystal unit holder 10 is electrically guided to the outside of the header part via a pair of contact electrode plates 16.

  Therefore, as described above, the crystal unit 11 is always exposed to a high temperature via the pressing plate 14 by the evaporated particles 3a ejected from the crucible 4 heated to a predetermined temperature by the heating device 5.

  Although not shown in the figure, electrodes made of, for example, a leaf spring are attached to the recess 12 and the pressing plate 14 of the crystal resonator holder 10.

  FIG. 6 is a perspective view including a partial cross section of the film thickness control apparatus according to the embodiment of the present invention.

  In FIG. 6, the crystal unit holder 10 to which the crystal unit 11 is attached is covered with a cover 17. The cover 17 has an inclined surface that coincides with the inclined surface on which the crystal unit 11 is disposed, and a supply hole 18 having a size that matches the diameter of the crystal unit 11 is provided on the inclined surface.

  A rotation shaft 20 is attached to the center of the crystal unit holder 10. The rotating shaft 20 passes through the monitor main body 22 below the crystal unit holder 10. A cooling pipe 23 is thermally connected to the monitor body 22. The cooling pipe 23 is a cooling jacket of a so-called water cooling device that circulates cooling water.

  Therefore, as described above, the crystal unit 11 is always exposed to a high temperature via the cover 17 and the pressing plate 14 by the evaporated particles 3a ejected from the crucible 4 heated to a predetermined temperature by the heating device 5. .

  FIG. 7 is a cross-sectional view of a film thickness control apparatus according to an embodiment of the present invention.

  In FIG. 7, the crystal unit holder 10 into which the crystal unit 11 is fitted is covered with a cover 17. The cover 17 is made of two kinds of metals, the upper part being made of stainless steel 17a and the lower part being made of an aluminum alloy 17b.

  That is, as shown in FIG. 7, the portion of the cover 17 exposed to the highest temperature is the stainless steel 17a, and the stainless steel 17a is continuous with the aluminum alloy 17b.

  Therefore, heat is accumulated in the stainless steel 17a, and the accumulated heat is gradually moved to the aluminum alloy 17b and spread. On the other hand, since the aluminum alloy 17b is in contact with the monitor main body 22 cooled by the water cooling pipe 23, it is gradually cooled. Thereby, the heat accumulated in the stainless steel 17a is removed through the aluminum alloy 17b, so that the crystal resonator can be protected from heat for a long time.

  That is, in the present invention, the conventional cover 17 is formed only of stainless steel, and in the present invention, a partial aluminum alloy area is provided in the stainless steel. Accordingly, the aluminum alloy and the monitor main body are brought into contact with each other in order to avoid excessive cooling of the crystal resonator by the monitor main body while accumulating heat to some extent with stainless steel. That is, in the aluminum alloy area, the temperature as close to room temperature as possible is stably maintained for a long time to cool.

  As described above, according to the present embodiment, the heat shield and the crystal unit holder have a structure in which stainless steel, which is a low heat conductive material, and aluminum alloy, which is a high heat conductive material, are combined, so that the heat accumulated in the stainless steel is aluminum. By removing it through the alloy, the crystal resonator can be protected for a long time.

  FIG. 8 is a partial cross-sectional view of a film thickness control apparatus according to Embodiment 2 of the present invention.

  In FIG. 8, a claw portion 17c is provided at the tip of the stainless steel 17a. A groove portion 17d into which a claw portion 17c of stainless steel 17a is inserted is provided at the tip of the aluminum alloy 17b.

  That is, the cover 17 made of different materials can be integrally formed by inserting the claw portion 17c of the stainless steel 17a into the groove portion 17d of the aluminum alloy 17b. If further strength is added to the present embodiment, a screw 17e penetrating the claw portion 17c and the groove portion 17d may be provided as shown in FIG.

  FIG. 9 is a partial sectional view of a film thickness control apparatus according to the second embodiment of the present invention.

  In FIG. 9, the cover 17 is formed of stainless steel and an aluminum alloy in the first embodiment, but in this embodiment, the crystal unit holder 10 is formed of the stainless steel 10a and the aluminum alloy 10b.

  As described above, according to the present invention, the heat from the evaporation source device once accumulated in the stainless steel is indirectly removed through the aluminum alloy that comes into contact with the monitor main body cooled by the water cooling jacket. Therefore, since the quartz resonator is made of an aluminum alloy, it is protected for a long time at a temperature close to room temperature, so that a heat shock due to a temperature difference due to excessive cooling can be prevented.

1 ... evaporation source device, 2 ... housing,
3 ... EL material, 3a ... evaporated particles,
4 ... crucible, 5 ... heating device,
6 ... Gas release plate, 6a ... Gas release hole,
7 ... Vacuum chamber, 8 ... Deposition substrate,
9 ... Film thickness control device, 10 ... Quartz crystal resonator holder,
10a ... stainless steel, 10b ... aluminum alloy,
11 ... quartz crystal, 12 ... recess,
13 ... opening, 14 ... pressing plate,
15 ... Electrode, 16 ... Contact electrode,
17 ... cover, 17a ... stainless steel,
17b ... Aluminum alloy, 17c ... Claw part,
17d ... groove, 17e ... screw,
18 ... supply hole, 20 ... rotating shaft,
22 ... Monitor body, 23 ... Cooling piping.

Claims (5)

A quartz resonator that detects evaporated particles from a heated crucible;
A crystal unit holder to which the crystal unit is attached;
A metal cover that covers the crystal unit holder;
A monitor body thermally connected to the cover;
A cooling member attached to the monitor body,
A quartz oscillation type film thickness monitor sensor head characterized in that the cover is made of stainless steel at a portion close to a heat source and an aluminum alloy at a portion in contact with the monitor main body. In the crystal oscillation type film thickness monitor sensor head according to claim 1,
A quartz oscillation type film thickness monitor sensor head, wherein the cover is formed by integral molding of stainless steel and aluminum alloy. In the crystal oscillation type film thickness monitor sensor head according to claim 1,
While providing a claw at the tip of the stainless steel, providing a groove at the tip of the aluminum alloy,
A quartz oscillation type film thickness monitor sensor head, wherein the cover is formed by inserting the claw into the groove. In the crystal oscillation type film thickness monitor sensor head according to claim 3,
A sensor head for a crystal oscillation type film thickness monitor, wherein the stainless steel and an aluminum alloy are coupled with screws. In the crystal oscillation type film thickness monitor sensor head according to claim 3,
A crystal oscillation type film thickness monitor sensor head characterized in that the crystal unit holder has a two-layer structure of stainless steel and aluminum alloy.

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