JP2009001885A - Film thickness detection apparatus and vapor deposition method - Google Patents

Abstract

The operating efficiency of a vapor deposition apparatus is improved by regenerating a vibrator of a film thickness detection apparatus in the vapor deposition chamber in the vapor deposition chamber.
A plurality of vibrators 5 are installed in a vibrator holder 4. When a vapor deposition film having a certain thickness is deposited on the surface of the vibrator 5 whose film thickness is to be measured at the operation position A, the heater block 8 can be heated and the surrounding area is covered with the cooled wall surface of the shield 1. The vibrator 5 is moved to the position B, and the vapor deposition film on the vibrator surface is detached and reproduced. During this time, at the operating position A, the measurement of the film thickness is continued using another vibrator 5. By repeating this process, it becomes possible to continue vapor deposition for a long time without opening the vapor deposition chamber to the atmosphere.
[Selection] Figure 1

Description

  The present invention relates to a film thickness detection apparatus and a vapor deposition method used in a vapor deposition apparatus that deposits a thin film on a deposition target substrate.

  Organic EL display devices can achieve high brightness and low power consumption, and are characterized by thinness, high-speed response, and high viewing angles as display devices that replace liquid crystal display devices, and are attracting attention as trends in future display devices. There are roughly two methods for manufacturing an organic EL display device. One is a method of forming a low molecular weight organic EL material by mask vapor deposition, and the other is a method in which a rib is previously formed on a substrate, and then a polymer organic EL is formed in a recess surrounded by the rib by an inkjet method or the like. It is a method of supplying a material. Among these, the method of supplying a polymer organic EL material by an ink jet method or the like is still in the process of developing a polymer organic EL material to be used, and commercialization has not been realized at this stage. On the other hand, a method using a vapor deposition method has already been commercialized in a passive matrix monocolor and area color panel.

  In the case of a conventional organic EL film material vapor deposition apparatus in the case of small-scale production (badge type), it is repeated that the deposition target substrate (substrate) and the vapor deposition material for one vapor deposition are reaccommodated for each film formation. However, when mass production is performed, several to several hundred deposition materials are stored in advance in a crucible of a deposition chamber that is permanently installed in the deposition chamber, the deposition chamber holds a vacuum, and a load lock chamber is provided only for the substrate. It is exchanged for every vapor deposition.

  When mass production of thin films for organic EL is performed, it is possible to deposit a thin film on a large number of substrates by accommodating the vapor deposition material in a large-capacity crucible. You can replace it. However, when measuring the deposition rate and film thickness during deposition, the crystal oscillator (vibrator) is fixed in the vicinity of the substrate. This is generally done by measuring fluctuations. The fluctuation of the frequency with respect to the change in the weight of the vibrator has a substantially linear relationship. However, when the deposited film on the vibrator reaches a certain weight, the change in the weight and the fluctuation in the frequency become irregular and accurate. Loses sex. For this reason, a countermeasure is used in which a plurality of vibrators are arranged circumferentially on a rotatable vibrator holder, and when a certain amount of deposited film adheres to the vibrator, the vibrator holder is rotated and sequentially replaced with new vibrators. ing. This configuration is employed in Infineon's Crystal 12 Sensor disclosed in Non-Patent Document 1.

Inficon Technical Note Thin Film Deposition Controllers and Monitors B4.13

  However, in the conventional technology, the maximum number of vibrators that can be installed is about ten or so at maximum. Considering mass production of thin films, the lifetime of the vibrator is small compared to a deposition source equipped with a substrate or a large-capacity crucible that can be put in an unlimited number through the load lock chamber. This indicates that the maintenance cycle of the vibrator controls the maintenance cycle of the entire vapor deposition system in mass production of thin films for organic EL.

  An object of this invention is to provide the film thickness detection apparatus and vapor deposition method which can improve the operating efficiency of a vapor deposition apparatus significantly by performing the maintenance of a vibrator | oscillator during vapor deposition.

  The film thickness detection apparatus of the present invention is disposed in the vapor deposition chamber in the film thickness detection apparatus that detects the film thickness of the thin film deposited on the vapor deposition substrate in the vapor deposition chamber by measuring the weight change of the vibrator. A plurality of vibrators, a moving means for moving the plurality of vibrators between an operating position and a non-operating position in the deposition chamber, and a vapor deposition material attached to each vibrator at the non-operating position. And a driving means for detecting the film thickness of the thin film by vibrating each vibrator at the operating position.

  The vapor deposition method of the present invention is a vapor deposition method in which a vapor deposition material is vaporized in a vapor deposition chamber and a thin film is vapor deposited on the vapor deposition substrate, and by measuring a weight change of a vibrator disposed in the vapor deposition chamber, A measuring step for detecting the film thickness of the thin film deposited on the substrate, and a regeneration step for desorbing the deposition material attached to the vibrator by a regeneration means disposed in the deposition chamber, The measurement process and the regeneration process are alternately performed.

  The vibrator can be regenerated without exposing the vapor deposition chamber to the atmosphere, and the measurement can be continued using another vibrator while the vibrator is being regenerated, so that the film thickness measurement can be continued semipermanently. During this time, the substrate to be deposited is carried in and out through the load lock chamber, and the vapor deposition material can be operated continuously for a long time, which has been impossible until now, by using a large-capacity deposition source.

  The best mode for carrying out the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the shield 1 is disposed so as to face the vapor flow for forming the thin film. The shield 1 includes a pipe 2 through which cooling water flows in order to keep the surface below the boiling point of the vapor deposition material, and an opening 3 through which a vapor flow passes. A vibrator holder (moving means) 4 disposed facing the surface of the shield 1 holds a plurality of vibrators 5. By rotating the vibrator holder 4 by the drive system 6, each vibrator 5 is sequentially moved to the operating position A and the non-operating position B facing the opening 3.

  At the operating position A, the vibrator 5 is connected to the connection terminal 7 which is an electrical connecting means for detecting the film thickness, and at the non-operating position B, the heater block 7 (heating means) 8 constituting the reproducing means together with the shield 1 is used. The reproduction of the vibrator 5 is performed.

  As described above, the film thickness detection apparatus of FIG. 1 has the vibrator holder 4 that can hold a plurality of vibrators 5 and can move the vibrators 5 alternately to the operating position A and the inoperative position B in the deposition chamber. The vibrator holder 4 is alternately moved to a non-operation position B where the vibrator 5 can be regenerated by heating and an operation position A for measuring the deposition rate. In the inoperative position B, a heater block 8 that heats and regenerates the vibrator 5 and a shield 1 that covers the surface of the vibrator 5 with a cooled wall surface are disposed.

  In this embodiment, the vibrator can be regenerated and reused by detaching the vapor deposition material attached to the surface of the vibrator from the surface of the vibrator. In addition, while a plurality of vibrators are mounted and one vibrator is heated and reproduced, measurement is performed using another vibrator. At this time, it is necessary to always perform the measurement at the same position so that the measurement value does not fluctuate.

  A plurality of vibrators are arranged in a rotatable vibrator holder, and the vibrators alternate between an operating position as a measurement position and a non-operating position for heating regeneration by the rotational movement of the vibrator holder. For this reason, measurement of the film thickness and reproduction of the vibrator can be performed simultaneously.

  Also, during the heating regeneration of the vibrator, the surface of the vibrator is exposed in a shield enclosure that is kept below the boiling point of the vapor deposition material in vacuum, and the vapor deposition material detached from the vibrator is placed on the wall of the shield. Capturing prevents deposition space contamination.

  1 and 2 show a film thickness detection apparatus (film thickness sensor) 100 according to Example 1, and FIG. 3 shows a vapor deposition apparatus using the film thickness detection apparatus 100. FIG. The shield 1 is supported by a structure not shown, and cooling water circulates in the internal pipe 2. A measurement opening 3 is disposed at the measurement site of the vibrator 5, and a vapor flow of the vapor deposition material passes through the opening 3 and adheres to the surface of the measurement vibrator 5. A plurality of the vibrators 5 are installed in the vibrator holder 4, and the vibrator 5 at the operation position A for measurement comes into contact with the connection terminal 7 from the back surface and is electrically connected to an oscillator which is a driving means (not shown). Connected to. In addition, the vibrator 5 that is not involved in the measurement is brought into contact with or close to the heater block 8 from the back side of the vibrator 5 at the inoperative position B, and is heated to a temperature equal to or higher than the boiling point of the vapor deposition material in vacuum. The vibrator holder 4 is supported by a drive system 6 that can rotate and move back and forth. The connection terminal 7 and the heater block 8 are supported by a structure not shown.

  In the vapor deposition apparatus shown in FIG. 3, Alq3 vapor deposition, which is a general organic EL film material, was performed. In the vapor deposition apparatus, a vapor deposition source 102 for evaporating a vapor deposition material is installed below a vapor deposition chamber 101 which is a vacuum chamber. A substrate W, which is a substrate to be deposited, is placed above the vapor discharge port 103 of the organic EL film material, and a deposition mask 104 is placed on the front surface of the substrate W, and held by a substrate holder (substrate holding means) 105 and a mask holder 106, respectively. Yes. The film thickness detection device 100 is installed adjacent to the substrate W toward the vapor deposition source 102.

  When the vapor deposition source 102 in the vapor deposition chamber was heated and stabilized at 300 ° C., the shutter (not shown) was opened and vapor deposition was started. The vapor deposition rate at this time is 10 Å / sec on the film thickness detection device 100, and the surface of the vibrator 5 in which the vapor flow of the vapor deposition material passes through the opening 3 of the shield 1 and is at the operating position A as shown in FIG. The deposition rate is detected from the deviation of the frequency due to the weight change. After 60 seconds, when the film thickness reached about 600 mm, the shutter was closed, the substrate W was replaced with a new one, and vapor deposition was started again. The temperature of the vapor deposition source 102 was controlled so that the vapor deposition rate was always maintained at 10 Å / sec.

  When this deposition process was repeated 30 times, the vibrator holder 4 was moved toward the shield 1 by the drive system 6 as shown in FIG. Next, the vibrator holder 4 was rotated 180 degrees by the drive system 6. Thereafter, the vibrator holder 4 was moved backward by the drive system 6 until it contacted the connection terminal 7 and the heater block 8. As a result, the vibrator 5 having the vapor deposition material attached to the surface is connected to the heater block 8 at the non-operation position B for regeneration, and the new vibrator 5 is connected to the connection terminal 7 at the operation position A for measurement. .

  Thereafter, vapor deposition was started again, and the vapor deposition rate was measured with the new vibrator 5. During the vapor deposition, the vibrator 5 at the inoperative position B is heated by heating the heater block 8 and holding at 350 ° C. for 10 minutes, and the vapor deposition material adhering to the vibrator 5 is gas. And was detached from the surface of the vibrator 5 and adhered to the wall surface of the cooled shield 1.

  After repeating the vapor deposition step 30 times, the vibrator holder 4 was driven again, the reproduced vibrator 5 and the vibrator 5 attached with the vapor deposition material were replaced, and the above steps were repeated under the same conditions.

  As described above, the deposition rate measurement step and the vibrator regeneration step were repeated 20 times, and then the deposition source 102 was cooled to complete the deposition. After the vapor deposition source 102 reached room temperature, the vapor deposition chamber 101 was opened to the atmosphere, and each vibrator 5 was observed. As a result, adhesion of Alq3 was not observed on the surface of the vibrator 5 after the regeneration process. When the film thicknesses of all the deposited substrates were measured, the film thickness at the center of the substrate was stable at 600 ± 40 mm.

1 is a schematic diagram illustrating a film thickness detection apparatus according to Example 1. FIG. It is a schematic diagram which shows a state when rotating a vibrator holder in the apparatus of FIG. It is a schematic diagram which shows a vapor deposition apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shield 2 Piping 3 Opening 4 Vibrator holder 5 Vibrator 7 Connection terminal 8 Heater block 100 Film thickness detection apparatus 101 Deposition chamber 102 Deposition source 103 Vapor discharge port 104 Mask 105 Substrate holder 106 Mask holder

Claims (5)

In the film thickness detection device that detects the film thickness of the thin film deposited on the deposition substrate in the deposition chamber by measuring the weight change of the vibrator,
A plurality of vibrators disposed in the vapor deposition chamber;
Each of the plurality of vibrators is moved between an operating position and a non-operating position in the deposition chamber;
Regenerating means for desorbing the vapor deposition material attached to each vibrator at the inoperative position;
And a driving means for detecting the film thickness of the thin film by vibrating each vibrator at the operating position.   The reproducing means has a heating means for desorbing the vapor deposition material attached to each vibrator by heating, and a shield held below the boiling point of the vapor deposition material, and the desorbed vapor deposition material is captured by the shield. The film thickness detection apparatus according to claim 1, wherein:   The moving means has a vibrator holder that is rotatable while holding the plurality of vibrators, and each vibrator is moved alternately to the operating position and the inoperative position by the rotation of the vibrator holder. The film thickness detection apparatus according to claim 1 or 2, characterized in that   A film thickness detecting device according to any one of claims 1 to 3, an evaporation source for evaporating an evaporation material and evaporating the evaporation material on an evaporation target substrate, and a substrate holding means for holding the evaporation target substrate. A vapor deposition apparatus characterized. In the vapor deposition method of evaporating the vapor deposition material in the vapor deposition chamber and depositing a thin film on the deposition target substrate,
A measurement step of detecting a film thickness of a thin film deposited on the deposition substrate by measuring a change in weight of a vibrator disposed in the deposition chamber;
A regeneration step of desorbing the deposition material attached to the vibrator by a regeneration means disposed in the deposition chamber;
The vapor deposition method characterized by alternately performing the measurement step and the regeneration step by the vibrator.

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