CN113471393B

CN113471393B - Film forming apparatus, film forming method, and method for manufacturing electronic device

Info

Publication number: CN113471393B
Application number: CN202110347231.XA
Authority: CN
Inventors: 岩崎达哉; 安川英宏; 锅岛健; 松本行生; 绪方俊宏; 渡部新; 菅原洋纪
Original assignee: Canon Tokki Corp
Current assignee: Canon Tokki Corp
Priority date: 2020-03-31
Filing date: 2021-03-31
Publication date: 2024-03-29
Anticipated expiration: 2041-03-31
Also published as: CN113471393A; KR102527120B1; KR102617764B1; KR20210122113A; KR20230059770A

Abstract

The invention provides a film forming apparatus, a film forming method, and a method for manufacturing an electronic device. A technique for realizing high-precision film thickness control and high productivity in a film forming apparatus having a structure in which a plurality of cluster units are connected. The film forming apparatus includes: a first unit having a cluster type first film forming chamber for forming a first layer on a substrate; a second unit having a cluster-type second film formation chamber in which a second layer is formed so as to overlap the first layer; a connection chamber which is arranged between the first unit and the second unit and connects adjacent cluster units; a film thickness measuring section provided at least partially in the passage chamber included in the connection chamber, for measuring a film thickness of a film formed on the substrate accommodated in the passage chamber; and a control unit for controlling at least one of the film formation conditions of the first film formation chamber and the second film formation chamber based on the film thickness measured by the film thickness measuring unit.

Description

Film forming apparatus, film forming method, and method for manufacturing electronic device

Technical Field

The present invention relates to a film forming apparatus, a film forming method, and a method for manufacturing an electronic device.

Background

In recent years, an organic EL display device (organic EL display) has been attracting attention as a flat panel display device. The organic EL display device is a self-luminous display, has characteristics such as a response speed, a viewing angle, and a thin thickness superior to those of a liquid crystal display, and has been widely used in place of an existing liquid crystal panel display in various portable terminals such as a monitor, a television, and a smart phone. Further, the application field thereof is also expanded to displays for automobiles and the like.

An organic EL element (organic light-emitting element, OLED: organic Light Emitting Diode) constituting an organic EL display device has a basic structure in which a functional layer having a light-emitting layer as an organic layer that generates light emission between two facing electrodes (cathode electrode, anode electrode) is formed. The functional layer and the electrode layer of the organic EL element can be produced by, for example, forming a film of a material constituting each layer on a substrate via a mask in a vacuum film forming apparatus.

The organic EL element is manufactured by sequentially transferring a substrate to each film forming chamber and sequentially forming electrodes and various functional layers on a surface to be processed of the substrate. Patent document 1 discloses a manufacturing apparatus having a structure in which a plurality of cluster units are connected, wherein a plurality of film forming chambers and inspection chambers are provided in each unit, and a substrate formed in a certain film forming chamber is transferred to the inspection chamber to measure the film thickness. Further, a structure is disclosed in which the light emission characteristics are simulated using the film thickness measurement result, and the chromaticity correction layer is formed in the same film forming chamber or another film forming chamber based on the simulation result.

[ Prior Art literature ]

[ patent literature ]

Japanese patent application laid-open No. 2005-322612 (patent document 1)

Disclosure of Invention

[ problem ] to be solved by the invention

In the structure of patent document 1, since the inspection chamber is provided in the cluster type unit, the substrate transfer robot disposed in the center of the unit has to be used to carry in and out the substrate to the inspection chamber. In this case, the substrate transfer robot is used only for inspection in the inspection chamber, and the operation rate of the substrate transfer robot increases as compared with the case where the inspection chamber is not provided in the cluster unit, which has a problem of increasing maintenance cost. Further, since one chamber usable for film formation is occupied in the inspection, the number of layers that can be formed by one unit (compared with the case where no inspection chamber is provided) is reduced. As a result, for example, the manufacturing can be performed by three units in the past, but there are disadvantages such as the need for four or more units. This disadvantage may lead to a decrease in productivity due to an increase in the number of steps required for transferring between cells, and may lead to an increase in the size of the entire manufacturing apparatus (an increase in the installation area).

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a technique for realizing high-precision film thickness control and high productivity in a film forming apparatus having a structure in which a plurality of cluster units are connected.

[ solution ] to solve the problem

The present disclosure includes a film forming apparatus characterized in that,

the film forming apparatus includes:

a first unit having a first transfer mechanism and a plurality of film forming chambers disposed around the first transfer mechanism and including a first film forming chamber for forming a first film on a substrate;

a cluster-type second unit having a second transfer mechanism and a plurality of film forming chambers disposed around the second transfer mechanism and including a second film forming chamber for forming a second film overlapping the first film on the substrate;

a connection chamber which is disposed on a transfer path of the substrate from the first unit to the second unit and connects the two cluster units; and

And a first measurement unit provided in the connection chamber at least partially for measuring a thickness of a film formed on the substrate.

[ Effect of the invention ]

According to the present invention, in a film forming apparatus having a structure in which a plurality of cluster units are connected, high-precision film thickness control and high productivity can be realized.

Drawings

Fig. 1 is a plan view schematically showing a structure of a part of an electronic device manufacturing apparatus.

Fig. 2 is a diagram schematically showing the structure of a vacuum deposition apparatus provided in a film formation chamber.

Fig. 3 is a cross-sectional view schematically showing the structure of the passage chamber.

Fig. 4 is a diagram showing an alignment mark and a patch for film thickness measurement on a substrate.

Fig. 5 is a block diagram schematically showing the structure of the film thickness measuring section.

Fig. 6 is a block diagram schematically showing the configuration of a film thickness control system.

Fig. 7 (a) is an overall view of the organic EL display device, fig. 7 (b) is a view showing a cross-sectional structure of one pixel, and fig. 7 (c) is an enlarged view of the red layer.

Fig. 8 is a diagram schematically showing a lamination process of the embodiment.

Fig. 9 is a time chart of a comparative example.

Fig. 10 is a timing chart of an embodiment.

Fig. 11 is a time chart of a comparative example.

Fig. 12 is a timing chart of an embodiment.

[ reference numerals description ]

CU1, CU2, CU3: cluster unit

EV11 to EV14, EV21 to EV24, EV31 to EV34: film forming chamber

RR1, RR2, RR3: transfer robot

CN1, CN2: connecting chamber

PS1, PS2: passageway chamber

S: substrate board

310: film thickness measuring unit

350: film thickness control unit

Detailed Description

Hereinafter, preferred embodiments and examples of the present invention will be described with reference to the accompanying drawings. However, the following embodiments and examples merely exemplify preferred configurations of the present invention, and the scope of the present invention is not limited to these configurations. The hardware configuration and software configuration, processing flow, manufacturing conditions, dimensions, materials, shapes, and the like of the apparatus in the following description are not intended to limit the scope of the present invention only to those described in detail unless otherwise specified.

The present invention can be applied to a device for sequentially transferring a substrate to a plurality of film forming chambers and depositing various materials on the surface of the substrate to form a film, and is preferably applied to a device for forming a thin film (material layer) having a desired pattern by vacuum vapor deposition. The substrate may be made of any material such as glass, a film of a polymer material, or a metal, or may be a substrate in which a film such as polyimide is laminated on a glass substrate. When a plurality of layers are formed on a substrate, the layer formed in the previous step is also referred to as a "substrate". As the vapor deposition material, any material such as an organic material or a metallic material (metal, metal oxide, or the like) may be selected. The present invention is applicable to a film forming apparatus including sputtering apparatuses and CVD (Chemical Vapor Deposition) apparatuses, in addition to the vacuum vapor deposition apparatus described in the following description. Specifically, the technique of the present invention can be applied to a manufacturing apparatus for an organic electronic device (for example, an organic EL element, a thin film solar cell, an organic photoelectric conversion element), an optical member, or the like. In particular, an apparatus for manufacturing an organic electronic device, in which an organic EL element or an organic photoelectric conversion element is formed by evaporating a deposition material and depositing the material onto a substrate through a mask having an opening pattern corresponding to a pixel or a sub-pixel, is one of preferred embodiments of the present invention. Among them, the apparatus for producing an organic EL element is one of particularly preferable application examples of the present invention.

< apparatus for manufacturing electronic device >

The electronic device manufacturing apparatus of fig. 1 is used for manufacturing a display panel of an organic EL display apparatus for a smart phone, for example. In the case of a display panel for a smart phone, for example, a 4 th and 5 th generation substrate (about 700 mm. Times.900 mm) or a 6 th generation full-size (about 1500 mm. Times.1850 mm) or half-cut-size (about 1500 mm. Times.925 mm) substrate is subjected to film formation for forming an organic EL element, and then the substrate is punched out to produce a plurality of small-size panels.

The electronic device manufacturing apparatus has a structure in which a plurality of cluster units (hereinafter also simply referred to as "units") CU1 to CU3 are connected via a connection chamber. The cluster unit is referred to as a film forming unit having a structure in which a plurality of film forming chambers are arranged around a substrate transfer robot serving as a substrate transfer mechanism. The number of units is not limited to three, and may be two or more. In the description of the unit common to all units and the description of the unit not specified, reference numerals denoted by "x" instead of numerals as in "CUx" may be used, and reference numerals denoted by numerals as in "CU1" are used in the description of the individual units (the same applies to reference numerals denoted by structures other than the units). Fig. 1 shows a part of a portion of a film forming apparatus in the whole electronic device manufacturing apparatus. For example, a substrate stocker, a heating device, a pretreatment device such as cleaning, and the like may be provided upstream of the film forming device, and for example, a sealing device, a processing device, a substrate stocker, and the like may be provided downstream of the film forming device, and the whole of them may be combined to form an electronic device manufacturing device.

The cluster unit CUx includes a central transfer chamber TRx, a plurality of film forming chambers EVx to EVx disposed around the transfer chamber TRx, and mask chambers MSx1 to MSx2. Two adjacent units CUx and CUx +1 are connected by a connecting chamber CNx. The chambers TRx, EVx1 to EVx4, MSx1 to MSx2, and the connecting chamber CNx in the cluster unit CUx are spatially connected, and the inside thereof is maintained in an inert gas atmosphere such as vacuum or nitrogen. In the present embodiment, each of the constituent unit CUx and the connecting chamber CNx is connected to a vacuum pump (vacuum evacuation mechanism), not shown, and can be evacuated independently. Each chamber is also referred to as a "vacuum chamber" or simply a "chamber". In the present specification, the term "vacuum" refers to a state filled with a gas having a pressure lower than the atmospheric pressure.

The transfer chamber TRx is provided with a transfer robot RRx as a transfer mechanism for transferring the substrate S and the mask M. The transfer robot RRx is, for example, an articulated robot having a structure in which a robot hand for holding the substrate S and the mask M is attached to an articulated arm. In the cluster unit CUx, the substrate S is transferred by a transfer mechanism such as a transfer robot RRx or a transfer robot RCx described later while maintaining a horizontal state in which a surface to be processed (a surface to be film-formed) of the substrate S is directed downward in the gravitational direction. The transfer robot RRx or the transfer robot RCx has a holding portion for holding the peripheral edge region of the surface to be processed of the substrate S. The transfer robot RRx transfers the substrate S between the upstream path chamber PSx-1, the film forming chambers EVx to EVx4, and the downstream buffer chamber BCx. The transfer robot RRx transfers the mask M between the mask chamber MSx1 and the film forming chambers EVx and EVx, and transfers the mask M between the mask chamber MSx2 and the film forming chambers EVx and EVx 4. The transfer robot RRx and the transfer robot RCx each perform a predetermined operation according to a predetermined program stored in the transfer control unit. When film formation is performed sequentially or simultaneously in parallel in a plurality of film forming chambers or units on a plurality of substrates, the operation of each robot is set so that the plurality of substrates are efficiently transferred. The position of the substrate on the transfer path may deviate from the ideal transfer position due to, for example, an error in the operation of the robot hand caused by a fluctuation in the arm flexibility or the like. In order to finely adjust the motion of the robot hand, a program for determining the motion of the robot hand is corrected as needed.

The mask chambers MSx1 to MSx2 are chambers provided with mask stockers for storing the masks M for film formation and the used masks M, respectively. The mask M used in the film forming chambers EVx1 and EVx is stored in the mask chamber MSx1, and the mask M used in the film forming chambers EVx2 and EVx4 is stored in the mask chamber MSx 2. As the mask M, a metal mask formed with a plurality of openings is preferably used.

The film forming chambers EVx to EVx are chambers for forming a film formation material layer on the surface of the substrate S. Here, the film forming chambers EVx and EVx3 have the same function (can perform the same film forming process), and similarly, the film forming chambers EVx and EVx4 have the same function. With this configuration, the film formation process of the first path such as the film formation chamber EVx to EVx2 and the film formation process of the second path such as the film formation chamber EVx3 to EVx4 can be performed in parallel.

The connection chamber CNx has a function of connecting the cell CUx to the cell CUx +1 and transferring the substrate S formed on the cell CUx to the cell CUx +1 at the rear stage. The connecting chamber CNx of the present embodiment is constituted by a buffer chamber BCx, a swirl chamber TCx, and a passage chamber PSx in this order from the upstream side. As described later, the structure of the connecting chamber CNx is preferable from the viewpoint of improving productivity of the film forming apparatus or usability. However, the structure of the connecting chamber CNx is not limited to this, and the connecting chamber CNx may be constituted by only the buffer chamber BCx or the passage chamber PSx.

The buffer chamber BCx is a chamber for transferring and receiving the substrate S between the transfer robot RRx in the cell CUx and the transfer robot RCx in the connection chamber CNx. The buffer chamber BCx has a function of adjusting the feed speed and feed timing of the substrates S by temporarily storing a plurality of substrates S when there is a difference in processing speed between the unit CUx and the subsequent unit CUx +1, or when the substrates S cannot be moved as usual due to the influence of a failure on the downstream side, or the like. By providing the buffer chamber BCx having such a function in the connecting chamber CNx, high productivity can be achieved, and high flexibility in film formation by lamination can be achieved in response to various layer structures. For example, the buffer chamber BCx is provided with: a substrate storage shelf (also referred to as a cassette) having a multistage structure capable of storing a plurality of substrates S in a horizontal state in which the surface to be processed of the substrates S is held downward in the gravity direction; and a lifting mechanism for lifting and lowering the substrate storage shelf so as to align the stage for feeding or discharging the substrate S to the transfer position.

The swirl chamber TCx is a chamber for rotating the orientation of the substrate S by 180 degrees. The transfer robot RCx for transferring the substrate S from the buffer chamber BCx to the passage chamber PSx is provided in the spin chamber TCx. When the upstream end of the substrate S is referred to as the "rear end" and the downstream end is referred to as the "front end", the transfer robot RCx rotates 180 degrees while supporting the substrate S received in the buffer chamber BCx and delivers the substrate S to the passage chamber PSx, whereby the front end and the rear end of the substrate S are replaced in the buffer chamber BCx and the passage chamber PSx. In this way, the upstream side unit CUx and the downstream side unit CUx +1 are oriented the same when the substrate S is fed into the film forming chamber, and therefore the scanning direction for film formation of the substrate S and the orientation of the mask M can be made uniform in each unit CUx. With such a configuration, the orientation of the mask M provided to the mask chambers MSx1 to MSx2 can be made uniform in each unit CUx, and the management of the mask M can be simplified and the usability can be improved.

The passage chamber PSx is a chamber for transferring the substrate S between the transfer robot RCx in the connection chamber CNx and the transfer robot rrx+1 in the downstream unit CUx +1. In the present embodiment, alignment of the substrate S and measurement of the film thickness of the film formed on the substrate S are performed in the passage chamber PSx. In this way, by disposing the alignment mechanism and the film thickness measuring section in the same chamber and measuring the film thickness after alignment is performed, the positional accuracy of the film thickness measuring section in the substrate can be improved. Thus, the film thickness measurement portion in the substrate can be kept constant in each substrate, and the film thickness can be evaluated with high accuracy.

A gate (for example, a gate valve or a gate valve) that can be opened and closed may be provided between the film forming chambers EVx to EVx, the mask chambers MSx1 to MSx2, the transfer chamber TRx, the buffer chamber BCx, the spin chamber TCx, and the passage chamber PSx, or may be an always open structure.

< vacuum deposition apparatus >

Fig. 2 schematically shows the structure of the vacuum vapor deposition apparatus 200 provided in the film formation chambers EVx to EVx 4.

The vacuum vapor deposition apparatus 200 includes a mask holder 201 that holds a mask M, a substrate holder 202 that holds a substrate S, an evaporation source unit 203, a moving mechanism 204, a film formation rate monitor 205, and a film formation control unit 206. The mask holder 201, the substrate holder 202, the evaporation source unit 203, the moving mechanism 204, and the film formation rate monitor 205 are provided in the vacuum chamber 207. The vacuum vapor deposition apparatus 200 further includes a position adjustment mechanism (alignment mechanism) not shown, which moves at least one of the mask holder 201 and the substrate holder 202 to perform alignment (alignment) between the mask M held by the mask holder 201 and the substrate S held by the substrate holder 202.

The substrate S is placed on the upper surface of the mask M held in a horizontal state with the surface to be processed facing down. An evaporation source unit 203 is provided below the mask M. The evaporation source unit 203 generally includes a container (crucible) for containing a film forming material, a heater for heating the film forming material in the container, and the like. Further, reflectors, heat transfer members, baffles, and the like for improving the heating efficiency may be provided in the evaporation source unit 203 as needed. The moving mechanism 204 is a mechanism for moving (scanning) the evaporation source unit 203 in parallel with the surface to be processed of the substrate S. In the present embodiment, the single-axis movement mechanism 204 is used, but a movement mechanism having two or more axes may be used. In the present embodiment, the substrate S is placed on the upper surface of the mask M, but the substrate S may not be placed on the upper surface of the mask M as long as the substrate S is sufficiently adhered to the mask M. In the present embodiment, a magnet, not shown, is brought close to the surface of the substrate S opposite to the surface to be processed, and the mask foil of the mask M is magnetically attracted, thereby improving adhesion of the mask M to the substrate S. In fig. 2, the evaporation source unit 203 is shown as one unit, but a plurality of evaporation source units or containers may be arranged in parallel and integrally moved. According to such a configuration, different materials can be stored in each evaporation source unit or container and evaporated, and a mixed film or a laminated film can be formed.

The film formation rate monitor 205 is a sensor for monitoring the film formation rate of a thin film formed on the substrate S. The film formation rate monitor 205 is a crystal oscillation type film formation rate monitor, and has a crystal oscillator that moves together with the evaporation source unit 203, and estimates each unit based on the amount of change in resonance frequency (natural frequency) caused by deposition of a film formation material on the surface (mass) of the crystal oscillatorDeposition rate (deposition rate) which is the deposition amount of the deposition material at the time. The film formation rate monitor 205 may be disposed in the vicinity of the surface to be processed of the substrate S.

The film formation control unit 206 controls the film formation rate based on the film formation rate obtained by the film formation rate monitor 205The film forming time s is adjusted by a film thickness value evaluated by a first film thickness measuring unit to be described later]Thereby controlling the thickness of the thin film formed on the substrate S to a target value. The film formation time is adjusted by changing the scanning speed of the evaporation source unit 203 by the moving mechanism 204. In the present embodiment, the film thickness is controlled by adjusting the film formation time (adjusting the scanning speed), but the evaporation amount (ejection amount) of the material may be controlled by adjusting the heater temperature of the evaporation source unit 203, the shutter opening of the evaporation source unit 203, or the like, as is generally performed in the conventional vacuum vapor deposition apparatus. The film formation control unit 206 may also perform a combination of adjustment of the film formation time and adjustment of the evaporation amount. That is, the film formation control unit 206 may control at least one of the scanning speed, the heater temperature, and the shutter opening of the evaporation source unit 203. The configuration of measuring (acquiring) the film thickness of the film formed on the substrate in the film forming chamber using the film forming rate monitor 205 corresponds to the second film thickness measuring section of the present invention.

< alignment mechanism of passage Chamber >

Fig. 3 is a cross-sectional view schematically showing the structure of the passage chamber PSx. Fig. 3 corresponds to section A-A of fig. 1.

An alignment mechanism for aligning the substrate S is provided in the passage chamber PSx. The substrate S transferred through the transfer chamber TRx and the spin chamber TCx has a positional variation due to positional accuracy of the robot used for transfer. In the present embodiment, the misalignment can be suppressed by the alignment mechanism provided in the passage chamber PSx. The alignment mechanism generally has: a substrate tray 301 disposed inside the vacuum chamber 300; an xyθ driving device 302 for driving the substrate tray 301 in the X-axis direction, the Y-axis direction, and the θ direction; a camera 305 for photographing (the alignment mark 304 of) the substrate S through a window 303 provided on the bottom surface of the vacuum chamber 300; and an alignment control section 306. The camera 305 and the alignment control unit 306 correspond to a position acquisition mechanism that acquires position information of the substrate S disposed inside the vacuum chamber 300 with respect to the vacuum chamber 300. Based on the acquired positional information, the xyθ driving device 302 as a moving mechanism relatively moves the substrate S with respect to the vacuum chamber 300. In the present embodiment, the passage chamber PSx is configured to be capable of accommodating only one substrate, but may be configured to be capable of accommodating a plurality of substrates.

When the substrate S is placed on the substrate tray 301 by the transfer robot RCx in the whirl chamber TCx, the alignment mark 304 of the substrate S is photographed by the camera 305. The alignment control unit 306 detects the position and the inclination of the alignment mark 304 from the image captured by the camera 305, and thereby calculates the positional deviation amount (Δx, Δy) and the rotational deviation amount (Δθ) of the substrate S from the reference position. Then, the alignment control unit 306 controls the xyθ driving device 302 to correct the positional deviation and the rotational deviation of the substrate S, thereby aligning the substrate S. A reference mark indicating a reference position may be provided in the passage chamber PSx. Further, the reference mark may be captured when the alignment mark 304 of the substrate S is captured by the camera 305, and the positional deviation amount and the rotational deviation amount of the substrate S with respect to the reference position may be obtained.

When the substrate S is formed in the film forming chambers EVx to EVx, the substrate S and the mask M need to be aligned with high accuracy. Therefore, in the film forming chambers EVx to EVx, the substrate S needs to be positioned with ultra-high precision, which is called precise alignment. As in the present embodiment, by performing the rough alignment of the substrate S in the passage chamber PSx in advance, the initial deviation amount when the substrate S is fed into the film forming chamber of the rear stage unit CUx +1 is suppressed to be small, and therefore, the time required for performing the precise alignment in the film forming chamber can be shortened. Further, by performing (rough) alignment in advance before film thickness measurement, the positional accuracy of the film thickness measurement portion in the substrate can be improved. Thus, the film thickness measurement portion in the substrate can be kept constant in each substrate, and the film thickness can be evaluated with high accuracy.

Fig. 4 shows an example of the alignment mark 304 on the substrate S. In this example, alignment marks 304 are attached to both corners of the rear end side of the substrate S, respectively. However, the arrangement of the alignment mark 304 is not limited to this, and may be arranged at the corner of the tip side, at two corners or all four corners of the diagonal, or at a position along the edge instead of the corner. The number of alignment marks 304 is also arbitrary. Alternatively, instead of the alignment mark 304 on the substrate S, the edge or corner of the substrate S may be detected.

< film thickness measuring section >

As shown in fig. 3, a film thickness measuring section 310, which is a first film thickness measuring section for measuring the film thickness of the film formed on the substrate S, is provided in the passage chamber PSx. In fig. 3, only one film thickness measuring unit 310 is shown, but a plurality of film thickness measuring units may be provided. By evaluating a plurality of portions at a time, information on the fluctuation of film thickness in the substrate surface or a plurality of kinds of films formed in a plurality of film forming chambers can be obtained and evaluated at once.

The film thickness measuring unit 310 is a sensor (optical sensor) that optically measures the film thickness, and in the present embodiment, a reflection spectroscopic film thickness meter is used. The film thickness measuring section 310 is generally composed of a film thickness evaluating unit 311, a sensor head 312, and an optical fiber 313 connecting the sensor head 312 and the film thickness evaluating unit 311. The sensor head 312 is disposed below the substrate tray 301 in the vacuum chamber 300, and is connected to the optical fiber 313 via a vacuum flange 314 attached to the bottom surface of the vacuum chamber 300. The sensor head 312 has a function of setting the irradiation area of the light guided through the optical fiber 313 to a predetermined area, and optical members such as an optical fiber, a pinhole, and a lens can be used.

Fig. 5 is a block diagram of the film thickness measuring unit 310. The film thickness evaluation unit 311 includes a light source 320, a beam splitter 321, and a measurement control unit 322. The light source 320 is a device for measuring light output, and for example, a heavy hydrogen lamp, a xenon lamp, a halogen lamp, or the like can be used. As the wavelength of light, a range of 200nm to 1 μm can be used. The spectroscope 321 is a device that splits the reflected light input from the sensor head 312 and measures the spectrum (intensity of each wavelength), and is constituted by, for example, a detector that performs photoelectric conversion with a spectroscopic element (grating, prism, or the like). The measurement control unit 322 is a device that performs control of the light source 320, calculation of film thickness based on reflection spectrum, and the like.

The measurement light output from the light source 320 is guided to the sensor head 312 via the optical fiber 313, and is projected from the sensor head 312 toward the substrate S. Light reflected by the substrate S is input from the sensor head 312 to the beam splitter 321 via the optical fiber 313. At this time, light reflected at the surface of the thin film on the substrate S and light reflected at the interface between the thin film and the underlying layer thereof interfere with each other. This is affected by interference or absorption by the thin film, and thus the reflection spectrum is affected by the optical path length difference, i.e., the film thickness. The thickness of the thin film can be measured by analyzing the reflection spectrum by the measurement control unit 322. The above-described reflection spectroscopic film thickness evaluation is a preferable method for evaluating an organic layer of an organic EL element because it can perform highly accurate evaluation in a short time even for an organic film having a thickness of several nm to several hundred nm. Here, as a material of the organic layer, αnpd: hole transport materials such as α -naphthylphenylbiphenyldiamine (α -naphthylphenylbiphenyl diamine), ir (ppy) 3: luminescent materials such as tris (2-phenylpyridine) Iridium (Iridium-phenylpivoted) complex, alq3: tris (8-hydroxyquinoline) aluminum (Tris (8-quinolato) aluminum) or Liq: and electron transport materials such as 8-hydroxyquinoline-lithium (8-hydroxyquinoline-lithium). In addition, the present invention can be applied to a mixed film of the above-described organic materials.

Fig. 4 shows an example of a thin film for measuring the film thickness formed on the substrate S. The substrate S is provided with a film thickness measuring region 330 at a position (in the illustrated example, a front end portion of the substrate S) not overlapping with a region where the display panel 340 is formed. At the time of film formation processing in each film formation chamber, film formation to a predetermined position in the film thickness measurement region 330 is also performed in parallel with film formation to a portion of the display panel 340, whereby a thin film for film thickness measurement (hereinafter referred to as a measurement patch 331; also referred to as a measurement sheet or an organic film for evaluation) is formed in the film thickness measurement region 330. This can be easily achieved by forming the openings for the measurement patches 331 in advance in the mask M used in each film forming chamber.

The film thickness measurement region 330 is set to an area where a plurality of measurement patches 331 can be formed, and it is preferable to change the formation position of the measurement patch 331 in layer units to be the measurement target of the film thickness. That is, when it is desired to measure the film thickness of a film formed in one film forming chamber (single film or laminated film in which a plurality of films are laminated), it is preferable that only a film formed in one film forming chamber (single film or laminated film) is formed in the portion of the measurement patch 331, and when it is desired to measure the film thickness of a laminated film formed through a plurality of film forming chambers, it is preferable that the same laminated film as the laminated film to be measured is formed in the portion of the measurement patch 331. By thus making the measurement patch 331 different for each layer to be measured, accurate measurement of the film thickness can be achieved. As described above, in the configuration in which the film thickness measurement is performed after alignment, since the accuracy of the film thickness measurement position is high, the number of the measurement patches 331 can be reduced, and the measurement patches can be arranged at a high density. This can reduce the area of the film thickness measuring region 330 in the substrate, and can further increase the display panel 340 formed on the substrate.

< control of film thickness with high precision >

The vacuum vapor deposition apparatus 200 of each film formation chamber is controlled as described above so that the film formation rate of the film formed by using the film formation rate monitor 205 becomes the target film formation rate. However, the film formation rate monitor 205 does not directly measure the thickness of the film formed on the substrate S, but only indirectly measures the film formation rate by a crystal oscillator disposed at a position different from the substrate S. Therefore, there are cases where the film thickness of the crystal oscillator film deposited on the film formation monitor 205 is different from the film thickness of the film deposited on the substrate S or the measured value itself of the film formation monitor 205 is subject to errors due to various errors such as the amount of material deposited on the crystal oscillator or the temperature of the crystal oscillator. Since a measurement error of the film thickness of the film formed on the substrate S by the film formation rate monitor 205 causes a fluctuation in the film thickness, a decrease in the panel quality and a decrease in the yield, countermeasures are required.

Therefore, in the present embodiment, the thickness of the thin film formed on the substrate S is directly measured by the film thickness measuring unit 310, and the film forming conditions of each film forming chamber are controlled based on the measurement result, thereby realizing high-precision film thickness control. In the control of the film formation conditions, both the value of the film formation rate monitor 205 and the measurement result of the film thickness measurement unit 310 may be used. The film formation rate monitor 205 for evaluating the amount of deposition on the crystal oscillator is different from the film thickness measuring unit 310 for optically evaluating the film thickness on the substrate S in terms of measurement principle, and thus operates differently with respect to disturbance, fluctuation in the environment or the film formation state, and the like. Therefore, by using a plurality of evaluation means having different measurement principles, it is possible to control the film thickness with higher reliability.

Fig. 6 is a block diagram schematically showing the configuration of a film thickness control system. The film thickness control unit 350 transmits a control command to the film formation control unit 206 of each film formation chamber based on the measurement result of the film thickness measurement unit 310. Methods for controlling the film formation conditions are largely classified into feedback control and feedforward control. The feedback control is a control for adjusting the film thickness of the subsequent substrate Ss by controlling the film forming conditions of the film forming chamber on the upstream side of the film thickness measuring section 310 by the film thickness control section 350. The feed-forward control is a control for adjusting the film thickness of the substrate S measured by the film thickness measuring unit 310 by controlling the film forming conditions of the film forming chamber downstream of the film thickness measuring unit 310 by the film thickness control unit 350. The film thickness control unit 350 may perform only one of feedback control and feedforward control, or may perform both of them. The control method may be different for each film forming chamber or each unit. The film forming conditions to be controlled are, for example, film forming time, scanning speed of the evaporation source unit 203, heater temperature of the evaporation source unit 203, shutter opening of the evaporation source unit 203, and the like. The film thickness control unit 350 may control any one of the film formation conditions, or may control a plurality of film formation conditions. In the present embodiment, the scanning speed is controlled.

According to the film forming apparatus (electronic device manufacturing apparatus) of the present embodiment, since the mechanism for adjusting the film forming conditions based on the measurement result of the film thickness measuring unit 310 is provided, it is possible to correct the error of the film forming rate monitor 205 caused by the crystal oscillator and realize high-precision film thickness control. Further, by disposing the film thickness measuring unit 310 in the connecting chamber instead of the cluster unit, the increase in size (increase in installation area) of the apparatus can be suppressed. Further, since the film thickness measurement can be performed by using the time for which the substrate is temporarily left in the connection chamber for the transfer of the substrate between the units, the influence of the film thickness measurement on the productivity (throughput) of the entire apparatus can be reduced as much as possible. In particular, in a film forming apparatus in which a plurality of film forming chambers are connected to a cluster unit, high productivity can be maintained.

< method for manufacturing electronic device >

Next, an example of a method for manufacturing an electronic device will be described. Hereinafter, a structure and a manufacturing method of the organic EL display device are exemplified as examples of the electronic device.

First, the organic EL display device manufactured will be described. Fig. 7 (a) is an overall view of the organic EL display device 50, fig. 7 (b) is a view showing a cross-sectional structure of one pixel, and fig. 7 (c) is an enlarged view of the red layer.

As shown in fig. 7 (a), a plurality of pixels 52 each including a plurality of light emitting elements are arranged in a matrix in a display region 51 of the organic EL display device 50. The light emitting elements each have a structure including an organic layer sandwiched between a pair of electrodes, and details thereof will be described later. Here, the pixel means the minimum unit that can display a desired color in the display area 51. In the case of a color organic EL display device, the pixel 52 is constituted by a combination of a plurality of sub-pixels of the first light emitting element 52R, the second light emitting element 52G, and the third light emitting element 52B which exhibit mutually different light emission. The pixel 52 is often composed of a combination of three types of sub-pixels, that is, a red (R) light-emitting element, a green (G) light-emitting element, and a blue (B) light-emitting element, but is not limited thereto. The pixel 52 may include at least one type of sub-pixel, preferably two or more types of sub-pixels, and more preferably three or more types of sub-pixels. The sub-pixels constituting the pixel 52 may be, for example, a combination of four types of sub-pixels, that is, a red (R) light-emitting element, a green (G) light-emitting element, a blue (B) light-emitting element, and a yellow (Y) light-emitting element, or may be a combination of a yellow (Y) light-emitting element, a cyan (C) light-emitting element, and a magenta (M) light-emitting element.

Fig. 7 (B) is a schematic partial cross-sectional view at line a-B of fig. 7 (a). The pixel 52 includes a plurality of sub-pixels each including an organic EL element including a first electrode (anode) 54, a hole transport layer 55, any of a red layer 56R/a green layer 56G/a blue layer 56B, an electron transport layer 57, and a second electrode (cathode) 58 on a substrate 53. Among them, the hole transport layer 55, the red layer 56R, the green layer 56G, the blue layer 56B, and the electron transport layer 57 correspond to organic layers. The red layer 56R, the green layer 56G, and the blue layer 56B are formed in patterns corresponding to light emitting elements (sometimes also referred to as organic EL elements) that emit red, green, and blue, respectively. The first electrode 54 is formed separately for each light emitting element. The hole transport layer 55, the electron transport layer 57, and the second electrode 58 may be formed in common across the plurality of light emitting elements 52R, 52G, and 52B, or may be formed for each light emitting element. That is, as shown in fig. 7 (B), the hole transport layer 55 may be formed as a layer common to a plurality of sub-pixel regions, the red layer 56R, the green layer 56G, and the blue layer 56B may be formed separately for each sub-pixel region, and the electron transport layer 57 and the second electrode 58 may be formed as a layer common to a plurality of sub-pixel regions thereon. An insulating layer 59 is provided between the first electrodes 54 in order to prevent short-circuiting between the adjacent first electrodes 54. Further, the organic EL layer is degraded by moisture or oxygen, and thus a protective layer 60 for protecting the organic EL element from moisture or oxygen is provided.

In fig. 7 (b), the hole transporting layer 55 or the electron transporting layer 57 is represented by one layer, but may be formed by a plurality of layers having a hole blocking layer or an electron blocking layer according to the structure of the organic EL display element. A hole injection layer having a band structure that allows smooth injection of holes from the first electrode 54 to the hole transport layer 5 may be formed between the first electrode 54 and the hole transport layer 55. Also, an electron injection layer may be formed between the second electrode 58 and the electron transport layer 57.

The red layer 56R, the green layer 56G, and the blue layer 56B may be each formed of a single light-emitting layer, or may be formed by stacking a plurality of layers. Fig. 7 (c) shows an example in which the red layer 56R is formed by two layers. For example, a red light-emitting layer may be used as the upper layer 56R2, and a hole-transporting layer or an electron blocking layer may be used as the lower layer 56R1. Alternatively, the red light-emitting layer may be the lower layer 56R1, and the electron transport layer or the hole blocking layer may be the upper layer 56R2. By providing a layer below or above the light-emitting layer in this manner, the light-emitting position in the light-emitting layer is adjusted, and the light path length is adjusted, thereby improving the color purity of the light-emitting element. Although fig. 7 (c) shows an example of the red layer 56R, the same configuration may be adopted for the green layer 56G or the blue layer 56B. The number of layers may be two or more. In addition, layers of different materials may be stacked such as a light-emitting layer and an electron blocking layer, or for example, two or more layers of the same material may be stacked as the light-emitting layer.

Next, an example of a method for manufacturing the organic EL display device will be specifically described. Here, it is assumed that the red layer 56R is composed of two layers, i.e., the lower layer 56R1 and the upper layer 56R2, and the green layer 56G and the blue layer 56B are composed of a single light-emitting layer.

First, a substrate 53 on which a circuit (not shown) for driving the organic EL display device and a first electrode 54 are formed is prepared. The material of the substrate 53 is not particularly limited, and may be made of glass, plastic, metal, or the like. In the present embodiment, as the substrate 53, a substrate in which a film of polyimide is laminated on a glass substrate is used.

A resin layer of acrylic, polyimide, or the like is applied by bar coating or spin coating on the substrate 53 on which the first electrode 54 is formed, and the insulating layer 59 is formed by patterning the resin layer by photolithography so that an opening is formed at a portion where the first electrode 54 is formed. The opening corresponds to a light emitting region where the light emitting element actually emits light.

The substrate 53 patterned with the insulating layer 59 is fed into the first film formation chamber, and the hole transport layer 55 is formed as a common layer on the first electrode 54 in the display region. The hole transport layer 55 is formed using a mask having openings formed in the display region 51, and the display region 51 is finally a panel portion of each organic EL display device. The mask used in the first film formation chamber is also provided with an opening in a portion of the substrate 53 corresponding to the film thickness measurement region 330, which is different from a portion corresponding to the region where the display panel 340 is formed. The opening is formed at a position different from a mask used in the other film forming chamber in a portion corresponding to the film thickness measuring region 330. Thus, the measurement patch 331 having only the hole transport layer 55 formed thereon can be formed in the film thickness measurement region 330.

Next, the substrate 53 formed with the hole transport layer 55 is fed into the second film formation chamber. The alignment of the substrate 53 and the mask is performed, the substrate is placed on the mask, and the lower layer 56R1 (for example, a hole transport layer or an electron blocking layer) is formed on the hole transport layer 55 at a portion where the red element of the substrate 53 is arranged (a region where a red sub-pixel is formed). Then, the substrate 53 is fed into the third film formation chamber, and the upper layer 56R2 (for example, a red light-emitting layer) is formed on the lower layer 56R1 in a superimposed manner. Here, the masks used in the second film formation chamber and the third film formation chamber are high-definition masks in which openings are formed in a plurality of regions of only red sub-pixels among a plurality of regions on the substrate 53 serving as sub-pixels of the organic EL display device. Thus, the lower layer 56R1 and the upper layer 56R2 are formed only in the red subpixel region among the plurality of subpixel regions on the substrate 53. In other words, the lower layer 56R1 and the upper layer 56R2 are not formed in the region of the blue sub-pixel and the region of the green sub-pixel, and are formed in the region of the red sub-pixel, out of the regions of the plurality of sub-pixels on the substrate 53. In the mask used in the second film formation chamber and the mask used in the third film formation chamber, a common opening pattern is formed in a portion of the substrate 53 corresponding to the land where the display panel 340 is formed, but the opening pattern is different in a portion corresponding to the film thickness measurement region 330. That is, by forming openings at different positions in the respective masks in the portions corresponding to the film thickness measurement regions 330, the measurement patch 331 in which only the lower layer 56R1 is formed and the measurement patch 331 in which only the upper layer 56R2 is formed can be formed.

In the same manner as the formation of the red layer 56R, a green layer 56G is formed in the fourth film formation chamber, and a blue layer 56B is formed in the fifth film formation chamber. After the formation of the red layer 56R, the green layer 56G, and the blue layer 56B is completed, the electron transport layer 57 is formed on the entire display region 51 in the sixth film formation chamber. The electron transport layer 57 is formed as a common layer on the three-color layers 56R, 56G, 56B.

The substrate formed with the electron transport layer 57 is moved to the seventh film formation chamber, and the second electrode 58 is formed. In the present embodiment, the layers are formed by vacuum deposition in the first to seventh film forming chambers. However, the present invention is not limited thereto, and for example, the film formation of the second electrode 58 in the seventh film formation chamber may be performed by sputtering. Then, the substrate formed with the second electrode 68 is moved to a sealing device, and the protective layer 60 is formed by plasma CVD (sealing step), thereby completing the organic EL display device 50. The protective layer 60 is formed by CVD, but is not limited thereto, and may be formed by ALD or inkjet.

When the substrate 53 on which the insulating layer 59 is patterned is fed to the film forming apparatus until the formation of the protective layer 60 is completed, if the substrate is exposed to an atmosphere containing moisture or oxygen, there is a possibility that the light-emitting layer made of the organic EL material may be degraded by the moisture or oxygen. Therefore, the transfer of the substrate between the film forming chambers is performed in a vacuum atmosphere or an inert gas atmosphere.

When the red layer 56R, the green layer 56G, and the blue layer 56B are each composed of a single light-emitting layer, a red light-emitting layer is formed in the second film formation chamber or the third film formation chamber, and then the substrate is transferred to the fourth transfer chamber. In this case, either the second film formation chamber or the third film formation chamber may be omitted.

< example of film thickness control >

Specific examples of film thickness control by the film thickness control system will be described. In example 1, after the first layer was formed in the first film forming chamber, film thickness control was performed in which film thickness information of the first layer measured by the first film thickness measuring section in the passage chamber was fed back to the film forming condition of the first film forming chamber. In example 2, in a lamination process in which a first layer is formed and then a second layer is formed on the first layer in a superimposed manner, film thickness control is performed in which film thickness information of the first layer measured by the first film thickness measuring section in the passage chamber is fed forward to film forming conditions in the second film forming chamber. That is, the specific configuration example of the present embodiment controls at least one of the film formation conditions of the first film formation chamber (first film formation conditions) and the second film formation chamber (second film formation conditions) as the control step based on the film thickness measured in the film thickness measurement step.

Example 1

The description will be made with reference to fig. 1. For example, after a first layer is formed on the substrate S in the film forming chamber EV12, the substrate S is transferred from the film forming chamber EV12 to the buffer chamber BC1 by the transfer robot RR 1. Next, the transfer robot RC1 in the connection chamber CN1 transfers the substrate S1 from the buffer chamber BC1 to the passage chamber PS1, and the alignment of the substrate S1 is performed in the passage chamber PS 1. Then, the film thickness of the first layer is measured in the passage chamber PS1 by the film thickness measuring unit 310. The film thickness control unit 350 performs feedback control to the film forming chamber EV12 in the unit CU1 based on the film thickness information of the first layer acquired in the passage chamber PS1, and adjusts the film forming conditions at the time of forming the subsequent substrate in the film forming chamber EV 12. For example, the scanning speed (transport speed) of the evaporation source in the film formation chamber EV12 is adjusted. In this case, when the measured value of the film thickness is smaller than the target film thickness, the scanning speed of the evaporation source in the film formation chamber EV12 is adjusted so as to be slower, and when the measured value of the film thickness is thicker than the target film thickness, the scanning speed of the evaporation source in the film formation chamber EV12 is adjusted so as to be faster. By performing such feedback control, a good film thickness can be obtained for a subsequent substrate that is subjected to a film formation process after the substrate S.

In this embodiment, film formation is performed while sequentially transferring a plurality of substrates in a plurality of cluster units included in a film forming apparatus (electronic device manufacturing apparatus). For example, focusing on the order of the nth substrate (in other words, the nth passing substrate in the passage chamber PS 1) flowing in the transfer path in the film forming apparatus, the film thickness information of the first layer formed on the nth substrate in the film forming chamber EV12 acquired through the passage chamber PS1 is fed back to the film forming conditions at the time of forming the (n+1) th and subsequent substrates in the film forming chamber EV 12.

From the standpoint of rapidly performing feedback control to increase the number of good film thickness substrates (reduce the number of substrates that may become defective), it is preferable to feed back the film thickness information of the first layer formed on the nth substrate to the film forming conditions at the time of forming the (n+1) th substrate, which is the immediately subsequent substrate after film formation in the film forming chamber EV 12. Thus, for example, when the film thickness of the first layer of the nth substrate deviates from the target value, the occurrence of the substrate having the film thickness of the first layer deviating from the target value as much as possible can be suppressed. This can be easily achieved if film formation on the (n+1) -th substrate in the film formation chamber EV12 is started after waiting for completion of acquisition of film thickness information of the first layer of the n-th substrate in the passage chamber PS 1. However, the film formation on the (n+1) -th substrate in the film formation chamber EV12 may be started without waiting for the acquisition of the film thickness information of the first layer of the n-th substrate in the passage chamber PS1 to be completed. In this case, the film thickness information of the first layer of the n-th substrate in the passage chamber PS1 may be acquired before the film formation of the (n+1) -th substrate in the film formation chamber EV12 is completed, and the feedback control may be performed in the middle of the film formation of the (n+1) -th substrate in the film formation chamber EV 12. At this time, the film thickness of the film formed at a certain point in the film formation of the (n+1) th substrate in the film formation chamber EV12 is estimated based on the film thickness information of the first layer of the nth substrate, and the difference to the target film thickness is calculated, so that the remaining film formation in the film formation chamber EV12 can be controlled so that the film of the difference film thickness can be formed. Thus, film formation on the (n+1) -th substrate is started without waiting for completion of acquisition of film thickness information on the (n+1) -th substrate, and feedback control is performed in the middle of film formation on the (n+1) -th substrate, whereby high productivity and high-precision film thickness control can be realized.

In the structure of this embodiment, the film forming chambers EV12 and EV14 form layers of the same material for the substrates fed in. The film forming chambers EV12 and EV14 are configured such that two stages (substrate holders) are disposed in the respective film forming chambers, and a mask and a substrate are placed on one stage while film forming processing is performed on the other stage. One evaporation source unit (film forming source) for discharging a material to a substrate held on a stage is provided in each film forming chamber, and when film forming in one stage is completed, the evaporation source unit moves to a position below the other stage, and film forming on the substrate mounted on the other stage having completed is started. By adopting such a structure, improvement in productivity can be achieved. At this time, if two stations of the film forming chamber EV12 are the stations ST12A and ST12B and two stations of the film forming chamber EV14 are the stations ST14A and ST14B, the film thickness information of the substrate formed by the station ST12A is preferably fed back to the film forming in the stations ST12A and ST12B, and more preferably fed back only to the film forming in the station ST 12A. Since the tables ST12A and ST12B are formed by the same evaporation source unit, the film thickness of the formed film is easily the same, and thus by performing feedback control commonly to the two tables, high-precision film thickness control can be effectively performed. Even when the same evaporation source unit is used, the film thickness of the film to be formed may be slightly different depending on the position of the evaporation source unit. Therefore, by feeding back the film thickness information of the film formed on a specific stage only to the film formed on the specific stage, it is possible to realize more accurate film thickness control. In the case of performing the feedback control more promptly, the film thickness information of the film formed by the film forming chamber EV12 may be feedback-controlled to the film formed in the film forming chamber EV 14. The application destination of such feedback control can also be switched by the user's operation.

As described above, in the present embodiment, a plurality of stages are provided in one film forming chamber, and the application destination of feedback can be determined for each film forming chamber or each stage. Accordingly, the film thickness control unit 350 may further include a storage unit (not shown) for storing the film thickness information acquired by the film thickness measuring unit 310 in association with the information of the film forming chamber in which the film is formed and the information of the stage in the film forming chamber.

Comparative example

As a comparative example, a configuration is shown in which the film thickness measuring unit 310 is provided in the film forming chamber EV12, but is not provided in the passage chamber PS 1. In the comparative example, after the first layer was formed on the substrate S in the film forming chamber EV12, the film thickness of the first layer formed on the substrate S was measured by the film thickness measuring unit 310 in the film forming chamber EV 12. The film thickness control unit 350 performs feedback control with respect to the film formation chamber EV12 based on the film thickness information of the first layer acquired in the film formation chamber EV12, and adjusts the film formation conditions at the time of film formation of the subsequent substrate through the film formation chamber EV 12.

In the comparative example, since the film thickness measurement is performed in the film forming chamber EV12 after the film forming process is completed, the flow of the substrate S in the first unit CU1 is temporarily stopped in the film forming chamber EV 12. Therefore, the time required for film thickness measurement slows down the substrate transfer to the next unit, which becomes a rate limit and deteriorates the throughput of the entire apparatus. In contrast, in example 1, since the film thickness is measured in the passage chamber PS1, the influence on the manufacturing tact or the feedback of the film formation conditions can be reduced without affecting the influence. In the transfer path of the substrate S, the connection chamber CN1 including the passage chamber PS1 is a zone for adjusting the timing of sending the substrate S to the second unit CU2 according to the progress of the film formation process of the preceding substrate in the downstream second unit CU 2. That is, the film thickness can be measured by using the time (period) for adjusting the timing. Therefore, feedback of the film formation conditions can be performed without affecting the manufacturing tact.

A specific example of a method for manufacturing an electronic device to which the present embodiment is applied will be described. Here, a lamination process in which a first layer is formed as a common layer and then a second layer and a third layer are formed in parallel thereon is exemplified as shown in fig. 8. For example, in the case of the organic EL display device shown in fig. 7 (b), the hole transport layer 55 corresponds to the first layer, the red layer 56R corresponds to the second layer, and the green layer 56G corresponds to the third layer.

First, a comparative example is shown with reference to fig. 9. Fig. 9 is a time chart of a comparative example, in which reference numerals denote a cluster unit, a film forming chamber, a connecting chamber, a substrate transfer robot, and the like shown in fig. 1.

In the comparative example, the film formation of both the first layer and the second layer was performed in the same unit CU 1. That is, after the first layer is formed on the substrate S1 in the film forming chamber EV11, the substrate S1 is transferred from the film forming chamber EV11 to the EV12 by the transfer robot RR 1. Then, after a second layer is formed in the film forming chamber EV12 so as to overlap the first layer, the substrate S1 is transferred from the film forming chamber EV12 to the buffer chamber BC1 by the transfer robot RR 1. Next, the transfer robot RC1 in the connection chamber CN1 transfers the substrate S1 from the buffer chamber BC1 to the passage chamber PS1, and the alignment of the substrate S1 is performed in the passage chamber PS 1. Then, the film thickness of the first layer is measured in the passage chamber PS1 by the film thickness measuring unit 310. When the film thickness of the first layer is different from the target value, the film thickness control unit 350 performs feedback control for the film forming chamber EV11 in the unit CU1, and adjusts the film forming conditions for the subsequent substrate S2. On the other hand, the substrate S1 after the film thickness measurement is transferred from the passage chamber PS1 to the film forming chamber EV21 of the second unit CU2 by the transfer robot RR2, and the third layer is formed.

By performing such feedback control, the film thickness of the first layer in the subsequent substrate S2 can be corrected to an appropriate value. However, in such a sequence, if film thickness measurement of the first layer of the preceding substrate is not waited, film formation of the first layer of the next substrate cannot be started, and thus it is difficult to improve the throughput of the apparatus.

Therefore, in the present embodiment, the following structure is adopted: the film formation sequence is set so that the first layer and the second layer are formed by different units, the film thickness of the first layer is measured in the connecting chamber immediately after the film formation of the first layer, and the feedback control of the first layer is performed based on the measurement result.

The present embodiment is described with reference to fig. 10. Fig. 10 is a timing chart of an embodiment. First, a first layer is formed in the first film forming chamber EV11 in the first unit CU1, and the substrate S1 is transferred from the film forming chamber EV11 to the buffer chamber BC1 by the transfer robot RR 1. That is, the substrate S1 after the film formation of the first layer (common layer) in the first film formation chamber EV11 is transferred to the connection chamber without passing through another film formation chamber. In the present embodiment, the first unit CU1 is configured such that the other film forming chambers (the film forming chamber EV12 and the film forming chamber EV 14) are disposed downstream in the flow direction of the substrate in the first film forming chamber EV11, and the other layers can be formed by these film forming chambers, but in the present embodiment, even in such a device configuration, the substrate S1 is not transferred to the downstream connection chamber via the other film forming chambers, and the film forming process is not performed in the other film forming chambers (the film forming chamber EV12 and the film forming chamber EV 14). Next, the transfer robot RC1 in the connection chamber CN1 transfers the substrate S1 from the buffer chamber BC1 to the passage chamber PS1, and the alignment of the substrate S1 is performed in the passage chamber PS 1. The film thickness of the first layer is measured in the passage chamber PS1 by the film thickness measuring unit 310. When the film thickness of the first layer is different from the target value, the film thickness control unit 350 performs feedback control for the first film formation chamber EV11 in the first unit CU 1. For example, the scanning speed of the first film formation chamber EV11 may be reduced when the film thickness of the first layer is smaller than the target value, whereas the scanning speed of the first film formation chamber EV11 may be increased when the film thickness of the first layer is larger than the target value. On the other hand, the substrate S1 after the film thickness measurement is transferred from the passage chamber PS1 to the second film forming chamber EV21 of the second unit CU2 by the transfer robot RR2, and the second layer is formed. Then, the transfer robot RR2 transfers the substrate S1 from the film forming chamber EV21 to the EV22, and the third layer is formed. When the second film is formed in the second film forming chamber EV21 or the third film is formed in the third film forming chamber EV22 with respect to the substrate S1, feedforward control may be performed to control the film forming conditions of the second film forming chamber EV21 or the third film forming chamber EV22 based on the film thickness of the first layer measured in the passage chamber PS 1. Thus, even when the film thickness of the first layer of the substrate S1 is different from the target value, the optical path length of each light emitting element (each sub-pixel) is adjusted by adjusting the film thickness of the film formed after the first layer, so that the color purity of the light emitting element can be improved.

According to the feedback control of this embodiment, since the film thickness measurement and feedback of the first layer are performed immediately after the film formation of the first layer, the timing of the start of the film formation of the subsequent substrate S2 can be made earlier than in the order of the comparative example. Therefore, the throughput of the device can be improved, and high productivity can be achieved.

The embodiments described herein are merely examples. For example, the unit for forming the first layer and the unit for forming the second layer do not need to be adjacent to each other via the connection chamber, and may be separated as in the units CU1 and CU3 of fig. 1. That is, a connection chamber in which the film thickness measuring section 310 is provided may be arranged between the upstream side unit (for example, CU 1) and the downstream side unit (for example, CU 3). However, even in this case, from the viewpoint of productivity, it is preferable that the film thickness measuring section 310 is provided in a connection chamber connected immediately after the unit for performing the film formation of the first layer.

In addition, when a plurality of layers are stacked, the film thickness of the lower first layer can be controlled with high accuracy. This is extremely advantageous in the case of forming a common layer requiring precision. In general, the common layer such as the hole transport layer is formed thicker than the light-emitting layer formed by dividing each sub-pixel. For example, to share layers The left and right film thicknesses are formed to form red, blue and green layers (layers obtained by laminating a single layer of each color light-emitting layer or a layer obtained by laminating light-emitting layers of each color and adjustment layers)The left and right film thicknesses are formed. Thus, the common layer is formed to have a thickness of about 3 to 5 times larger than each of the red, blue, and green layers. When the common layer is formed thick in this way, even if the feedforward control is performed as described above when the film thickness of the common layer deviates from the target value, the film thickness of each of the red, blue, and green partial coatings formed on the common layer is adjusted to adjust the entire film thickness, and sometimes cannot be adjusted due to the deviation of the film thickness of the common layer from the target value. Further, since it is necessary to adjust the film thickness of each of the red, blue, and green partial coatings, control is complicated, and the takt time of the entire device may be increased depending on the situation. In such a case, as in the present embodiment, the layer is formed in the common layerThe film thickness is measured immediately after the film formation is completed, and the film formation of the common layer is feedback-controlled based on the measurement result, whereby substrates which are defective substrates due to unadjusted feedforward control of the subsequent film formation chamber can be reduced, and the yield can be improved.

Example 2

In example 2, first, a first layer is formed in the first film forming chamber EV12 in the first unit CU1, and the substrate S1 is transferred from the film forming chamber EV12 to the buffer chamber BC1 by the transfer robot RR 1. Next, the transfer robot RC1 in the connection chamber CN1 transfers the substrate S1 from the buffer chamber BC1 to the passage chamber PS1, and the alignment of the substrate S1 is performed in the passage chamber PS 1. Then, the film thickness of the first layer is measured in the passage chamber PS1 by the film thickness measuring unit 310. The film thickness control unit 350 performs feedforward control for the second film forming chamber EV21 in the second unit CU2 based on the film thickness information of the first layer acquired in the passage chamber PS 1.

Specific examples of film thickness control by the film thickness control system will be described. In the lamination process in which the first layer is formed and then the second layer is formed on the first layer in an overlapping manner, the film thickness is controlled so that the thickness of the first layer and the second layer added to each other becomes a target value.

First, a comparative example is shown with reference to fig. 11. Fig. 11 is a time chart of a comparative example, in which reference numerals denote a cluster unit, a film forming chamber, a connecting chamber, a substrate transfer robot, and the like shown in fig. 1.

In the comparative example, the film formation of both the first layer and the second layer was performed in the same unit CU 1. That is, after the first layer is formed on the substrate S1 in the film forming chamber EV11, the substrate S1 is transferred from the film forming chamber EV11 to the EV12 by the transfer robot RR 1. Then, after a second layer is formed in the film forming chamber EV12 so as to overlap the first layer, the substrate S1 is transferred from the film forming chamber EV12 to the buffer chamber BC1 by the transfer robot RR 1. Next, the transfer robot RC1 in the connection chamber CN1 transfers the substrate S1 from the buffer chamber BC1 to the passage chamber PS1, and the alignment of the substrate S1 is performed in the passage chamber PS 1. Then, the film thickness of the first layer and the second layer is measured by the film thickness measuring unit 310 in the passage chamber PS 1. When the total film thickness of the first layer and the second layer is different from the target value, the film thickness control unit 350 performs feedback control for the film forming chambers EV11 and EV12 in the unit CU1, and adjusts the film forming conditions for the subsequent substrate S2.

By performing such feedback control, the total film thickness of the first layer and the second layer can be made close to the target value. However, in this method, although a good film thickness can be obtained on the substrate (after the substrate S2) subjected to the film formation process after the substrate S1 having a film thickness is measured, the film thickness of the substrate S1 itself cannot be corrected, and thus the substrate S1 may become a defective substrate.

Therefore, in the present embodiment, the following structure is adopted: the film formation sequence is set so that the first layer and the second layer are formed by different units, the film thickness of the first layer is measured in the connecting chamber after the film formation of the first layer and before the film formation of the second layer, and the film thickness of the second layer is controlled (corrected) based on the measurement result.

The present embodiment is described with reference to fig. 12. Fig. 12 is a timing chart of an embodiment. First, a first layer is formed in the first film forming chamber EV12 in the first unit CU1, and the substrate S1 is transferred from the film forming chamber EV12 to the buffer chamber BC1 by the transfer robot RR 1. Next, the transfer robot RC1 in the connection chamber CN1 transfers the substrate S1 from the buffer chamber BC1 to the passage chamber PS1, and the alignment of the substrate S1 is performed in the passage chamber PS 1. Then, the film thickness of the first layer is measured in the passage chamber PS1 by the film thickness measuring unit 310. When the film thickness of the first layer is different from the predetermined value, the film thickness control unit 350 performs feedforward control for the second film formation chamber EV21 in the second unit CU 2. At this time, the film thickness control unit 350 controls the film formation conditions of the second film formation chamber EV21 so that the total film thickness of the first layer and the second layer added becomes a target value. For example, when the film thickness of the first layer is smaller than a predetermined value, the scanning speed of the second film formation chamber EV21 may be decreased in order to increase the film thickness of the second layer, whereas when the film thickness of the first layer is larger than a predetermined value, the scanning speed of the second film formation chamber EV21 may be increased in order to decrease the film thickness of the second layer.

According to the feedforward control of this embodiment, the film thickness of the substrate S1 itself whose film thickness is measured can be adjusted (corrected), so that the occurrence of defective substrates can be suppressed as much as possible, and the yield can be improved.

The feedforward control of the present embodiment can be preferably used in a case where two or more layers are selectively stacked in a region where a specific sub-pixel is formed, for example, as in the red layer 56R shown in fig. 7 (c). That is, the film formation of the lower layer 56R1 (first layer) and the film formation of the upper layer 56R2 are performed by different units, and the film formation conditions of the upper layer 56R2 are adjusted based on the measurement result of the lower layer 56R1, whereby the film thickness of the entire red layer 56R is brought close to the target value.

The embodiments described herein are merely examples. For example, when one functional layer is formed of three layers, the lower two layers can be formed by the first unit, and the film forming condition of the uppermost layer in the second unit can be controlled based on the measurement result of the film thicknesses of the lower two layers. The unit for forming the first layer and the unit for forming the second layer do not need to be adjacent to each other via the connection chamber, and may be separated as in the units CU1 and CU3 of fig. 1. That is, a connection chamber in which the film thickness measuring section 310 is provided may be arranged between the upstream side unit (for example, CU 1) and the downstream side unit (for example, CU 3). The first layer deposition process and the second layer deposition process do not need to be performed continuously, and another layer deposition process may be performed at a position not overlapping the first layer between the first layer deposition process and the second layer deposition process.

According to the film forming apparatus (electronic device manufacturing apparatus) of the present embodiment, when a plurality of layers are stacked, the film forming conditions of the upper second layer are adjusted based on the film thickness of the lower first layer, whereby the total film thickness of the two layers can be controlled with high accuracy. Thus, productivity and yield can be improved.

According to the feedforward control of example 2, the film thickness of the substrate S1 itself whose film thickness is measured can be adjusted (corrected), so that the occurrence of defective substrates can be suppressed as much as possible, and the yield can be improved. Further, since the film thickness measurement is performed by the passage chamber PS1, the influence on the manufacturing tact can be reduced, as in example 1.

The embodiments described herein are merely examples. For example, the feedforward control in embodiment 2 may be performed in a film forming chamber of a unit downstream of the second unit CU 2. Further, the feed-forward control may be performed on the downstream one of the film forming chambers based on the plurality of pieces of film thickness information acquired in the plurality of passage chambers, respectively.

The feedback control in example 1 may be performed by, for example, feeding back the film formation chamber EV11 and the film formation chamber EV12 from the passage chamber PS 1. That is, measurement patches are formed in the film forming chambers EV11 and EV12, respectively, and film thickness information obtained from the measurement patches is fed back to the film forming chambers EV11 and EV12, respectively. In this case, by providing two film thickness measuring units in advance at positions corresponding to the respective measuring patches in the passage chamber PS1, the film thickness can be evaluated simultaneously in parallel. When the layers of the same material are formed in the film forming chambers EV11 and EV12, the total film thickness information obtained by overlapping the first layer and the second layer can be used for feedback.

In addition, when a plurality of layers are formed to overlap each other in a plurality of units, it may be effective to feed back the total film thickness information obtained after the film formation of the outermost layer to the film forming chamber of the most upstream unit.

< others >

The above embodiments are merely illustrative examples of the present invention. The present invention is not limited to the configuration of the above embodiment, and various modifications can be adopted. For example, the number of the cluster units provided in the electronic device manufacturing apparatus may be any number as long as it is two or more. The configuration of each cluster unit is also arbitrary, and the number of film forming chambers and the number of mask chambers may be appropriately set according to the application. In the above embodiment, the apparatus configuration capable of performing the film formation processing in two paths, i.e., the film formation chambers EVx1 to EVx and the film formation chambers EVx3 to EVx4, is shown, but the apparatus configuration may be one path or three or more paths. In the film forming apparatus having the plurality of paths, the film thickness measuring sections are provided in the connecting chamber, so that the number of film thickness measuring sections can be reduced, and the cost and the apparatus size can be reduced. The film thickness measuring section may be provided only in a part of the connection chambers, and need not be provided in all of the connection chambers of the electronic device manufacturing apparatus. That is, the film thickness measuring section may be provided only at a portion where highly precise control of the film thickness is required. In the above embodiment, the reflection spectroscopic film thickness meter is used, but other film thickness meters (for example, spectroscopic ellipsometer) may be used.

Claims

1. A film forming apparatus, characterized in that,

the film forming apparatus includes:

A first measurement unit provided in the connection chamber at least in part for measuring a thickness of a film formed on the substrate,

the connecting chamber has:

a buffer chamber capable of accommodating a plurality of substrates;

a swirl chamber for changing an orientation of the substrate;

a passage chamber for delivering a substrate to the second unit;

a position acquisition means for acquiring information on a position of a substrate disposed inside the passage chamber in the passage chamber; and

A moving mechanism that moves the substrate inside the passage chamber based on the information of the position acquired by the position acquisition mechanism,

the at least a portion of the first measuring unit is provided in the passage chamber.

2. The film forming apparatus according to claim 1, wherein,

the film forming apparatus includes an alignment mechanism that adjusts a relative position between the substrate and the mask.

3. The film forming apparatus according to claim 2, wherein,

the moving mechanism moves the substrate to a measurement position based on the information of the position,

after the movement of the substrate by the movement mechanism is performed, the first measurement unit measures the thickness of the film formed on the substrate.

4. The film forming apparatus according to claim 1, wherein,

the first measuring unit optically measures the thickness of a film formed on the substrate.

5. The film forming apparatus according to claim 1, wherein,

the film forming apparatus includes a second measuring unit provided in the first film forming chamber at least a part of which measures a thickness of a film formed on a substrate accommodated in the first film forming chamber.

6. The film forming apparatus according to claim 1, wherein,

the film forming apparatus includes a crystal oscillation type film forming rate monitor, at least a part of which is provided in the first film forming chamber, and measures the amount of the film forming material discharged from the evaporation source.

7. The film forming apparatus according to claim 1, wherein,

the film forming apparatus includes a control unit that controls at least one of a film forming condition of the first film forming chamber and a film forming condition of the second film forming chamber based on the thickness of the film measured by the first measuring unit.

8. The film forming apparatus according to claim 5, wherein,

the film forming apparatus further includes a control unit that controls at least one of a film forming condition of the first film forming chamber and a film forming condition of the second film forming chamber based on the thickness of the film measured by the first measuring unit and the thickness of the film measured by the second measuring unit.

9. The film forming apparatus according to claim 6, wherein,

the film forming apparatus further includes a control unit that controls at least one of a film forming condition of the first film forming chamber and a film forming condition of the second film forming chamber based on the thickness of the film measured by the first measuring unit and the amount of the deposition material discharged measured by the deposition rate monitor.

10. The film forming apparatus according to claim 1, wherein,

the substrate has an element region where an element is formed and a measurement region different from the element region,

in the film formation by the first film formation chamber, the first film is formed in the element region and the measurement region,

the first measurement unit measures the thickness of the first film formed in the measurement region.

11. The film forming apparatus according to claim 1, wherein,

the buffer chamber, the swirl chamber, and the passage chamber are disposed in this order from the upstream side in the conveyance path,

the passage chamber is disposed adjacent to a cluster-type cell on a downstream side of the two cluster-type cells connected by the connection chamber.

12. The film forming apparatus according to claim 1, wherein,

the two cluster units connected by the connection chamber are each provided with a substrate transfer mechanism for transferring a substrate,

the substrate transfer mechanism of the cluster type cell on the upstream side of the two cluster type cells feeds the substrate into the buffer chamber,

the transfer robot provided in the whirling chamber sends the substrate out of the buffer chamber, changes the orientation of the substrate, sends the substrate into the passage chamber,

The substrate transfer mechanism of the cluster type cell on the downstream side of the two cluster type cells sends out the substrate arranged in the passage chamber.

13. The film forming apparatus according to claim 1, wherein,

the connecting chamber has:

a position acquisition means for acquiring information on the position of the substrate disposed in the connection chamber in the passage chamber; and

And a moving mechanism that moves the substrate inside the passage chamber based on the information of the position acquired by the position acquisition mechanism.

14. The film forming apparatus according to claim 13, wherein,

15. The film forming apparatus according to claim 1, wherein,

after the preceding substrate accommodated in the passage chamber is sent out from the passage chamber, the subsequent substrate is sent into the passage chamber.

16. The film forming apparatus according to claim 1, wherein,

The number of substrates that can be accommodated in the buffer chamber is larger than the number of substrates that can be accommodated in the passage chamber.

17. The film forming apparatus according to any one of claims 1 to 10, wherein,

film forming conditions of the second film forming chamber are controlled based on the thickness of the first film measured by the first measuring section.

18. The film forming apparatus according to claim 17, wherein,

the substrate has:

a first pixel region formed with a plurality of first light emitting elements that emit light of a first wavelength, respectively; and

A second pixel region formed with a plurality of second light emitting elements each emitting light of a second wavelength different from the first wavelength,

in the film formation by the first film formation chamber, the first film is formed in the first pixel region, and the first film is not formed in the second pixel region,

in the film formation by the second film formation chamber, the second film is formed in the first pixel region, and the second film is not formed in the second pixel region.

19. The film forming apparatus according to claim 17, wherein,

Film forming conditions of the second film forming chamber are controlled based on the thickness of the first film measured by the first measuring section so that the thickness obtained by adding the first film and the second film is included in a predetermined range.

20. The film forming apparatus according to claim 19, wherein,

the first film constitutes a hole transporting layer or an electron blocking layer,

the second film constitutes a light emitting layer.

21. The film forming apparatus according to claim 18, wherein,

the first film constitutes a light-emitting layer,

the second film constitutes an electron transport layer or a hole blocking layer.

22. The film forming apparatus according to claim 18, wherein,

the substrate has a measurement region different from the first pixel region and the second pixel region,

in the first film forming chamber, forming the first film in the measurement region,

23. The film forming apparatus according to any one of claims 1 to 10, wherein,

film forming conditions of the first film forming chamber are controlled based on the thickness of the first film measured by the first measuring section.

24. The film forming apparatus according to claim 23, wherein,

at least a part of the first measuring unit is disposed in the connection chamber connected to the first unit.

25. The film forming apparatus according to claim 24, wherein,

the first transfer mechanism transfers the substrate on which the first film is formed from the first film forming chamber to the connecting chamber without passing through the other film forming chambers.

26. The film forming apparatus according to claim 23, wherein,

the substrate has:

in the film formation by the first film formation chamber, the first film is formed in the first pixel region and the second pixel region, respectively,

27. The film forming apparatus according to claim 26, wherein,

The first film constitutes a hole transport layer or an electron blocking layer of each of the first light emitting element and the second light emitting element,

the second film constitutes a light-emitting layer of the first light-emitting element.

28. The film forming apparatus according to claim 26, wherein,

the film forming apparatus further includes a third film forming chamber that forms a third film in the second pixel region and does not form the third film in the first pixel region.

29. The film forming apparatus according to claim 28, wherein,

the second film constitutes a light emitting layer of the first light emitting element,

the third film constitutes a light-emitting layer of the second light-emitting element.

30. A method for manufacturing an electronic device, characterized in that,

the manufacturing method of the electronic device comprises the following steps:

a step of forming the first film by using the film forming apparatus according to claim 1; and

And forming the second film using the film forming apparatus.

31. A film forming method, characterized in that,

the film forming method comprises the following steps:

And forming the second film using the film forming apparatus.

32. A method of manufacturing an electronic device, wherein,

the method for manufacturing an electronic device using the film forming method according to claim 31.