CN222544647U

CN222544647U - An online measurement device for OLED vapor deposition film thickness

Info

Publication number: CN222544647U
Application number: CN202323643601.8U
Authority: CN
Inventors: 李有亮; 奉洛阳; 刘世刚
Original assignee: Chengdu Xili Technology Co ltd
Current assignee: Chengdu Xili Technology Co ltd
Priority date: 2023-12-29
Filing date: 2023-12-29
Publication date: 2025-02-28
Anticipated expiration: 2033-12-29

Abstract

The utility model relates to the technical field of OLED display device manufacturing, and discloses an online measurement device for the thickness of an OLED evaporated film layer, the device comprising a vacuum chamber, a measuring lens, a substrate, an evaporated film layer, a chamber alignment mechanism, an electrostatic chuck and an auxiliary top PIN arranged in the vacuum chamber, and a spectrometer and a light source arranged outside the vacuum chamber; the evaporated film layer is deposited on the substrate, the substrate is supported on the chamber alignment mechanism, the measuring lens is located below the evaporated film layer, the spectrometer and the light source are connected to the measuring lens through an optical fiber, the electrostatic chuck is used to adsorb the substrate, and the auxiliary top PIN is used to lift the substrate. The utility model can measure the thickness of each evaporated film layer online, and uses an electrostatic chuck to adsorb the back of the substrate, and after the glass substrate is completely sucked flat, the thickness measurement of the evaporated film is completed, which solves the problem that the SR cannot be measured due to the droop of the substrate due to gravity.

Description

OLED evaporation coating film thickness on-line measuring device

Technical Field

The utility model relates to the technical field of manufacturing of OLED display devices, in particular to an on-line measuring device for thickness of an OLED evaporation film.

Background

The vapor deposition process is used as a core process of the OLED panel display industry, plays a decisive role in the production yield of the whole panel, the vapor deposition machine has the role of evaporating luminescent materials and other functional materials to specific positions of a target substrate in an ultrahigh vacuum environment in a heating mode, the thin film deposited on the substrate is particularly thin due to the special principle of OLED luminescence, the thickness of the thin film is about 0.1-12 nm, the accuracy of the deposited thin film on the substrate is particularly important for an OLED luminescent device, and how to control the accuracy and stability of the film thickness of the thin film in the production process is the most important factor of device success.

Because the light-emitting materials and the functional materials adopted by the OLED light-emitting device are easily oxidized by water, oxygen or other gases, the thickness of the thin film is measured by adopting an optical non-contact method in the industry. The mature method is to measure the thickness of the film by adopting an ellipsometer (SE), the SE measuring principle is that incident light irradiates the surface of the film at 45 degrees, light reflected by a substrate after penetrating the film exits to a lens at 45 degrees, the phase angle of light waves changes after the light passes through the film, the changing size is a function of the thickness of the film, and the thickness of the film can be obtained by a fitting mode. Therefore, the SE measurement mode needs two 45 ° lenses to collect spectrum information, and the object to be measured must be placed on the marble working table during measurement, and the vibration of the device also affects the measurement accuracy, so the SE measurement adopted in the traditional method needs to make a precise measurement device, and the device needs to protect the measured product from being affected by water, oxygen or other gas components, and because the measurement environment needs as little vibration as possible, the ultra-high vacuum atmosphere cannot be adopted, and only pure nitrogen or other inert gas environments can be adopted, which results in great cost for the SE measurement.

Meanwhile, as the vacuum environment is adopted for film deposition and the nitrogen environment of SE equipment is adopted for measurement, when the chambers are interacted before the measurement of the product, the chamber atmosphere is required to be replaced, and the long time required for the measurement of the product is determined, so that the conventional solution is to only perform spot check on the deposited film thickness, and the film thickness of each product cannot be monitored on line, thereby greatly possibly causing defective products.

The invention patent with publication number CN115702485A discloses a scheme for in-situ measurement of a thin film through a transparent crystal and a transparent substrate in the wall of a processing cavity, wherein the scheme can monitor the thickness of a deposited film in real time, but for a large-size substrate used in the manufacturing process of an OLED display panel, deformation of the substrate due to sagging of the substrate, which causes no ideal specular reflection in the measuring process, the problem that a measuring lens cannot measure occurs, and the measuring accuracy is affected.

Disclosure of utility model

Aiming at the problems and defects existing in the prior art, the utility model provides an on-line measuring device for the thickness of an OLED vapor deposition film, which adopts a reflection spectrum method to realize the detection of the thickness of the OLED panel vapor deposition film, adopts an electrostatic chuck to solve the problem of substrate deformation due to weight sagging, integrates a measuring unit in a vacuum chamber, and can realize the film thickness detection of each product.

In order to achieve the above object, the present utility model has the following technical scheme:

The utility model provides an on-line measuring device for the thickness of an OLED vapor deposition film layer, which mainly comprises a vacuum chamber, wherein a measuring lens, a substrate and the vapor deposition film layer are arranged in the vacuum chamber, a spectrometer and a light source which are connected with the measuring lens are arranged outside the vacuum chamber, the vapor deposition film layer is deposited on the substrate, the measuring lens is positioned below the vapor deposition film layer, the spectrometer and the light source are connected with the measuring lens in the chamber through an optical fiber, and the device further comprises:

A chamber alignment mechanism disposed within the vacuum chamber for supporting the substrate;

An electrostatic chuck disposed in the vacuum chamber for chucking a substrate, and

An auxiliary top PIN disposed in the vacuum chamber for lifting up the substrate.

In the testing process, the measuring lens vertically irradiates the light beam from the light source to the measuring point of the vapor deposition film layer, receives the light reflected by the film surface and the light reflected by the substrate surface, focuses the light and then transmits the light to a spectrometer outside the chamber through an optical fiber, and further, the spectrometer converts the signal intensity of a spectrum into an electric signal and transmits the electric signal to data processing equipment such as a computer connected with the spectrometer through a communication line to obtain the thickness value of the vapor deposition film layer.

As a preferable mode of the utility model, the auxiliary top PIN is arranged on the chamber alignment mechanism.

As a preferable scheme of the utility model, the measuring lens is positioned on the chamber alignment mechanism.

As a preferable scheme of the utility model, the electrostatic chuck is provided with an ESC alignment mechanism, and an output end of the electrostatic chuck alignment mechanism extends into the vacuum chamber to be connected with the electrostatic chuck.

As a preferable scheme of the utility model, a magnetic fluid sealing unit is arranged between the output end of the ESC alignment mechanism and the vacuum chamber.

As a preferable scheme of the utility model, the vacuum chamber is provided with an optical fiber feed-through coupling flange for the optical fiber to pass through.

As a preferred scheme of the utility model, the device further comprises a sucker controller, the electrostatic sucker is connected with the sucker controller outside the vacuum chamber through a control wire, and a vacuum feed-through flange for the control wire to pass through is arranged on the shell of the vacuum chamber.

The utility model has the beneficial effects that:

1. According to the utility model, the measuring lens is arranged in the vacuum chamber which is the same as the deposition environment, the atmosphere in the chamber is not required to be replaced, the thickness of each evaporated film layer can be measured on line, the cost is reduced, and the measuring time is shortened.

2. According to the utility model, the back surface of the substrate is adsorbed by the electrostatic chuck, after the glass substrate is completely sucked and leveled, the ESC alignment mechanism carries the substrate to perform alignment, and after the alignment is completed, the on-line measurement of the thickness of the evaporated film can be realized, so that the problem that the measurement lens cannot measure due to the sagging deformation of the substrate by gravity is solved.

Drawings

The foregoing and the following detailed description of the utility model will become more apparent when read in conjunction with the following drawings in which:

FIG. 1 is a schematic diagram of an on-line measuring device of the present utility model;

FIGS. 2-5 are schematic diagrams illustrating the process of supporting the top PIN lift and the electrostatic chuck to adsorb a substrate according to the present utility model;

Fig. 6-7 are schematic views illustrating a substrate reset process according to the present utility model.

In the figure:

1. The device comprises a vacuum chamber, a chamber alignment mechanism, a measuring lens, a substrate, a spectrometer, an auxiliary top PIN, an electrostatic chuck, an ESC alignment mechanism, a magnetic fluid sealing unit, an optical fiber feed-through coupling flange, a chuck controller, a vacuum feed-through flange, a data processing device and data processing equipment, wherein the vacuum chamber, the chamber alignment mechanism, the measuring lens, the substrate, the spectrometer, the auxiliary top PIN, the electrostatic chuck, the ESC alignment mechanism, the magnetic fluid sealing unit, the optical fiber feed-through coupling flange, the chuck controller, the vacuum feed-through flange and the data processing device.

Detailed Description

The thickness of the film is measured by adopting an optical non-contact method, the mature method is to measure the thickness of the film by adopting an ellipsometer (SE), the SE measurement principle is that incident light irradiates the surface of the film through 45 degrees, light reflected by a substrate after passing through the film exits to a lens at 45 degrees, the phase angle of light waves changes after passing through the film, the change size is a function of the thickness of the film, the thickness of the film can be obtained by a fitting mode, so that the measurement mode of the SE needs two lenses at 45 degrees to finish the acquisition of spectral information, and the measured object is required to be placed on a marble working table surface during measurement, the vibration of equipment also influences the measurement precision. This results in a significant cost for using SE measurements.

Based on the above, the utility model provides a novel on-line measuring device for the thickness of an OLED evaporation film layer, the utility model adopts a method of vertical light incidence, a detection light beam output by a light source vertically enters the surface of a film at 90 degrees, after the light passes through the surface of the film, the light is reflected back on the surface of a substrate, the coupling light spectrum information of the reflected light of the film and the reflected light of the substrate is obtained through analysis of a spectrometer, the film thickness of the film can be fitted, and the detailed theory can refer to the reflection spectrum method to measure the film principle. Because the optical signal transmission of 90 degrees is adopted, the incident light and the reflector lens can be integrated together, the lens is integrated in the vacuum chamber through the design of the lens mechanism, and finally, the spectrum signal obtained by measuring the lens in the vacuum chamber is transmitted to the spectrometer outside the vacuum chamber through the optical fiber, so that the fitting of the film thickness can be carried out.

The utility model adopts a reflection spectrum method to realize the detection of the thickness of an evaporation film in the OLED panel industry, solves the problem of sagging of a substrate due to weight by adopting an electrostatic chuck (ESC), integrates a measuring unit in a vacuum chamber, and can realize the detection of the film thickness of each product, and the specific scheme is as follows:

Referring to fig. 1 of the drawings, which is a schematic structural diagram of an exemplary measuring apparatus according to an aspect of the disclosure, the apparatus mainly includes a vacuum chamber 1, a measuring lens 3, a substrate 4 and a vapor deposition film layer disposed in the vacuum chamber 1, and a spectrometer and a light source disposed outside the vacuum chamber 1, wherein the vapor deposition film layer is deposited on the substrate 4, the measuring lens 3 is located directly below the vapor deposition film layer, and the spectrometer 5 and the light source are connected with the measuring lens 3 in the chamber through an optical fiber, and further, the measuring apparatus further includes:

A chamber alignment mechanism 2, wherein the chamber alignment mechanism 2 is arranged in the vacuum chamber 1 and is used for supporting a substrate 4 deposited with a vapor deposition film layer;

An electrostatic chuck 6, the electrostatic chuck 6 being disposed in the vacuum chamber 1 and above the substrate 4, for sucking the substrate 4;

An auxiliary top PIN7, the auxiliary top PIN7 is disposed in the vacuum chamber 1 and located below the substrate 4, and is used for lifting the substrate 4 supported on the chamber alignment mechanism 2.

In the depicted embodiment, the chamber alignment mechanism 2 is in contact with four corners of the substrate 4 through four top posts provided on the top surface in a four-point supporting manner, so as to support and fix the substrate 4.

In the embodiment depicted, the measuring lens 3 and the auxiliary top PIN7 are arranged on the chamber-alignment mechanism 2, wherein the auxiliary top PIN7 is distributed at four corners of the substrate 4.

In various embodiments of the present utility model, the light source and the spectrometer 5 may be packaged together in a single structure to form a whole, or may be a separate structure, and the present utility model is not limited thereto.

In various embodiments of the present utility model, the chamber alignment mechanism 2 generally further has a displacement adjustment function, which can adjust the position of the substrate 4 supported thereon in the chamber, thereby achieving an alignment effect. The displacement adjustment includes a horizontal displacement adjustment in the front-back and left-right directions and a vertical displacement adjustment in the vertical direction. It should be noted that, the chamber alignment mechanism 2 may use an existing three-dimensional motion platform to implement the displacement adjustment function, and the three-dimensional motion platform is in the prior art and is not developed in detail here. In the depicted embodiment, the chamber-aligning mechanism 2 is typically mounted on the bottom wall of the vacuum chamber 1.

In the utility model, because the vapor deposition process adopts a bottom-up deposition mode, the measuring lens 3 is arranged under the vapor deposition film layer, the lens has the functions of focusing the emergent light of the light source through the lens, accurately inputting the focused emergent light onto the measuring point of the film layer on the substrate, transmitting the reflected light information of the spectrum to the spectrometer through the lens, converting the signal intensity of the spectrum into an electric signal by the spectrometer, transmitting the electric signal to a computer end, and fitting the spectrum intensity signal through a relevant film thickness fitting algorithm, thus obtaining the thickness value of the vapor deposition film layer. In the depicted embodiment, the film thickness fitting algorithm fits the spectral intensity signals as prior art and is not developed in detail herein.

Further, in the present utility model, since the measuring lens 3 is located in the vacuum chamber 1, and the spectrometer 5 and the light source are both located in the atmospheric environment, a vacuum sealing flange is required to be adopted, and the transmission of the spectrum signal is realized through an optical fiber feed-through. That is, in the present utility model, an optical fiber feed-through coupling flange 10 through which an optical fiber passes is provided on a sidewall of the vacuum chamber 1, and the optical fiber passes through the flange and is connected to the measuring lens 3 in the chamber.

Still further, in the present utility model, the electrostatic chuck 6 is generally mounted on the ceiling wall of the chamber, connected to a chuck controller 11 outside the vacuum chamber 1 by a control line, and a vacuum feed-through flange 12 through which the control line passes is provided on the ceiling wall of the vacuum chamber 1.

In the utility model, in order to better and more accurately realize the measurement of the thickness of the film, the outgoing light beam output by the light source can be correctly incident on the measurement point of the film, the electrostatic chuck is also provided with an ESC alignment mechanism 8, and the output end of the alignment mechanism extends into the vacuum chamber 1 to be connected with the electrostatic chuck 6. The ESC alignment mechanism 8 can adjust the horizontal displacement of the electrostatic chuck 6 in the chamber, adjust the vertical displacement in the vertical direction and drive the electrostatic chuck 6 to rotate in the horizontal direction, so as to adjust the angle of the electrostatic chuck, and finally realize the alignment effect of the substrate 4.

In some embodiments, a magnetic fluid sealing unit 9 is disposed between the output end of the ESC alignment mechanism 8 and the vacuum chamber. The function of the magnetic fluid sealing unit 9 is to transfer the rotary motion into the sealed container, often for vacuum sealing.

In the present utility model, in particular, in order to reduce the cost and increase the productivity, it is generally preferable to use glass as the substrate increases in size, and the glass substrate is thin, and since the middle of the glass is the display area of the film layer and cannot be directly contacted, a blank area is left at the edge position of the glass, and the substrate is horizontally placed on the top column of the chamber alignment mechanism 2, but since the substrate cannot be supported on the front surface, the glass is deformed. However, for the principle of measuring film thickness by reflected light, the reflected light must be irradiated vertically to receive the spectrum signal, so the utility model adopts the electrostatic chuck 6 to adsorb the back surface of the substrate (the surface on which the vapor deposition film layer is not deposited), after the glass substrate is completely absorbed, the ESC alignment mechanism 8 carries the substrate to perform alignment, and the measurement can be realized after the alignment is completed.

Referring to fig. 2-7 of the specification, a specific measurement process of the measurement device is shown in the schematic drawing, and the main process is as follows during the test:

Step 1. Referring to fig. 2 of the specification, a product is carried from a process chamber into a vacuum chamber 1, and a chamber alignment mechanism 2 in the chamber performs alignment, and during the alignment, an ESC (electrostatic chuck 6) is lowered.

And 2, referring to fig. 3 of the specification, at the moment, the auxiliary top PIN7 rises to jack up the glass substrate to be in contact with the ECS, and the ESC is electrified to start to absorb the glass substrate.

It should be noted that the ESC can only slowly adsorb glass upwards through one side when adsorbing the substrate, if during the adsorption process, the two sides of the glass are adsorbed first, and during the adsorption process, the glass substrate deforms from two sides to the middle, which can cause glass fragments.

And 3, referring to fig. 4 of the specification, the auxiliary top PIN7 is lowered, and the ESC adsorbs the glass substrate to perform alignment.

And 4, referring to figure 5 of the specification, after ESC alignment is completed, the measuring lens 4 collects optical signals and transmits the signals to the spectrometer for measurement through an optical fiber.

And 5, after the measurement is completed, the auxiliary top PIN7 is lifted and connected back to the glass substrate, and in the process, the top PINs at two sides can be lifted simultaneously.

And 6, lifting the electrostatic chuck 6, aligning the equipment receiving machine, and waiting for the glass substrate to be carried out.

Through the process, in the measuring process, the detection light beam output by the light source vertically enters the surface of the film through the measuring lens, and then the reflected light is vertically irradiated in the measuring lens, so that the problem that the measuring lens cannot accept light signals due to the fact that the large-size substrate sags and deforms under the action of gravity and cannot be measured can be solved.

In the description of the present utility model, it should be understood that the terms "center," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, merely to facilitate describing the present utility model and simplify the description, and do not indicate or imply that the devices or elements being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the scope of the present utility model.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected through an intermediate medium, or in communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The foregoing description is only a preferred embodiment of the present application and is not intended to limit the application in any way, but any simple modification, equivalent variation, etc. of the above embodiment according to the technical substance of the present application falls within the scope of the present application.

Claims

1. An online measurement device for the thickness of an OLED evaporated film layer, comprising: a vacuum chamber (1), a measuring lens (3), a substrate (4) and an evaporated film layer arranged in the vacuum chamber (1), and a spectrometer (5) and a light source arranged outside the vacuum chamber (1); wherein the evaporated film layer is deposited on the substrate (4), the measuring lens (3) is located below the evaporated film layer, and the spectrometer (5) and the light source are connected to the measuring lens (3) via an optical fiber, and the device is characterized in that it also comprises:

A chamber alignment mechanism (2) disposed in the vacuum chamber (1) and used for supporting a substrate (4);

an electrostatic chuck (6) disposed in the vacuum chamber (1) for adsorbing the substrate (4); and

An auxiliary lifting PIN (7) is arranged in the vacuum chamber (1) and is used for lifting the substrate (4).

2. The device for measuring the thickness of an OLED evaporated film layer online according to claim 1, characterized in that the auxiliary top PIN (7) is arranged on the chamber alignment mechanism (2).

3. The online measurement device for the thickness of an OLED evaporated film according to claim 1, characterized in that the measuring lens (3) is located on the chamber alignment mechanism (2).

4. The online measurement device for the thickness of an OLED evaporated film according to claim 1, characterized in that the electrostatic chuck (6) is provided with an ESC alignment mechanism (8), and an output end of the ESC alignment mechanism (8) extends into the vacuum chamber (1) and is connected to the electrostatic chuck (6).

5. The device for measuring the thickness of an OLED evaporated film layer online according to claim 4, characterized in that a magnetic fluid sealing unit (9) is provided between the output end of the ESC alignment mechanism (8) and the vacuum chamber (1).

6. The device for measuring the thickness of an OLED evaporated film online according to claim 1, characterized in that a fiber feed-through coupling flange (10) for the optical fiber to pass through is provided on the vacuum chamber (1).

7. An online measurement device for the thickness of an OLED evaporated film according to claim 1, characterized in that the electrostatic chuck (6) is connected to a chuck controller (11) outside the vacuum chamber (1) via a control line, and a vacuum feedthrough flange (12) is provided between the vacuum chamber (1) and the control line.