KR102648127B1 - Vertical Evaporation Point Nozzle Source - Google Patents

Abstract

The present invention seeks to present the structure of the nozzle and support member of a gradual evaporation source for vertical evaporation, and furthermore, the structure of the evaporation source, sensor, and substrate that can implement a vertical evaporation system.
In accordance with the above object, the present invention provides a point evaporation source having a bending nozzle that is bent so that evaporation from the point evaporation source has a path that allows the evaporation material to proceed nearly horizontally through a minimum number of reflections.

Description

{Vertical Evaporation Point Nozzle Source}

The present invention relates to an evaporation source that evaporates a material to create a thin film, and more specifically, to a gradual evaporation source and its system that can deposit a material while the substrate is placed vertically.

The vacuum deposition process refers to the process of heating a small piece of metal or non-metal in a vacuum and attaching the vapor to the surface of the substrate. The device for heating in the above process is called an evaporation source.

The evaporation source is largely comprised of a heater unit for heating the material, a crucible unit located inside the heater unit to contain the material, a nozzle unit through which the evaporated material is discharged from the crucible to the outside, and a nozzle unit located outside the heater unit so that heat generated from the heater unit is used. It is divided into a heat reflector part to minimize radiation to the outside. The deposition process involves placing the material to be evaporated in a crucible, transferring heat through a heater to evaporate the material inside the crucible, and the evaporated material is ejected through a nozzle of a certain shape and deposited on the substrate. The direction in which the material is evaporated inside the crucible and discharged to the outside and the discharge distribution of the evaporated material are determined by the shape and structure of the nozzle.

OLED, which is attracting attention as a next-generation display, is produced through the above deposition process. It is expected that the application field of the display will gradually expand from small displays such as mobile phones to medium-sized IT products such as tablets and laptops, and large products such as TVs.

In order to apply OLED displays to the above medium-sized IT products and large-sized products, it is necessary to enlarge the substrate. The system for producing small OLED displays uses a method of depositing OLED material upward while transferring the substrate horizontally to the ground. In enlarging a substrate, the existing horizontal transfer upward deposition method (horizontal deposition method) has its limitations due to sagging of the substrate due to gravity. As one of the ways to overcome the substrate sagging phenomenon, a deposition method that uses a substrate standing perpendicular to the ground and deposits on the side (vertical deposition method) has been proposed.

Publication Patent No. 10-2020-0061751 discloses a cluster system that forms a thin film on a vertical substrate. In the case of Patent Publication No. 10-2015-0139222, a uniform thin film deposition process in a vertical evaporation source is disclosed, and methods for deposition direction and driving method are presented.

The present invention seeks to present a gradual evaporation source for vertical evaporation and the configuration of the nozzle and support member included therein, a sensing method to implement a vertical evaporation system, and a loading method to secure the structure and reproducibility of the substrate.

In addition, the present invention aims to propose an in-line vertical evaporation system that prevents sagging of large-area substrates and masks and is capable of depositing a uniform organic thin film. In detail, we aim to solve the problem of material splashing by designing the path of the evaporation material, provide a support that can stably support the position of the evaporation source, provide positioning of the deposition rate sensor according to vertical deposition, and determine the location of the crucible and nozzle. , we would like to present a detailed implementation method for stable vertical deposition, such as providing a structure that can fix the direction.

In addition, it is intended to provide a support member that supports the crucible at a predetermined distance from the heating wire to prevent the heating wire from being damaged by the weight of the crucible.

In accordance with the above object, the present invention provides a point evaporation source equipped with a bending nozzle so that the evaporation material emitted from the point evaporation source has a path that can proceed close to horizontal through the minimum number of deflections.

In addition, the present invention provides an inclined support that can tilt the crucible itself at a predetermined angle, and provides a support member that supports the crucible in the heater unit so that the weight of the tilted crucible does not damage the heating wire.

The inclined support on which the crucible is seated has a sensor seating portion extending from one end to provide a place where the deposition rate sensor can be placed below the bending nozzle.

In the above, a device that helps align the positions of the crucible and the nozzle without distortion is installed on the heater tower insulating part or the top of the cooling device, so that the nozzle direction can be consistent when the crucible is installed.

According to the present invention, the combination of the inclination of the crucible itself and the refraction angle of the bending nozzle allows the evaporated material to travel almost horizontally straight toward the vertical substrate through one to two reflections. This reflection of the evaporated material prevents material splashing, and the bending angle of the nozzle provides a driving force that allows it to travel in a horizontal path against a vertical substrate.

In the present invention, the tilt angle of the crucible itself is not excessive with the help of the bending angle of the bending nozzle, so there is no concern about damage to the hot wire due to the weight of the tilted crucible.

In addition, the deposition rate sensor mounting portion integrated into the crucible support of the present invention can sense the deposition rate without interfering with material deposition on a vertical substrate by fixing the deposition rate sensor below the bending nozzle.

Figure 1 shows a conventional point evaporation source.
Figure 2 is a cross-sectional view showing a point evaporation source equipped with a bent nozzle of the present invention.
Figure 3 is a cross-sectional view showing the path of evaporated material according to the bending nozzle of the present invention.
Figure 4a is an isometric view showing the point evaporation source of the present invention deposited on a support and depositing material on a vertical substrate, and a deposition rate sensor integrated with the support, Figure 4b is a top view, and Figure 4c is a deposition rate sensor shown on the chamber wall. This is a floor plan showing the installation.
FIG. 5A is a side view of an embodiment in which the deposition rate sensor is positioned differently, and FIG. 5B is a top view thereof.
Figures 6 and 7 are diagrams explaining a method of fixing a crucible equipped with a bending nozzle of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows a conventional point evaporation source.

In OLED and semiconductor production using vacuum deposition methods, uniform deposition of accurate thickness plays a major role in determining the quality of displays and devices. Conventionally, when depositing a material on a substrate, a straight nozzle as shown in Figure 1 is used, but in order to apply this straight nozzle to a vertical gradual evaporation source, the angle of the evaporation source must be changed. The present invention implements a vertical deposition system by limiting the evaporation source arrangement angle and replacing the straight nozzle with a bent nozzle.

Accordingly, the present invention provides a point evaporation source equipped with a tubular bending nozzle as shown in FIG. 2. The nozzle installed on the upper part of the crucible 100 constitutes a bending nozzle 200 having a shape equal to the incident angle of θ1 and the refraction angle of θ2 based on a vertical line passing through the center of gravity of the crucible. That is, the bending nozzle 200 has a lower portion having an angle θ1 inclined toward the vertical line and an upper portion having an angle θ2 refracted from the vertical line. θ1 and θ2 can be arranged by tilting the evaporation source itself, including the crucible, and can be determined in combination with the tilt of the evaporation source. This bending nozzle eliminates the phenomenon of material splashing by colliding with the nozzle wall more than once and reflecting when the evaporated material passes through the nozzle. In addition, for a vertically disposed substrate, the crucible tilt and the bending nozzle's refraction angle are designed so that the evaporation material can proceed vertically (horizontally in space) to the substrate surface.

A heater 300 for heating the crucible is arranged around the crucible, and support members 150 and 155 for supporting the crucible are installed on the sides and bottom of the crucible. The outermost part of the evaporation source consists of a cooling unit 400.

Figure 3 is a cross-sectional view showing the path of evaporated material according to the bending nozzle 200 of the present invention.

If the evaporation source itself is tilted, the center of gravity may change and the heating element may be damaged. That is, damage to the heat wire may occur due to the weight of the tilted crucible 100. To prevent this, support members 150 and 155 are installed to support the crucible 100 with respect to the heat wire fixing member to maintain a slight gap. Apply. In a state where the crucible 100 itself is inclined at a predetermined angle θ3 from the plumb line 20, the bending nozzle 200 is configured to have a bending angle equal to the incident angle θ1 and the refraction angle θ2 with respect to the crucible center plumb line 30, so that the evaporation evaporated within the crucible In the bending nozzle 200, water is reflected by the nozzle wall at least once and its path is refracted. The example of FIG. 3 shows a path that is refracted once at the part corresponding to the incident angle θ1 of the bending nozzle 200, and refracted twice again at the refraction angle θ2, and proceeds in an almost horizontal direction. This path of the evaporated material has the effect of preventing material splashing, and the material reaches the vertically arranged substrate surface in an almost perpendicular state, allowing it to be deposited without a shadow effect.

Meanwhile, even in the case of vertical deposition, the deposition rate sensor must be placed in a location that does not interfere with deposition and can properly detect the amount of evaporated material sprayed. Accordingly, the present invention constitutes a deposition rate sensor seating unit integrated with a support for seating the evaporation source in an inclined state.

Figure 4a is an isometric view showing the point evaporation source of the present invention deposited on a support and depositing material on a vertical substrate, and a deposition rate sensor integrated with the support, Figure 4b is a top view, and Figure 4c is a deposition rate sensor shown on the chamber wall. This is a floor plan showing the installation. Figures 4a and 4b show that the sensor is located on the upper side of the nozzle, and Figure 4c shows that the deposition rate sensor is installed on a separate structure, such as the chamber wall 35.

Multiple point evaporation sources can be arranged to form a linear evaporation source.

FIG. 5A is a side view of an embodiment in which the deposition rate sensor is positioned differently, and FIG. 5B is a top view thereof. The deposition rate sensor is placed below the bending nozzle, and the evaporation source module is scanned against the substrate rather than the vertical substrate. Point evaporation sources are arranged along the transverse direction (horizontal direction) of a stationary vertical substrate.

The support 500 on which the evaporation source is mounted has an inclined surface on which the bottom of the evaporation source is seated, and has a deposition rate sensor seating portion 550 extending from the bottom of the support. The deposition rate sensor 600 mounted on the deposition rate sensor mounting portion 550 measures the deposition rate by detecting falling materials sprayed from the bending nozzle. Therefore, the deposition rate can be sensed without interfering with the material path moving from the bending nozzle toward the substrate.

The top view shows the deposition rate sensor positioned extending from the vertical bottom of the bending nozzle. The deposition rate sensor calculates the deposition rate by detecting the material sprayed from the bending nozzle and does not interfere with thin film deposition due to the long distance from the vertical substrate.

Figures 6 and 7 illustrate a method of fixing a crucible equipped with a bending nozzle of the present invention.

A guide member 700 is configured to position the nozzle so that the angle and arrangement of the bending nozzle 200 can be kept constant, and the guide member 700 has a groove 730 that can secure the rear of the nozzle in an interference fit manner. ) is provided. The guide member 700 is configured in a ring shape to seat the upper part of the crucible, and has a protrusion 750 so that the rear part of the nozzle can be inserted into a part of the ring to form a groove 730. In this configuration, the bending nozzle 200 has a protruding rear end in the form of a key that is inserted into the groove 730, and the nozzle and the crucible are mounted at a certain position on the guide member. The guide member may be arranged inside the top of the heater or the top of the cooling section (water jacket). Due to the guide member, the nozzle and crucible can always be aligned in the same position even after repeated attachment and detachment.

In the above, the number of bendings of the bending nozzle 200 may be changed to two or more times. Additionally, the angle of the bent portion may be composed of a curve or curved surface rather than a straight silhouette.

Meanwhile, the vertical substrate to which the point evaporation source with the bending nozzle of the present invention is applied can be modified into an upright substrate arranged with a slight inclination, in addition to a vertical substrate forming a completely vertical angle with respect to the ground. That is, a vertical substrate disposed perpendicular to the ground can be arranged with an inclination as needed, and the inclination may be approximately ±20° from the vertical plane.

The rights of the present invention are not limited to the embodiments described above but are defined by the claims, and those skilled in the art can make various changes and modifications within the scope of the claims. This is self-evident.

Crucible (100)
Support members (150, 155)
Bending nozzle (200)
heater(300)
Cooling unit (400)
Substrate(10)
Plumb line (20)
Chamber wall (35)
Crucible center plumb line (30)
Support (500)
Deposition rate sensor seat (550)
Deposition rate sensor (600)
Guide member (700)
Home(730)

Claims (13)

As an evaporation source,
Crucible;
A tubular bending nozzle disposed on the top of the crucible and bent to have a path where the evaporated material collides with the nozzle wall at least once, is reflected, and is sprayed from the nozzle toward the substrate;
An inclined support that can tilt the evaporation source itself, including the crucible, at a predetermined angle;
A support member supporting the crucible on the side and bottom of the crucible with respect to the heat wire support member so that the weight of the tilted crucible does not damage the heat wire around the crucible;
a sensor mounting portion extending from one end of the inclined support to provide a location where a deposition rate sensor can be placed below the bending nozzle; and
It includes a guide member that positions the bending nozzle so that the angle and arrangement of the bending nozzle can be kept constant,
The guide member is formed in a ring shape that can seat the upper part of the crucible by having a groove that can press-fit the rear of the bending nozzle, and has a protrusion so that the rear portion of the bending nozzle can be inserted into a part of the ring to form a groove. is formed, the bending nozzle has a protruding rear in the form of a key that is inserted into the groove, and the rear of the bending nozzle is fixed to the groove in an interference fit manner, so that the bending nozzle and the crucible are mounted at a certain position on the guide member and bent. The position of the nozzle is always maintained constant even during repeated operations of attachment and detachment of the crucible or bending nozzle,
The bending nozzle includes a lower part having an angle θ1 inclined toward the vertical line based on a vertical line passing through the center of gravity of the crucible, and an upper part having an angle θ2 refracted from the vertical line,
By combining the angle at which the evaporation source is tilted by the inclined support and the bending angle of the bending nozzle of the evaporation source, the evaporation material progresses in a direction perpendicular to the substrate surface and deposits the deposit on the vertically arranged substrate, preventing material splashing. Deposits without shadow effect,
The deposition rate sensor is disposed below the bending nozzle and detects the material sprayed from the bending nozzle below the bending nozzle, measures the deposition rate, and senses the deposition rate without interfering with the material path moving from the bending nozzle toward the substrate. An evaporation source characterized by

delete delete delete delete The evaporation source according to claim 1, wherein the sensor mounting portion and the deposition rate sensor are disposed on a lower side of the bending nozzle. The evaporation source according to claim 1, wherein the sensor mounting portion and the deposition rate sensor are disposed below the front of the bending nozzle. The evaporation source according to claim 1, wherein the evaporation source is a point evaporation source.

delete delete delete Point evaporation source of paragraph 8; and
A substrate on which a material will be deposited by the point evaporation source, comprising a substrate arranged in a direction perpendicular to the ground,
By combining the angle at which the point evaporation source is tilted by the inclined support and the bending angle of the bending nozzle of the point evaporation source, the evaporation material is deposited in a direction perpendicular to the substrate surface, the substrate or the point evaporation source is scanned, and a thin film is deposited on the substrate. A vertical deposition system characterized by forming. Point evaporation source of paragraph 8; and
A substrate on which a material will be deposited by the point evaporation source, comprising a substrate arranged in an upright position inclined at an inclined angle with respect to a vertical plane;
By combining the angle at which the point evaporation source is tilted by the inclined support and the bending angle of the bending nozzle of the point evaporation source, the evaporation material is deposited in a direction perpendicular to the substrate surface, the substrate or the point evaporation source is scanned, and a thin film is deposited on the substrate. A vertical deposition system characterized by forming.