Vapor deposition apparatus

A vapor deposition apparatus including a first region including a first injection unit configured to inject a first raw material, and a second region including a second injection unit configured to inject a second raw material, wherein the second injection unit includes a plasma generation unit, wherein the plasma generation unit includes a plasma generator, a corresponding surface surrounding the plasma generator, and a plasma generation space between the plasma generator and the corresponding surface, and wherein the plasma generator has a groove in a lengthwise direction of the plasma generator.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2012-0125705, filed on Nov. 7, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

Embodiments of the present invention relate to vapor deposition apparatuses.

2. Description of the Related Art

Semiconductor devices, display devices, and other electronic devices include a plurality of thin films. These thin films are formed using various methods, one of which is a vapor deposition method. According to a vapor deposition method, one or more gases are used as a raw material(s) to form thin films. Examples of the vapor deposition method include chemical vapor deposition (CVD), atomic layer deposition (ALD), and the like. In ALD, a raw material is injected (e.g., deposited) onto a substrate, and is then purged and pumped to absorb one or more molecular layers to the substrate, and then another raw material is injected onto the substrate using plasma, and is then purged and pumped to finally form one or more atomic layers.

The plasma is formed by applying a voltage between a first electrode with a pipe shape and a second electrode with a cylinder shape that is located outside the first electrode, and by applying a gas between the first and second electrodes. In the related art, the first electrode is formed of a material such as, for example, steel use stainless (SUS) with high stiffness, to minimize damage caused by plasma.

However, since a material having high stiffness, such as SUS, generally has high resistance, and thus generates much heat, and also has a slow rate of releasing heat, the temperature of an electrode is saturated, and thus it takes long to stabilize a voltage and a current, resulting in a reduction of yield. Moreover, the electrode may be thermally deformed due to a high temperature, and the accompanying ionization of a reaction gas is locally accelerated to generate arc discharge, resulting in a degradation of the uniformity of plasma.

SUMMARY

Embodiments of the present invention provide a vapor deposition apparatus that allows for increased yield, and that generates more uniform plasma.

According to an aspect of embodiments of the present invention, there is provided a vapor deposition apparatus including a first region including a first injection unit configured to inject a first raw material, and a second region including a second injection unit configured to inject a second raw material, wherein the second injection unit includes a plasma generation unit, wherein the plasma generation unit includes a plasma generator, a corresponding surface surrounding the plasma generator, and a plasma generation space between the plasma generator and the corresponding surface, and wherein the plasma generator has a groove in a lengthwise direction of the plasma generator.

The plasma generation unit may have an inflow unit configured to receive the second raw material injected into the plasma generation space, and a discharge unit configured to discharge the second raw material converted to a radical form in the plasma generation space, and the groove may face the inflow unit or the discharge unit.

The groove may include a first groove and a second groove that are parallel to each other, and the plasma generator may include a heat dissipating plate between the first groove and the second groove.

The groove may include a first groove and a second groove that are parallel to each other, and a plurality of heat dissipating fins spaced from each other in a lengthwise direction of the plasma generator may be between the first groove and the second groove.

The plasma generator may include a core unit in a center of the plasma generator, and an outer circumferential unit at least partially surrounding the core unit.

Thermal conductivity and electrical conductivity of the core unit may be respectively higher than thermal conductivity and electrical conductivity of the outer circumferential unit.

The groove may be at least partially defined by the outer circumferential unit and a part of the core unit.

The discharge unit may be configured to pass the second raw material in a radical therethrough, and may have a plurality of slits.

The first region may further include a first purge unit configured to inject a purge gas, a first pumping unit configured to pump between the first injection unit and the first purge unit, and a first curtain unit between the first purge unit and the second injection unit of the second region.

The second region may further include a second purge unit configured to inject a purge gas, a second pumping unit configured to pump between the second injection unit and the second purge unit, and a second curtain unit, and the second purge unit may be between the second pumping unit and the second curtain unit.

According to another aspect of embodiments of the present invention, there is provided a vapor deposition apparatus including a plurality of first regions each including a first injection unit configured to inject a first raw material, a first purge unit configured to inject a purge gas, and a first pumping unit configured to pump between the first injection unit and the first purge unit, and a plurality of second regions each including a second injection unit configured to inject a second raw material, a second purge unit configured to inject a purge gas, and a second pumping unit configured to pump between the second injection unit and the second purge unit, wherein the second injection unit includes a plasma generation unit, wherein the plasma generation unit includes a plasma generator, a corresponding surface surrounding the plasma generator, and a plasma generation space between the plasma generator and the corresponding surface, and wherein the plasma generator has a groove in a lengthwise direction of the plasma generator.

The plasma generation unit may further include an inflow unit configured to pass the second raw material to the plasma generation space, and a discharge unit configured to discharge a second raw material in a radical form generated in the plasma generation space, and the groove may face the inflow unit or the discharge unit.

The groove may include a first groove and a second groove parallel to each other, and the plasma generator may include a heat dissipating plate between the first groove and the second groove.

The groove may include a first groove and a second groove parallel to each other, and the plasma generator may have a plurality of penetration grooves in a lengthwise direction of the plasma generator adjoining the first groove and the second groove.

The plasma generator may include a core unit in a center of the plasma generator, and an outer circumferential unit at least partially surrounding the core unit.

Thermal conductivity and electrical conductivity of the core unit may be respectively higher than thermal conductivity and electrical conductivity of the outer circumferential unit.

The groove may be at least partially defined by the outer circumferential unit and the core unit.

The discharge unit may be configured to pass the second raw material in a radical form therethrough, and has a plurality of slits.

The vapor deposition apparatus may further include a first curtain unit between respective ones of the first purge unit of each of the first regions and the second injection unit of each of the second regions, and a second curtain unit between respective ones of the second purge unit of each of the second regions and the first injection unit of each of the first regions.

The plurality of first regions may alternate with the plurality of second regions.

DETAILED DESCRIPTION

As embodiments of the present invention allow for various changes, particular embodiments will be illustrated in the drawings, and described in detail in the written description. However, this is not intended to limit the present invention to particular modes of practice, and it is to be appreciated that all changes, equivalents, and substitutes that do not depart from the spirit and technical scope of the present invention are encompassed in the present invention. In the following description of embodiments of the present invention, a detailed description of disclosed technology will not be provided if deemed to make features of embodiments of the invention obscure.

While terms such as “first,” “second,” etc., may be used to describe various components, such components must not be limited to the above terms. The above terms are used only to distinguish one component from another.

Hereinafter, embodiments of the present invention will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.

FIG. 1is a schematic cross-section of a vapor deposition apparatus10according to an embodiment of the present invention,FIG. 2is a magnified cross-section of a portion P of the vapor deposition apparatus10ofFIG. 1,FIG. 3is a perspective view of a plasma generator210of the vapor deposition apparatus10ofFIG. 1, andFIG. 4illustrates a plurality of slits251(e.g., of a discharge unit/discharge space) of the vapor deposition apparatus10ofFIG. 1, according to an embodiment of the present invention.

Referring toFIG. 1, the vapor deposition apparatus10according to the current embodiment includes a first region110and a second region120. A plurality of the first regions110and a plurality of the second regions120may be arranged, and the first regions110may alternate with the second regions120.

A substrate1is positioned below the vapor deposition apparatus10and moves relative to the vapor deposition apparatus10to sequentially pass by/under the first regions110and the second regions120. For example, the substrate1may move in a direction X, and a desired thin film may be formed on the substrate1using the vapor deposition apparatus10.

Each of the first regions110may include a first injection unit111, a first pumping unit112, a first purge unit113, and a first curtain unit114.

The first injection unit111injects a first raw material for deposition. In detail, the first injection unit111injects a first raw material in a gas state in a direction toward the substrate1.

The first purge unit113injects (e.g., ejects) a purge gas in the direction toward the substrate1. The first purge unit113injects a gas that does not affect deposition, for example, an argon gas or a nitrogen gas, in the direction toward the substrate1.

The first pumping unit112is located between the first injection unit111and the first purge unit113, and pumps (e.g., by creating suction) a physical absorption layer separated from the substrate1by the purge gas, in a direction indicated by an arrow ofFIG. 1.

The first curtain unit114is formed adjacent a second region120, and injects a curtain gas, which may be an inert gas that does not affect a deposition process. The first curtain unit114is formed adjacent the second region120to block a material generated in, or injected by, the first region110from entering into the second region120during a deposition process, and to block a material generated in, or injected by, the second region120from entering into the first region110.

A first barrier A131is formed to separate the first pumping unit112and the first injection unit111adjacent each other, and to separate the first pumping unit112and the first purge unit113adjacent each other. In other words, the first pumping unit112and the first injection unit111do not share any region, and the first pumping unit112and the first purge unit113do not share any region.

A second barrier A141may be formed between the first injection unit111and another gas injection unit adjacent to the first injection unit111, for example, a second curtain unit124located to the left of the first region110, to separate the first injection unit111and the second curtain unit124. A third barrier A151may be formed between the first purge unit113and the first curtain unit114adjacent each other to separate the first purge unit113and the first curtain unit114.

Each of the second regions120may include a second injection unit121, a second pumping unit122, a second purge unit123, and a second curtain unit124.

The second injection unit121injects a second raw material for deposition, and includes a plasma generation unit200for generating plasma.

Referring toFIG. 2, which is a magnified view of the plasma generation unit200, which includes a plasma generator210, a corresponding surface220, and a plasma generation space230formed between the plasma generator210and the corresponding surface220. The plasma generation unit200may further include an inflow unit240for injecting a second raw material into the plasma generation space230, and a discharge unit250for discharging the second raw material in a radical form generated in the plasma generation space230.

The plasma generator210may be an electrode to which a voltage is applied. The corresponding surface220may formed to surround the plasma generator210, and may be a grounded electrode. However, the present invention is not limited thereto, for example, the plasma generator210may be grounded, and a voltage may be applied to the corresponding surface220.

A groove212is formed on one side of the plasma generator210. In more detail, as illustrated inFIG. 3, the groove212may be formed in the lengthwise direction of the plasma generator210.

When the groove212is formed on the plasma generator210, the surface area of the plasma generator210increases, and thus heat emission (e.g., dissipation) efficiency may improve. Consequently, even when the plasma generator210continuously generates heat when generating plasma, a saturation temperature of the plasma generator210decreases due to efficient heat emission.

In general, since metal has the property that resistance increases with an increase in temperature, if the saturation temperature that the plasma generator210reaches decreases, a resistance change of the plasma generator210due to an increase in temperature may be reduced or minimized, and thus the time required to stabilize the voltage characteristics of the plasma generator210may be decreased, allowing for an improvement in the yield of the vapor deposition apparatus10.

In more detail, the resistance of the plasma generator210varies due to heat emission, and accordingly the voltage of the plasma generator210changes. Consequently, when a deposition process is conducted before the temperature of the plasma generator210is the saturation temperature namely, before the voltage of the plasma generator210is stabilized, the characteristics of a thin film formed in the early part of the deposition process may be different from those of a thin film formed while the temperature of the plasma generator210is increasing or different. Accordingly, the deposition process needs to be conducted after the stabilization of the voltage characteristics of the plasma generator210to make the characteristics of thin films more uniform. According to embodiments of the present invention, the time required for the stabilization is reduced, and thus the yield of the vapor deposition apparatus10may improve.

Moreover, if the saturation temperature of the plasma generator210decreases, thermal deformation of the plasma generator210is reduced or prevented, and thus arc discharge may be reduced or prevented from occurring due to relatively fast local progress of ionization of a reaction gas. A voltage and a current applied to the plasma generator210may be stabilized, thereby forming more uniform plasma.

For example, plasma may be formed by applying a pulse voltage to the plasma generator210to generate a potential difference between the plasma generator210and the corresponding surface220, which surrounds the plasma generator210, and introducing a reaction gas into the plasma generation space230. Thus, since a portion of the plasma generation unit200where the discharge unit250is formed is not used in plasma discharge, the groove212may be formed opposite to the discharge unit250so as to not affect plasma discharge.

In the plasma generation space230, the second raw material passes through the plasma and acquires a radical form. The second raw material in a radical form is transmitted in the direction toward the substrate1via the discharge unit250. For example, the discharge unit250may be formed so that the second raw material in a radical form passes therethrough, and may have the slits251, which are arranged in one direction.

Referring toFIG. 4, which illustrates the slits251of the vapor deposition apparatus10, the slits251may be arranged at regular intervals in the lengthwise direction of the plasma generator210. The second raw material in a radical form, which is generated in the plasma generation space230, may be uniformly supplied onto the substrate1via the slits251, and may be supplied without locally concentrating on the second injection unit121. Although the slits251are circles having the same sizes in the embodiment shown inFIG. 4, the present invention is not limited thereto, and the slits251may have various other sizes and shapes.

Referring back toFIG. 1, the second purge unit123injects a purge gas in the direction toward the substrate1. The gas may be a gas that does not affect deposition, for example, an argon gas or a nitrogen gas, in the direction toward the substrate1.

The second pumping unit122is located between the second injection unit121and the second purge unit123. After the second raw material is injected from the second injection unit121toward the substrate1, the purge gas may be injected by the second purge unit123toward the substrate1, and the purge gas may be pumped by the second pumping unit122to form a first layer containing the first raw material and the second raw material on the substrate1.

The second curtain unit124is formed adjacent another first region110that is next to the second curtain unit124in a direction in which the substrate1moves. The second curtain unit124injects a curtain gas, and the curtain gas may be an inert gas that does not affect a deposition process.

According to the present embodiment, the substrate1and the vapor deposition apparatus10conduct a deposition process while moving relative to each other, and the second curtain unit124blocks a material generated in, or injected by, the second region120from mixing with a material generated in, or injected by, a first region110(located on the right side of the second region120inFIG. 1) during the deposition process.

A first barrier B132is formed to separate the second pumping unit122and the second injection unit121adjacent each other, and to separate the second pumping unit122and the second purge unit123adjacent each other. In other words, the second pumping unit122and the second injection unit121do not share any region, and the second pumping unit122and the second purge unit123do not share any region.

Similarly, a second barrier B142may be formed between the second injection unit121and another gas injection unit adjacent to the second injection unit121, and a third barrier B152may be formed between the second purge unit123and the second curtain unit124.

A deposition process performed by the above-described vapor deposition apparatus10will now be described briefly.

The substrate1moves in the direction X ofFIG. 1while under the vapor deposition apparatus10. To this end, the substrate1may be mounted on a stage, and may be moved by a driving unit. Alternatively, the substrate1may move in the direction X, and/or the vapor deposition apparatus10may move in an opposite direction (−X.)

In the first region110, a first raw material is injected by the first injection unit111in the direction toward the substrate1. For example, the first raw material may be a gas containing aluminum (Al) atoms, such as trimethyl aluminum (TMA), but the present invention is not limited thereto.

A chemical absorption layer and a physical absorption layer are formed on an upper surface of the substrate1by the first raw material. The physical absorption layer, which has weak intermolecular coherence, is separated from the substrate1by the purge gas injected by the first purge unit113, and is effectively removed from the substrate1via pumping of the first pumping unit112. Therefore, a deposition film to be formed on the substrate1may have improved purity.

Since the first barriers A131are formed between the first pumping unit112and the first purge unit113, and between the first pumping unit112and the first injection unit111, the pumping of the first pumping unit112may be prevented from affecting the first injection unit111and the first purge unit113.

The substrate1is moved from the first region110to the second region120, and a second raw material is injected onto the substrate1by the second injection unit121of the second region120. Since the first region110and the second region120are effectively separated from each other by the first curtain unit114of the first region110, mixing of undesired materials in each operation of the deposition process is reduced or prevented.

The second injection unit121injects the second raw material in a radical form generated in the plasma generation space230.

As described above, due to the formation of the groove212on the plasma generator210, heat of the plasma generator210may be more efficiently discharged outside. Accordingly, by decreasing the saturation temperature that the plasma generator210reaches the time required to stabilize the voltage of the plasma generator210is reduced, and thus the yield of the vapor deposition apparatus10may increase. Moreover, more uniform plasma may be formed by reducing or preventing thermal deformation of the plasma generator210, and a more uniform thin film having little to no variations in characteristics, even when the deposition process continues, may be formed.

The second raw material may include, for example, an oxygen radical, which may be formed by injecting H2O, O2, N2O, or the like into the plasma generation space230. The second raw material reacts with the chemical absorption layer formed of the first raw material having already absorbed to (e.g., been absorbed by) the substrate1, or replaces a part of the chemical absorption layer, and a deposition layer such as, for example, an AlxOy layer, is formed. At this time, an excess of the second raw material forms a physical absorption layer, and the physical absorption layer remains.

The second purge unit123injects a purge gas onto the substrate1to separate the remaining physical absorption layer from the upper surface of the substrate1. The separated physical absorption layer is effectively removed from the substrate1via pumping of the second pumping unit122, thereby forming a deposition layer with improved purity on the substrate1. At this time, the pumping of the second pumping unit122does not affect the directionalities of the second raw material injected by the second injection unit121, or of the purge gas injected by the second purge unit123, due to the formation of the first barrier B132. As such, while passing through the first region110and the second region120, a desired single atomic layer is formed on the substrate1.

FIGS. 5 and 6illustrate modified examples of the plasma generation unit200of the vapor deposition apparatus10ofFIG. 1.

Since a plasma generation unit200B ofFIG. 5and a plasma generation unit200C ofFIG. 6are the modified examples of the plasma generation unit200ofFIG. 2, only differences between the plasma generation unit200and each of the plasma generation units200B and200C will now be described.

First, the plasma generation unit200B ofFIG. 5is different from the plasma generation unit200ofFIG. 2in that the groove212formed on the plasma generator210faces the inflow unit240.

As described above, since plasma is generated between the plasma generator210and the corresponding surface220, unlike the discharge unit250, the inflow unit240is not used in plasma discharge. Accordingly, when the groove212is formed to face the inflow unit240, the formation of the groove212does not affect plasma discharge. Since the inflow unit240has a relatively low temperature, when the groove212is formed to face the inflow unit240, heat emission efficiency of the plasma generator210may improve.

Like the plasma generation unit200ofFIG. 2, the plasma generation unit200C ofFIG. 6includes a plasma generator210B, a corresponding surface220, and a plasma generation space230formed between the plasma generator210B and the corresponding surface220.

However, the plasma generation unit200C ofFIG. 6is different from the plasma generation unit200ofFIG. 2in that the plasma generator210B includes a first groove212A and a second groove212B, instead of the single groove212of the plasma generator210ofFIG. 2.

Referring toFIG. 6, the first groove212A and the second groove212B are formed apart from each other, and extend in the lengthwise direction of the plasma generator210B, and thus the plasma generator210B includes a heat-dissipating plate213formed between (e.g., partially defining) the first groove212A and the second groove212B. Therefore, the surface area of the plasma generator210B increases, leading to an improvement of heat emission efficiency.

Although the first groove212A and the second groove212B face the discharge unit250inFIG. 6, the present invention is not limited thereto, and the first groove212A and the second groove212B may face the inflow unit240, like the plasma generation unit200B ofFIG. 5.

Although two grooves, namely, the first and second grooves212A and212B, and the single heat-dissipating plate213formed between the first and second grooves212A and212B are illustrated inFIG. 6, the present invention is not limited thereto. For example, the plasma generator210B may include three or more grooves, and accordingly, two or more heat-dissipating plates may be included.

FIG. 7is a perspective view of a plasma generator210C of the vapor deposition apparatus10ofFIG. 1, taken along the line A-A′ ofFIG. 6, according to another embodiment of the present invention.

Although a shape obtained by cutting the plasma generator210B ofFIG. 6along the line A-A′ ofFIG. 6is illustrated inFIG. 7for convenience of explanation, the plasma generator210C is different from the plasma generator210B ofFIG. 6.

The plasma generator210C ofFIG. 7is different from the plasma generator210ofFIG. 2in that it includes the first groove212A and the second groove212B (instead of the single groove212of the plasma generator210ofFIG. 2). In other words, since the plasma generator210C ofFIG. 7is a modified example of the plasma generator210ofFIG. 2, only differences therebetween will now be described.

Referring toFIG. 7, the first groove212A and the second groove212B are formed apart from each other, and extend in the lengthwise direction of the plasma generator210C. The plasma generator210C further includes a plurality of penetration grooves215that are arranged apart from each other in the lengthwise direction of the plasma generator210C, and that adjoin the first groove212A and the second groove212B. Accordingly, a plurality of heat-dissipating fins214separate from each other in the lengthwise direction of the plasma generator210C are formed between (e.g., partially define) the first groove212A and the second groove212B.

The heat-dissipating fins214effectively increase the surface area of the plasma generator210C, thereby improving heat emission efficiency of the plasma generator210C. The heat-dissipating fins214may be formed to face an inflow unit or a discharge unit of a plasma generation unit.

FIG. 8is a cross-section of another modified example of the plasma generation unit200of the vapor deposition apparatus10ofFIG. 1.

Since a plasma generation unit200D ofFIG. 8is the modified example of the plasma generation unit200ofFIG. 2, only differences therebetween will now be described.

Referring toFIG. 8, a plasma generator210D includes a core unit217formed in the center, and an outer circumferential unit218formed on the outer surface of the core unit217.

The core unit (e.g., inner core)217and the outer circumferential unit (e.g., outer core)218may be formed of different materials. However, the different materials used to form the core unit217and the outer circumferential unit218may allow thermal conductivity and electrical conductivity of the core unit217to be higher than those of the outer circumferential unit218. For example, the core unit217may be formed of aluminum, copper, silver, or an alloy of these materials, and the outer circumferential unit218may be formed of a material having high strength and high durability, such as stainless steel or SUS, to protect the core unit217from plasma. However, the present invention is not limited thereto.

As such, when the plasma generator210D includes the core unit217having high thermal conductivity and high electrical conductivity in its center, a rate of resistance increase of the plasma generator210D may decrease even when the temperature of the plasma generator210D increases.

The plasma generator210D includes the groove212formed in the lengthwise direction of the plasma generator210D. The groove212extends from the outer circumferential unit218to a part of the core unit217so as to expose the core unit217. Accordingly, as the core unit217, having high thermal conductivity, is exposed, the heat of the plasma generator210D may be effectively discharged.

Since the groove212may be formed to face the discharge unit250, plasma discharge is not interrupted by the groove212, and a part of the core unit217exposed via the groove212may be prevented from being damaged by the plasma.

The groove212may be formed to face the inflow unit240, as illustrated inFIG. 5, and/or two or more grooves may be formed, as illustrated inFIG. 6.

According to an embodiment of the present invention, heat emission efficiency of a plasma generator may improve to allow for an increase the yield of a vapor deposition apparatus, and more uniform plasma may be generated.

Since the components illustrated in the drawings are enlarged or downsized for convenience of explanation, the present invention is not restricted by the sizes or shapes of the components illustrated in the drawings. While embodiments of the present invention have been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims, and their equivalents.