Sputtering device

A sputtering device includes: a sputtering target; a substrate supporter facing the sputtering target and upon which a substrate is disposed; an anode mask between the sputtering target and the substrate which is on the substrate supporter; and a gas distribution member between the anode mask and the sputtering target, and including a plurality of gas distribution tubes separated from each other. Each gas distribution tube includes a plurality of discharge holes defined therein and through which gas is discharged to a vacuum chamber configured to receive the sputtering device.

This application claims priority to Korean Patent Application No. 10-2012-0103290 filed on Sep. 18, 2012, and all the benefits accruing therefrom under 35 U.S.C. §119, the entire contents of which are incorporated herein by reference.

BACKGROUND

The invention relates to a sputtering device.

(b) Description of the Related Art

As a personal computer, a television or the like has been lightened and slimmed, a display device used in the personal computer, the television or the like should be commensurately lightened and slimmed. In order to make the display device lighter and slimmer, a flat panel display such as a liquid crystal display has been developed to replace a cathode ray tube (“CRT”) display of a conventional display device.

The liquid crystal display applies an electric field to a liquid crystal material having dielectric anisotropy which is between two substrates. The liquid crystal display controls the intensity of the electric field to control a quantity of light which is transmitted to one or both of the substrates, thereby acquiring a desired image signal. Since the liquid crystal display may be a portable flat panel display, a thin film transistor liquid crystal display (“TFT LCD”) using a thin film transistor (“TFT”) as a switching element is frequently used as the liquid crystal display.

In manufacturing a liquid crystal display, a sputtering device is one of many manufacturing devices used when a thin film (for example, a metal thin film) is deposited on a substrate for a semiconductor device or on a substrate for a liquid crystal display. The sputtering device is treated as a critical device when the semiconductor device or the liquid crystal display is manufactured.

In the sputtering device, the thin film is generally deposited by the following method. When a voltage is applied in a vacuum state and argon (Ar) gas or oxygen (O2) gas is injected, ions collide with a target while the argon (Ar) gas or the oxygen (O2) gas is ionized. In this case, atoms are discharged from the target and the discharged atoms are attached to the substrate for a semiconductor device or to the substrate for a liquid crystal display, to form the thin film.

A sputtering process may form a thin film at a relatively low temperature as compared to a chemical vapor deposition (“CVD”) process which is performed at a relatively high temperature, and may form a thin film in a relatively short time and in a simple structure such that the thin film is widely used when the semiconductor device or the liquid crystal display is manufactured.

However, as a size of the substrate increases, uniformity of the thin film may undesirably deteriorate. Therefore, there remains a need for an improved sputtering device which provides a uniform thin film on a substrate even as a size of the substrate increases.

SUMMARY

One or more exemplary embodiment of the invention provides a sputtering device having an advantage of improving uniformity of a thin film.

An exemplary embodiment of the invention provides a sputtering device, including a sputtering target; a substrate supporter facing the sputtering target and upon which a substrate is disposed; an anode mask between the sputtering target and the substrate on the substrate supporter; and a gas distribution member between the anode mask and the sputtering target, and including a plurality of gas distribution tubes separated from each other, where each gas distribution tube includes a plurality of discharge holes defined therein and through which gas is discharged to a vacuum chamber configured to receive the sputtering device.

The plurality of discharge holes may be parallel to a plane of the anode mask.

The gas distribution tubes may include a plurality of rods which is separated from and parallel to each other.

The plurality of discharge holes may face the substrate.

The plurality of discharge holes may face the sputtering target.

The plurality of discharge holes may include a first discharge hole facing the sputtering target and a second discharge hole facing the substrate.

The gas discharge member may be connected with a mass inflow meter.

The sputtering device may include a plurality of sputtering targets separated from each other, and the gas distribution tubes may be respectively between adjacent sputtering targets.

The gas discharged through the gas distribution tubes and to the vacuum chamber may be reaction gas which is deposited on the substrate after reacting with a material of the sputtering target.

The reaction gas may include oxygen or nitrogen.

The sputtering device may further include a plurality of magnetrons on the sputtering target and generating a magnetic field.

The gas distribution tube may include a metal material.

The gas is discharged to the vacuum chamber substantially simultaneously.

Another exemplary embodiment of the invention provides a sputtering device, including a plurality of sputtering targets, and a hole defined between adjacent sputtering targets; a substrate supporter facing the plurality of sputtering targets, and upon which a substrate is disposed; an anode mask between the plurality of sputtering targets and the substrate which is on the substrate supporter; and a gas injection tube in communication with a space between a vacuum chamber barrier on a back side of the sputtering targets, and the sputtering targets, and from which gas is discharged. The gas discharged from the gas injection tube is injected into a reaction space between the sputtering targets and the substrate, through the hole defined between the adjacent sputtering targets.

The gas injection tube may be connected with a mass inflow meter which is positioned outside the vacuum chamber barrier.

The sputtering device may further include a plurality of magnetrons on the back side of the plurality of sputtering targets.

According to one or more exemplary embodiment of the invention, a reaction gas is uniformly distributed for plasma generation, by injecting the reaction gas through a gas distribution tube including a plurality of discharge holes corresponding to a horizontal surface (e.g., plane) of an anode mask. Therefore, a thin film formed using the plasma generation is uniform.

DETAILED DESCRIPTION

Hereinafter, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the invention. On the contrary, exemplary embodiments introduced herein are provided to make disclosed contents thorough and complete and sufficient transfer the spirit of the invention to those skilled in the art.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. It will be understood that when a layer is referred to as being “on” another layer or substrate, it can be directly on the other layer or intervening them may also be present. As used herein, connected may refer to elements being physically, electrically and/or fluidly connected to each other. Like reference numerals designate like elements throughout the specification.

Hereinafter, the invention will be described in detail with reference to the accompanying drawings.

FIG. 1is a cross-sectional view illustrating an exemplary embodiment of a sputtering device according to the invention.FIG. 2is a partial lateral cross-sectional view ofFIG. 1.FIG. 3is a plan view illustrating an exemplary embodiment of a portion of the elements of the sputtering device according to the invention.

Referring toFIGS. 1 to 3, an exemplary embodiment of a sputtering device according to the invention includes many elements for depositing a thin film in a vacuum chamber1000. The vacuum chamber1000is configured to receive the sputtering device.

The exemplary embodiment of the sputtering device includes a substrate supporter100upon which a substrate110is disposed, and a sputtering target220which faces the substrate110and includes a target material as a material to be deposited on the substrate110. The substrate supporter100may be configured to move the substrate110in or out of the vacuum chamber1000, and/or to fix the substrate110at a position within the vacuum chamber1000. In addition, the sputtering device includes a power supply1200supplying a power so that the sputtering target220becomes a negative electrode, and a gas supplier (not illustrated) for supplying a discharge gas and reaction gas in the vacuum chamber1000. Here, the substrate110may rotate within the vacuum chamber1000.

Further, an anode mask AM is disposed between the substrate110and the sputtering target220. The anode mask AM functions as a shield member such that a desired portion of the substrate110thereunder may be sputtered while a discharging stability is maintained. The anode mask AM may include an opening defined therein. The opening may extend partially or completely through a thickness of the anode mask AM, and may expose a portion of the substrate110. The opening may correspond to a transmitting region TP of the anode mask AM. The transmission region TP of the anode mask AM may correspond to or be aligned with a region of the substrate110upon which a thin film is to be deposited. The anode mask AM may be electrically independent from the sputtering target220.

Here, the power supply1200may use a direct current (“DC”) or an alternating current (“AC”) power supply.

Additionally, a backing plate210may be disposed at a back side of the sputtering target220. The backing plate210is an assembly upon which the sputtering target220is mounted and is connected with the power supply1200. Cooling water (not shown) for cooling the sputtering target210flows within the backing plate210. A wiring (not shown) for supplying the power from the power supply1200to the backing plate210is connected to the backing plate210.

A plasma region is formed and defined between the sputtering target210and the substrate110, as indicated by the dotted line circle inFIG. 1.

The sputtering target220may be opposite to the substrate110, and may be rectangular or circular shaped. A vacuum pump1100for forming a vacuum state in the vacuum chamber100may be in or connected to the vacuum chamber1000.

In the exemplary embodiment, a gas distribution tube GDT is disposed between the sputtering target220and the substrate110. The gas distribution tube GDT may include a same metallic material as the anode mask AM. As illustrated inFIG. 3, a plurality of rod-shaped anode rods300is arranged separated from each other and substantially parallel to a horizontal surface (e.g., a plane) of the anode mask AM. The anode rods300may have a longitudinal axis which extends in a first direction, while being arranged in a second direction crossing the first direction. The first and second directions may define a plane parallel to the plane of the anode mask, and may be perpendicular to each other, but are not limited thereto or thereby.

An anode rod300includes a plurality of discharge holes310defined therein, and gas flows into the vacuum chamber1000through the discharge holes310. The plurality of discharge holes310is defined along the anode rod300at intervals. The intervals at which the discharge holes310are defined along the anode rod300may be substantially regular and uniform so that the gas flowing therethrough is uniformly distributed in the vacuum chamber1000. The gas distribution tube GDT may collectively include the plurality of anode rods300, and may otherwise be referred to as a gas distribution member.

The gas distribution tube GDT may be connected with a mass flow meter (“MFC”)1300through a nozzle line500connected to each of the anode rods300, and the mass flow meter1300may be connected with a gas supplier (not shown). Further, the gas distribution tube GDT may be connected with the mass flow meter1300through a single guide line550connecting the plurality of nozzle lines500to each other. The mass flow meter1300serves to measure and control a quantity of the gas flowing into the vacuum chamber1000.

When ions collide with the target material in the sputtering target220by plasma generation, atoms and molecules on the surface of the sputtering target220are discharged from the sputtering target220and attach to the substrate110. The target material may include metal, ceramic, polymer or the like. The target material may be a solid state material or a powder state material.

After the vacuum state in the vacuum chamber1000is sufficiently discharged, argon gas and the like may be injected into the vacuum chamber1000so that the discharging of the atoms and molecules is generated.

As described above, the anode rod300has a relatively long and uniform width as the rod shape, but the anode rod300is limited thereto and the shape of the anode rod300may be modified in various shapes.

The plurality of discharge holes310defined in the anode rod300may face the sputtering target220as illustrated inFIGS. 1 and 3. Accordingly, the gas may be emitted toward the sputtering target220from the anode rod300to flow into the vacuum chamber1000. The gas may be discharged through the plurality of discharge holes310substantially simultaneously. An entire of the plurality of discharge holes310may face the sputtering target220, however, is not limited thereto. In an alternative exemplary embodiment, the plurality of discharge holes310defined in the anode rod300may face the substrate110.

As another alternative exemplary embodiment, a first discharge hole may be defined in an anode rod300to face the sputtering target220, and a second discharge hole may be defined in the same anode rod300to face the substrate110at the same time. As still another alternative exemplary embodiment, an entire of the plurality of discharge holes310may be defined in substantially a same horizontal surface (e.g., plane) of an anode rod300, and a plurality of these anode rods300may be disposed such that the discharge holes310face both the substrate110and the sputtering target220.

In sputtering a large-sized substrate, a sputtering device of the related art supplies reaction gas from one end nozzle of a gas injection pipe at one side of a vacuum chamber. Where a thin film is deposited on the large-sized substrate for use in a liquid crystal display by using the sputtering device of the related art, it is difficult to uniformly supply a gas atmosphere in a vacuum chamber where the thin film is deposited. Where the gas is non-uniformly supplied to the vacuum chamber, it is difficult to uniformly deposit the thin film on the substrate because the gas does not form a uniform gas atmosphere in the vacuum chamber. Particularly, in a reactive sputtering process in which an indium tin oxide (“ITO”) thin film is deposited on a transparent electrode glass substrate by using oxygen gas, since the uniformity of the deposited thin film is largely influenced by the uniformity of the gas atmosphere defined by the supplied oxygen gas, a serious problem occurs.

However, in the exemplary embodiment of the invention, since the plurality of discharge holes310is uniformly arranged in the gas distribution tube GDT and the gas distribution tube GDT in the vacuum chamber1000, particularly, between the substrate110and the sputtering target220corresponds to substantially an entire transmitting region TP of the anode mask AM, the reaction gas may be uniformly distributed in the vacuum chamber1000and/or to the substrate110.

In the exemplary embodiment, a magnetron230may be disposed adjacent to and/or around the backing plate210in order to improve a deposition speed, and increase an ionization rate to improve the quality of the deposited thin film. The magnetron230may include one or more magnet or magnetic coil which generates a magnetic field.

FIG. 4is a plan view illustrating another exemplary embodiment of a portion of the elements of a sputtering device according to the invention.

Referring toFIG. 4, in the exemplary embodiment, the sputtering device may include a plurality of discrete sputtering targets220on the backing plate210and separated from each other, in contrast to the single, unitary, indivisible sputtering target of the previous exemplary embodiment described above. Each of the discrete sputtering targets220may individually be a single, unitary, indivisible member, but is not limited thereto or thereby. As illustrated inFIG. 4, a plurality of anode rods300of a collective gas distribution tube GDT may be disposed between adjacent sputtering targets220, respectively.

Any of the arrangements of the anode rods300and/or the plurality of discharge holes310described above may be applied to the exemplary embodiment shown inFIG. 4, but the invention is not limited thereto or thereby.

FIG. 5is a cross-sectional view illustrating another exemplary embodiment of a sputtering device according to the invention.

Referring toFIG. 5, in the exemplary embodiment of a sputtering device, a plurality of discrete sputtering targets220is in the vacuum chamber1000, and the substrate supporter100and the substrate110are disposed at a position opposite to the plurality of sputtering targets220. Further, a plurality of vacuum pumps700may be in fluid, electrical and/or physical communication with the vacuum chamber1000to form a vacuum in the vacuum chamber1000.

A plurality of discrete backing plates210is positioned on the back side of the plurality of sputtering targets220, and a plurality of magnetrons230are arranged at the back side of the plurality of backing plates210. The magnetrons230may be aligned with the sputtering targets220respectively on the backing plates210, but are not limited thereto or thereby. Each of the sputtering targets220is connected to a power supply1200.

A plurality of holes is defined between adjacent sputtering targets220. The holes may be uniformly arranged in the vacuum chamber1000and correspond to substantially an entire of a reaction space between the sputtering targets220and the substrate110.

A single gas injection tube GIT is disposed in a space defined between a barrier CW of the vacuum chamber1000, which is positioned on the back side of the sputtering targets220, and the magnetrons230. The gas injection tube GIT is in communication with the space defined between the barrier CW and the magnetrons230. The gas injection tube GIT is connected to a mass flow meter1300and a gas supplier (not shown). The mass flow meter1300and/or the gas supplier may be outside the vacuum chamber1000, but is not limited thereto or thereby. A reaction gas is injected into the space between the barrier CW of the vacuum chamber1000and the magnetrons230, through the gas injection tube GIT. The injected reaction gas is further injected into the reaction space between the sputtering targets220and the substrate110through the plurality of holes defined between adjacent sputtering targets220among the plurality of sputtering targets220, as illustrated by the “O2” with arrows extended through holes inFIG. 5. The gas may be discharged through the plurality of holes defined between adjacent sputtering targets220substantially simultaneously.

Argon gas and the like for generating plasma may flow into the vacuum chamber1000through a gas inlet1400, in addition to the gas injection tube GIT which may be considered a gas inlet. The argon gas may flow around and into the reaction space between the sputtering targets220and the substrates110, as illustrated by the “Ar” with arrows inFIG. 5.

In the exemplary embodiment of the invention, since the plurality of holes is uniformly arranged in the vacuum chamber1000and corresponds to substantially an entire of a reaction space between the sputtering targets220and the substrate110, the reaction gas may be uniformly distributed in the vacuum chamber1000.