JP2011017034A - Sputtering system and device for producing liquid crystal device - Google Patents

Abstract

In a reactive sputtering apparatus in which sputtering particles are supplied from an oblique direction of a substrate, a sputtering apparatus capable of ensuring a good film formation rate is provided.
A film forming chamber 2 having a substrate holder 6 for holding a substrate W and capable of transporting the substrate holder 6 and a sputtering chamber 3 communicating with the film forming chamber 2 and having a target 10 disposed therein are provided. A sputtering apparatus for forming a reaction product film on a substrate W by a reaction between sputtering particles discharged from the sputtering chamber 3 to the film formation chamber 2 and a reaction gas. A box 20 having a hole larger than the outer periphery of the target 10 is provided in the sputtering chamber 3, and the surface of the target 10 faces the inner surface of the box 20 through the first opening 21 of the box 20, A second opening 22 through which the sputtered particles pass is provided in a part of the surface of the box 20 facing the target 10.
[Selection] Figure 1

Description

  The present invention relates to a sputtering apparatus and a liquid crystal device manufacturing apparatus.

Conventionally, inorganic alignment films have been studied in order to improve the reliability of alignment films used in liquid crystal devices and the like.
In the production of this inorganic alignment film (inorganic alignment film), for example, as shown in Patent Document 1, it has a film formation chamber in which a substrate is accommodated, and a sputtered particle emitting portion (sputtering chamber) in which a target is disposed oppositely. The opposed target type sputtering apparatus is used.
The facing target type sputtering apparatus generates a plasma in a facing space by arranging a pair of targets facing each other with a predetermined interval in a vacuum chamber, and forms a thin film on a substrate disposed on the side of the facing space. Device.

In recent years, it has been required to increase the alignment angle of the alignment film, and it is necessary to form a film with a small incident angle. In this case, the facing target sputtering apparatus has a problem that the film formation rate is greatly reduced.
In the facing target type sputtering apparatus, sputtering particles emitted obliquely from the surface of the facing target are used, and the film forming rate is lowered in the film forming at a shallow incident angle where the distance between the target and the substrate becomes large. Inevitable.
On the other hand, in the magnetron sputtering type apparatus, there are many rectilinear components of the sputtered particles, and even when the distance between the target and the substrate is increased, the film forming rate is not reduced as much as the facing target type sputtering apparatus. Is possible.

JP 2007-286401 A

  However, when reactive sputtering is performed using a magnetron sputtering apparatus, the reaction gas and the sputtering particles react in the sputtering chamber, and the reaction product is deposited on the target surface, resulting in a decrease in film formation rate. There's a problem.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  [Application Example 1] A sputtering apparatus according to this application example has a substrate holder for holding a substrate, the substrate holder is provided so as to be transportable, and communicates with the film formation chamber into which a reaction gas is introduced. A sputtering chamber in which a target is disposed, and a sputtering apparatus for forming a reaction product film on the substrate by a reaction between the sputtering particles discharged from the sputtering chamber to the film formation chamber and the reaction gas, The target is disposed obliquely with respect to the transport path of the substrate holder, and a box having a first opening larger than the outer periphery of the target is provided in the sputtering chamber on one surface formed parallel to the surface of the target. The surface of the target faces the inner surface of the box through the first opening of the box and before the target faces And wherein the second opening portion in which the sputtered particles on a part of the surface of the box body passes is provided.

According to this configuration, the sputtering gas can be confined in the box of the sputtering chamber, and the reaction gas from the film forming chamber can be reduced from flowing into the box.
Therefore, in addition to the stable discharge state in the sputtering chamber, the reaction gas does not flow into the target surface and the reaction product is not deposited on the target surface, so that a stable film formation rate can be obtained.
Further, by using the second opening provided in the box, it is possible to select the sputtered particles and discharge the sputtered particles having high directivity to the film forming chamber.
Furthermore, sputtering particles that do not contribute to film formation are trapped inside the box, and the box functions as a deposition preventing plate, thereby preventing particles resulting from sputtering from reaching the substrate.

  Application Example 2 In the sputtering apparatus according to the application example described above, it is preferable that the sputtering gas is directly supplied into the box of the sputtering chamber.

  According to this configuration, the sputtering gas can be filled inside the box, and a stable discharge state can be maintained. For this reason, the film-forming rate of sputtering is stabilized and the uniformity of a film thickness is securable.

  Application Example 3 In the sputtering apparatus according to the application example described above, it is preferable that the sputtering gas is supplied into the box from near the surface above the target.

  According to this configuration, since the sputtering gas is supplied from near the upper surface of the target, the sputtering gas can flow from the upper surface to the lower surface of the inclined target. From this, particles generated on the surface of the target can be swept downward, and deterioration of the film quality due to the particles on the target can be prevented.

  Application Example 4 In the sputtering apparatus according to the application example described above, a control plate for selectively passing a part of the sputtering particles is provided between the substrate holder and the sputtering chamber of the film forming chamber. Is desirable.

  According to this configuration, the sputtered particles emitted from the second opening of the box can be further selected and passed by the control plate, and the sputtered particles having high directivity can reach the substrate. This makes it possible to form a film with good film quality.

  Application Example 5 An apparatus for manufacturing a liquid crystal device according to this application example includes a liquid crystal layer sandwiched between a pair of opposing substrates, and a liquid crystal formed by forming an inorganic alignment film on the inner surface side of at least one of the substrates. An apparatus for manufacturing an apparatus, comprising the sputtering apparatus according to any one of Application Examples 1 to 4, wherein the inorganic alignment film is formed by the sputtering apparatus.

  According to the liquid crystal device manufacturing apparatus of this application example, since the sputtering device capable of forming an inorganic alignment film having a large alignment angle is provided, a liquid crystal device including an inorganic alignment film with good characteristics can be manufactured.

The schematic block diagram which shows an example of the sputtering device of embodiment. The perspective view which shows the box concerning the sputtering device of embodiment. The top view of the TFT array substrate which comprises a liquid crystal device. FIG. 6 is a schematic cross-sectional view of a liquid crystal device illustrating a liquid crystal device.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. In the drawings used for the following description, the ratio of dimensions of each member is appropriately changed so that each member has a recognizable size.
(Embodiment)

FIG. 1 is a schematic configuration diagram showing an example of the sputtering apparatus of the present embodiment. FIG. 2 is a perspective view showing a box according to the sputtering apparatus. The sputtering apparatus constitutes an apparatus for manufacturing a liquid crystal device, and forms an inorganic alignment film on a substrate that is a constituent member of the liquid crystal device.
In the following description of the sputtering apparatus, for convenience, the description will be made using an orthogonal coordinate system.
As shown in FIG. 1, the sputtering apparatus 1 includes a film formation chamber 2 that accommodates a substrate W, and a sputtering chamber 3 that generates plasma and discharges sputtering particles from a target. The sputtered particles are constituent atoms of the target that pop out due to the sputtering phenomenon.

The film forming chamber 2 is connected to an exhaust control device 30 configured by a rotary pump, a cryopump, and the like for controlling the chamber pressure and obtaining a desired degree of vacuum.
A reactive gas supply means 14 is provided for supplying oxygen gas as a reactive gas that reacts with the sputtered particles flying on the substrate W accommodated in the film forming chamber 2 to form an inorganic alignment film.
The reactive gas supply means 14 is connected to the opposite side of the exhaust control device 30, and the oxygen gas supplied from the reactive gas supply means 14 flows from the −X side to the + X side of the film forming chamber 2 and will be described later. It flows through the upper part of the sputtering chamber 3 to the exhaust control device 30 side.

  The film formation chamber 2 has a substrate holder 6 that holds the surface to be processed (film formation surface) of the substrate W so that it is parallel (horizontal) to the XY plane. The substrate holder 6 is connected to moving means 7 for conveying the substrate holder 6. The transfer of the substrate W by the moving means 7 can be performed at a constant speed parallel to the X-axis direction in FIG. 1, and a high-quality inorganic alignment film is formed on the substrate W by the sputtering particles emitted from the sputtering chamber 3. It can be done.

The substrate holder 6 is provided with a heater (not shown) as a heating means for heating the held substrate W, and further provided with a cooling means 8 for cooling the held substrate W. The heater is configured to heat the substrate holder 6 to a desired temperature. On the other hand, the cooling means 8 is connected to the refrigerant circulation means 9 and is configured to cool the substrate holder 6 to a desired temperature by circulating the refrigerant supplied from the refrigerant circulation means 9.
Further, a control plate 25 is disposed in the film forming chamber 2 between the moving path of the substrate holder 6 and the sputtering chamber, and an opening 26 is provided for selectively passing the emitted sputtering particles. Yes.

  A substrate supply chamber 4 is disposed on the −X side of the film formation chamber 2, and a substrate recovery chamber 5 is disposed on the + X side of the film formation chamber 2. The substrate supply chamber 4 and the substrate recovery chamber 5 are connected to an exhaust control device that independently adjusts the decompressed atmosphere. The film formation chamber 2, the substrate supply chamber 4, and the substrate recovery chamber 5 are connected via gate valves 28 and 29 that hermetically close the chambers.

The substrate W waiting in the reduced pressure atmosphere in the substrate supply chamber 4 is transferred to the film forming chamber 2 by opening the gate valve 28. When the substrate W leaves the substrate supply chamber 4, the gate valve 28 is closed. . When film formation is completed in the film formation chamber 2, the gate valve 29 is opened, the substrate W is transferred to the substrate recovery chamber 5 maintained in a reduced pressure atmosphere, and when the substrate W leaves the film formation chamber 2, the gate valve is opened. 29 is closed.
In this way, the substrate W can be taken in and out without opening the film formation chamber 2 to the atmosphere by opening and closing the gate valves 28 and 29.

The sputtering chamber 3 has a configuration in which a rectangular parallelepiped is cut obliquely, and the film forming chamber 2 and the sputtering chamber 3 are attached so that the cut ends are opened.
The film formation chamber 2 has side plates 18a and 18b that constitute outer walls, and is configured to be removable. An O-ring 19 is provided between the side plates 18a and 18b and the outer wall 2a and the flange portion 17 of the film forming chamber 2 in order to keep the inside of the film forming chamber 2 airtight, and the side plates 18a and 18b are fastened by mounting screws. Yes.

  A target 10 is provided on one surface of the sputtering chamber 3. In the sputtering chamber 3, the surface direction (Za direction) of the target 10 held in the sputtering chamber 3 is predetermined with respect to the film surface normal direction (Z direction) of the substrate W accommodated in the film forming chamber 2. The angle θ is formed. In other words, the angle formed by the surface direction (Za direction) of the target 10 held in the sputtering chamber 3 and the transport direction (X direction) of the substrate holder 6 forms a predetermined angle.

More specifically, the target 10 is held at a predetermined angle θ that is inclined by 10 ° to 60 ° with respect to the normal direction of the substrate W.
In the present embodiment, the substrate holder 6 is transported in the transport direction from the start point -X to the end point in the + X direction during film formation, and the surface of the target 10 is disposed toward the end point side of transport of the substrate holder 6.
Further, it is preferable that the target 10 and the substrate holder 6 are disposed at a distance of at least 20 cm during film formation. In this way, most of the sputtered particles can reach the substrate W at a predetermined incident angle without colliding in the middle.
The target 10 is made of a material containing a constituent material of the inorganic alignment film formed on the substrate W, for example, silicon. The target 10 is a long and thin plate extending in the Y direction.

One surface of the target 10 is mounted on a flat plate-like backing plate 11, and the backing plate 11 is attached to a side plate 18 a that forms the outer wall of the film forming chamber 2. An insulating plate 16 is disposed between the side plate 18a and the backing plate 11.
An inner magnet 12a, an outer magnet 12b, and a yoke 13 are provided on the back surface of the backing plate 11. The inner magnet 12 a and the outer magnet 12 b are arranged in opposite polarities, and the end portions of both magnets are connected to the yoke 13. Due to this magnetic circuit, magnetic field lines having a component parallel to the surface of the target 10 are generated near the surface of the target 10.

Further, the backing plate 11 serves as an electrode, to which a power source comprising a DC power source or a high frequency power source is connected.
Further, although not shown, a cooling means for cooling the target 10 is connected to the backing plate 11.
Thus, the sputtering apparatus 1 of the present embodiment constitutes a magnetron sputtering apparatus.

A box 20 is disposed in the space of the sputtering chamber 3. The box 20 has a shape along the inner wall of the sputtering chamber 3, and a space is formed therein.
As shown in FIGS. 1 and 2, the box 20 has a first opening 21 that is larger than the outer periphery of the target 10 on one surface arranged substantially parallel to the surface of the target 10. The surface of the target 10 faces the inner surface of the box 20 through the first opening 21. And the 2nd opening part 22 through which sputtering particle passes is provided in a part of surface of the box 20 in which the surface of the target 10 faces.

The box 20 is attached and fixed to the side plate 18b by the attachment portion 23. In order to prevent the reaction gas introduced into the film forming chamber 2 from entering the gap between the box 20 and the inner wall of the sputtering chamber 3, it is effective to narrow the gap as much as possible.
The second opening 22 of the box 20 regulates the sputtering particles passing therethrough by selecting the opening position and width, and discharges the sputtering particles with high directivity to the film forming chamber 2.
Further, the sputtering chamber 3 is provided with a sputtering gas supply means 15 for flowing a discharge argon gas. The argon gas is supplied with a hole in a part of the box 20 so as to directly flow into the box 20 of the sputtering chamber 3 and near the surface above the target 10. In this way, the argon gas can flow down the particles generated on the surface of the target 10, and the film quality deterioration caused by the particles on the target 10 can be prevented. Further, the argon gas filled in the box 20 is configured to flow into the film forming chamber 2.
Then, with the sputtering gas supplied, plasma is generated above the target 10 by the power supplied from each power source.

Since the volume of the box 20 in the sputtering chamber 3 is much smaller than the volume in the film forming chamber 2 and the exhaust control device 30 connected to the film forming chamber 2 exhausts the air, Is higher than the pressure in the film forming chamber 2 due to the introduced sputtering gas, and a pressure gradient is generated from the sputtering chamber 3 toward the film forming chamber 2. Therefore, while the sputtering gas flows out from the sputtering chamber 3 toward the film forming chamber 2, it is difficult for the reaction gas introduced directly into the large volume film forming chamber 2 to flow into the sputtering chamber 3 from the film forming chamber 2. .
Further, the reaction gas that is about to flow in from the second opening 22 of the box 20 reacts with the released sputtering particles quickly and is trapped, and cannot enter the inside of the box 20.

  In order to form an inorganic alignment film on the substrate W using the sputtering apparatus 1 having the above-described configuration, first, a DC or AC high voltage is applied to the backing plate 11 while introducing argon gas from the sputtering gas supply means 15. As a result, plasma is generated above the target 10. By causing argon ions in the plasma atmosphere to collide with the target 10, the alignment film material (silicon) is sputtered from the target 10 as sputtering particles. Furthermore, only the sputtered particles that pass through the second opening 22 of the box 20 among the sputtered particles knocked out of the target 10 are released to the film forming chamber 2 side.

Sputtered particles emitted from the second opening 22 of the box 20 have the same incident angle and become highly directional sputtering particles. These sputtered particles can reach the substrate W through the control plate 25 so that sputtered particles with higher directivity can reach the substrate W from the opening 26.
Then, an alignment film made of silicon oxide is formed on the substrate W by causing the sputtered particles flying from the oblique direction on the surface of the substrate W to react with the oxygen gas flowing through the film forming chamber 2 on the substrate W. To do.
As described above, according to the sputtering apparatus 1, sputtering particles with high directivity are supplied to the substrate W, and an inorganic alignment film having a columnar structure aligned in one direction by reacting with the reaction gas is formed on the substrate W. Can do.
In addition, the sputtering apparatus 1 is good also as a structure which does not provide the control board 25 which further raises the directivity of sputtering particle.

As described above, in the sputtering apparatus 1 of the present embodiment, the sputtering gas can be confined in the box 20 of the sputtering chamber 3, and the reaction gas from the film forming chamber 2 can be reduced from flowing into the box 20. it can. From this, in addition to the stable discharge state in the sputtering chamber, the reaction gas does not flow into the surface of the target 10 and the reaction product does not accumulate on the surface of the target 10, and a stable film formation rate can be obtained. .
Furthermore, sputtering particles that do not contribute to film formation are captured inside the box 20, and the box functions as a deposition preventing plate, and particles resulting from sputtering can be prevented from reaching the substrate W.

In the present embodiment, the case where silicon as a sputtered particle is reacted with oxygen gas to form a silicon oxide film on the substrate W is described. However, another target material and a reactive gas are used. It is also possible to form oxide, nitride, etc. on the substrate W.
(Liquid crystal device)

Hereinafter, an example of a liquid crystal device that can be manufactured using the sputtering apparatus 1 described above will be described with reference to the drawings.
The liquid crystal device according to the present embodiment is a TFT active matrix type transmissive liquid crystal device having a configuration in which a liquid crystal layer is sandwiched between a TFT array substrate arranged opposite to each other and a counter substrate.
FIG. 3 is a plan view of a TFT array substrate constituting the liquid crystal device of the present embodiment. FIG. 4 is a schematic cross-sectional view of the liquid crystal device.

As shown in FIG. 3, the TFT array substrate 110 has an image display area 101 formed at the center. A sealing material 102 is disposed on the peripheral edge of the image display area 101, and the TFT array substrate 110 and the counter substrate 120 are bonded together by the sealing material 102, and the area surrounded by both the substrates 110, 120 and the sealing material 102. A liquid crystal layer (not shown) is sealed.
A scanning line driving circuit 103 that supplies a scanning signal to the scanning lines and a data line driving circuit 104 that supplies an image signal to the data lines are mounted outside the sealing material 102. A plurality of connection terminals 106 connected to an external circuit are provided at the end of the TFT array substrate 110, and wirings extending from the drive circuits 103 and 104 are connected to the connection terminals 106. In addition, inter-substrate conduction portions 105 that electrically connect the TFT array substrate 110 and the counter substrate 120 are provided at the four corners of the sealing material 102, and are electrically connected to the connection terminals 106 through wiring. .

As shown in FIG. 4, the liquid crystal device 100 of the present embodiment includes a TFT array substrate 110, a counter substrate 120 disposed to face the TFT array substrate 110, and a liquid crystal layer 130 sandwiched therebetween. Yes.
The TFT array substrate 110 covers a substrate body 111 made of a light-transmitting material such as glass or quartz, a TFT (Thin Film Transistor) 118 formed on the inner side (the liquid crystal layer 130 side), a pixel electrode 112, and further covers this. An alignment base film 113, an inorganic alignment film 114, and the like are provided.
The counter substrate 120 includes a substrate body 121 made of a light-transmitting material such as glass or quartz, a common electrode 122 made of a transparent conductive material formed on the inner side (the liquid crystal layer 130 side), and an alignment base film 123 covering this. In addition, an inorganic alignment film 124 and the like are provided.
The inorganic alignment films 114 and 124 are made of silicon oxide (SiO ₂ ), but are not limited to silicon oxide, but include aluminum oxide, zinc oxide, magnesium oxide, indium tin oxide, or silicon nitride, It may be formed of titanium nitride or the like.
Note that polarizing plates 115 and 125 are arranged on the outer sides of the substrate bodies 111 and 121 (on the side opposite to the liquid crystal layer 130) in a state where the transmission axes thereof are orthogonal to each other (crossed Nicols).

In the liquid crystal device 100 described above, the inorganic alignment films 114 and 124 include the inorganic alignment films with good alignment that can be formed by the above-described sputtering apparatus 1 as the inorganic alignment films 114 and 124. Thus, the alignment state such as the pretilt angle of the liquid crystal molecules can be controlled better. In addition, a highly reliable liquid crystal device 100 which can display with high luminance and high contrast and has excellent heat resistance and light resistance is obtained.
In addition, the liquid crystal device 100 can be used for a projector equipped with light modulation means.

  DESCRIPTION OF SYMBOLS 1 ... Sputtering apparatus, 2 ... Film formation chamber, 2a ... Outer wall, 3 ... Sputtering chamber, 4 ... Substrate supply chamber, 5 ... Substrate collection chamber, 6 ... Substrate holder, 7 ... Moving means, 8 ... Cooling means, 9 ... Cooling Circulating means, 10 ... target, 11 ... backing plate, 12a ... inner magnet, 12b ... outer magnet, 13 ... yoke, 14 ... reactive gas supplying means, 15 ... sputtering gas supplying means, 16 ... insulating plate, 17 ... flange part, 18a, 18b ... side plate, 19 ... O-ring, 20 ... box, 21 ... first opening, 22 ... second opening, 23 ... mounting portion, 25 ... control plate, 26 ... opening, 28, 29 ... gate Valves 30 ... Exhaust control device 100 ... Liquid crystal device 101 ... Image display area 102 ... Seal material 103 ... Scanning line driving circuit 104 ... Data line driving circuit 105 ... Inter-substrate conduction unit 106 Connection terminal, 110 ... TFT array substrate, 111 ... substrate body, 112 ... pixel electrode, 113 ... alignment base film, 114 ... inorganic alignment film, 115 ... polarizing plate, 118 ... TFT, 120 ... counter substrate, 121 ... substrate body, 122: common electrode, 123: alignment base film, 124: inorganic alignment film, 125: polarizing plate, 130: liquid crystal layer.

Claims (5)

A sputtering chamber having a substrate holder for holding a substrate and provided with a substrate holder so that the substrate holder can be transported and into which a reaction gas is introduced; and a sputtering chamber in which a target is placed in communication with the deposition chamber. A sputtering apparatus for forming a reaction product film on the substrate by a reaction between the sputtered particles released from the chamber into the film forming chamber and the reaction gas,
The target is disposed obliquely with respect to the transport path of the substrate holder;
A box having a first opening larger than the outer periphery of the target is provided in the sputtering chamber on one surface formed in parallel with the surface of the target, and the surface of the target passes through the first opening of the box. A sputtering apparatus, wherein a second opening through which the sputtering particles pass is provided in a part of the surface of the box facing the inner surface of the box and facing the target. The sputtering apparatus according to claim 1,
A sputtering apparatus in which a sputtering gas is directly supplied into the box of the sputtering chamber. The sputtering apparatus according to claim 2, wherein
Sputtering gas is supplied into the box from near the upper surface of the target. In the sputtering apparatus as described in any one of Claims 1 thru | or 3,
A sputtering apparatus, wherein a control plate for selectively passing a part of the sputtering particles is provided between the substrate holder of the film formation chamber and the sputtering chamber. An apparatus for manufacturing a liquid crystal device comprising a liquid crystal layer sandwiched between a pair of opposing substrates, wherein an inorganic alignment film is formed on the inner surface side of at least one of the substrates,
An apparatus for manufacturing a liquid crystal device, comprising: the sputtering apparatus according to claim 1, wherein the inorganic alignment film is formed by the sputtering apparatus.

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