JP2011074480A - Sputtering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sputtering apparatus capable of catching sputtering particles flying around a target. <P>SOLUTION: The sputtering apparatus includes: a film-forming chamber 3 provided with a substrate holder 8 for retaining a substrate 2; a sputtering particle releasing part 4 which is connected with the film-forming chamber 3 and has a first target 12 and a second target 13 arranged opposite to each other in a housing 14; and a deposition preventive cover 25 which covers lateral surfaces of the first target 12 and the second target 13, an outer circumferential part 12c of a release surface 12a for releasing sputtering particles 31 and an outer circumferential part of a release surface 13a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sputtering apparatus, and more particularly to a deposition cover that prevents adhesion of sputtered particles to an unnecessary portion in an opposed target sputtering apparatus.

  Conventionally, in order to improve the reliability of alignment films used in liquid crystal devices and the like, inorganic alignment films have been studied. Patent Document 1 discloses a facing target type sputtering apparatus for forming an inorganic alignment film (inorganic alignment film). According to this, the sputtering apparatus was provided with a film forming chamber in which a substrate was accommodated and a sputtered particle emitting part. In the sputtered particle emitting portion, a pair of targets are arranged opposite to each other with a predetermined interval in the vacuum chamber. Plasma is formed in the facing space where the target faces, and sputtered particles are emitted. A substrate is disposed on the side of the facing space, and a thin film is formed on the substrate using sputtering particles flying from the facing space.

  Sputtered particles are emitted from the target in the sputtering apparatus. Therefore, Patent Document 2 discloses a method for regulating the sputtered particles emitted from the target. According to this, an anti-adhesion plate (hereinafter referred to as an anti-adhesion cover) was disposed covering the periphery of the target. And the adhesion cover was arrange | positioned in the direction which does not want to radiate | sputter sputtering particles, and it was made for sputtering particles to adhere to an adhesion cover.

JP 2007-286401 A JP 2006-134738 A

  In such a facing target type sputtering apparatus, sputtering particles are emitted from one target toward the other target. In some cases, some of the sputtered particles pass between the target and the deposition cover and adhere to the periphery of the target. Then, after sputtered particles are deposited around the target, the particles may be peeled off to generate debris. If this film peeling piece adheres to the substrate accommodated in the film forming chamber, the quality of the film formed on the substrate deteriorates and becomes defective. Therefore, there has been a demand for a sputtering apparatus in which sputtering particles flying around the target are captured.

  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 includes: a film formation chamber including a substrate holder that holds a substrate; and a sputtering particle emitting unit that communicates with the film formation chamber and that has a pair of targets disposed in a housing so as to face each other. A counter-target type sputtering apparatus provided with an adhesion cover that covers a side surface of the target and an outer peripheral portion of an emission surface from which the target emits sputtering particles.

  According to this sputtering apparatus, a pair of targets are disposed facing each other in the housing. Sputtered particles emitted from one target fly toward the other target. Then, the sputtered particles adhere to the other target or deposition cover. The protective cover covers the outer periphery of the discharge surface. Therefore, it is difficult for the sputtered particles flying toward the target to enter between the emission surface and the deposition cover. Furthermore, the protective cover covers the side of the target. Therefore, the sputtered particles that have entered between the emission surface and the deposition cover adhere to the deposition cover that covers the side surface of the target. As a result, the deposition cover can capture the sputtered particles flying around the target.

[Application Example 2]
In the sputtering apparatus according to the application example described above, an electrode that supports the target is provided, and a distance between the deposition cover and the target or the electrode is a thickness of a film deposited inside the film formation chamber or the sputtering particle emitting unit. It is characterized by being larger.

  According to this sputtering apparatus, even if the peeled film adheres to the deposition cover, the target, and the electrode, it is possible to prevent electric leakage from occurring between the deposition cover and the target and between the deposition cover and the electrode. .

[Application Example 3]
In the sputtering apparatus according to the application example described above, the deposition cover has an adsorption surface that adsorbs the sputtering particles in a direction intersecting the side surface at a location facing the side surface of the target.

  According to this sputtering apparatus, the deposition cover has an adsorption surface in a direction intersecting with the side surface of the target. Even when the thickness of the target is thin, it is possible to widely arrange the suction surface at a location facing the side surface of the target. When the adsorption surface is narrow, the sputtered particles are deposited and peeled off, so that the film peels off easily. In this application example, since the adsorption surface can be widened, it is possible to make it difficult for film debris to be generated from the adsorption surface.

[Application Example 4]
In the sputtering apparatus according to the application example described above, the deposition cover has an opening formed at a location facing the erosion region where the target emits the sputtering particles.

  According to this sputtering apparatus, a large amount of sputtered particles are released from the erosion region, and an opening is formed in the deposition cover where the sputtered particles pass. Therefore, it is possible to cover the target without preventing the emitted sputtered particles from traveling toward the opposite target.

[Application Example 5]
In the sputtering apparatus according to the application example described above, a part of the casing disposed on either one of the pair of targets is formed so as to be removable from the outside of the casing including the target, and the deposition cover Is formed to be removable from the inside of the housing.

  According to this sputtering apparatus, a part of the pair of targets in the sputtered particle emitting portion where the target on one side is arranged is formed to be removable from the outside of the housing. When replacing the target, a part of the casing in which the target on one side is arranged is removed. A hole is opened in the housing after removal. Next, the protective cover can be removed and the protective cover can be replaced through the opened hole. Therefore, the replacement work of the protective cover is easy and can be performed in a short time and reliably.

Schematic which shows the structure of the sputtering device concerning 1st Embodiment. Sectional drawing which shows the principal part which shows a deposition cover. The principal part sectional view which shows the adhesion prevention cover concerning a 2nd embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. In each drawing used for the following description, the ratio of dimensions of each member is appropriately changed so that each member can be recognized.

(First embodiment)
FIG. 1 is a schematic view showing the configuration of the sputtering apparatus of this embodiment. The sputtering apparatus is used, for example, when an inorganic alignment film is formed on a substrate that is a constituent member of a liquid crystal device. As shown in FIG. 1, the sputtering apparatus 1 includes a film forming chamber 3 that accommodates a substrate 2, and a sputtering particle emitting unit 4 that generates plasma and emits sputtering particles from a target. The film forming chamber 3 is long in one direction, and the longitudinal direction of the film forming chamber 3 is defined as the X direction. In the horizontal plane, the direction orthogonal to the X direction is defined as the Y direction, and the vertical direction is defined as the Z direction. The film forming chamber 3 and the sputtered particle emitting unit 4 are formed so as to be airtight inside, and each inside is used in a reduced pressure atmosphere. The sputtered particles refer to the constituent atoms of the target that pop out due to the sputtering phenomenon.

  An exhaust control device 5 that controls the chamber pressure in the film forming chamber 3 and the sputtered particle emitting unit 4 is connected to the film forming chamber 3. The exhaust control device 5 includes a rotary pump and a cryopump for obtaining a desired degree of vacuum. Further, a reactive gas supply means 7 for supplying oxygen gas 6 as a reactive gas to the film forming chamber 3 is installed in connection with the film forming chamber 3. Sputtered particles emitted from the sputtered particle emitting unit 4 fly onto the substrate 2 accommodated in the film forming chamber 3. Then, the sputtered particles on the substrate 2 react with the oxygen gas 6 to form an inorganic alignment film. The reactive gas supply means 7 is arranged in the −X direction, and the exhaust control device 5 is arranged in the + X direction. The oxygen gas 6 supplied from the reaction gas supply means 7 flows from the −X direction side of the film forming chamber 3 to the + X direction side. At this time, the oxygen gas 6 flows to the exhaust control device 5 side through between the sputtered particle emitting unit 4 and the substrate 2.

  A substrate holder 8 that holds the substrate 2 is installed in the film forming chamber 3. Then, the substrate holder 8 holds the substrate 2 so that the film formation surface 2a, which is the surface to be processed of the substrate 2, faces the sputtering particle emitting portion 4 and is in the horizontal direction. The substrate holder 8 is connected to moving means 9 for conveying the substrate holder 8. The moving means 9 has a linear motion mechanism and transports the substrate 2 at a constant speed in the X direction in the figure. Then, a high-quality inorganic alignment film is formed on the substrate 2 by the sputtered particles emitted from the sputtered particle emitting unit 4.

  The substrate holder 8 is provided with a heater (not shown) for heating the held substrate 2. Further, the substrate holder 8 is provided with a cooling unit 10 for cooling the held substrate 2. The cooling unit 10 is connected to the refrigerant circulation unit 11, and the refrigerant circulation unit 11 cools the substrate holder 8 by circulating the refrigerant with the cooling unit 10. The heater is configured to maintain the substrate holder 8 at a predetermined temperature by heating the substrate holder 8 and the cooling unit 10 cooling the substrate holder 8.

  Further, a load lock chamber (not shown) is installed on one side or both sides of the film forming chamber 3 in the X direction. The load lock chamber and the film forming chamber 3 are connected via a gate valve that hermetically closes the chamber. Further, an exhaust control device for adjusting the load lock chamber to a vacuum atmosphere is arranged. By controlling the opening and closing of the gate valve and the atmospheric pressure of the load lock chamber, the substrate 2 can be loaded and unloaded while the vacuum degree of the film forming chamber 3 is maintained. The sputtering apparatus 1 is configured so that the substrate 2 can be efficiently loaded and unloaded without releasing the film deposition chamber 3 to the atmosphere when the substrate 2 is loaded into and unloaded from the film deposition chamber 3.

  The sputtered particle emitting unit 4 includes a first target 12 and a second target 13 which are arranged to face each other, and the sputtering apparatus 1 is a counter target type. The sputtered particle emitting unit 4 has a rectangular parallelepiped box-shaped casing 14, and the casing 14 is opened only on the connection surface with the film forming chamber 3. The film forming chamber 3 and the sputtered particle emitting unit 4 are attached via the connection unit 15.

  A first target 12 and a second target 13 are disposed substantially parallel to each other inside the casing 14 of the sputtered particle emitting unit 4. The planar direction of the first target 12 and the second target 13 is defined as the Xa direction. Then, the sputtered particle emitting portion 4 is arranged so that the angle of the Xa direction with respect to the Z direction which is the normal direction of the film formation surface of the substrate 2 is a predetermined angle θ. The predetermined angle θ is not particularly limited, and may be set according to the surface shape of the film formed on the substrate 2. The predetermined angle θ is preferably set through preliminary experiments.

  In the present embodiment, the substrate holder 8 during film formation is transported from the start point side in the −X direction toward the end point side in the + X direction. The first target 12 and the second target 13 are arranged to be inclined toward the end point of conveyance of the substrate holder 8. The first target 12 is provided closer to the starting point of conveyance of the substrate holder 8, and the second target 13 is provided closer to the end point of conveyance of the substrate holder 8. The first target 12 and the second target 13 are made of a material containing constituent substances formed on the substrate 2. For example, when an inorganic alignment film is formed on the substrate 2, the first target 12 and the second target 13 are made of a material having good electrical conductivity in which boron, phosphorus or the like is doped into a material mainly made of silicon. Further, the first target 12 and the second target 13 are plate-like ones whose width in the Y direction is longer than the width of the substrate 2. Then, the sputtered particles fly over the entire width of the substrate 2 in the Y direction which is the width direction of the substrate 2.

  The first target 12 is mounted on a backing plate 16 as an electrode having a flat surface. The backing plate 16 is fastened to the insulating plate 17 from the inside of the housing 14 by mounting screws 19. The insulating plate 17 is fastened to one surface of the housing 14 from the inside by a mounting screw 19. Since the insulating plate 17 is disposed between the housing 14 and the backing plate 16, no current flows between the housing 14 and the backing plate 16. The backing plate 16 is installed through a hole 14 a formed in one surface of the housing 14, and the plate back surface portion 16 a of the backing plate 16 is disposed so as to protrude outside the housing 14. Since the O-ring 18 is installed between the backing plate 16, the insulating plate 17, and the housing 14, the inside of the housing 14 is kept airtight.

  The second target 13 is mounted on a backing plate 20 as an electrode having a flat surface. The backing plate 20 is fastened to the insulating plate 24 from the inside of the housing 14 by mounting screws 19. The insulating plate 24 is fastened to the target assembly plate 23 from the inside by a mounting screw 19. Since the insulating plate 24 is disposed between the target assembly plate 23 and the backing plate 20, no current flows between the target assembly plate 23 and the backing plate 20.

  The target assembly plate 23 is fastened to the housing 14 from the outside of the housing 14 by mounting screws 19 so as to close the holes 14b formed in the housing 14. The backing plate 20 is installed through a hole 23 a formed in the target assembly plate 23, and the plate back surface portion 20 a of the backing plate 20 is disposed so as to protrude outside the housing 14. An O-ring 18 is installed between the backing plate 20, the insulating plate 24, the target assembly plate 23, and the housing 14, so that the inside of the housing 14 is kept airtight.

  An adhesion cover 25 is disposed between the first target 12 and the second target 13. The protective cover 25 has a square cross section and is formed in a long cylindrical shape in the Xa direction, and a bottom 25a is formed at the end in the -Xa direction. The bottom 25 a is fastened to the housing 14 from the outside by an attachment screw 19 via the O-ring 18, and the inside of the housing 14 is kept airtight by the O-ring 18.

  In the first target 12, the surface on the second target 13 side is an emission surface 12a that emits sputtering particles. Similarly, in the second target 13, the surface on the first target 12 side is an emission surface 13a that emits sputtering particles. An opening 25 b is formed at a location facing the first target 12 and the second target 13 in the deposition cover 25. The sputtering particles emitted from the emission surface 12a of the first target 12 and the emission surface 13a of the second target 13 pass between the first target 12 and the second target 13 through the opening 25b. Can do.

  Part of the sputtered particles emitted from the first target 12 travels toward the second target 13 and is deposited on the second target 13. Similarly, some of the sputtered particles emitted from the second target 13 travel toward the first target 12 and are deposited on the first target 12. Some of the sputtered particles travel toward the film forming chamber 3. An opening is formed on the deposition cover 3 side of the deposition cover 25, and this opening is referred to as a discharge opening 25c. Some of the sputtered particles emitted from the first target 12 and the second target 13 fly toward the film forming chamber 3 through the emission opening 25 c.

  Sputtered particles arriving at the deposition cover 25 are deposited on the deposition cover 25. Since the inside of the housing 14 is covered with the deposition cover 25, it is difficult for the sputtered particles to deposit in places other than the first target 12, the second target 13, and the deposition cover 25 in the housing 14.

  The sputtered particle emitting unit 4 includes a sputtering gas supply means 26. When the opposite side of the film formation chamber 3 is the bottom surface portion 14c in the sputtering particle emitting portion 4, the sputtering gas supply means 26 allows discharge argon gas to flow from the bottom surface portion 14c. The sputtering gas that has flowed in is configured to flow from the bottom surface portion 14 c of the housing 14 to the film forming chamber 3 through the pair of opposing first targets 12 or second targets 13.

  The backing plate 16 and the backing plate 20 have a function of electrodes, and a power source (not shown) that outputs a square wave or a sine wave is connected to them. A space where the first target 12 and the second target 13 face each other is defined as a plasma generation region. When a voltage is applied between the backing plate 16 and the backing plate 20 from the power source in a state where the sputtering gas is supplied, the sputtering particle emitting unit 4 generates plasma Pz in the plasma generation region.

  A cooling unit (not shown) for cooling the first target 12 is installed in the backing plate 16. A pipe 27 is provided on the plate back surface portion 16 a so as to be connected to the cooling part, and a refrigerant circulation part 28 is provided so as to be connected to the pipe 27. The refrigerant circulating unit 28 cools the first target 12 through the cooling unit by circulating the refrigerant. Similarly, a cooling unit (not shown) for cooling the second target 13 is installed in the backing plate 20. A pipe 29 is provided on the plate back surface portion 20 a so as to be connected to the cooling part, and a refrigerant circulation part 30 is provided so as to be connected to the pipe 29. The refrigerant circulation unit 30 cools the second target 13 through the cooling unit by circulating the refrigerant.

  Magnetic field generation means (not shown) is arranged from the back side so as to surround the first target 12 and the second target 13. The magnetic field generating means is composed of a permanent magnet, an electromagnet, or a combination of these, and forms a magnetic field in the Za direction surrounding the first target 12 and the second target 13. This magnetic field restrains electrons and ionic substances contained in the plasma Pz within the plasma generation region. That is, the magnetic field generating means is a restraining means for electrons and ionic substances.

  Next, a method for forming an inorganic alignment film on the substrate 2 using the sputtering apparatus 1 will be described. First, argon gas is introduced from the sputtering gas supply means 26. Next, a plasma Pz is generated in a space between the first target 12 and the second target 13 by applying a high voltage having a pulse waveform or a sine waveform to the backing plates 16 and 20. By causing argon ions in the plasma atmosphere to collide with the first target 12 and the second target 13, the alignment film material (silicon) is sputtered from the first target 12 and the second target 13 as sputtering particles. Further, among the sputtering particles contained in the plasma Pz, only the sputtering particles flying from the plasma Pz to the emission opening 25c are emitted to the film forming chamber 3 side.

  An alignment film made of silicon oxide is formed on the substrate 2 by causing the sputtered particles flying from the sputtered particle emitting unit 4 to react with the oxygen gas 6 flowing through the film forming chamber 3 on the substrate 2. Then, an inorganic alignment film having a columnar structure aligned in one direction is formed on the substrate 2.

  As the sputtering apparatus 1 is used, the target is consumed, and sputtering particles are deposited on the deposition cover 25. Therefore, the target and the deposition cover 25 are periodically replaced. Here, the case where the target and the cover 25 are exchanged as a maintenance operation will be described. First, the operator removes the pipe 29 from the backing plate 20. Subsequently, the operator removes the mounting screw 19 that fixes the target assembly plate 23 to the housing 14 from the outside of the housing 14. Next, the operator removes the target assembly plate 23 from the housing 14. Subsequently, the worker moves the target assembly plate 23 onto a work desk (not shown). Next, the operator replaces the second target 13 mounted on the backing plate 20 on the work desk.

  Next, the operator removes the mounting screw 19 that fixes the deposition cover 25 to the housing 14 from the outside of the housing 14. Next, the operator removes the deposition cover 25 from the housing 14 and removes it from the hole 14 b of the housing 14. Subsequently, the operator removes the pipe 27 from the backing plate 16. Next, the operator removes the mounting screw 19 that fixes the backing plate 16 to the insulating plate 17. At this time, the operator inserts a tool into the housing 14 from the hole 14b of the housing 14 and operates it. Next, the operator removes the backing plate 16 from the insulating plate 17 and removes it from the hole 14 b of the housing 14. Subsequently, the worker moves the backing plate 16 onto a work desk (not shown). Next, the operator replaces the first target 12 mounted on the backing plate 16 on the work desk.

  Next, the operator moves the backing plate 16 into the housing 14 through the hole 14 b of the housing 14. Subsequently, the operator aligns the backing plate 16 with the insulating plate 17, and then fastens the backing plate 16 to the insulating plate 17 with the mounting screws 19. Subsequently, the operator moves the deposition cover 25 to be installed into the housing 14 through the hole 14 b of the housing 14. Subsequently, the operator aligns the bottom 25 a of the deposition cover 25 with the bottom surface portion 14 c of the casing 14, and then fixes the deposition cover 25 to the casing 14 with the mounting screws 19.

  Next, the operator aligns the target assembly plate 23 with the hole 14 b of the housing 14, and then fastens the target assembly plate 23 to the housing 14 with the mounting screws 19. With the above operation, the replacement of the target and the deposition cover 25 is completed.

  FIG. 2 is a cross-sectional view of the principal part showing the deposition cover 25, and FIG. 2 (a) is a view as seen from A-A 'in FIG. As shown in FIG. 2A, the opening 25b of the deposition cover 25 is formed in a rectangular shape that is long in the Y direction. An opening 25b is formed in the deposition cover 25 at a location facing the erosion region 12b that emits a large amount of sputtered particles in the first target 12. Sputtered particles are discharged into the inside of the deposition cover 25 through the opening 25b.

  The opening 25 b of the deposition cover 25 is formed inside the outer peripheral portion 12 c of the first target 12. Therefore, the deposition cover 25 is formed so as to cover the outer peripheral portion 12 c of the first target 12. The opening 25 b at the location facing the second target 13 in the deposition cover 25 is also formed in the same shape as the opening 25 b at the location facing the first target 12. An opening 25 b is formed in the deposition cover 25 at a location facing the erosion region of the second target 13. Further, the deposition cover 25 is formed so as to cover the outer periphery of the second target 13.

  FIG. 2B is an enlarged view of the vicinity of the target in FIG. As shown in FIG. 2B, the deposition cover 25 covers a location facing the outer peripheral portion 12 c of the first target 12. Further, a side cover portion 25 d is disposed so as to protrude from the deposition cover 25 at a location facing the side surface 12 d of the first target 12. The side cover portion 25d is disposed so as to cover the four side surfaces 12d of the first target 12. The entire surface of the deposition preventive cover 25 is an adsorption surface that has been processed so that the sputtered particles 31 are easily adsorbed.

  A part of the sputtered particles 31 flying from the second target 13 toward the first target 12 passes through the opening 25b on the first target 12 side. The sputtered particles 31 land on the emission surface 12 a of the first target 12. A part of the sputtered particles 31 passes through the opening 25b on the first target 12 side. Then, the sputtered particles 31 traveling at an angle close to parallel to the emission surface 12a land on the side cover portion 25d. The sputtered particles 31 flying from the second target 13 toward the first target 12 land on the first target 12 or the deposition cover 25. Accordingly, since the sputtered particles 31 are unlikely to pass between the first target 12 and the deposition cover 25, it is difficult for the sputtered particles 31 to be deposited on the backing plate 16.

  The shortest distance between the discharge surface 12 a of the first target 12 and the deposition cover 25 is defined as a discharge surface cover distance 32. The shortest distance between the side surface 12d of the first target 12 and the side surface cover portion 25d is defined as a side surface cover distance 33. Further, the shortest distance between the backing plate 16 and the side cover portion 25d of the deposition cover 25 is defined as an electrode cover distance 34. If the film formation is continued, the sputtered particles 31 may be deposited in the film forming chamber 3 and the sputtered particle emitting unit 4 to form a film, which may be peeled off. Particularly in the case of facing target sputtering, a large amount of sputtered particles are emitted from the target on the opposite side, so this concern is great. The size of the peeled film pieces is not uniform, but when a thickly deposited film peels off while self-destructing, most of the pieces are as small as or smaller than the thickness of the deposited film. . In facing target sputtering, the deposition cover is often continuously used until the film thickness becomes 1 mm or more, and when film peeling does not occur, it can be further used up to a film thickness of about 2 mm. Here, each of the distance 32 between the discharge surface covers, the distance 33 between the side covers, and the distance 34 between the electrode covers is set larger than the film thickness of the deposited film. Therefore, even when the film peels off and the debris enters between the first target 12 and the deposition cover 25, it is difficult for the fragments to adhere so as to bridge the first target 12 and the deposition cover 25. Similarly, even when a film peeling piece enters between the backing plate 16 and the deposition cover 25, it is difficult for the fragment to adhere so as to bridge the backing plate 16 and the deposition cover 25.

  The shape of the deposition cover 25 on the second target 13 side is formed in the same shape as the shape on the first target 12 side. Accordingly, since the sputtered particles 31 are unlikely to pass between the second target 13 and the deposition cover 25, the sputtered particles 31 are difficult to deposit on the backing plate 20. Then, the film is peeled off so that the second target 13 and the deposition cover 25 are cross-linked. Further, the film peels off so that the second target 13 and the backing plate 20 are cross-linked.

As described above, this embodiment has the following effects.
(1) According to the present embodiment, the first target 12 and the second target 13 are disposed to face each other in the housing 14. Sputtered particles 31 emitted from one target fly toward the other target. Then, the sputtered particles 31 adhere to the other target and the deposition cover 25. On the first target 12 side, the deposition cover 25 covers the outer peripheral portion 12c of the emission surface 12a. Therefore, the sputtered particles 31 flying toward the first target 12 are unlikely to enter between the emission surface 12 a and the deposition cover 25. Further, the deposition cover 25 covers the side surface 12 d of the first target 12. Accordingly, the sputtered particles 31 that have entered between the emission surface 12 a and the deposition cover 25 adhere to the deposition cover 25 that covers the side surface 12 d of the first target 12. As a result, the deposition cover 25 can capture the sputtered particles 31 flying around the first target 12. About this content, the same effect is acquired also in the deposition cover 25 by the side of the 2nd target 13. FIG.

  (2) According to the present embodiment, film peeling fragments are difficult to adhere so as to bridge the first target 12 and the deposition cover 25. Further, the film is peeled off so that the first target 12 and the backing plate 16 are cross-linked so that the fragments are not easily attached. Therefore, even if film peeling fragments adhere to the deposition cover 25, the first target 12, and the backing plate 16, between the deposition cover 25 and the first target 12 and between the deposition cover 25 and the backing plate 16. It is possible to prevent electric leakage.

  (3) According to this embodiment, the opening part 25b is formed in the adhesion cover 25 in the place facing the erosion area | region 12b. That is, the opening 25b is formed in the deposition cover 25 at the place where the sputtered particles 31 pass. Therefore, the first target 12 and the second target 13 can be covered without hindering the emission of the sputtered particles 31.

  (4) According to the present embodiment, the target assembly plate 23 on which the second target 13 is arranged is formed to be removable from the outside of the housing 14. When the target is exchanged, the target can be exchanged by removing the target assembly plate 23 on which the second target 13 is disposed and removing the backing plate 16 and the cover 25 through the opened hole 14b. The removed target assembly plate 23 and backing plate 16 can be replaced on the work desk. Therefore, replacement of the first target 12, the second target 13, and the deposition cover 25 is easy, and can be performed in a short time and reliably.

(Second Embodiment)
Next, an embodiment of the sputtering apparatus will be described with reference to a cross-sectional view of the main part showing the deposition cover of FIG. The present embodiment is different from the first embodiment in that the shape of the deposition cover 25 is different. Note that description of the same points as in the first embodiment is omitted.

  That is, in this embodiment, as shown in FIG. 3, the sputtering apparatus 37 includes the first target 12 mounted on the backing plate 16. An anti-adhesion cover 38 is disposed at a location facing the backing plate 16. The surface of the deposition cover 38 is an adsorption surface that has been processed so that the sputtered particles 31 are easily adsorbed. The protective cover 38 includes an outer peripheral cover portion 38 a, and the outer peripheral cover portion 38 a covers a place facing the outer peripheral portion 12 c of the first target 12. The outer peripheral cover portion 38a is formed with an opening 38b at a location facing the erosion region 12b so as not to prevent the sputtered particles 31 emitted from the first target 12 from passing toward the second target 13. ing.

  A first side cover portion 38c having a surface parallel to the side surface 12d is disposed at a location facing the side surface 12d of the first target 12. Furthermore, a second side surface cover portion 38d having a suction surface in a direction orthogonal to the side surface 12d is disposed at a location facing the side surface 12d of the first target 12. The first side surface cover part 38c and the second side surface cover part 38d are arranged so as to cover the four side surfaces 12d of the first target 12.

  A part of the sputtered particles 31 flying from the second target 13 toward the first target 12 passes through the opening 38b on the first target 12 side. The sputtered particles 31 land on the emission surface 12 a of the first target 12. A part of the sputtered particles 31 passes through the opening 38b on the first target 12 side. Then, the sputtered particles 31 traveling at an angle nearly parallel to the emission surface 12a land on the first side surface cover portion 38c or the second side surface cover portion 38d. Then, the sputtered particles 31 flying from the second target 13 toward the first target 12 land on the first target 12 or the deposition cover 38. Therefore, it is difficult for the sputtered particles 31 to be deposited on the backing plate 16.

  The shortest distance between the discharge surface 12a of the first target 12 and the outer peripheral cover portion 38a is defined as a discharge surface cover distance 39. Then, the shortest distance between the side surface 12d of the first target 12 and the second side surface cover portion 38d is set as a distance 40 between the side surface covers. Further, the shortest distance between the backing plate 16 and the second side surface cover portion 38d is defined as an electrode cover distance 41. The distances 39 between the discharge surface covers, 40 between the side covers, and 41 between the electrode covers are set to be larger than the film thickness of the deposited film. Therefore, even when a film peeling piece enters between the first target 12 and the deposition cover 38, the film peeling piece is less likely to adhere so as to bridge the first target 12 and the deposition cover 38. . Similarly, even when a film peeling piece enters between the backing plate 16 and the deposition cover 38, the film peeling piece is difficult to adhere so as to bridge the backing plate 16 and the deposition cover 38.

  The shape on the second target 13 side in the deposition cover 38 is formed in the same shape as the first target 12 side. Therefore, the film is peeled off so that the second target 13 and the deposition cover 38 are cross-linked and it is difficult for the fragments to adhere. Furthermore, the film is peeled off so that the backing plate 20 and the adhesion-preventing cover 38 are cross-linked, making it difficult for debris to adhere.

  The shape of the deposition cover 38 on the second target 13 side is formed in the same shape as the shape on the first target 12 side. Accordingly, since the sputtered particles 31 are unlikely to pass between the second target 13 and the deposition cover 38, the sputtered particles 31 are difficult to deposit on the backing plate 20. Then, the film is peeled off so that the second target 13 and the deposition cover 38 are cross-linked, and the fragments are less likely to adhere. Further, the film is peeled off so that the second target 13 and the backing plate 20 are cross-linked, and it is difficult for the fragments to adhere.

As described above, this embodiment has the following effects.
(1) According to the present embodiment, the deposition cover 38 includes the second side surface cover portion 38 d having a suction surface in a direction orthogonal to the side surface 12 d of the first target 12. Even when the thickness of the first target 12 is thin, it is possible to widen the suction surface at a location facing the side surface 12d of the first target 12. When the adsorption surface is narrow, the sputtered particles 31 are deposited and peeled off, so that film peeling fragments are easily generated. In the present embodiment, since the second side surface cover portion 38d is installed in a direction in which the suction surface is orthogonal to the side surface 12d of the first target 12, the suction surface can be widened. As a result, film peeling fragments can be made difficult to occur.

In addition, this embodiment is not limited to embodiment mentioned above, A various change and improvement can also be added. A modification will be described below.
(Modification 1)
In the first embodiment, a case where silicon as a sputtered particle is reacted with oxygen gas to form a silicon oxide film on the substrate 2 has been described. As a target, for example, silicon oxide (SiOx) is used. An inorganic alignment film made of silicon oxide or aluminum oxide can be formed on the substrate 2 using aluminum oxide or aluminum oxide (AlOy or the like). This modification can also be applied to the second embodiment.

(Modification 2)
In the first embodiment, the sputtered particle emitting portion 4 is arranged so that the angle in the Xa direction with respect to the Z direction, which is the normal direction of the film formation surface of the substrate 2, is a predetermined angle θ. The predetermined angle θ is not particularly limited. For example, the predetermined angle θ may be 0 degree. At this time, the sputtering apparatus 1 can land the sputtering particles 31 from a direction orthogonal to the film formation surface 2 a of the substrate 2. The film characteristics can be changed by changing the predetermined angle θ. This modification can also be applied to the second embodiment.

(Modification 3)
In the second embodiment, the second side cover portion 38d is disposed so as to be orthogonal to the side surface 12d. The second side cover portion 38d may be disposed obliquely with respect to the side surface 12d. It is only necessary to provide a large area of the adsorption surface to which the sputtered particles 31 adhere.

  DESCRIPTION OF SYMBOLS 1,37 ... Sputtering apparatus, 2 ... Substrate, 3 ... Film formation chamber, 4 ... Sputtering particle discharge | release part, 8 ... Substrate holder, 12 ... 1st target, 12a ... Release surface, 12b ... Erosion area | region, 12c ... Outer peripheral part, 12d ... side face, 13 ... second target, 14 ... housing, 16, 20 ... backing plate as electrode, 25b, 38b ... opening, 25, 38 ... deposition cover, 31 ... sputtering particles.

Claims (5)

An opposed target type sputtering apparatus comprising: a film forming chamber provided with a substrate holder for holding a substrate; and a sputtering particle emitting unit that communicates with the film forming chamber and has a pair of targets facing each other in a housing. And
A sputtering apparatus comprising an adhesion cover covering a side surface of the target and an outer peripheral portion of an emission surface from which the target emits sputtering particles. The sputtering apparatus according to claim 1,
An electrode for supporting the target;
The sputtering apparatus according to claim 1, wherein a distance between the deposition cover and the target or the electrode is larger than a thickness of a film deposited in the film forming chamber or the sputtering particle emitting unit. The sputtering apparatus according to claim 2,
The sputtering apparatus according to claim 1, wherein the deposition cover has an adsorption surface that adsorbs the sputtering particles in a direction crossing the side surface at a location facing the side surface of the target. The sputtering apparatus according to claim 3,
The sputtering apparatus is characterized in that an opening is formed at a location where the target is opposed to an erosion region where the target emits the sputtered particles. The sputtering apparatus according to claim 4,
A part of the casing disposed on one of the pair of targets is formed so as to be removable from the outside of the casing including the target, and the deposition cover is removable from the inside of the casing A sputtering apparatus characterized by being formed.

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