JP2016141825A - Sputtering apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sputtering apparatus capable of depositing a low damage film by sputtering.SOLUTION: A sputtering apparatus comprises: an electrode 310 having a holding part 311 for holding a target 50 and applying a potential to the target 50 through the holding part 311; a pair of first magnets 331a and 332a and a pair of second magnets 331b and 332b arranged apart from each other in a direction along a substrate arrangement surface SS having a substrate to be arranged so as to sandwich a space SP between the substrate arrangement surface SS and the holding part 311; and a shield 340 arranged between the substrate arrangement surface SS and the holding part 311. The target 50 has first and second plate-like portions 51 and 52 provided in parallel on both sides of the space SP. The direction of the magnetic field formed by the pair of first magnets 331a and 332a is opposite to the direction of the magnetic field formed by the pair of second magnets 331b and 332b.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a sputtering apparatus.

  Patent Document 1 describes a box-type counter-target type sputtering apparatus including a pair of targets arranged so as to face each other so as to sandwich a space where one surface of a substrate to be processed faces. A permanent magnet is disposed on the back side of each target, and a cooling jacket is disposed between the target and the permanent magnet. Each target is assembled together with a portion constituting a cooling jacket, a permanent magnet, and the like to constitute a target portion. Each target part is fixed to a frame, respectively.

JP 2005-48227 A

  In the box type opposed target sputtering apparatus described in Patent Document 1, it is necessary to attach each of the pair of target portions to a frame. Moreover, each target portion is large because it includes a portion constituting a cooling jacket, a permanent magnet, and the like in addition to the target. Therefore, it is considered that the box type opposed target sputtering apparatus described in Patent Document 1 requires a considerable amount of time for maintenance such as target replacement. Further, in the configuration in which the cooling jacket is arranged between the permanent magnet and the target, the magnetic field generated by the permanent magnet is attenuated by the refrigerant in the cooling jacket, etc., so that it is necessary to enlarge the permanent magnet.

  An object of the present invention is to provide a sputtering apparatus and a sputtering target having a new and useful structure.

  The sputtering apparatus according to the present invention is a sputtering apparatus for forming a film on a substrate by sputtering in a chamber, and an electrode for applying a potential to the target via a holding unit for holding the target, and the substrate should be disposed. A first counter magnet portion disposed so as to sandwich a space between the substrate placement surface and the holding portion and spaced from each other in a direction along the substrate placement surface; and a substrate on which the substrate is to be placed A space between the placement surface and the holding portion is sandwiched between them, and they are separated from each other in a direction along the substrate placement surface, and separated by a predetermined distance along the first counter magnet portion and the substrate transport direction. A second counter magnet portion disposed between the first counter magnet portion and the second counter magnet portion, and the substrate disposition surface. A shield disposed at a position between the holding portion, and the target includes a first portion and a second portion provided to face each other with the space interposed therebetween, and the first counter magnet portion And the second counter magnet portion forms a magnetic field in the space in a direction perpendicular to the surfaces where the first portion and the second portion oppose each other, and the first counter magnet portion and the second counter magnet portion The opposing magnet unit forms magnetic fields in opposite directions.

  According to the present invention, a sputtering apparatus and a sputtering target having a new and useful structure are provided.

The top view which shows roughly the structure of the processing system of one Embodiment of this invention. The figure which shows the structure of the film-forming apparatus. The figure which shows the structure of the film-forming apparatus. The figure which shows the structure of the film-forming apparatus. CC sectional view taken on the line of FIG. DD sectional drawing of FIG. The figure which shows one structural example of a target. The figure which shows one structural example of a target. The figure which shows the structure of the film-forming apparatus of 2nd Embodiment.

  Hereinafter, the present invention will be described through exemplary embodiments thereof with reference to the accompanying drawings.

  FIG. 1 is a plan view schematically showing the configuration of a processing system 100 according to one embodiment of the present invention. The processing system 100 is configured as an inline processing apparatus. The in-line method refers to a method of processing a substrate while transporting the substrate through a plurality of connected chambers. In the film forming apparatus shown in FIG. 1, a plurality of chambers 111 to 130 are connected endlessly so as to form a square layout. Each of the chambers 111 to 130 is provided with a transport device that transports the substrate 1 held by the carrier 10. The adjacent chambers in the chambers 111 to 130 are connected through a gate valve. The chamber 111 is a load lock chamber in which processing for attaching the substrate 1 to the carrier 10 is performed. The chamber 116 is an unload lock chamber in which processing for removing the substrate 1 from the carrier 10 is performed.

  In order to present a more specific example, an example in which the processing system 100 is applied to a processing apparatus for manufacturing a hard disk will be described. The substrate 1 can be, for example, a metal or glass disk-like member having a hole in the center portion. The carrier 10 can be configured to hold two substrates.

  First, the unprocessed substrate 1 is attached to the leading carrier 10 in the chamber 111. The carrier 10 used in this embodiment is a type on which two substrates 1 can be mounted. The carrier 10 on which the substrate 1 is mounted moves to the chamber 117 for forming the adhesion layer, and the adhesion layer is formed on the substrate 1. During this time, two unprocessed substrates 1 are attached to the second carrier 10.

  Next, the soft magnetic layer is formed on the substrate 1 while the leading carrier 10 sequentially moves to the chambers 118, 119 and 120 for forming the soft magnetic layer. During this time, the second carrier 10 moves to the chamber 117 for forming the adhesion layer, the adhesion layer is formed on the substrate 1, and the substrate 1 is attached to the third carrier 10 in the chamber 111. . In this manner, each time the leading carrier 10 and the subsequent carrier 10 move, the substrate 1 is attached to the subsequent carrier 10 in the chamber 111.

  The leading carrier 10 holding the substrate 1 on which the soft magnetic layer is formed moves to the chamber 121 for forming the seed layer, and the seed layer is formed on the substrate 1. Thereafter, the leading carrier 10 sequentially moves to chambers 123 and 124 for forming an intermediate layer, chambers 126 and 127 for forming a magnetic film, and a chamber 129 for forming a protective film.

  Chambers 112, 113, 114, and 115 are arranged at the four corners in the rectangular layout. The chambers 112, 113, 114, and 115 are chambers including a direction changing device that changes the transport direction of the carrier 10 (substrate 1) by 90 degrees.

  The chambers 117 to 130 (excluding 112 to 114) are components of the film forming apparatus. 2 and 3 are diagrams showing a configuration of one film forming apparatus, and each of the chambers 117 to 130 (excluding 112 to 114) corresponds to the chamber 201 of FIG. FIG. 2 is a cross-sectional view of the film forming apparatus 200 taken along a plane (plane along the transport direction) orthogonal to the transport direction of the carrier 10 (substrate 1). FIG. 3 is a sectional view taken along line A-A ′ in FIG. 2. FIG. 4 shows the configuration of the peripheral portion of the target (sputtering target) 50. The film forming apparatus 200 is configured as a sputtering apparatus.

  The film forming apparatus (sputtering apparatus) 200 includes a chamber 201, a transport apparatus 230 that transports the carrier 10, and gate valves 220 disposed on the upstream side and the downstream side of the transport path of the carrier 10 by the transport apparatus 230. The chamber 201 is connected to an adjacent chamber through a gate valve 220.

  The film forming apparatus 200 includes a gas supply unit 290 and an exhaust device 202. Gas is supplied to the chamber 201 by the gas supply unit 290, and the gas in the chamber 201 is exhausted by the exhaust device 202, whereby the pressure in the chamber 201 is controlled to the target pressure.

  In this embodiment, in the chamber 201, a film is simultaneously formed by sputtering on each of the two film formation surfaces of the two substrates 1. Four targets 50 are disposed in the chamber 201. Specifically, the first target 50 opposes one surface of the first substrate, the second target 50 opposes the other surface of the first substrate, and the one surface of the second substrate. The third target 50 faces and the fourth target 50 faces the other surface of the second substrate. The film forming apparatus 200 may be configured such that a film is formed only on one substrate 1 at a time in one chamber 201.

  As illustrated in FIG. 4, the film forming apparatus 200 includes an electrode (cathode) 310 as a backing plate, a first magnet 331 (331a, 331b), a second magnet 332 (332a, 332b), and a shield 340. And. The electrode 310 includes a holding unit 311 that holds the target 50, and is configured to apply a potential to the target 50 via the holding unit 311. For example, a potential can be applied to the electrode 310 from a power source 371 via the base member 320. The power source 371 can be, for example, a pulse DC power source, but may be another power source.

  The 1st magnet 331 and the 2nd magnet 332 may be constituted by a permanent magnet, for example. The first magnet 331 and the second magnet 332 sandwich each other in the direction along the substrate placement surface SS so as to sandwich the discharge space SP between the substrate placement surface SS where the substrate 1 is to be placed and the holding unit 311. They are spaced apart. The shield 340 is arranged at a position between the first magnet 331 and the second magnet 332 and between the substrate arrangement surface SS and the holding unit 311.

  The shield 340 can be made of a nonmagnetic metal so as not to affect the magnetic field in the discharge space SP. For example, the shield 340 may be made of aluminum, which is a nonmagnetic metal, or may be made of nonmagnetic stainless steel.

  As illustrated in FIGS. 7A and 7B, the target 50 includes a first portion 51 to be disposed between the first magnet 331 and the discharge space SP, and a space between the second magnet 332 and the discharge space SP. 2nd part 52 which should be arrange | positioned, and the connection part 53 which connects the 1st part 51 and the 2nd part 52 are included. In the target 50, the connecting portion 53 is fixed to the holding portion 311. The holding part 311 has an engaging part 312 with which a fixing member 315 for fixing the target 50 is engaged. In one example, the engaging portion 312 is a screw hole, and the fixing member 315 is a screw. The fixing member 315 passes through the hole 55 provided in the connecting portion 53 of the target 50 and is screwed into the engaging portion 312. A potential is applied to the first portion 51 and the second portion 52 from the electrode 310 via the connecting portion 53.

  The structure in which the target 50 is supported by the holding portion 311 of the electrode 310 holding the connecting portion 53 among the first portion 51, the second portion 52, and the connecting portion 53 of the target 50 is that the target 50 is mounted on the electrode 310 And it is advantageous for facilitating the work of removing the target 50 from the electrode 310. The target 50 will be described later with reference to FIGS. 7A and 7B.

  FIG. 5 is a sectional view taken along the line CC of FIG. The first magnet 331 and the second magnet 332 will be described with reference to FIG. The first magnet 331 includes two first magnets 331a and 331b. The first magnets 331a and 331b are arranged side by side with an interval E (predetermined distance) along the substrate transport direction. Similarly, the second magnet 332 includes two second magnets 332a and 332b. The second magnets 332a and 332b are arranged side by side with an interval E along the substrate transport direction. The first magnet 331a and the second magnet 332a face each other across the discharge space SP. The first magnet 331b and the second magnet 332b face each other across the discharge space SP.

  FIG. 5 illustrates the magnetic poles of the first magnet 331a and the second magnet 332a. The first magnet 332a is arranged so that the south pole faces the discharge space SP, and the second magnet 332a is arranged so that the north pole faces the discharge space SP. With this arrangement, the south pole of the first magnet 331a and the north pole of the second magnet 332a are arranged to face each other, and the first portion 51 and the second portion 52 face each other (surface on the discharge space SP side). A magnetic field W1 (first magnetic field) whose direction coincides with the vertical direction is formed. In the present specification, hereinafter, the “direction in which the direction coincides with the direction perpendicular to the surface where the first portion 51 and the second portion 52 face each other (surface on the discharge space SP side)” is referred to as “the direction perpendicular to the target surface”. May be described. The first magnet 331b is arranged so that the N pole faces the discharge space SP, and the second magnet 332b is arranged so that the S pole faces the discharge space SP. With this arrangement, the N pole of the first magnet 331b and the S pole of the second magnet 332b are arranged to face each other, and a magnetic field W2 (second magnetic field) in a direction perpendicular to the target surface is formed. The first magnet 331a and the second magnet 332a that form the magnetic field W1 are referred to as “first counter magnet part M1”, and the first magnet 331b and the second magnet 332b that form the magnetic field W2 are referred to as “second counter magnet part M2”. To do.

  The distance E is desirably a distance at which a magnetic field is not formed between the two first magnets 331a and 331b. At least a magnetic field formed between the first magnets 331a and 331b or a magnetic field formed between the second magnets 332a and 332b (hereinafter referred to as a magnetic field in a direction along the target surface) is a magnetic field W1 or It is desirable that the magnetic field W1 and the magnetic field W2 are dominant magnetic fields in the discharge space SP that are sufficiently smaller than the magnetic field W2. For example, if the distance E is too close, the magnetic field in the direction along the target surface becomes larger than the magnetic field W1 or the magnetic field W2, and functions as two magnetron sputters that are just arranged opposite to each other. descend. On the other hand, if the distance E is too long, the distance between the magnets increases, so that the size of the apparatus increases and the in-plane distribution of the substrate may also decrease. By appropriately setting the distance E, a magnetic field whose direction coincides with a direction perpendicular to the first portion 51 and the second portion 52 (surface on the discharge space SP side) of the target 50 is formed in the discharge space SP. A uniform magnetic field can be formed. A uniform magnetic field in the discharge space SP has an effect of suppressing redeposition to the target 50.

  Furthermore, the bias of the plasma formed in the discharge space SP can be prevented by making the adjacent magnetic fields (magnetic field W1 and magnetic field W2) reverse. Specifically, since the force F1 moving in the center direction of the discharge space SP acts on the electrons by the magnetic field W1, the plasma is formed on the center side of the discharge space SP with respect to the magnetic field W1. Further, since the force F2 moving in the center direction of the discharge space SP acts on the electrons by the magnetic field W2, plasma is formed closer to the center of the discharge space SP than the magnetic field W2. That is, the magnetic fields W1 and W2 generate a force that brings electrons closer to the center of the discharge space SP, and plasma can be formed on the center side of the discharge space SP. The interval E can be set to a longer distance.

  In contrast to the example shown in FIG. 5, the first magnet 331a and the second magnet 332a are arranged so that the north pole of the first magnet 331a and the south pole of the second magnet 332a are opposed to each other. The first magnet 331b and the second magnet 332b may be arranged so that the south pole of the magnet 331b and the north pole of the second magnet 332b are opposed to each other. When the directions of the magnetic fields W1 and W2 are reversed, a force for separating the electrons from the center of the discharge space SP is generated. The plasma formed around the magnetic field W1 and the plasma formed around the magnetic field W2 receive a force in a direction away from each other. For this reason, the plasma formed in the discharge space SP spreads, and the in-plane distribution of the substrate can be improved.

  FIG. 6 is a sectional view taken along the line DD of FIG. The second magnets 332a and 332b are both cylindrical permanent magnets having a rectangular cross section, and a cavity 333 is formed at the center. The first magnets 331a and 331b are also permanent magnets having the same shape. By using a cylindrical magnet having a rectangular cross section, the cross sectional areas of the magnetic fields W2 and W1 can be increased. For this reason, the plasma formation range is expanded, and erosion can be made more uniform.

  In the present embodiment, an apparatus using two sets of opposing magnets for one target 50 has been described, but three or more sets may be used. Here, the set of opposing magnets is a combination of magnets that generate a magnetic field in a direction perpendicular to the target surface. In the above-described embodiment, the first magnet 331a, the second magnet 332a, the first magnet 331b, A magnet set such as a two-magnet 332b. When using three sets of opposing magnets, the direction of the magnetic poles of adjacent sets may be reversed. That is, the first magnet set 331a and the second magnet set 332a are set as a first magnet set, the first magnet 331b and the second magnet 332b are set as a second magnet set, and the first magnet set and the second magnet set are arranged in the substrate transport direction. In the state, when the third magnet set is further arranged downstream in the transport direction of the second magnet set, the direction of the magnetic field formed by the third magnet set is the same as that of the first magnet set. When the fourth magnet set is arranged further downstream of the third magnet set, the direction of the magnetic field formed by the fourth magnet set becomes the same as that of the second magnet set. Thus, by reversing the direction of adjacent magnetic fields, the plasma formed in the discharge space SP can be made uniform.

  7A and 7B show one configuration example of the target 50. FIG. The first portion 51 and the second portion 52 of the target 50 may be parallel to each other as illustrated in FIGS. 7A and 7B. Both the first portion 51 and the second portion 52 of the target 50 may have a flat plate shape. In the space between the first part 51 and the second part 52, a magnetic field having a direction from the first part 51 to the second part 52 or from the second part 52 to the first part 51 is formed.

  It is preferable that the 1st part 51, the 2nd part 52, and the connection part 53 are integrally comprised with the same material. However, the first portion 51 and the second portion 52 may be made of the same material (target material, for example, carbon), and the connecting portion 53 may be made of a material different from the material of the first portion 51 and the second portion 52. . In this case, in order to efficiently cool the first portion 51 and the second portion 52 and to supply an efficient potential to the first portion 51 and the second portion 52, the electric conductivity and the heat conductivity are reduced. The connecting portion 53 should be formed of a superior material.

  Further, the first portion 51 and the second portion 52 may be made of different materials. In this case, a film made of different materials is formed on the substrate 1, that is, simultaneous sputtering is realized.

  The shield 340 may be supplied with a potential that can prevent the connection portion 53 of the target 50 from being sputtered, for example, a ground potential. The shield 340 is disposed away from the connecting portion 53 so as not to short-circuit with the connecting portion 53.

  The holding unit 311 has a first surface S1 for holding the target and a second surface S2 opposite to the first surface S1, and the film forming apparatus 200 is on the second surface S2 side of the holding unit 311. In addition, a cooling channel 370 for cooling the electrode 310 may be provided. The cooling channel 370 may be formed between the electrode 310 (holding unit 311) and the base member 320. The first portion 51 and the second portion 52 of the target 50 are cooled by cooling the connection portion 53 of the target 50 via the holding unit 311 by the cooling medium flowing through the cooling channel 370.

  Between the first magnet 331 (331a, 331b) and the position where the first portion 51 of the target 50 is to be disposed, and the second magnet 332 (332a, 332b) and the second portion 52 of the target 50 are disposed. It is preferable that a cooling channel for flowing a cooling medium is not provided between the power position. Cooling channels are disposed between the first magnet 331 and the position where the first portion 51 of the target 50 is to be disposed, and between the second magnet 332 and the position where the second portion 52 of the target 50 is to be disposed. By not, the magnetic field generated by the first magnet 331 and the second magnet 332 can be guided to the space SP with little attenuation. This is advantageous in reducing the size of the first magnet 331 and the second magnet 332.

  The film forming apparatus 200 preferably further includes a second shield 361 between the position where the first magnet 331 and the second magnet 332 are arranged and the substrate arrangement surface SS. A block 351 may be disposed outside the first magnet 331 and the second magnet 332. The block 351 can be made of aluminum, for example. A third shield 352 may be disposed outside the block 351 so as to surround the block 351, the electrode 310, and the base member 320. The third shield 352 can be electrically connected to the second shield 361. The second shield 361 and the third shield 352 can be grounded.

  While supplying the gas from the gas supply unit 290 to the chamber 201, the exhaust device 202 exhausts the gas in the chamber 201 to control the pressure in the chamber 201 to the target pressure, while the target is supplied from the power source 371 through the electrode 310. By applying a potential to the 50 first portion 51 and the second portion 52, a discharge occurs in the space SP. The first portion 51 and the second portion 52 of the target 50 are sputtered by the ions generated thereby. As a result, a film is formed on the substrate 1 by the particles protruding from the first portion 51 and the second portion 52 of the target 50.

  FIG. 8 shows a configuration of a peripheral portion of a target (sputtering target) 50 in the second embodiment of the present invention. In the second embodiment, a positive potential is applied from the power source 372 to the shield 340. Matters not mentioned in the second embodiment can follow the described embodiment. By applying a positive potential to the shield 340, positive potential ions between the first portion 51 and the second portion 52 can be pushed out toward the substrate 1. On the other hand, the neutral particles are not affected by the potential of the shield 340. When the target 50 is made of carbon, film formation using carbon ions can be performed more efficiently. That is, neutral carbon can be prevented from adhering to the substrate 1 and the amount of carbon ions can be relatively increased on the substrate. Therefore, a carbon film with higher hardness can be formed. The magnitude of the positive potential applied from the power source 372 to the shield 340 can be adjusted. In the second embodiment, the substrate during film formation can be at a floating potential.

  Both the first portion 51 and the second portion 52 of the target 50 may have a flat plate shape. In addition, the first portion 51 and the second portion 52 of the target 50 may be parallel to each other. The first magnets 331a and 331b and the second magnets 332a and 332b are formed so as to form a magnetic field whose direction coincides with the first portion 51 and the second portion 52 (surfaces on the discharge space SP side thereof) in the vertical direction. Can be arranged. A uniform magnetic field can be formed in the discharge space SP by forming a magnetic field whose direction coincides with a direction perpendicular to the first portion 51 and the second portion 52 (the surface of the target 50 on the discharge space SP side). it can. A uniform magnetic field in the discharge space SP has an effect of suppressing redeposition to the target 50.

  The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, in order to make the scope of the present invention public, the following claims are attached.

SP discharge space
W1, W2 magnetic field
M1 1st counter magnet part (the 1st magnet 331a and the 2nd magnet 332a)
M2 Second opposing magnet section (first magnet 331b and second magnet 332b)
1 Substrate
10 Career
50 targets
51 1st part
52 Second part
53 connecting parts
100 treatment system
200 Deposition system
310 Electrode (backing plate)
331 (331a, 331b) First magnet
332 (332a, 332b) Second magnet
340 Shield
371 power supply

Claims (4)

A sputtering apparatus for forming a film on a substrate by sputtering in a chamber,
An electrode for applying a potential to the target via a holding unit for holding the target;
A first counter magnet portion disposed so as to sandwich a space between a substrate placement surface on which the substrate is to be placed and the holding portion and spaced apart from each other in a direction along the substrate placement surface;
A space between the substrate placement surface on which the substrate is to be placed and the holding portion is sandwiched and spaced apart from each other in a direction along the substrate placement surface, in the first counter magnet portion and the substrate transport direction. A second counter magnet portion disposed at a predetermined distance along the second counter magnet portion,
A shield disposed at a position between each of the first counter magnet unit and the second counter magnet unit and between the substrate mounting surface and the holding unit;
The target includes a first portion and a second portion provided to face each other across the space,
The first counter magnet part and the second counter magnet part form a magnetic field in the space in a direction perpendicular to the surfaces of the first part and the second part facing each other,
The sputtering apparatus according to claim 1, wherein the first counter magnet part and the second counter magnet part form magnetic fields in opposite directions. When the magnetic field formed by the first counter magnet part is a first magnetic field and the magnetic field formed by the second counter magnet part is a second magnetic field,
The direction of the magnetic field is set so that the first magnetic field generates a force that brings electrons closer to the space between the second opposing magnet parts,
2. The sputtering apparatus according to claim 1, wherein the direction of the magnetic field of the second magnetic field is set so as to generate a force that brings electrons closer to the space between the first counter magnet portions. When the magnetic field formed by the first counter magnet part is a first magnetic field and the magnetic field formed by the second counter magnet part is a second magnetic field,
The direction of the magnetic field is set so that the first magnetic field generates a force that separates the electrons from the space between the second opposing magnet parts,
2. The sputtering apparatus according to claim 1, wherein the direction of the magnetic field of the second magnetic field is set so as to generate a force for separating electrons from a space between the first opposing magnet portions.   4. The predetermined distance is a distance at which a magnetic field is not formed between a magnet constituting the first counter magnet part and a magnet constituting the second counter magnet part. The sputtering apparatus of any one of these.