JP2009129625A - Milling machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a milling machine reduced in errors of conveyance and sufficiently cooling a work piece when etching with ion beams. <P>SOLUTION: A load lock door 41 is externally provided on a vacuum chamber 20. An opening of the load lock door 41 is brought into tight abutment on a wall 20A defining the vacuum chamber 20 to seal the chamber to define a load lock chamber 40 by a part of the wall 20A and the load lock door 41. An aperture 20a is formed in the part of the wall 20A. The aperture 20a is formed through the wall 20A such that the vacuum chamber 20 communicates with the load lock chamber 40. A substrate holding end 60A is inserted into the aperture 20a to bring a brim 65 into tight abutment on the aperture 20a defining part of the wall 20A to isolate the vacuum chamber 20 from the load lock chamber 40. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a milling apparatus that performs an etching process by irradiating an ion beam.

  There is known a milling apparatus (also referred to as an ion beam etching apparatus) that performs an etching process by irradiating the surface of a workpiece such as a substrate with an ion beam. Such a milling apparatus has an ion source, a vacuum chamber, and a load lock chamber, and a substrate holder that supports a plurality of substrate holders on which a workpiece is placed in the vacuum chamber so as to be capable of revolving. A unit is provided and the ion source can irradiate the workpiece in the vacuum chamber with an ion beam.

The workpiece is mounted on a cassette in the load lock chamber, and the workpiece placed on the cassette after the load lock chamber is evacuated is transferred from the cassette to a holder in the vacuum chamber by a vacuum robot. Then, the substrate is placed on the substrate holder unit, and the workpiece is subjected to an etching process by being irradiated with an ion beam while being revolved. A milling device having such a configuration is described in, for example, Japanese Patent Application Laid-Open No. 2003-297275 (Patent Document 1).
JP 2003-297275 A

  Since the workpiece is irradiated with an ion beam and etched, the temperature of the workpiece itself rises. When the workpiece becomes high temperature, the workpiece is burned out. For this reason, in order to cool the workpiece placed on the holder, the portion of the substrate holder unit that supports the holder is provided with a cooling means such as a cooling channel for flowing cooling water for cooling the holder. Yes. Then, by placing the workpiece in close contact with the holder, the workpiece can be sufficiently cooled.

  However, in the above-described conventional milling apparatus, since the vacuum robot places the workpiece on the holder, it is difficult to reliably place the workpiece on the holder and place the workpiece on the holder. For this reason, there is a problem that the workpiece is burnt out without being sufficiently cooled. Another problem is that a transport error by the vacuum robot occurs.

  Therefore, an object of the present invention is to provide a milling apparatus that can sufficiently cool a workpiece during an etching process using an ion beam with few conveyance errors.

  In order to solve the above-described problems, the present invention provides a discharge vessel in which an opening is formed, a high-frequency coil provided outside the discharge vessel for generating plasma, and supplying high-frequency power to the high-frequency coil. An ion source comprising a high-frequency power source and an extraction electrode for extracting ions in the plasma generated in the discharge vessel out of the discharge vessel to generate an ion beam; and opening of the discharge vessel And a vacuum chamber communicating with the inside of the discharge vessel through the extraction electrode at the opening of the discharge vessel, and the vacuum chamber defined by a wall portion formed with the opening, and through the opening of the wall portion A load lock chamber that can communicate with the vacuum chamber, a workpiece holding unit main body having a workpiece holding surface for holding the workpiece, and an outer surface of the workpiece holding unit main body. A workpiece holding unit movable between a position facing the opening of the discharge vessel and a position of the opening of the wall in the vacuum chamber, and the load lock chamber An opening / closing door capable of switching between communication / blocking of air and the atmosphere, and the flange section divides the outer surface of the workpiece holding unit into one side having the workpiece holding surface and the other side. The work piece holding unit can be brought into intimate contact with the portion of the wall portion that defines the opening of the wall portion when the work piece holding unit is moved to the position of the opening of the wall portion, Is moved to the opening position of the wall portion, the opening portion of the wall portion is closed by the flange portion and the workpiece holding unit main body portion, and the workpiece holding surface takes the opening portion of the wall portion. A milling device that can be exposed to the load lock chamber side is provided.

  A workpiece having a load-lock chamber that is separated from the vacuum chamber by a wall portion having an opening and communicates with the vacuum chamber through the opening of the wall portion, and a workpiece holding surface for holding the workpiece. A holding unit main body and a flange provided on the outer surface of the workpiece holding unit main body, and a movable object that is movable between a position facing the opening of the discharge vessel and a position of the opening of the wall in the vacuum chamber. An open / close door that can switch between communication / blocking between the load lock chamber and the atmosphere, and the flange has a workpiece holding surface on the outer surface of the workpiece holding unit. The workpiece can be in close contact with the wall portion defining the wall opening when the workpiece holding unit is moved to the position of the wall opening. The holding unit body has moved to the open position on the wall. In addition, the opening of the wall is closed by the flange and the workpiece holding unit main body, and the workpiece holding surface can be exposed to the load lock chamber side through the opening of the wall. The workpiece holding surface can be exposed from the opening of the wall portion to the load lock chamber side in a state where the load lock chamber and the atmosphere are in communication. For this reason, it can be surely performed manually that the workpiece is held on the workpiece holding surface or the workpiece is removed. In other words, since the workpiece can be held or removed from the workpiece holding surface manually in the air instead of in a vacuum, the vacuum robot is used in the vacuum chamber as in the prior art. However, it is possible to prevent a conveyance error such that the workpiece cannot be held in a state where the workpiece is accurately adhered to the workpiece holding surface.

  In this way, the workpiece can be securely held in close contact with the workpiece holding surface, so that the workpiece held in close contact with the workpiece holding surface can be held in a sufficiently cooled workpiece. The surface can be sufficiently cooled, and the workpiece can be prevented from being heated and burned out during the etching process by the ion beam. In addition, since a vacuum robot is unnecessary, the cost for the vacuum robot can be reduced.

  In addition, since the workpiece holding surface can be exposed to the atmosphere while maintaining the vacuum state in the vacuum chamber, maintenance of the workpiece holding surface portion can be facilitated. Cleaning, replacement or maintenance of consumable members for holding the workpiece can be performed very easily, and productivity can be improved. Thus, milling processing such as etching processing using an ion beam can be repeatedly performed with high probability.

  Here, in the vacuum chamber, the workpiece holding unit is linearly movable between a position facing the opening of the discharge vessel and a position of the opening of the wall and parallel to the workpiece holding surface. It is preferable that the rotary shaft is supported so as to be rotatable about a rotating shaft.

  In the vacuum chamber, the workpiece holding unit is supported so as to be linearly movable between a position facing the opening of the discharge container and a position of the opening of the wall, and therefore, a position facing the opening of the discharge container The movement between the wall and the opening position can be performed within a shortest distance by linear movement. In addition, since it is supported so as to be rotatable about a rotation axis parallel to the workpiece holding surface, the workpiece holding surface can be easily opposed to the opening of the discharge vessel at a position facing the opening of the discharge vessel, The workpiece holding surface can be oriented in the direction of exposure from the opening of the wall portion to the load lock chamber side at the opening position of the wall portion.

  Further, when the workpiece holding unit is at least at a position facing the opening of the discharge vessel, a shutter disposed to face the opening of the wall portion and the portion of the wall portion in the vicinity of the opening in the vacuum chamber. It is preferable to be provided.

  When the workpiece holding unit is at least in a position facing the opening of the discharge vessel, a vacuum is provided in the vacuum chamber so as to face the opening of the wall portion and the wall portion in the vicinity of the opening. A portion of the chamber near the opening of the wall can be protected from the ion beam. In the vicinity of the opening of the wall portion, for example, a mechanism or a seal member is provided for bringing the collar portion into close contact with the portion in the vicinity of the opening of the wall portion in order to maintain a high vacuum in the vacuum chamber. These members can be prevented from being damaged by ion beam irradiation. For this reason, even when a large number of workpieces are repeatedly processed, the collar portion can be kept firmly fixed to the portion defining the opening of the wall portion, and the vacuum chamber can be reliably sealed. .

  Further, it has a substantially plate shape, and one surface can face the opening of the discharge vessel, penetrates from the one surface to the other surface facing the one surface, and is substantially the same as the workpiece holding surface. Comprising a protective plate having a through-hole formed in the shape, and when the workpiece holding unit is at a position facing the opening of the discharge vessel, the one surface faces the opening of the discharge vessel, The workpiece holding surface is exposed from the other surface side to the one surface side through the through hole of the protective plate, and the portion of the protective plate that defines the through hole is the flange portion and the flange portion. It is preferable to arrange at a position between the opening of the discharge vessel.

  A through-hole that has a substantially plate shape, one surface can be opposed to the opening of the discharge vessel, and penetrates from one surface to the other surface facing the one surface and has substantially the same shape as the workpiece holding surface When the workpiece holding unit is at a position facing the opening of the discharge vessel, one surface faces the opening of the discharge vessel, and the other side through the through hole of the protection plate The workpiece holding surface is exposed from the surface side to the one surface side, and the part of the protective plate that defines the through hole is disposed at a position between the collar part and the opening of the discharge vessel. Can be protected from the ion beam. For example, a seal member or the like is provided in the collar portion so as to be in close contact with the vicinity of the opening of the wall portion. To prevent the seal member from being damaged by the ion beam irradiation, for example. Can do. For this reason, even when a large number of workpieces are repeatedly processed, it is possible to keep the collar portion in close contact with the portion defining the opening of the wall portion via the sealing member, and to securely seal the vacuum chamber. Can continue.

  Moreover, it is preferable that the workpiece holding unit is provided with a cooling means for cooling the workpiece holding surface. Since the workpiece holding unit is provided with a cooling means for cooling the workpiece holding surface, it is possible to improve the cooling efficiency by fixing the workpiece to the workpiece holding surface. it can. For this reason, the temperature rise of workpieces, such as an element, by ion beam irradiation can be prevented, and the damage by a temperature rise can be prevented.

  Moreover, it is preferable that the workpiece holding surface is always oriented in the vertical direction. Since the workpiece holding surface is always oriented in the vertical direction, it is possible to make it difficult for particles generated by the etching process using the ion beam to the workpiece to adhere to the workpiece holding surface. For this reason, the process concerning the cleaning on the workpiece holding surface can be performed in a short time.

  As described above, the present invention can provide a milling apparatus that can sufficiently cool a workpiece during an etching process using an ion beam with few conveyance errors.

  A milling apparatus according to an embodiment of the present invention will be described with reference to FIGS. More specifically, the milling apparatus is an apparatus that etches a substrate which is a workpiece by an ion beam from an ion source. As the substrate, for example, a substrate such as a thin film magnetic head as described in JP-A-7-221081 can be cited, and a slider and the like of the thin film magnetic head are etched. The milling apparatus 1 has an ion source 10 that generates an ion beam, a vacuum chamber 20 that houses a substrate P (FIG. 4) irradiated with the ion beam, and a load lock chamber 40 that waits for the substrate P before processing. is doing. The vacuum chamber 20 is defined by the wall 20A.

A vacuum chamber first vacuum pump 21 and a vacuum chamber second vacuum pump 22 are provided outside the vacuum chamber 20, and these communicate with the inside of the vacuum chamber 20 through exhaust valves 23 and 23. By driving the vacuum chamber first vacuum pump 21 and the vacuum chamber second vacuum pump 22, the inside of the vacuum chamber 20 is brought to a vacuum state of about 10 ⁻⁴ Pa. Further, an electron neutralizer 24 for neutralizing an ion beam from an ion source 10 to be described later is installed outside the vacuum chamber 20. For example, when the ion beam is a positive ion such as Ar +, electrons are emitted from the electron neutralizer 24 and the space charge in the vacuum chamber 20 is neutralized.

  A load lock door 41 is provided outside the vacuum chamber 20. The load lock door 41 has a substantially rectangular parallelepiped shape, and an entire surface of the load lock door 41 forms an opening. One side that defines one surface forming the opening is supported by a wall portion 20A that defines the vacuum chamber 20 by a hinge, and the load lock door 41 is configured to be rotatable about the one side as a rotation axis. . An opening 41A of the load lock door 41 is provided with a seal member (not shown) and a bolt receiving portion (not shown). By rotating the load lock door 41, as shown in FIG. The opening 41A of the lock door 41 is brought into close contact with the wall 20A defining the vacuum chamber 20 and forming the left end shown in FIG. 1 via a seal member (not shown). Further, a bolt receiving portion (not shown) is fixed to the wall portion 20A and sealed with a bolt (not shown), whereby the load lock chamber 40 is defined by the portion of the wall portion 20A and the load lock door 41. Further, when the load lock door 41 is opened by rotating the load lock door 41, that is, as shown in FIG. 6, the opening 41 </ b> A of the load lock door 41 opens the vacuum chamber 20. The load lock door 41 corresponds to the load lock chamber 40 when the wall 20A is defined and is separated from the left end portion shown in FIG. The load lock door 41 corresponds to an opening / closing door.

A load lock first vacuum pump 42 and a load lock second vacuum pump 43 are provided outside the load lock door 41, and these communicate with the load lock chamber 40 via an exhaust valve 44. By driving the load lock first vacuum pump 42 and the load lock second vacuum pump 43 when the load lock chamber 40 is sealed as will be described later, the load lock chamber 40 has about 10 ⁻³ Pa level. The vacuum state.

  The ion source 10 includes a vacuum vessel having a substantially cylindrical shape (not shown), a discharge vessel having a substantially cylindrical shape, a coil that is provided outside the discharge vessel and generates plasma P in the discharge vessel, and a high frequency in the coil. A high-frequency power source to be described later for supplying electric power, and an extraction electrode for extracting ions in plasma generated in the discharge vessel from an opening 10a to be described later of the discharge vessel to generate an ion beam are provided.

  The discharge vessel is disposed coaxially with the vacuum vessel in the vacuum vessel. The discharge vessel is composed mainly of a dielectric material such as quartz or aluminum oxide, and is formed in a cylindrical shape having an opening 10a formed at one end in the axial direction. An opening is also formed at one end of the vacuum vessel, and an opening 10a of the discharge vessel is disposed in the vicinity of the opening of the vacuum vessel. The opening of the vacuum vessel is connected to a through hole formed in the wall portion 20A that defines the vacuum chamber 20, and the inside of the vacuum vessel communicates with the inside of the vacuum chamber 20 through the through hole. Is communicated with the inside of the vacuum chamber 20 via an extraction electrode 24 described later. The axial direction of the discharge vessel is relative to the workpiece holding surface 62 described later when the substrate cooling holder unit 60 is disposed at a position facing the opening 10a of the discharge vessel as shown in FIG. It is directed obliquely upward at an angle of approximately 45 °. In FIG. 10A, the upper part coincides with the vertical upper part, and the lower part coincides with the vertical lower part. At the other end in the axial direction of the discharge vessel, a supply port is formed to which a supply pipe for supplying gas from the gas supply device into the discharge vessel is connected.

  The coil is provided inside the vacuum vessel and outside the discharge vessel. The coil is provided so that its axis is located in the discharge vessel. A high frequency power source is connected to the coil via a high frequency matching device. The high frequency power source is, for example, a high frequency power source or a high frequency amplifier. The frequency of the high-frequency power source is several MHz to several tens of MHz (for example, 2 to 13.5 MHz), and is about 4 MHz in the present embodiment. The high frequency power source applies, for example, 200 to 2000 W of power to the coil according to the capacity and shape of the discharge vessel. With the above configuration, the high frequency power supply can supply predetermined high frequency power to the coil by the high frequency matching device.

  The extraction electrode has a screen grid, an acceleration grid, and a deceleration grid. The screen grid, the acceleration grid, and the deceleration grid are sequentially arranged from the inside to the outside of the discharge vessel. Each of the screen grid, the acceleration grid, and the deceleration grid is made of a metal plate in which a plurality of holes are formed.

  The screen grid separates the plasma and the acceleration grid. For example, a DC power source for continuously applying a high plasma voltage is connected to the screen grid. The voltage applied to the screen grid is, for example, 400 to 1500V. The voltage applied to the screen grid determines the ion beam energy of the ion beam.

  A DC power source for continuously applying a negative high voltage is connected to the acceleration grid. The voltage applied to the acceleration grid is, for example, −200 to −1000V. The deceleration grid is grounded. Ions extracted from the plasma in the discharge vessel are radiated out of the discharge vessel through holes formed in the screen grid, the acceleration grid, and the deceleration grid, respectively, and become an ion beam. The extraction electrode can control the ion beam diameter of the ion beam within a predetermined numerical range using the lens effect by adjusting the potential difference between the acceleration grid and the deceleration grid.

  An opening 20a is formed in the wall portion 20A defining the vacuum chamber 20 and forming the left end shown in FIG. The opening 20a is formed through the wall 20A so as to communicate the vacuum chamber 20 and the load lock chamber 40 in the state shown in FIG. The opening 20a has substantially the same shape as that of a substrate holding end 60A of the substrate cooling holder unit 60 described later, and the substrate holding end 60A can be inserted therein. As will be described later, the substrate holding end 60A is inserted, and a later-described flange portion 65 is brought into close contact with the portion of the wall portion 20A that defines the opening 20a, so that the inside of the vacuum chamber 20 and the load lock chamber 40 Is disconnected.

  A holder unit fixing mechanism 25 is provided in the vicinity of the opening 20a of the wall portion 20A defining the vacuum chamber 20 and forming the left end shown in FIG. The holder unit fixing mechanism 25 has six claw portions 25A arranged at a predetermined interval in the circumferential direction of the opening 20a. The claw portions 25A are flange portions of the substrate cooling holder unit 60 as will be described later. By pressing 65 against the portion of the wall portion 20A near the opening 20a, the flange portion 65 can be brought into close contact with the portion of the wall portion 20A near the opening 20a.

  Further, a shutter 26 is provided in the vicinity of the opening 20a of the wall portion 20A defining the vacuum chamber 20 and forming the left end shown in FIG. As shown in FIG. 5, the shutter 26 has two semicircular plate shapes, and when a substrate holding end 60A described later is not inserted into the opening 20a of the wall portion 20A, It can be circularly arranged in a circle and opposed to the opening 20a of the wall 20A and the portion of the wall 20A near the opening 20a. By being arranged so as to face each other, the opening 20a of the wall 20A is shielded, and the opening 20a of the wall 20A and the portion of the wall 20A that defines the opening 20a of the wall 20A are irradiated with an ion beam. Shield to prevent this.

  For this reason, there are a claw portion 25A of the holder unit fixing mechanism 25 provided in the vicinity of the opening 20a of the wall portion 20A, a seal surface formed by the portion of the wall portion 20A in the vicinity of the opening 20a and the flange portion 65 being pressed. It is possible to prevent damage caused by ion beam irradiation from the ion source 10. For this reason, even when a large number of workpieces P are repeatedly processed, the holder unit fixing mechanism 25 can keep the collar portion 65 closely fixed to the portion of the wall portion 20A in the vicinity of the opening 20a. Can be reliably sealed.

  A substrate cooling holder unit 60 is provided inside the vacuum chamber 20. The substrate cooling holder unit 60 is mounted on a rail (not shown), and the inside of the vacuum chamber 20 is opposed to the opening 10a of the discharge vessel of the ion source 10 as shown in FIG. As described above, the linear movement is possible between the position where the substrate holding end portion 60A is inserted into the opening 20a of the wall portion 20A.

  More specifically, as shown in FIG. 2, the substrate cooling holder unit 60 is not oriented in the vertical direction in FIG. 2, that is, in the vertical direction in FIG. The first rotation base 71 is supported so as to be rotatable about a single rotation axis, and the first rotation base 71 is rotatable about a second rotation axis that is spaced apart from the first rotation axis and is parallel to the first rotation axis. It is supported by the two-turn pedestal 72. A moving shield driving device 73 is provided on the rotating portion of the upper portion of the second rotating base 72. The moving shield driving device 73 moves the moving shield 74 in the axial direction of the main body 61 of the substrate cooling holder unit 60 described later. Supports movable. The movement shield 74 has a substantially plate shape having a pair of surfaces oriented in a direction perpendicular to the axial direction of the substrate cooling holder unit 60 described later, and a through hole 74a having substantially the same shape as the workpiece holding surface 62. Is formed so as to connect the pair of surfaces. When the etching process is performed by the ion beam, the substrate holding end portion 60A is inserted into the through hole 74a, and the flange portion 65 of the substrate cooling holder unit 60 described later is brought into contact with the moving shield 74. It is configured. The moving shield 74 corresponds to a protective plate.

  The second rotating pedestal 72 is placed on a rail (not shown), and one end of a bellows 75 is connected to the second rotating pedestal 72. The other end of the bellows 75 is connected to a wall portion 20 </ b> A that defines the vacuum chamber 20. When the second rotating pedestal 72 is driven, the second rotating pedestal 72, the first rotating pedestal 71, and the substrate cooling holder unit 60 are integrated with each other so as to face the opening 10a of the discharge vessel as shown in FIG. It is configured to move linearly between the position and a position where a later-described substrate holding end 60A is inserted into the opening 20a of the wall 20A as shown in FIG.

  The substrate cooling holder unit 60 has a main body portion 61 having a substantially cylindrical shape, and gas is prevented from passing through the inside of the main body portion 61, and one end surface in the axial direction of the main body portion 61 is formed on the workpiece P. Has a workpiece holding surface 62 for holding the workpiece. More specifically, one end surface of the main body 61 of the substrate cooling holder unit 60 forms a workpiece holding surface 62 having a substantially circular shape, and the workpiece holding surface 62 is in close contact with the workpiece P. It comprises a holding surface 63A, which will be described later, which is the surface of a substantially circular cooling plate 63 (FIG. 4) in contact, and a shield cover 64. As shown in FIG. 3, three cooling plates 63 are provided at equal intervals in the circumferential direction of the workpiece holding surface 62 at positions near the periphery of the workpiece holding surface 62. The main body 61 corresponds to a workpiece holding unit main body, and the substrate cooling holder unit 60 corresponds to a workpiece holding unit.

  The cooling plate 63 has a holding surface 63A provided with a clamp 63B for holding the workpiece P, and the holding surface 63A is perpendicular to the rotation axis of the cooling plate 63 described later. A cooling water passage (not shown) for flowing cooling water is formed in the cooling plate 63 and in the vicinity of the holding surface 63A.

  The workpiece holding surface 62 can rotate around the axis of the main body 61 of the substrate cooling holder unit 60, and the cooling plate 63 rotates around its center as a rotation axis and rotates the workpiece holding surface 62. Revolve around the axis. More specifically, as shown in FIGS. 3 and 4, the substrate cooling holder unit 60 includes a gear 81 provided so as not to rotate with respect to the main body 61 of the substrate cooling holder unit 60, and the substrate cooling holder. A motor 82 (FIG. 4) fixed to the main body 61 of the unit 60 is included. The output shaft of the motor 82 extends upward in FIG. 4 through a coupling 82B and a vacuum rotary seal 82C, and a gear 82A is rotatably provided integrally with the output shaft at the upper end thereof. And an internal gear 83 arranged coaxially with each other.

  The internal gear 83 is provided in the vicinity of the peripheral edge along the peripheral edge of the rotary plate 83A having a substantially disk shape provided substantially coaxially with the gear 81, and at the upper end of the rotary plate 83A shown in FIG. A rotary joint 83B having a substantially cylindrical shape for rotatably supporting the rotation shaft of the cooling plate 63 is fixed to the rotation plate 83A. The rotation axis of the cooling plate 63 is arranged at the axial center position of the rotary joint 83B and penetrates the rotary joint 83B. A gear 63C is provided at the lower end of the rotating shaft of the cooling plate 63 shown in FIG. 4 so as to be able to rotate integrally with the rotating shaft, and the gear 63C is provided on a gear 84 provided so as to revolve around the axis of the gear 81. Meshed.

  When the motor 82 is driven, the gear 82A rotates, and the internal gear 83 rotates integrally with the rotary plate 83A and the rotary joint 83B. Then, the cooling plate 63 supported by the rotary joint 83B revolves around the rotation axis of the rotation plate 83A. At this time, since the gear 81 cannot rotate with respect to the main body 61 of the substrate cooling holder unit 60, the gear 84 meshing with the gear 81 and the gear 63C meshing with the gear 84 rotate to rotate the cooling plate 63 ( (Rotation).

  The gear 81 is fixed to the outer periphery of a substantially cylindrical rotary joint 81A. Therefore, the rotary joint 81 </ b> A cannot rotate with respect to the main body 61 of the substrate cooling holder unit 60 like the gear 81. A main shaft 64A is disposed at the axial center position of the gear 81 and the rotary joint 81A. The main shaft 64A is configured to be rotatable with respect to the gear 81 and the rotary joint 81A, and is connected to the rotary plate 83A via a connecting member. Therefore, the main shaft 64A and the rotating plate 83A are configured to be integrally rotatable.

  Two cooling water passages (not shown) extending in the vertical direction of FIG. 4 are formed inside the main shaft 64A. The cooling water flow path (not shown) is connected to the cooling water tubes 64B and 64B at the upper end of the main shaft 64A in FIG. 4, and the cooling tubes 64B and 64B are connected to the inlet and the outlet of the cooling water flow path of the cooling plate 63, respectively. Yes. The cooling water flow path (not shown) is connected to the cooling tubes 64C and 64C via a so-called rotary joint (not shown) at the lower end of the main shaft 64A. One cooling tube 64C passes through the rotary joint 81A and is connected to a cooling water supply device (not shown), and the other cooling tube 64C passes through the rotary joint 81A and is connected to a cooling water drain device (not shown).

  As shown in FIG. 2, the workpiece is held on the peripheral surface of the main body 61 of the substrate cooling holder unit 60 having a substantially cylindrical shape and serving as one end surface in the axial direction of the main body 61 of the substrate cooling holder unit 60. A flange 65 extending from the peripheral surface to the outer side in the radial direction of the main body 61 of the substrate cooling holder unit 60 is provided at a portion spaced from the surface 62 by the predetermined distance. A portion of the substrate cooling holder unit 60 on the one end surface side in the axial direction of the main body portion 61 with respect to the flange portion 65 forms a substrate holding end portion 60A. A sealing member (not shown) is provided along the peripheral surface of the main body 61 of the substrate cooling holder unit 60 on the substrate holding end 60A side of the flange 65, and as will be described later, the flange 65 and the vacuum chamber 20 are provided. The wall portion 20A that defines the opening 20a is in close contact with the portion of the wall portion 20A via a seal member (not shown).

When performing an etching process using an ion beam in the milling apparatus 1, first, as shown in FIG. 6, the substrate holding end portion of the substrate cooling holder unit 60 is formed in the opening 20a of the wall portion 20A defining the vacuum chamber 20. 60A is inserted to close the opening 20a of the wall 20A, and the workpiece holding surface 62 is exposed from the opening 20a of the wall 20A to the load lock chamber 40 side. Then, the flange portion 65 of the substrate cooling holder unit 60 is pressed by the plurality of claw portions 25A of the holder unit fixing mechanism 25 against the portion of the wall portion 20A in the vicinity of the opening 20a through a seal member (not shown) of the flange portion 65. Make close contact with. As a result, the vacuum chamber 20 is sealed. Next, using the vacuum chamber first vacuum pump 21 (FIG. 1) and the vacuum chamber second vacuum pump 22, the vacuum chamber 20 is evacuated to about 10 ⁻⁴ Pa.

Next, as shown in FIG. 6, the load lock door 41 is opened, and the substrate, which is the workpiece P, is held in close contact with the cooling plate 63 (FIG. 4) by hand. Next, as shown in FIG. 7, the load lock door 41 is closed and communication between the load lock chamber 40 and the atmosphere is cut off. Next, by operating a switch (not shown), the drive of the load lock first vacuum pump 42 (FIG. 1) and the load lock second vacuum pump 43 is started, and the load lock chamber 40 is about 10 ⁻³ Pa level. Set to vacuum.

  Next, the collar portion 65 of the substrate cooling holder unit 60 is released by the plurality of claw portions 25A of the holder unit fixing mechanism 25, and the second rotary base 72 is driven as shown in FIGS. The substrate cooling holder unit 60 is linearly moved along the rail on a rail (not shown) and moved to a position facing the opening 10a of the discharge vessel as shown in FIG. During this movement, the moving shield 74 is moved in the axial direction of the substrate cooling holder unit 60, and the substrate holding end 60A is inserted into the through hole 74a of the moving shield 74 as shown in FIGS. The workpiece holding surface 62 is exposed from the other surface side of the moving shield 74 to the one surface side through the through hole 74 a of the moving shield 74, and the flange portion 65 of the substrate cooling holder unit 60 contacts the moving shield 74. Keep in contact.

  Further, during this movement, as shown in FIG. 8, the shutter 26 is moved to face the opening 20a of the wall 20A and the portion of the wall 20A in the vicinity of the opening 20a, and the opening 20a of the wall 20A. Are shielded so as to prevent the ion beam from being irradiated to the opening 20a of the wall 20A and the portion of the wall 20A that defines the opening 20a of the wall 20A. Further, during this movement, the substrate cooling holder unit 60 is rotated 180 ° by the first rotating pedestal 71 to change from the state shown in FIG. 7A to the state shown in FIG. 8A, and further to the second rotating pedestal 72. Thus, the substrate cooling holder unit 60, the moving shield 74, the moving shield driving device 73, and the first rotating base 71 are rotated by 45 ° from the state shown in FIG. 9B to the state shown in FIG. 10B. . For convenience of drawing, the substrate cooling holder unit 60, the moving shield 74, the moving shield driving device 73, and the first rotating base 71 in FIG. 10A are drawn in the same posture as in FIG. 9A. Actually, the posture is opposed to the opening 10a of the discharge vessel so as to correspond to FIG.

  Next, an electron beam is emitted from the electron neutralizer 24 and an ion beam is emitted from the ion source 10 to the substrate which is the workpiece P, thereby performing an etching process. During the etching process, the motor 82 is driven, and the cooling plate 63 revolves around the main shaft 64A while rotating around the rotation axis of the cooling plate 63.

  Next, by driving the second rotating base 72, the substrate cooling holder unit 60 is linearly moved along the rail on a rail (not shown), and from a position facing the opening 10a of the discharge vessel as shown in FIG. 6, the substrate holding end portion 60A of the substrate cooling holder unit 60 is inserted into the opening 20a of the wall portion 20A that defines the vacuum chamber 20. During this movement, the moving shield 74 is moved away from the substrate cooling holder unit 60 in the axial direction of the substrate cooling holder unit 60, and as shown in FIGS. Then, the substrate holding end portion 60A is detached.

  Further, during this movement, as shown in FIG. 6, the shutter 26 is moved and arranged at a position not facing the opening 20a of the wall 20A and the portion of the wall 20A in the vicinity of the opening 20a. Further, during the movement, the substrate cooling holder unit 60, the moving shield 74, the moving shield driving device 73, and the first rotating base 71 are rotated by 45 ° by the second rotating base 72 from the state shown in FIG. The state shown in FIG. 9B is set, and the substrate cooling holder unit 60 is further rotated by 180 ° by the first rotary base 71 to change from the state shown in FIG. 8A to the state shown in FIG. .

  Next, the flange portion 65 of the substrate cooling holder unit 60 is pressed against the portion of the wall portion 20A in the vicinity of the opening 20a through the seal member of the flange portion 65 by the plurality of claw portions 25A of the holder unit fixing mechanism 25. The portion 65 is brought into close contact with the portion of the wall portion 20A in the vicinity of the opening 20a through the sealing member of the flange portion 65. As a result, the vacuum chamber 20 is sealed. Next, the load lock chamber 40 is vented to atmospheric pressure, and then the load lock door 41 is opened. Then, the substrate which is the workpiece P is manually removed from the cooling plate 63, and the substrate to be processed next is held on the cooling plate 63. By repeatedly performing the above steps, etching processing by an ion beam is continuously performed.

As shown in FIG. 6, after the substrate holding end 60 </ b> A of the substrate cooling holder unit 60 is inserted into the opening 20 a of the wall 20 </ b> A defining the vacuum chamber 20 and the vacuum chamber 20 is sealed, the load lock chamber The inside of 40 is vented to atmospheric pressure, the substrate is taken in and out, the inside of the load lock chamber 40 is brought to a vacuum state of about 10 ⁻³ Pa in the next etching process, and a plurality of holder unit fixing mechanisms 25 are arranged. The claw portion 25A of the substrate cooling holder unit 60 is released by the claw portion 25A, and the substrate holding end portion 60A of the substrate cooling holder unit 60 is not inserted into the opening 20a of the wall portion 20A that defines the vacuum chamber 20. In the meantime, the vacuum chamber 20 is maintained in a vacuum state of about 10 ⁻⁴ Pa. In the load lock chamber, when a workpiece such as a substrate is not attached to the substrate cooling holder unit 60 and is waiting for processing, the load lock door is closed, and the load lock chamber is filled with nitrogen or other materials. It is maintained at atmospheric pressure with an inert gas or dry air.

  As described above, the workpiece holding surface 62 can be exposed to the load lock chamber 40 side from the opening 20a of the wall portion 20A, with the load lock door 41 communicating the inside of the load lock chamber 40 and the atmosphere. For this reason, it is possible to reliably manually hold the workpiece P with respect to the workpiece holding surface 62 or remove the workpiece P manually. That is, the work P can be held or removed from the work holding surface 62 manually in the air instead of in the vacuum, so that the work P can be removed from the inside of the vacuum chamber as in the prior art. In this case, it is possible to prevent a transport error such that the vacuum robot cannot be held in a state in which the workpiece is accurately brought into close contact with the workpiece holding surface.

  Since the workpiece P can be securely held in close contact with the workpiece holding surface 62, the workpiece P held in close contact with the workpiece holding surface 62 is held by the sufficiently cooled holding surface 63A. It is possible to sufficiently cool, and to prevent the workpiece P from becoming high temperature and being burned out during the etching process by the ion beam. In addition, since a vacuum robot is unnecessary, the cost for the vacuum robot can be reduced.

  In addition, since the workpiece holding surface 62 can be exposed to the atmosphere while the vacuum state in the vacuum chamber 20 is maintained, maintenance of the portion of the workpiece holding surface 62 can be facilitated. Cleaning of the object holding surface 62 (removal of particles), replacement and maintenance of consumable members such as the clamp 63B for holding the shield cover 64 and the workpiece P, etc. can be performed very easily, improving productivity. Can be made. Thus, milling processing such as etching processing using an ion beam can be repeatedly performed with high probability.

  In a milling apparatus in which the workpiece holding surface is always oriented in the horizontal direction, particles generated by the etching process using the ion beam are likely to adhere to the workpiece holding surface. This is because, in a milling apparatus in which the workpiece holding surface is always oriented in the horizontal direction, the generated particles are placed on the workpiece holding surface as they are. However, in the present embodiment, since the workpiece holding surface 62 is always oriented in the vertical direction, the particles are unlikely to adhere to the workpiece holding surface 62, and the workpiece P is put in and out. In addition, since the workpiece holding surface 62 can be cleaned, the cycle of releasing the milling device 1 and cleaning the inside thereof can be significantly lengthened. The cleaning cycle of the milling device 1 is mainly due to contamination inside the ion source 10 and contamination of the extraction electrode. In the present embodiment, when viewed in terms of the number of substrates to be processed P, a cleaning cycle of about once is required for approximately three times the number of conventional milling apparatuses.

  Further, since the substrate cooling holder unit 60 is supported in the vacuum chamber 20 so as to be linearly movable, the substrate cooling holder unit 60 moves between a position facing the opening 10a of the discharge vessel of the ion source 10 and a position of the opening 20a of the wall portion 20A. Can be performed at the shortest distance by linear movement. Further, since it is supported so as to be rotatable about a rotation axis parallel to the workpiece holding surface 62, the rotation about the rotation axis parallel to the workpiece holding surface 62 causes rotation to the opening 10a of the discharge vessel. The workpiece holding surface 62 is easily made to face the opening 10a of the discharge vessel at the facing position, or the workpiece holding surface 62 from the opening 20a of the wall portion 20A to the load lock chamber 40 side at the opening 20a position of the wall portion 20A. Can be easily oriented and exposed.

  Further, since the shutter 26 is provided, the portion in the vacuum chamber 20 near the opening 10a of the wall portion 20A can be protected from the ion beam. For this reason, it is possible to prevent the claw portion 25A of the holder unit fixing mechanism 25 provided in the vicinity of the opening 10a of the wall portion 20A, the seal member (not shown), and the like from being damaged by the ion beam irradiation. For this reason, even when a large number of workpieces P are repeatedly processed, the flange portion 65 can be kept tightly fixed to the portion defining the opening 10a of the wall portion 20A, and the vacuum chamber 20 can be reliably sealed. Can continue.

  Moreover, since the movement shield 74 is provided, the part of the collar part 65 can be protected from an ion beam. The flange portion 65 is provided with a seal member that is brought into close contact with the vicinity of the opening 20a of the wall portion 20A. This seal member is prevented from being damaged by ion beam irradiation. be able to. For this reason, even when a large number of workpieces P are repeatedly processed, the flange portion 65 can be kept in close contact with the portion defining the opening 20a of the wall portion 20A via the seal member, and the vacuum chamber 20 can be reliably sealed.

  In addition, since the substrate cooling holder unit 60 has a cooling channel for cooling the holding surface 63A, the work efficiency can be improved by closely fixing the workpiece P to the holding surface 63A. it can. For this reason, the temperature rise of the workpiece P such as a substrate or an element can be prevented by ion beam irradiation, and damage due to the temperature rise can be prevented.

  The milling device according to the present invention is not limited to the above-described embodiments, and various modifications and improvements can be made within the scope described in the claims. For example, the shape of the vacuum chamber and the shape of the load lock chamber are not limited to the shape of the vacuum chamber and the shape of the load lock chamber in the present embodiment.

  The present invention can be used in the field of milling apparatuses that perform an etching process by irradiating an ion beam.

The upper view explanatory drawing which shows the milling apparatus by embodiment of this invention. Side view explanatory drawing which shows the milling apparatus by embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Front view explanatory drawing which shows the structure which revolves the cooling plate of the milling apparatus by embodiment of this invention. Side view explanatory drawing which shows the structure which revolves the cooling plate of the milling apparatus by embodiment of this invention. It is explanatory drawing which looked at the milling device by an embodiment of the invention from the load lock room side, (a) is a figure showing a position of a load lock door when a load lock door is closed, and (b) is a load lock door. The figure which shows the state which opened. It is explanatory drawing which shows the time of mounting | wearing of the workpiece in the milling apparatus by embodiment of this invention, (a) is explanatory drawing of side view, (b) is explanatory drawing of planar view. It is explanatory drawing which shows the state which the board | substrate cooling holder unit is linearly moving in the milling apparatus by embodiment of this invention, (a) is explanatory drawing of side view, (b) is explanatory drawing of planar view. It is explanatory drawing which shows a mode that the shutter has blocked the opening of the wall part in the milling apparatus by embodiment of this invention, (a) is explanatory drawing of side view, (b) is explanatory drawing of planar view. It is explanatory drawing which shows the state which the board | substrate cooling holder unit is linearly moving in the milling apparatus by embodiment of this invention, (a) is explanatory drawing of side view, (b) is explanatory drawing of planar view. It is explanatory drawing which shows the state by which the substrate cooling holder unit was arrange | positioned in the position facing the opening of a discharge vessel in the milling apparatus by embodiment of this invention, (a) is explanatory drawing of side view, (b) is Explanatory drawing of planar view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Milling apparatus 10 Ion source 10a Opening 20 Vacuum chamber 20A Wall part 25A Edge part 26 Shutter 40 Load lock chamber 41 Load lock door 42 2nd rotation base 60 Substrate cooling holder unit 61 Main-body part 62 Workpiece holding surface 64B, 64C Cooling Tube 71 First rotating base 74 Movement shield 74a Through hole P Workpiece

Claims (6)

A discharge vessel having an opening formed therein, a high-frequency coil provided outside the discharge vessel for generating plasma in the discharge vessel, a high-frequency power source for supplying high-frequency power to the high-frequency coil, and the generated in the discharge vessel An ion source comprising an extraction electrode for extracting ions in plasma from the opening of the discharge vessel to the outside of the discharge vessel to generate an ion beam;
A vacuum chamber connected to the opening of the discharge vessel and communicating with the inside of the discharge vessel through the extraction electrode at the opening of the discharge vessel;
A load lock chamber that is partitioned from the vacuum chamber by a wall portion having an opening, and is capable of communicating with the vacuum chamber through the opening of the wall portion;
A discharge container in the vacuum chamber, comprising: a workpiece holding unit main body having a workpiece holding surface for holding the workpiece; and a flange provided on an outer surface of the workpiece holding unit main body. A workpiece holding unit that is movable between a position facing the opening and a position of the opening in the wall,
An open / close door capable of switching communication / blocking between the load lock chamber and the atmosphere;
The flange portion divides the outer surface of the workpiece holding unit into one side having the workpiece holding surface and the other side, and the workpiece holding unit moves to the position of the opening of the wall portion. And can be in close contact with the portion of the wall that defines the opening of the wall,
When the workpiece holding unit main body moves to the opening position of the wall, the flange and the workpiece holding unit main body close the opening of the wall and the workpiece holding surface. Can be exposed to the load-lock chamber through the opening of the wall.   In the vacuum chamber, the workpiece holding unit has a rotational axis that is linearly movable between a position facing the opening of the discharge vessel and a position of the opening of the wall and parallel to the workpiece holding surface. The milling device according to claim 1, wherein the milling device is supported so as to be rotatable about the center.   When the workpiece holding unit is at least at a position facing the opening of the discharge vessel, a shutter is provided in the vacuum chamber so as to face the opening of the wall and the portion of the wall near the opening. The milling device according to claim 1, wherein the milling device is provided. It has a substantially plate shape, and one surface can face the opening of the discharge vessel, penetrates from the one surface to the other surface facing the one surface, and has substantially the same shape as the workpiece holding surface. Comprising a protective plate with through-holes formed,
When the workpiece holding unit is in a position facing the opening of the discharge vessel, the one surface faces the opening of the discharge vessel, and the other surface side through the through hole of the protective plate The workpiece holding surface is exposed from the one surface side to the one surface side, and the portion of the protective plate that defines the through hole is disposed between the flange portion and the opening of the discharge vessel. The milling device according to any one of claims 1 to 3, characterized in that:   The milling device according to any one of claims 1 to 4, wherein the workpiece holding unit is provided with a cooling means for cooling the workpiece holding surface.   The milling device according to any one of claims 1 to 5, wherein the workpiece holding surface is always oriented in a vertical direction.

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