JP2019032940A - Ion implanter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve long-term reliability of a wafer inspection process in an injection processing chamber. An ion implantation apparatus 10 is a beamline apparatus that provides an injection processing chamber 16 for irradiating a wafer W with an ion beam and an ion beam B traveling in the injection processing chamber 16 along a predetermined beam trajectory. 14 and an inspection device 60 that optically inspects the wafer W via an optical member having an exposed surface that can be exposed in the implantation processing chamber 16, and because it can be arranged on the beam orbit in the implantation processing chamber 16. It is provided with a shielding member provided at a position between a beam collision portion that can be a source of pollutants due to an ion beam collision and an exposed surface of an optical member and at a position avoiding the optical axis of the inspection device 60. .. [Selection diagram] Fig. 3

Description

  The present invention relates to an ion implantation apparatus.

  In the semiconductor manufacturing process, an “ion implantation process” is performed in which an ion beam is irradiated onto a substrate (semiconductor wafer) held on a holder (platen) provided in a vacuum vessel. For the purpose of improving the accuracy of such ion implantation processing, an inspection device is used that detects the position and rotation angle of the wafer in the vacuum vessel by imaging with an imaging device and performing image processing. The inspection apparatus is provided outside the vacuum container, for example, and images the wafer in the vacuum container through a window plate provided on the ceiling of the vacuum container (see Patent Document 1).

JP 2010-92619 A

  Dirt adheres to the inner wall of a vacuum vessel (also referred to as an implantation processing chamber) in which ion implantation processing is performed as the apparatus is operated. As a result, dirt also adheres to the window plate for the inspection apparatus, and there is a possibility that the inspection accuracy deteriorates due to the dirt of the window plate and the reliability of the wafer inspection process is lowered. In order to maintain the inspection accuracy, maintenance such as periodically removing dirt on the window plate or replacing the window plate itself occurs. Since the apparatus cannot be used during maintenance, it is preferable to minimize the maintenance frequency from the viewpoint of improving the throughput of the apparatus.

  The present invention has been made in view of such circumstances, and one of its purposes is to provide a technique for improving the long-term reliability of a wafer inspection process in an implantation processing chamber.

  An ion implantation apparatus according to an aspect of the present invention includes an implantation processing chamber in which an ion beam is irradiated onto a wafer, a beam line device that provides an ion beam that travels along a predetermined beam trajectory in the implantation processing chamber, and an implantation processing. An inspection device that optically inspects the wafer through an optical member having an exposed surface that can be exposed to the room, and a beam source in the implantation processing chamber, which can be disposed on the beam trajectory, and thus becomes a source of contaminants due to the collision of the ion beam. And a shielding member provided at a position between the possible beam collision location and the exposed surface of the optical member and avoiding the optical axis of the inspection apparatus.

  Note that any combination of the above-described constituent elements and the constituent elements and expressions of the present invention replaced with each other among methods, apparatuses, systems, etc. are also effective as an aspect of the present invention.

  According to the present invention, the long-term reliability of the wafer inspection process in the implantation processing chamber can be improved.

It is a top view which shows schematic structure of the ion implantation apparatus which concerns on embodiment. It is a side view which shows schematic structure of the ion implantation apparatus in implantation processing. It is a side view which shows schematic structure of the ion implantation apparatus during a wafer test | inspection. It is a side view which shows typically the beam collision location in an injection processing chamber. FIGS. 5A to 5F are cross-sectional views schematically showing the configuration of the imaging shielding member. It is a side view which shows schematic structure of the injection processing chamber which concerns on a modification. It is a side view which shows schematic structure of the injection processing chamber which concerns on another modification. It is a side view which shows schematic structure of the injection processing chamber which concerns on another modification.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate. Moreover, the structure described below is an illustration and does not limit the scope of the present invention at all.

  FIG. 1 is a top view schematically showing an ion implantation apparatus 10 according to an embodiment. 2 and 3 are side views showing a schematic configuration of the ion implantation apparatus 10. Although details will be described later, FIG. 2 schematically shows a state during the implantation process, and FIG. 3 schematically shows a state during the wafer inspection.

  The ion implantation apparatus 10 is configured to perform ion implantation processing on the surface of the workpiece W. The workpiece W is, for example, a substrate, for example, a semiconductor wafer. Therefore, in the following description, the workpiece W may be referred to as a wafer W for convenience of explanation, but this is not intended to limit the target of the implantation process to a specific object.

  The ion implantation apparatus 10 is configured to irradiate the ion beam B over the entire processing surface of the wafer W by reciprocating the beam in one direction and reciprocating the wafer W in a direction perpendicular to the scanning direction. In this document, for convenience of explanation, the traveling direction of the ion beam B traveling on the designed beam trajectory is defined as the z direction, and the plane perpendicular to the z direction is defined as the xy plane. When scanning the workpiece W with the ion beam B, the beam scanning direction is the x direction, and the z direction and the direction perpendicular to the x direction are the y direction. Therefore, the reciprocating scanning of the beam is performed in the x direction, and the reciprocating motion of the wafer W is performed in the y direction.

  The ion implantation apparatus 10 includes an ion source 12, a beam line device 14, an implantation processing chamber 16, and a wafer transfer device 18. The ion source 12 is configured to provide an ion beam B to the beam line device 14. The beam line device 14 is configured to transport ions from the ion source 12 to the implantation processing chamber 16. The wafer transfer device 18 is configured to carry an unprocessed wafer to be implanted into the implantation processing chamber 16 and to carry out the treated wafer subjected to the implantation processing from the implantation processing chamber 16. In addition, the ion implantation apparatus 10 includes a vacuum exhaust system (not shown) for providing a desired vacuum environment to the ion source 12, the beam line device 14, the implantation processing chamber 16, and the wafer transfer device 18.

  The beam line device 14 includes, for example, sequentially from the upstream, the mass analysis unit 20, the variable aperture 21, the beam shaping unit 22, the first beam measuring device 24, the beam scanner 26, the collimating lens 30, or the beam collimating device, and An angular energy filter (AEF) 34 is provided. Note that the upstream side of the beam line device 14 indicates the side close to the ion source 12, and the downstream side indicates the side close to the implantation processing chamber 16 (or the beam stopper 38).

  The mass analyzer 20 is provided downstream of the ion source 12 and is configured to select necessary ion species from the ion beam B extracted from the ion source 12 by mass analysis.

  The variable aperture 21 is an aperture whose aperture width can be adjusted, and adjusts the beam current amount of the ion beam B passing through the aperture by changing the aperture width. The variable aperture 21 may include, for example, an aperture plate that is disposed above and below the beam line, and may adjust the beam current amount by changing the interval between the aperture plates.

  The beam shaping unit 22 includes a converging / diverging lens such as a quadrupole focusing / diverging device (Q lens), and is configured to shape the ion beam B that has passed through the variable aperture 21 into a desired cross-sectional shape. . The beam shaping unit 22 is an electric field type three-stage quadrupole lens (also referred to as a triplet Q lens), and includes three quadrupole lenses. The beam shaping unit 22 can independently adjust the convergence or divergence of the ion beam B incident on the wafer W in the x and y directions in each direction by using three lens devices. The beam shaping unit 22 may include a magnetic lens device, or may include a lens device that shapes a beam using both an electric field and a magnetic field.

  The first beam measuring device 24 is an injector flag Faraday cup that is arranged so as to be able to be put in and out of the beam line and measures the current of the ion beam. The first beam measuring device 24 is configured to measure the beam current of the ion beam B shaped by the beam shaping unit 22. The first beam measuring instrument 24 includes a Faraday cup 24b that measures a beam current and a drive unit 24a that moves the Faraday cup 24b up and down. As shown by the broken line in FIG. 2, when the Faraday cup 24b is arranged on the beam line, the ion beam B is blocked by the Faraday cup 24b. On the other hand, as shown by the solid line in FIG. 2, when the Faraday cup 24b is removed from the beam line, the blocking of the ion beam B is released.

  The beam scanner 26 is configured to provide reciprocal scanning of the beam, and is a deflecting unit that scans the shaped ion beam B in the x direction. The beam scanner 26 has a pair of scanning electrodes 28 provided to face each other in the x direction. The scan electrode pair 28 is connected to a variable voltage power source (not shown). By periodically changing the voltage applied to the scan electrode pair 28, the electric field generated between the electrodes is changed to change the ion beam B. Deflection to various angles. Thus, the ion beam B is scanned over the scanning range in the x direction. In FIG. 1, the arrow X indicates the beam scanning direction and scanning range, and a plurality of trajectories of the ion beam B in the scanning range are indicated by alternate long and short dash lines.

  The collimating lens 30 is configured so that the traveling direction of the scanned ion beam B is parallel to the designed beam trajectory. The collimating lens 30 has a plurality of arc-shaped P lens electrodes 32 each having an ion beam passage slit at the center. The P lens electrode 32 is connected to a high voltage power source (not shown), and an electric field generated by voltage application is applied to the ion beam B so that the traveling directions of the ion beam B are aligned in parallel. The collimating lens 30 may be replaced with another beam collimating device, and the beam collimating device may be configured as a magnet device using a magnetic field. An AD (Accel / Decel) column (not shown) for accelerating or decelerating the ion beam B may be provided downstream of the collimating lens 30.

  The angular energy filter (AEF) 34 is configured to analyze the energy of the ion beam B and deflect ions having a required energy downward to guide the ions to the implantation processing chamber 16. The angular energy filter 34 has an AEF electrode pair 36 for electric field deflection. The AEF electrode pair 36 is connected to a high voltage power source (not shown). In FIG. 2, the ion beam B is deflected downward by applying a positive voltage to the upper AEF electrode and a negative voltage to the lower AEF electrode. The angular energy filter 34 may be configured by a magnetic device for magnetic field deflection, or may be configured by a combination of an AEF electrode pair for electric field deflection and a magnet device.

  In this way, the beam line device 14 supplies the ion beam B to be irradiated to the wafer W to the implantation processing chamber 16.

  As shown in FIG. 2, the implantation processing chamber 16 includes a platen driving device 50 that holds one or a plurality of wafers W. The platen driving device 50 includes a wafer holding device 52, a reciprocating motion mechanism 54, a twist angle adjusting mechanism 56, and a tilt angle adjusting mechanism 58. Wafer holding device 52 includes an electrostatic chuck or the like for holding wafer W. The reciprocating mechanism 54 reciprocates the wafer held by the wafer holding device 52 in the y direction by reciprocating the wafer holding device 52 in the reciprocating motion direction (y direction) orthogonal to the beam scanning direction (x direction). Let In FIG. 2, the reciprocating motion of the wafer W is illustrated by the arrow Y.

  The twist angle adjusting mechanism 56 is a mechanism for adjusting the rotation angle of the wafer W, and by rotating the wafer W around the normal line of the wafer processing surface, the alignment mark provided on the outer peripheral portion of the wafer and the reference position are aligned. Adjust the twist angle between. Here, the wafer alignment mark refers to a notch or orientation flat provided on the outer peripheral portion of the wafer, and refers to a mark serving as a reference for the angular position in the crystal axis direction of the wafer or in the circumferential direction of the wafer. The twist angle adjusting mechanism 56 is provided between the wafer holding device 52 and the reciprocating mechanism 54 and is reciprocated together with the wafer holding device 52.

  The tilt angle adjustment mechanism 58 is a mechanism for adjusting the tilt of the wafer W, and adjusts the tilt angle between the traveling direction of the ion beam B toward the wafer processing surface and the normal line of the wafer processing surface. In the present embodiment, among the tilt angles of the wafer W, an angle with the x-direction axis as the rotation center axis is adjusted as the tilt angle. The tilt angle adjusting mechanism 58 is provided between the reciprocating mechanism 54 and the wall surface of the implantation processing chamber 16, and the tilt angle of the wafer W is rotated by rotating the entire platen driving device 50 including the reciprocating mechanism 54 in the R direction. Configured to adjust.

  The platen driving device 50 holds the wafer W so that the wafer W can move between an implantation position where the ion beam B is irradiated onto the wafer W and an inspection position where the inspection device 60 inspects the wafer W. . FIG. 2 shows a state in which the wafer W is at the implantation position, and the platen driving device 50 holds the wafer W so that the trajectory of the ion beam B and the wafer W intersect each other. FIG. 3 shows a state in which the wafer W is at the inspection position, and the wafer W is held so that the optical axes C1 and C2 of the inspection apparatus 60 and the wafer W intersect each other. The platen driving device 50 moves the wafer W between the implantation position and the inspection position mainly by combining the rotational movement in the R direction by the tilt angle adjusting mechanism 58 and the linear movement in the Y direction by the reciprocating movement mechanism 54. Let

  In the present embodiment, the inspection position of the wafer W shown in FIG. 3 is common to the loading / unloading position for loading or unloading the wafer W with the wafer transfer device 18. At the inspection position or the loading / unloading position, the wafer W is arranged in such a direction that the wafer processing surface is in the horizontal direction. The inspection position of the wafer W may be different from the loading / unloading position of the wafer W. The loading / unloading position of the wafer W corresponds to the position of the wafer holding device 52 when the wafer W is loaded or unloaded through the loading / unloading port 80 by the transfer mechanism or transfer robot provided in the wafer transfer device 18.

  The implantation processing chamber 16 includes a beam stopper 38. The beam stopper 38 is fixed to the side wall 16 c of the implantation processing chamber 16. When the wafer W does not exist on the beam trajectory, the ion beam B enters the beam stopper 38. The beam stopper 38 is located near the carry-in / out port 80 connecting the implantation processing chamber 16 and the wafer transfer device 18, and is provided at a position vertically below the carry-in / out port 80.

  The implantation processing chamber 16 is provided with a second beam measuring instrument 44 for measuring the beam current amount of the ion beam and the beam current density distribution. The second beam measuring instrument 44 includes a side cup 40 (40R, 40L) and a center cup 42.

  The side cups 40R and 40L are arranged so as to be shifted in the x direction with respect to the wafer W, and are arranged at positions that do not block the ion beam directed toward the wafer W during ion implantation. Since the ion beam B is scanned in the x direction beyond the range where the wafer W is located, a part of the scanned beam is incident on the side cups 40R and 40L even at the time of ion implantation. Thereby, the beam current amount during the ion implantation process is measured. The measurement values of the side cups 40R and 40L are sent to the second beam measuring instrument 44.

  The center cup 42 is for measuring the beam current amount and the beam current density distribution on the surface (wafer processing surface) of the wafer W. The center cup 42 is movable, is retracted from the wafer position during ion implantation, and is inserted into the wafer position when the wafer W is not in the irradiation position. The center cup 42 measures the amount of beam current while moving in the x direction, and measures the beam current density distribution in the beam scanning direction. The measured value of the center cup 42 is sent to the second beam measuring instrument 44. The center cup 42 may be formed in an array in which a plurality of Faraday cups are arranged in the x direction so that the ion irradiation amounts at a plurality of positions in the beam scanning direction can be measured simultaneously.

  An energy slit 46 is provided in the implantation processing chamber 16. The energy slit 46 is provided on the downstream side of the angular energy filter 34 and performs energy analysis of the ion beam B incident on the wafer W together with the angular energy filter 34. The energy slit 46 is an energy limiting slit (EDS; Energy Defining Slit) formed of a horizontally long slit in the beam scanning direction (x direction). The energy slit 46 allows the ion beam B having a desired energy value or energy range to pass toward the wafer W and shields other ion beams.

  A plasma shower device 48 is provided in the implantation processing chamber 16. The plasma shower device 48 is located on the downstream side of the energy slit 46. The plasma shower device 48 supplies low energy electrons to the ion beam and the wafer processing surface according to the beam current amount of the ion beam B, and suppresses the charge-up of positive charges on the wafer processing surface caused by ion implantation. The plasma shower device 48 includes, for example, a shower tube through which the ion beam B passes, and a plasma generator that supplies electrons into the shower tube.

  An inspection device 60 is provided in the injection processing chamber 16. The inspection apparatus 60 is an apparatus for inspecting the position and orientation of the wafer W arranged at the inspection position shown in FIG. 3, and more specifically, alignment such as notches and orientation flats provided on the outer periphery of the wafer W. Optically inspect the position of the mark. The inspection device 60 includes an imaging device 62 for acquiring an image of the wafer W and an illumination device 72 for illuminating the wafer W. The imaging device 62 and the illumination device 72 are provided outside the implantation processing chamber 16, and inspect the wafer W through openings 16 d and 16 e provided on the wall surface of the implantation processing chamber 16. The optical axes C1 and C2 of the inspection apparatus 60 extend in the vertical direction, and are configured such that the imaging axis C1 and the illumination axis C2 are positioned on opposite sides of the wafer W at the inspection position.

  The imaging device 62 is a camera including an imaging element such as a CCD sensor or a CMOS sensor. The imaging device 62 is provided above the injection processing chamber 16 and images the inside of the injection processing chamber 16 through an upper opening 16 d provided in the upper wall 16 a of the injection processing chamber 16. An imaging outer window member 64 and an imaging inner window member 66 are provided so as to close the upper opening 16d. The imaging outer window member 64 is provided outside the injection processing chamber 16, and the imaging inner window member 66 is provided inside the injection processing chamber 16. The imaging window members 64 and 66 are plate-like members having translucency with respect to visible light, and are optical members made of, for example, a glass plate or a resin plate. An easily replaceable cover member such as a resin film may be added to the surface of the optical member.

  An imaging shielding member 68 is provided in the vicinity of the imaging inner window member 66. The imaging shielding member 68 is provided in the injection processing chamber 16, and prevents dirt from adhering to the exposed surface 66 a of the imaging inner window member 66 exposed inside the injection processing chamber 16. The imaging shielding member 68 is disposed so as to prevent the contaminants flying from the “beam collision point” that can become a contaminant generation source due to the collision of the ion beam B from directly adhering to the exposed surface 66a.

  FIG. 4 is a side view schematically showing the beam collision portions 82 a, 82 b, 82 c in the implantation processing chamber 16. The “beam collision point” in the present embodiment corresponds to an arbitrary object that can be placed on the beam trajectory in the implantation processing chamber 16. For example, the wafer W at the implantation position, the platen driving device 50, and the beam stopper. 38, the side cup 40, the center cup 42, the energy slit 46, the plasma shower device 48, and the like can be beam collision points. FIG. 4 shows an example of such a beam collision point, and illustrates a beam collision point 82 a in the energy slit 46, a beam collision point 82 b in the wafer W, and a beam collision point 82 c in the beam stopper 38.

  The imaging shielding member 68 is disposed between at least one of the beam collision locations and the exposed surface 66a of the imaging inner window member 66, and contaminants flying from the beam collision location adhere directly to the exposed surface 66a. Disturb. The imaging shielding member 68 is configured to shield contaminants flying from the wafer W at the implantation position, the platen driving device 50, and the center cup 42, for example. As shown in FIG. 4, the imaging shielding member 68 shields contaminants flying from the energy slit 46 and the beam collision portions 82 a and 82 b on the wafer W. As a result, the contaminated contaminant 84 accumulates on the outer surface of the imaging shielding member 68. The imaging shielding member 68 can be made of a material such as aluminum (Al) or graphite (C), for example.

  The imaging shielding member 68 is provided at a position avoiding the imaging axis C <b> 1 so as not to prevent imaging by the imaging device 62. Further, the imaging shielding member 68 is provided outside the movable range of the platen driving device 50 so as not to interfere with the operation of the platen driving device 50. For example, the length of the imaging shielding member 68 in the direction along the imaging axis C1 so that the imaging shielding member 68 is not located within the movable range of the platen driving device 50 indicated by the broken line R in FIGS. Or height) is limited.

  The imaging shielding member 68 is formed of a cylindrical member and is disposed so as to surround the imaging axis C <b> 1 of the imaging device 62. 5A to 5F are cross-sectional views schematically showing the configuration of the imaging shielding member 68, and show a cross section orthogonal to the imaging axis C1. For example, as shown in FIG. 5A, the imaging shielding member 68 is configured by a complete cylindrical member configured to surround the entire circumferential direction around the imaging axis C1. The imaging shielding member 68 may be an incomplete cylindrical member configured to partially surround a part in the circumferential direction, and a cross section orthogonal to the imaging axis C1 as shown in FIG. May be configured in a C shape, or a cross section orthogonal to the imaging axis C1 may be configured in an arc shape as shown in FIG. The imaging shielding member 68 may be formed of a rectangular tube member as shown in FIG. 5 (d), or partially in the circumferential direction as shown in FIGS. 5 (e) and 5 (f). It may be an incomplete square tubular member configured to surround. The imaging shielding member 68 may be a flat member.

  Returning to FIG. 3, the illumination device 72 includes a white light source such as an LED and illuminates the alignment mark of the wafer W to be imaged. The illumination device 72 is provided below the injection processing chamber 16 and illuminates the inside of the injection processing chamber 16 through a bottom opening 16e provided in the bottom wall 16b of the injection processing chamber 16. The outer window member for illumination 74 and the inner window member for illumination 76 are provided so as to close the bottom opening 16e. The illumination outer window member 74 is provided outside the injection processing chamber 16, and the illumination inner window member 76 is provided inside the injection processing chamber 16. The illumination window members 74 and 76 are plate-like members having translucency with respect to visible light, and are optical members made of, for example, a glass plate or a resin plate. An easily replaceable cover member such as a resin film may be added to the surface of the optical member.

  An illumination shielding member 78 is provided in the vicinity of the illumination inner window member 76. The illumination shielding member 78 is provided in the injection processing chamber 16, and, like the above-described imaging shielding member 68, dirt adheres to the exposed surface 76 a of the illumination inner window member 76 exposed inside the injection processing chamber 16. prevent. The illumination shielding member 78 is disposed between at least one of the above-mentioned “beam collision locations” and the exposed surface 76a of the illumination inner window member 76, and contaminants flying from the beam collision locations adhere directly to the exposed surface 76a. Prevent you from doing. As shown in FIG. 4, the illumination shielding member 78 is configured to shield contaminants flying from the beam stopper 38, for example. As a result, the contaminated contaminant 86 accumulates on the outer surface of the lighting shielding member 78. The illumination shielding member 78 can be made of a material such as aluminum (Al) or graphite (C), for example.

  The illumination shielding member 78 is provided at a position avoiding the illumination axis C2 so as not to prevent illumination by the illumination device 72. Further, the illumination shielding member 78 is provided outside the movable range of the platen driving device 50 so as not to interfere with the operation of the platen driving device 50. For example, the illumination shielding member 78 is cut obliquely with respect to the illumination axis C2 so that the illumination shielding member 78 is not located within the movable range of the platen driving device 50 indicated by the broken line R in FIGS. Have a different shape. Specifically, the length (or height) of the illumination shielding member 78 in the direction along the illumination axis C2 from the bottom wall 16b of the implantation processing chamber 16 is such that the side close to the beam stopper 38 (the right side of the drawing). It may be large and the side far from the beam stopper 38 (the left side of the paper) may be small.

  The illumination shielding member 78 is formed of a cylindrical member like the imaging shielding member 68 and is disposed so as to surround the illumination axis C <b> 2 of the illumination device 72. The illumination shielding member 78 may have a complete cylindrical or rectangular tube shape configured to surround the entire circumferential direction, like the imaging shielding member 68 shown in FIGS. 5 (a) to 5 (f). However, it may be an incomplete cylindrical or rectangular tube shape configured to partially surround a part in the circumferential direction. The illumination shielding member 78 may have another shape or may be a flat plate member.

  It is preferable that the optical member (the imaging inner window member 66 and the lighting inner window member 76) having the exposed surface is configured so that it can be easily replaced during maintenance. Similarly, it is preferable that the shielding members (the imaging shielding member 68 and the illumination shielding member 78) that prevent dirt from adhering to the exposed surface can be easily replaced during maintenance.

  In the state during wafer inspection shown in FIG. 3, the ion beam B is blocked on the upstream side from the implantation processing chamber 16 and the implantation processing chamber 16 is controlled not to be irradiated with the ion beam B. For example, as shown in FIG. 3, the ion beam B is blocked by a Faraday cup 24 b of the first beam measuring instrument 24. The ion beam B may be blocked at a place other than the first beam measuring device 24. For example, the ion beam B may be interrupted in the middle of the beam line device 14 by largely deflecting the beam so as to deviate from the normal scanning range of the beam scanner 26 and fixing the deflection direction. When the beam line device 14 interrupts the ion beam B during the wafer inspection, new contaminants are generated in the implantation processing chamber 16 during the wafer inspection, and dirt adheres to the exposed surfaces 66a and 76a of the window members. Can be prevented.

  Next, an operation flow of the ion implantation apparatus 10 will be described. First, as shown in FIG. 3, the unprocessed wafer W is carried into the implantation processing chamber 16 from the wafer transfer device 18 in a state where the ion beam B is interrupted in the middle of the beam line device 14. The unprocessed wafer W is placed at the inspection position and optically inspected by the inspection device 60. Based on the inspection result of the unprocessed wafer W, the reciprocating position of the reciprocating mechanism 54 in the Y direction can be adjusted, and the rotation angle of the wafer W by the twist angle adjusting mechanism 56 can be adjusted. Subsequently, the platen driving device 50 is rotated by the tilt angle adjusting mechanism 58, and the unprocessed wafer W is placed at the implantation position as shown in FIG. Thereafter, the blocking of the ion beam B is released, and an ion implantation process to the wafer W is executed according to a predetermined implantation recipe. After the implantation process is completed, the ion beam B is interrupted in the middle of the beam line device 14. The processed wafer W is returned from the implantation position shown in FIG. 2 to the inspection position shown in FIG. 3 and is carried out from the implantation processing chamber 16 to the wafer transfer device 18.

  According to the present embodiment, since the implantation process is performed after inspecting the position of the wafer W in the implantation processing chamber 16 using the inspection apparatus 60, the position accuracy of the implantation process can be improved. Of the optical members arranged on the optical axes C1 and C2 of the inspection apparatus 60, the optical members (the inner window member for imaging 66 and the inner window for illumination) having exposed surfaces 66a and 76a exposed in the injection processing chamber 16 are used. Since the shielding member (the imaging shielding member 68 and the illumination shielding member 78) is provided for the member 76), it is possible to prevent the contamination of the exposed surfaces 66a and 76a of the optical member. As a result, the amount and speed at which dirt accumulates on the exposed surfaces 66a and 76a of the optical member along with the long-term operation of the ion implantation apparatus 10 can be reduced, and a decrease in inspection accuracy due to the adhesion of dirt can be suitably suppressed. Therefore, according to the present embodiment, the long-term reliability of the wafer inspection process in the implantation processing chamber 16 can be improved. Moreover, according to this Embodiment, the maintenance frequency for dirt removal can be lowered | hung and the productivity of the ion implantation apparatus 10 can be raised.

  According to the present embodiment, the shielding members (imaging shielding member 68 and illumination shielding member 78) are exposed surfaces 66a, 82b, 82c to be shielded rather than the beam collision locations 82a, 82b, 82c that are the sources of contaminants. It is provided at a position close to 76a. By providing a shielding member in the vicinity of the exposed surfaces 66a and 76a to prevent the adhesion of dirt, even when there are a plurality of beam collision locations, the shielding performance against contaminants flying from the plurality of beam collision locations can be obtained. Can be increased. Thereby, the fall of the test | inspection precision by adhesion of dirt can be suppressed more suitably.

  As described above, the present invention has been described with reference to the above-described embodiments. However, the present invention is not limited to the above-described embodiments, and the configurations of the embodiments are appropriately combined or replaced. Those are also included in the present invention. Further, based on the knowledge of those skilled in the art, it is possible to appropriately change the combination and processing order in each embodiment and to add various modifications such as various design changes to the embodiment. Added embodiments may also fall within the scope of the present invention.

  FIG. 6 is a cross-sectional view showing a schematic configuration of an injection processing chamber 16 according to a modification. In this modification, the configuration of the illumination shielding member 90 is different from that of the above-described embodiment. The illumination shielding member 90 is provided not near the illumination inner window member 76 but near the beam stopper 38 which is one of the beam collision points. That is, the illumination shielding member 90 is provided closer to the beam stopper 38, which is the beam collision portion 82c, than the exposed surface 76a to which dirt is to be prevented.

  The illumination shielding member 90 is fixed to the beam stopper 38 and extends in the beam scanning direction (x direction) along the beam stopper 38. The illumination shielding member 90 is configured such that a cross section orthogonal to the beam scanning direction (x direction) is L-shaped, and extends vertically downward from the beam stopper 38 and then orthogonal to the surface of the beam stopper 38. It is configured to protrude and extend in the direction. Accordingly, the illumination shielding member 90 is disposed at a position between the beam stopper 38 and the exposed surface 76a of the illumination inner window member 76, and is disposed at a position avoiding the illumination axis C2.

  According to this modification, at least a part of the contaminant (contaminant 86 a) flying from the beam collision portion 82 c in the beam stopper 38 can be blocked by the illumination shielding member 90. Note that another part of the contaminant (contaminant 86b) flying from the beam collision point 82c in the beam stopper 38 is not shielded by the illumination shielding member 90, but as shown in FIG. It adheres to the position beyond 76. Therefore, also in this modification, the same effect as the above-mentioned embodiment can be produced.

  FIG. 7 is a cross-sectional view showing a schematic configuration of an injection processing chamber 16 according to another modification. This modification is different from the above-described embodiment in that an imaging device 162 provided in the inspection device 160 is provided on the side of the injection processing chamber 16. The imaging device 162 images the inside of the injection processing chamber 16 through a side opening 16f provided above the side wall 16c of the injection processing chamber 16 via an optical path changing mirror 165 provided in the middle of the imaging axis C1. The side opening 16f is closed by the imaging outer window member 164. The optical path changing mirror 165 is accommodated in a housing 169 provided in the injection processing chamber 16. An imaging inner window member 166 having an exposed surface 166a is provided on the imaging axis C1 reflected by the optical path changing mirror 165 and extending vertically downward. An imaging shielding member 168 is provided around the imaging inner window member 166. Also in this modification, the same effect as the above-mentioned embodiment can be produced.

  FIG. 8 is a cross-sectional view showing a schematic configuration of an implantation processing chamber 16 according to another modification. This modification differs from the above-described embodiment in that the imaging device 262 provided in the inspection device 260 is provided on the side of the injection processing chamber 16 and the illumination device 272 is provided above the injection processing chamber 16.

  The arrangement of the imaging device 262 is the same as that of the imaging device 162 according to the modified example of FIG. The imaging device 262 images the inside of the injection processing chamber 16 through a side opening 16f provided above the side wall 16c of the injection processing chamber 16 and a half mirror 265 provided in the middle of the optical axis C. The side opening 16 f is closed by the imaging outer window member 264, and the half mirror 265 is accommodated inside the housing 269.

  The arrangement of the illumination device 272 is the same as that of the imaging device 62 according to the above-described embodiment. The illumination device 272 illuminates the interior of the implantation processing chamber 16 through a half mirror 265 provided in the middle of the optical axis C through an upper opening 16 d provided in the upper wall 16 a of the implantation processing chamber 16.

  An inner window member 266 is provided below the half mirror 265 so as to close the opening of the housing 269. The inner window member 266 has an exposed surface 266 a that is exposed inside the injection processing chamber 16. A shielding member 268 is provided around the inner window member 266.

  Also in this modification, the same effect as the above-mentioned embodiment can be produced. Further, in this modification, since the optical axis C for imaging and illumination is common, the optical member having the exposed surface 266a exposed in the implantation processing chamber 16 can be integrated. Therefore, even if maintenance is required due to accumulation of dirt, only one optical member (inner window member 266) needs to be replaced, so that maintenance work can be reduced.

  In the above-described embodiment and modification, the configuration in which the exposed surface of the optical member arranged on the optical axis of the inspection apparatus is always exposed in the implantation processing chamber 16 has been described. In a further modification, a movable member that can temporarily cover the exposed surface of the optical member may be further provided. The movable member moves to a position intersecting the optical axis of the inspection apparatus when the ion beam B is irradiated onto the wafer W at the implantation position, and the exposed surface of the optical member is not exposed in the implantation processing chamber 16 during the beam irradiation. Like that. Further, when inspecting the wafer W at the inspection position, the movable member moves to a position not intersecting with the optical axis of the inspection apparatus so that the exposed surface of the optical member is exposed in the implantation processing chamber 16. According to this modification, it is possible to further suppress the adhesion of contaminants to the optical member having the exposed surface.

  In the above-described embodiment and modification, the case where the shielding member is disposed in the vicinity of the exposed surface of the optical member to be prevented from being attached with dirt or in the vicinity of the beam stopper 38 has been described. In a further modification, the shielding member may be disposed at a position closer to at least one of the beam collision positions in the implantation processing chamber 16 than the exposed surface of the optical member to be prevented from attaching dirt. Further, a shielding member may be arranged between the beam collision point in the beam line device 14 instead of the beam collision point in the implantation processing chamber 16. The beam collision location in the beam line device 14 may be, for example, the AEF electrode 36 of the angular energy filter 34.

  In the above-described embodiment, the case where the inspection device is disposed above and the illumination device is disposed below is shown. In a further modification, the inspection device and the illumination device may be arranged upside down.

  In the above-described embodiments and modifications, the inspection apparatus that captures and inspects the image of the wafer W has been described. In a further modification, an inspection apparatus that optically inspects the wafer W by irradiating the wafer W with laser light or the like and detecting reflected light or scattered light from the wafer W may be used.

  DESCRIPTION OF SYMBOLS 10 ... Ion implantation apparatus, 14 ... Beam line apparatus, 16 ... Implantation processing chamber, 50 ... Platen drive device, 60 ... Inspection apparatus, 62 ... Imaging apparatus, 68 ... Imaging shielding member, 72 ... Illumination apparatus, 78 ... For illumination Shield member 66a, 76a ... exposed surface, B ... ion beam, C1 ... imaging axis, C2 ... illumination axis, W ... wafer.

Claims (10)

An implantation processing chamber in which an ion beam is irradiated on the wafer;
A beamline device for providing an ion beam traveling along a predetermined beam trajectory in the implantation processing chamber;
An inspection apparatus for optically inspecting the wafer through an optical member having an exposed surface that can be exposed in the implantation processing chamber;
A position between a beam collision point that can be a source of contaminants by collision of the ion beam and the exposed surface of the optical member because it can be disposed on the beam trajectory in the implantation processing chamber; And a shielding member provided at a position avoiding the optical axis of the inspection apparatus. The wafer is provided in the implantation processing chamber and holds the wafer so that the wafer can move between an implantation position where the ion beam is irradiated onto the wafer and an inspection position where the wafer is inspected by the inspection apparatus. Further comprising a platen driving device,
The ion implantation apparatus according to claim 1, wherein the shielding member is fixed with respect to the implantation processing chamber, and is provided outside a movable range of the platen driving device as the wafer moves.   An optical axis of the inspection apparatus extends in a direction intersecting the beam trajectory, intersects with the wafer at the inspection position, and is provided at a position not intersecting with the wafer at the implantation position. The ion implantation apparatus according to claim 2. At least one of the beam collision points is the wafer or the platen driving device at the implantation position,
The ion implantation apparatus according to claim 2, wherein at least one of the shielding members is provided at a position closer to the exposed surface than at least one of the beam collision portions. At least one of the beam collision points is a beam stopper provided on the downstream side of the wafer or the platen driving device at the implantation position,
5. The ion implantation apparatus according to claim 2, wherein at least one of the shielding members is provided at a position closer to the beam stopper than the exposed surface. 6.   6. The ion implantation apparatus according to claim 1, wherein the shielding member includes a cylindrical member that surrounds a whole or a part of a circumferential direction around the optical axis of the inspection apparatus.   The shielding member includes a movable member disposed so as to intersect with an optical axis of the inspection apparatus when the wafer is irradiated with a beam and not to intersect with an optical axis of the inspection apparatus when the wafer is inspected. The ion implantation apparatus according to any one of claims 1 to 6.   The ion implantation apparatus according to claim 1, wherein the shielding member is provided at a plurality of locations in the implantation processing chamber.   9. The ion implantation apparatus according to claim 1, wherein the beam line device blocks the ion beam upstream of the implantation processing chamber when the wafer is inspected. 10. The inspection apparatus includes an illumination device that illuminates the wafer and an imaging device that images the wafer, and each of an illumination axis that faces the wafer and an imaging axis that faces the wafer is located on the opposite side across the wafer Configured to
The shielding member includes: an illumination shielding member disposed between an exposed surface of the illumination optical member disposed on the illumination axis and the beam collision location; and an imaging optical member disposed on the imaging axis. The ion implantation apparatus according to claim 1, further comprising at least one of an imaging shielding member disposed between an exposed surface and the beam collision portion.

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