JP2013161858A - Charged particle beam drawing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charged particle beam drawing apparatus capable of improving the throughput of drawing processing by shortening a settling time and a drawing time of a deflection amplifier by reducing the impedance of an external conductor in a line from the deflection amplifier to a deflection plate which branches off halfway as multiple stages of deflectors are provided, and then reducing crosstalk between lines.SOLUTION: A charged particle beam drawing apparatus includes a drawing section 2 which draws a pattern on a sample placed on a movable stage by deflecting a charged particle beam EB using a deflector 52, and a control section 3 comprising a deflection control section 32 which controls the deflection of the charged particle beam EB, and a control computer 31 which performs control over the deflection control section 32. A deflector 51 includes a deflection plate 53 which deflects the charged particle beam EB and a cable 54 which applies a control signal from the deflection control section 32 to the deflection plate 53 through the deflection amplifier, and has its periphery covered with a block B having a reference potential of 0 V.

Description

  The present invention relates to a charged particle beam drawing apparatus.

  Lithography technology is used to form a desired circuit pattern on a semiconductor device. In the lithography technique, a pattern is transferred using an original pattern called a mask (also referred to as a reticle; hereinafter referred to as “mask” or “sample”). At this time, in order to manufacture a highly accurate mask, an electron beam (electron beam) drawing technique having an excellent resolution is used.

  An example of a charged particle beam writing apparatus that performs electron beam writing on a mask includes the following variable forming method. That is, although not shown here, this variable forming method is performed on the sample placed on the movable stage by the electron beam formed by passing through the opening of the first forming aperture and the opening of the second forming aperture. A graphic pattern is drawn.

  In recent years, shortening of drawing time on a sample and improvement of drawing accuracy have been demanded. There is also a demand for miniaturization of the device itself. In order to meet these requirements, for example, assuming a field (for example, a main field and a subfield) having two different unit areas on the sample, a subfield having a smaller drawing area is drawn at a high speed. By doing so, the overall drawing time is reduced.

  Further, in order to draw with high accuracy at any drawing position on the mask M, it is necessary to increase the deflection sensitivity. Therefore, deflectors are arranged in multiple stages so that the electron beam can be quickly moved to a predetermined drawing position.

  However, when a plurality of drawing areas are assumed, a deflector is required for each, such as a main deflector corresponding to a main field and a sub deflector corresponding to a subfield. Made. If each deflector includes, for example, 8 deflecting plates (8 poles), 16 deflectors in 2 stages and 32 deflectors in 4 stages are provided. The cable will be connected. Therefore, in such a case, the structure of the deflector must be complicated.

  FIG. 6 is an explanatory diagram showing a wiring state of a deflector currently used. As shown in FIG. 6, there is an electron lens barrel 100 indicated by a broken line extending vertically in the center, and a deflector 101 is housed therein. Since FIG. 6 shows a state in which the electronic lens barrel 100 is removed, the deflector 101 and a plurality of cables 102 wired around the deflector 101 can be seen. A deflector plate (not shown) or the like is provided inside the deflector 101, the surface of the deflector plate is disposed so as to face the electron beam, and a cable 102 for supplying a deflection voltage applied from a deflection amplifier on the back surface thereof. Is connected to the electrode 103.

Further, the deflector 101 shown in FIG. 6 is provided with two stages of main field deflectors and two stages of subfield deflectors, for a total of four stages. The main field deflector and the sub field deflector are alternately arranged, and the first main field deflector from the lower side toward the electron gun from the side close to the sample. 101a, the first subfield deflector 101b, the second main field deflector 101c, and the second subfield deflector 101d. When these deflectors are collectively represented, they are appropriately represented as the deflector 101 as before.

  The deflection amplifier and each deflector are connected by a cable 102. For example, if there are 8-pole deflectors for the main field and the sub-field, they are connected to the respective deflectors via a total of 16 connectors 101e.

  For example, the cable 102 is connected to the connector 101e, is connected to the second subfield deflector 101d (deflecting plate) by the electrode 103d, and then is further connected to the first subfield deflector 101b by the electrode 103b. It will be connected to (deflection plate).

  FIG. 7 is a schematic diagram showing a connection state between each deflection plate and the deflection amplifier. Here, only one of the deflection plates included in each deflector is shown. The deflection plate 101aa of the first main field deflector 101a, the deflection plate 101ba of the first subfield deflector 101b, the deflection plate 101ca of the second main field deflector 101c, and the second subfield deflection, respectively. This is a deflection plate 101da of the device 101d.

  Of the deflecting plates, the side to which the reference numeral is attached is the surface that becomes the optical path of the electron beam, and the surface to which the cable 102 is connected is the back surface of the deflecting plate that includes the electrodes. Here, a coaxial cable is used as the cable 102. However, the outer conductor of the coaxial cable is peeled off and the center conductor is connected to the connection portion between the electrode of the deflection plate and the deflection amplifier.

  As described above, the deflector 101 is alternately arranged for the main field and the subfield. However, each deflection amplifier is not provided independently for each deflector, but the first A deflection voltage is applied from the same main deflection amplifier 36 to the main field deflector 101a and the second main field deflector 101c. Similarly, a deflection voltage is applied to the first subfield deflector 101b and the second subfield deflector 101d from the same subdeflection amplifier 35.

  Therefore, as shown in FIG. 7, for example, the main deflection amplifier 36 is connected to the electrode of the second main field deflector 101c (deflection plate 101ca) using one coaxial cable 104, and then the first Are connected to the electrodes of the main field deflector 101a (deflection plate 101aa). Therefore, the second main field deflector 101c and the first main field deflector 101a are connected in series. In the connection between the electrode of each deflecting plate and the coaxial cable 104, only the central conductor 104a is connected as described above, and therefore, the outer conductor serving as a shield is peeled off at this electrode portion.

  The deflection amplifier and the deflection plate of the deflector 101 are connected as shown in FIG. 7. Here, the exposure of the center conductor 104a at the electrode connection portion causes various adverse effects.

  That is, as shown in FIG. 6, the cable 102 (coaxial cable 104) for connecting the electrode of the deflection plate and the deflection amplifier is connected as shown in FIG. For this reason, the cables 102 (coaxial cables 104) having different applied voltage values are arranged adjacent to each other, for example, so that a complicated operation is performed. Further, since the distance between adjacent deflecting plates is short, each electrode is also in a close position. Therefore, a state in which conductors without external conductors are connected at positions close to each other is created, and the impedance with respect to 0 V potential (GND potential) becomes very large.

  Further, since a deflection voltage is applied from a deflection amplifier with one signal line to a deflection plate provided in a plurality of stages of deflectors, there is a branch on the way. This makes it difficult to keep the characteristic impedance of the cable 102 between the deflection amplifier and the deflection plate constant.

  That is, when a signal having a high frequency component is transmitted by the cable 102, leakage of electromagnetic waves from the central conductor 104a to the surroundings occurs at the branching portion. Therefore, the signal reaching the 101ba through the central conductor 104a and the external conductor are transmitted. Thus, a difference occurs in the signals returned from 101ba. This increases the impedance of the center conductor 104a and the outer conductor of the cable 102 for high-frequency signals. For this reason, even if a part of the outer conductor, such as the tip of the outer conductor, is set at the GND potential, the time required for the other part of the outer conductor to reach the GND potential is extended, and the potential of the outer conductor at that part easily changes due to external noise. Therefore, the shielding effect of the cable 102 is weakened, and a state called crosstalk (crosstalk) in which a signal leaks to another adjacent cable 102 occurs.

  When this state occurs, for example, when the voltage applied to the second subfield deflector 101d for subfield drawing processing changes, for example, the voltage is applied to the second main field deflector 101c. It is possible to grasp a phenomenon in which a long time constant unintentionally changes in the voltage to be generated. When this state occurs, the drawing process using the second subfield deflector 101d is forced to stop until the second main field deflector 101c is settled in order to perform a highly accurate drawing process. .

  If this state continues, as a result, the waiting time for the settling time of others will increase, and as a result, the throughput of the entire drawing process will deteriorate.

  In order to deal with such a problem, in the invention disclosed in Patent Document 1 below, the electrodes of two deflectors arranged separately are connected by a single-core cable, and in series with the single-core cable. This is dealt with by connecting a damping resistor. As a result, the undulation component of ringing can be attenuated, and the deflection system can be improved.

JP 2007-48805 A

  However, in the invention described in Patent Document 1, although the damping resistor is connected, the electrodes of the two deflectors are eventually connected by a single-core cable. In this case, the cable shield is weak, and it is difficult to avoid the above-described adverse effects.

  Further, as a countermeasure against the above-described adverse effects, for example, the outer conductor of the cable 102 that is routed around the deflector 101 is bound to a GND potential block with a conductive object (for example, a copper wire or a wire clamp). A method of increasing the shielding effect by keeping the potential at the GND potential is also conceivable.

  However, even with this method, for example, since the contact between the cable 102 and the block is not uniform, the crosstalk amount varies for each cable. Further, the wiring method is often different for each charged particle beam drawing apparatus, and this is generally unacceptable as a method for avoiding the above-described adverse effects. Furthermore, since an object for fixing the cable 102 to the GND potential block is required, it is not preferable that the number of parts of the entire apparatus increases.

  In addition, since the impedance of the external conductor is high, the number of locations where the GND potential block and the external conductor are in contact with each other is insufficient, and it is necessary to contact the GND potential block with the external conductor at multiple points or the entire cable. The number of parts increases significantly.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce the impedance of an external conductor in a line from a deflection amplifier to a deflecting plate, where branching occurs in the middle as the number of deflectors increases. The charged particle beam drawing apparatus is capable of reducing the settling time and drawing time of the deflection amplifier and improving the throughput of drawing processing by reducing crosstalk between lines.

  A feature according to an embodiment of the present invention is that, in a charged particle beam drawing apparatus, a drawing unit that draws a pattern on a sample placed on a movable stage by deflecting a charged particle beam using a deflector; A control unit configured by a deflection control unit that controls deflection of the charged particle beam, a stage control unit that controls movement of the stage, and a control computer that controls the deflection control unit and the stage control unit, The deflector includes a deflection plate that deflects a charged particle beam, and a cable that applies a control signal from the deflection control unit to the deflection plate via a deflection amplifier and is covered with a block having a reference potential of 0 volts. With.

  A feature according to an embodiment of the present invention is that, in a charged particle beam drawing apparatus, a drawing unit that draws a pattern on a sample placed on a movable stage by deflecting a charged particle beam using a deflector; A control unit configured by a deflection control unit that controls deflection of the charged particle beam, a stage control unit that controls movement of the stage, and a control computer that controls the deflection control unit and the stage control unit, The deflector holds the deflection plate facing the optical path of the charged particle beam, a deflection plate for deflecting the charged particle beam, a cable for applying a control signal from the deflection control unit to the deflection plate via a deflection amplifier, and And a block having a reference potential of 0 volts provided with a hole for passing a cable therein.

  In the charged particle beam drawing apparatus, the deflector is preferably composed of a plurality of stages of main deflectors and a plurality of stages of sub-deflectors.

  Further, in the charged particle beam drawing apparatus, the block is preferably made of a metal having excellent conductivity, and is preferably composed of a single body or a plurality of masses that can be combined.

  In the charged particle beam drawing apparatus, it is desirable that the cable passing through the block is composed of at least a conductor and an insulator covering the periphery of the conductor.

  According to the present invention, it is possible to reduce the impedance of the external conductor in the line from the deflection amplifier to the deflection plate where branching occurs in the middle as the number of deflectors increases, and to reduce crosstalk between the lines, thereby reducing the deflection amplifier. It is possible to provide a charged particle beam drawing apparatus capable of shortening the settling time and the drawing time and improving the drawing processing throughput.

1 is a block diagram illustrating an overall configuration of a charged particle beam drawing apparatus according to an embodiment of the present invention. It is explanatory drawing which shows the external structure of the deflector in embodiment of this invention. It is explanatory drawing showing the inside of the deflector in embodiment of this invention. It is the perspective view which appeared diagonally after cutting the deflector in the embodiment of the present invention horizontally. It is a perspective view which shows the hole through which an internal cable passes while it appears diagonally after cutting the deflector in embodiment of this invention horizontally. It is explanatory drawing which shows the wiring state of the deflector currently utilized. It is a schematic diagram which shows the connection state of each deflection plate and deflection amplifier.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing an overall configuration of a charged particle beam drawing apparatus 1 according to an embodiment of the present invention. In the following embodiments, a configuration using an electron beam as an example of a charged particle beam will be described. However, the charged particle beam is not limited to an electron beam, and may be a beam using charged particles such as an ion beam.

  The charged particle beam drawing apparatus 1 is an apparatus that draws a predetermined pattern on a sample, and is particularly an example of a variable shaping type drawing apparatus. As shown in FIG. 1, the charged particle beam drawing apparatus 1 includes a drawing unit 2 and a control unit 3. The drawing unit 2 includes an electron column 4 and a drawing chamber 6.

  In the electron column 4, along an optical path of an electron gun 41 and a charged particle beam (electron beam) EB irradiated from the electron gun 41, an illumination lens 42, a blanking deflector 43, and a blanking aperture are provided. 44, a first shaping aperture 45, a projection lens 46, a shaping deflector 47, a second shaping aperture 48, an objective lens 49, a second subfield deflector 50b, a second main A field deflector 51b, a first subfield deflector 50a, and a first main field deflector 51a are sequentially arranged.

  In the following description, the first subfield deflector 50a and the second subfield deflector 50b are collectively referred to as “subfield deflector 50”. Similarly, the first main field deflector 51a and the second main field deflector 51b are collectively referred to as “main field deflector 51”. In the embodiment of the present invention, “main field deflector” corresponds to “main deflector”, and “subfield deflector” corresponds to “sub deflector”.

  A movable XY stage 61 is disposed in the drawing chamber 6. On the XY stage 61, a sample M such as a mask that becomes a sample at the time of drawing is arranged. The sample M is not actually placed directly on the XY stage 61 but is held by a holding member provided between the XY stage 61 and the sample M, but the illustration is omitted in FIG.

  The blanking deflector 43 is constituted by a plurality of electrodes such as two poles or four poles. In addition, the shaping deflector 47, the subfield deflector 50, and the main field deflector 51 are configured by a plurality of electrodes, for example, 4 poles or 8 poles. In FIG. 1, only one deflection amplifier is shown for each of the shaping deflector 47, the subfield deflector 50, the main field deflector 51, and each deflector. However, at least one deflection amplifier is provided for each pole. Connected.

  The control unit 3 includes a control computer 31, a deflection control unit 32, a blanking amplifier 33, a shaping deflection amplifier 34, a sub deflection amplifier 35, a main deflection amplifier 36, and a stage control unit 37. Although not shown in FIG. 1, the control computer 31 has an external interface (I / I) for connecting a storage device such as a memory or a magnetic disk device or the charged particle beam drawing apparatus 1 to the outside. F) A circuit may be provided.

The control computer 31 mainly controls the deflection control unit 32 and the stage control unit 37. In addition, the entire charged particle beam drawing apparatus 1 is also controlled. The control computer 31 generates shot data such as the division of the graphic pattern and the irradiation amount of the electron beam EB necessary for performing the electron beam EB shot on the graphic pattern, and transmits the shot data to the deflection control unit 32.

  In the control computer 31 shown in FIG. 1, for example, each unit necessary for performing the role required for the control computer 31 in the charged particle beam drawing apparatus 1 such as a determination unit and a calculation unit is provided. Here, since it is not particularly necessary to describe the embodiment of the present invention, the configuration of each of these parts is not shown. Each of these units may be configured by software such as a program or hardware, or may be configured by a combination of software and hardware. When these units are configured to include software as described above, the input data input to the control computer 31 or the calculated result is stored in a memory (not shown) each time.

  Based on the shot data generated by the control computer 31, the deflection control unit 32 performs deflection control on the shaping deflection amplifier 34, the sub deflection amplifier 35, and the main deflection amplifier 36 upon irradiation with the electron beam EB.

  The control computer 31, the deflection control unit 32, and the stage control unit 37 are connected to each other via a bus (not shown). The deflection control unit 32, the blanking amplifier 33, the shaping deflection amplifier 34, the sub deflection amplifier 35, and the main deflection amplifier 36 are connected to each other via a bus (not shown). In the following, the shaping deflection amplifier 34, the sub deflection amplifier 35, and the main deflection amplifier 36 are collectively referred to as “deflection amplifier” as appropriate.

  The blanking amplifier 33 is connected to the blanking deflector 43. The shaping deflection amplifier 34 is connected to a shaping deflector 47. The sub deflection amplifier 35 is connected to the sub field deflector 50, and the main deflection amplifier 36 is connected to the main field deflector 51. Independent control digital signals are output from the deflection control unit 32 to the blanking amplifier 33, the shaping deflection amplifier 34, the sub deflection amplifier 35, and the main deflection amplifier 36.

  The shaping deflection amplifier 34, the sub deflection amplifier 35, and the main deflection amplifier 36 to which the digital signal is inputted convert each digital signal into an analog voltage signal, amplify it, and output it to each deflector connected as a deflection voltage. In this way, a deflection voltage is applied to each deflector from the deflection amplifier connected thereto. The electron beam EB is deflected by the deflection voltage.

  The charged particle beam drawing apparatus 1 is provided with four or eight poles of the shaping deflector 47, the subfield deflector 50, and the main field deflector 51 so as to surround the electron beam EB as described above. A pair (two pairs in the case of four poles, four pairs in the case of eight poles) is arranged with the electron beam EB interposed therebetween. A deflection amplifier is connected to each of the shaping deflector 47, the subfield deflector 50, and the main field deflector 51. However, FIG. 1 shows only one deflection amplifier connected to the shaping deflector 47, the subfield deflector 50, and the main field deflector 51, and omits the display of the other deflection amplifiers. Yes.

  The method of connecting the sub deflection amplifier 35 or the main deflection amplifier 36 to the sub field deflector 50 and the main field deflector 51 is as shown in FIG. That is, the subfield deflector 50 and the main field deflector 51 are alternately arranged for the main field and the subfield, but each deflection amplifier is provided independently for each deflector. Instead, the first main field deflector 51 a and the second main field deflector 51 b are applied with a deflection voltage from the same main deflection amplifier 36. Similarly, the first subfield deflector 50a and the second subfield deflector 50b are applied with a deflection voltage from the same subdeflection amplifier 35.

  Therefore, as shown in FIG. 1, for example, from the main deflection amplifier 36, the first main field deflector 51a and the second main field deflector 51b are connected in series using one coaxial cable. Will be connected.

  The stage control unit 37 is connected to the XY stage 61 and the control computer 31, detects the movement of the XY stage 61, and performs drawing processing so that the sample M placed on the XY stage 61 is at a desired position. The XY stage 61 is moved according to the above.

  Note that the charged particle beam drawing apparatus 1 in the embodiment of the present invention shown in FIG. 1 shows only the configuration necessary for describing the embodiment of the present invention. Accordingly, other configurations such as a control circuit for controlling each lens may be added.

  The charged particle beam drawing apparatus 1 operates as follows to perform drawing on a drawing target. When the electron beam EB emitted from the electron gun 41 (emission unit) passes through the blanking deflector 43, the electron beam EB is blanked when the blanking deflector 43 is turned on. Is controlled to pass through. On the other hand, in the OFF state, the entire electron beam EB is deflected so as to be shielded by the blanking aperture 44 (indicated by a broken line in FIG. 1). The electron beam EB that has passed through the blanking aperture 44 until the deflection voltage from the blanking amplifier 33 is turned from OFF to ON and then turned OFF again becomes one electron beam shot.

  A deflection voltage that alternately generates a state in which the electron beam EB passes through the blanking aperture 44 and a state in which the electron beam EB is blocked by the blanking aperture 44 is output from the blanking amplifier 33. The blanking deflector 43 controls the direction of the passing electron beam EB by the deflection voltage output from the blanking amplifier 33, and the electron beam EB passes through the blanking aperture 44. Alternately create shielded states.

  As described above, the electron beam EB of each shot generated by passing through the blanking deflector 43 and the blanking aperture 44 is rectangular by the illumination lens 42, for example, a first shaping aperture 45 having a rectangular hole. Illuminate the whole. Here, the electron beam EB is first shaped into a rectangle, for example, a rectangle. Then, the electron beam EB of the first aperture image that has passed through the first shaping aperture 45 is projected on the second shaping aperture 48 by the projection lens 46. The first aperture on the second shaping aperture 48 is formed by a shaping deflector 47 to which a deflection voltage for controlling the direction of the electron beam EB that has passed through the first shaping aperture 45 is applied from the shaping deflection amplifier 34. The image is deflection controlled and the beam shape and dimensions can be changed.

  A deflection voltage for controlling the irradiation position of the electron beam EB that has passed through the second shaping aperture 48 is supplied from the sub deflection amplifier 35 to the sub field deflector 50, and from the main deflection amplifier 36 to the main field deflector 51. Is output for. The electron beam EB that has passed through the second shaping aperture 48 and formed into the second aperture image is focused by the objective lens 49 and is placed at a desired position on the sample M arranged on the XY stage 61 that moves continuously. Irradiated.

  Next, the configuration of the deflector in the embodiment of the present invention will be described. FIG. 2 is an explanatory diagram showing the external configuration of the deflector according to the embodiment of the present invention. In the following, the subfield deflector 50 and the main field deflector 51 are collectively referred to as a “deflector 52” as appropriate.

  The deflector 52 has a substantially cylindrical shape, and is usually housed in the electron column 4. FIG. 3 and FIG. 4 to be described later show the deflector 52 in an extracted manner. The deflector 52 includes, from above, a connector 52a, a second subfield deflector 50b, a second main field deflector 51b, a first subfield deflector 50a, and a first main field deflector 51a. , In this order. The connector 52a is on the electron gun 41 side, and the first main field deflector 51a is in a position facing the sample M.

  The deflector 52 is formed of, for example, a metal block (block). For this block B, for example, a metal having excellent electrical conductivity such as titanium (Ti) and strength can be suitably used.

  Here, it is required to have strength. When a very fine figure is drawn on the sample M, distortion and deformation of the device hinder high-precision drawing processing. The deflection plate 53 constituting the deflector 52 is fixed to the block B. For example, if the fixing torque of the deflection plate 53 is too strong, the deflection plate 53 is distorted or the block B itself is deformed. It is also possible to do. It is also conceivable that the deflector 52 is deformed by atmospheric pressure, thermal expansion, or the like. Therefore, in order to avoid such an adverse effect, the block B is required to have a considerable strength.

  Further, the block B forming the deflector 52 has a reference potential of 0 volts, that is, a GND potential. This is because the hole 55 is formed in the block B (deflector 52), and the single-core cable 54 is passed through the hole 55 to reduce the impedance in the signal line from the deflection amplifier to the deflection plate. .

  In forming the block B, it may be formed based on a single block, or a desired block B may be formed by combining a plurality of blocks. When combining a plurality of lumps as in the latter, it is required to combine the blocks so as to reduce the impedance between the blocks by bringing them into contact with each other with the largest possible area and surface pressure. By doing so, the impedance of the block B can be reduced.

  Further, as will be described later, a hole for allowing the cable 54 to pass through is appropriately formed inside the block B.

  The connector 52 a is connected to a cable 54 (not shown) that transmits a deflection voltage output from the deflection amplifier to the deflector 52. The connector 52 a is formed so as to open to connect the outside and the inside of the deflector 52. Accordingly, when the cable 54 connected to the connector 52a from the outside of the block B passes through the connector 52a, the cable 54 enters the block B and is connected to a desired electrode.

  For example, when each of the main field deflector 51 and the subfield deflector 50 includes eight deflecting plates 53 (eight poles), each of the cables 54 for applying a voltage to each deflecting plate has eight cables 54. A total of 16 books are required. Accordingly, the number of connectors 52 a is 16 and provided around the deflector 52. Hereinafter, the deflector 52 in the embodiment of the present invention will be described on the assumption that eight deflecting plates 53 are provided.

Further, in order to connect the cables 54 to the respective deflection plates 53, connection lateral holes 52 b are provided around the deflectors 52 in accordance with the positions of the electrodes 53 a provided on the respective deflection plates 53. . When the cable 54 passes through the hole provided in the block B, it becomes difficult to connect the cable 54 to the electrode 53a provided in the deflection plate 53. However, the connection side hole 52b It is provided for ease.

  In addition, the electrode 53a of the deflection plate 53 is visible in the back of the connecting horizontal hole 52b provided in the block B shown in FIG. 2, and further, the state in which the cable 54 is connected to the electrode 53a is shown. Yes. When the cable 54 is connected to the electrode 53a, the covering is peeled off and the internal conductor 54a is connected.

  In addition, for example, the voltage applied from the sub deflection amplifier 35 is first applied from the sub deflection amplifier 35 to the electrode 53a of the second sub field deflector 50b via the cable 54, and then, for the first sub field. Applied to the deflector 50a. For this reason, in the connecting horizontal hole 52b of the second subfield deflector 50b shown in FIG. 2, the state in which the conductor of the cable 54 is connected so as to cut through the connecting horizontal hole 52b is shown. Then, since the cable 54 is connected to the first subfield deflector 50a following the second subfield deflector 50b, this state is shown. However, after connecting to the first sub-field deflector 50a, there is no deflector 52 to be connected next, so that the cable 54 is not shown to be connected next.

  FIG. 3 is an explanatory diagram showing the inside of the deflector 52 in the embodiment of the present invention. Actually, since the deflector 52 is formed of the metal block B, the inside cannot be seen. However, for convenience of explanation, FIG. 3 shows the inside so that it can be seen.

  A hole 55 through which the cable 54 passes is provided inside the deflector 52 in the embodiment of the present invention. The hole 55 is a hole through which the cable 54 connecting the second subfield deflector 50b and the first subfield deflector 50a is passed. Similarly, the hole 55 is also provided for the cable 54 connecting the first main field deflector 51b and the first main field deflector 51a.

  In forming the hole 55 inside the block B, as described above, the hole 55 may be formed by drilling a hole at a desired position of the block B which is a single block, or the holes 55 may be formed in a plurality of blocks. It is also possible to form the desired hole 55 by forming grooves and the like to be formed in advance and combining them.

  Further, the positions and paths of the holes shown in FIG. 3 are merely examples. Taking the hole 55 shown in FIG. 3 as an example, the cable 54A connected to the connector 52aa is connected to the electrode 53a of the second subfield deflector 50b, and then passes through the hole 55a. Thus, the first subfield deflector 50a is connected to the electrode 53a.

  On the other hand, the cable 54B connected to the connector 52ab is connected to the electrode 53a of the second main field deflector 51b and then connected to the electrode 53a of the first main field deflector 51a through the hole 55b. Is done.

  FIG. 4 is a perspective view showing the deflector 52 in the embodiment of the present invention obliquely after being cut horizontally. FIG. 5 is a perspective view showing the hole 55 through which the deflector 52 in the embodiment of the present invention is cut horizontally and appears obliquely and through which the internal cable 54 passes.

4 and 5 are such that the deflector 52 shown in FIG. 2 or FIG. 3 is cut in the horizontal direction (direction perpendicular to the irradiation direction of the electron beam EB) and the optical path of the electron beam EB is looked into. It is the represented perspective view. In the optical path of the electron beam EB, the surface of the deflection plate 53 is provided so as to face the electron beam EB. In addition, the electrode 53a provided on the back surface of the deflection plate 53 can be accessed through the connecting lateral hole 52b, and the cable 54 is connected to the electrode 53a using the connecting lateral hole 52b.

  Since FIG. 4 shows only the outside of the deflector 52, the hole 55 formed therein cannot be seen. On the other hand, FIG. 5 shows that the inside of the deflector 52 can be seen. Unlike the path of the hole 55 shown in FIG. 3, the hole 55 shown in FIG. 5 is formed, for example, gently curved from the connector 52a, that is, toward the sample M. Thus, the path of the hole 55 can be freely formed in consideration of the position of the deflecting plate 53 (electrode 53a) to be connected, the bending ease of the cable 54, and the like.

  For example, the diameter of the hole 55 can be determined in accordance with the cable 54 to be passed. In the embodiment of the present invention, the cable 54 passes through the hole 55 formed in the deflector 52, so that the impedance of the cable 54 is reduced. Therefore, as described above, the block B constituting the deflector 52 has a GND potential.

  By arranging the cable 54 in the hole 55 formed in the deflector 52, the block B having the GND potential can be used as the outer conductor of the cable 54 having a shielding effect. In any of these locations, a low impedance with respect to the GND potential can be maintained. If the low impedance can be maintained, the cable 54 is adequately shielded, and as a result, it is possible to avoid the occurrence of a harmful effect such as crosstalk.

  Therefore, for example, it is desirable that the hole 55 is formed to have a size that covers the periphery of the cable 54 in close contact. Alternatively, the degree of adhesion can be increased by making the diameter of the hole 55 slightly smaller than the diameter of the cable 54. Accordingly, the diameter of the hole 55 through which the cable 54 passes can be freely set depending on the type of the cable 54.

  Here, as the cable 54, for example, a coaxial cable having no protective film outside the outer conductor can be used. In the coaxial cable, an insulator is coated around the conductor, and an outer conductor such as a mesh wire is formed on the outer periphery thereof. By appropriately selecting the outer diameter of the coaxial cable and the inner diameter of the hole 55, the outer conductor of the coaxial cable uniformly contacts the block B having the GND potential over a wide area, so that the impedance of the outer conductor with respect to the GND potential is lowered and high. A shielding effect can be obtained.

  When a cable composed of at least a conductor and an insulator provided around the conductor is used as the cable 54, the conductor diameter of the cable, the dielectric constant of the insulation coating, and the hole diameter are applied to the following equations so that a desired impedance is obtained. It is necessary to select the optimal cable.

  Here, “K” represents a constant, “ε” represents the relative dielectric constant of the insulator, “D” represents the hole diameter (mm), and “d” represents the center diameter (mm) of the conductor.

  By adopting the configuration described above, the impedance of the line from the deflection amplifier to the deflection plate where the branching occurs along with the multi-stage of the deflector is reduced, and the crosstalk between the lines is reduced, thereby reducing the deflection amplifier. Therefore, it is possible to provide a charged particle beam drawing apparatus capable of shortening the settling time and drawing time of the above and improving the throughput of the drawing process.

  In particular, when the hole provided in the block is used as a signal line, a good shielding effect can be obtained uniformly over the entire signal line. Therefore, crosstalk between lines can be effectively reduced.

  In addition, by providing the hole through which the cable passes inside the deflector as described above, for example, it is possible to reduce the parts used to collect the cables wired outside the deflector as before. Furthermore, since the number of parts is reduced and the holes for passing cables are formed in the deflector in advance, it is possible to reduce the labor and time for assembling the deflector and reduce mounting errors and work efficiency. Can be improved.

  Further, by adopting a cable made of a conductor and an insulator provided around the conductor, the outer conductor can be eliminated, so that the number of parts can be further reduced, or a cheaper cable can be adopted. Further, since no network line chips are generated, processing of the network terminal is not required.

  Although an embodiment of the present invention has been described, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Charged particle beam drawing apparatus 2 Drawing part 3 Control part 31 Control computer 32 Deflection control part 33 Blanking amplifier 34 Shaping deflection amplifier 35 Sub deflection amplifier 36 Main deflection amplifier 50a First subfield deflector 50b Second subfield Deflector 51a first main field deflector 51b second main field deflector 52 deflector 52a connector 53 deflector plate 53a electrode 54 cable 55 hole B block

Claims (5)

A drawing unit that deflects a charged particle beam using a deflector and draws a pattern on a sample placed on a movable stage; and
A control unit configured by a deflection control unit that controls deflection of the charged particle beam, a stage control unit that controls movement of the stage, and a control computer that controls the deflection control unit and the stage control unit; With
The deflector is
A deflection plate for deflecting the charged particle beam;
Applying a control signal from the deflection control unit to the deflection plate via a deflection amplifier, and surrounding the cable with a block having a reference potential of 0 volts;
A charged particle beam drawing apparatus comprising: A drawing unit that deflects a charged particle beam using a deflector and draws a pattern on a sample placed on a movable stage; and
A control unit configured by a deflection control unit that controls deflection of the charged particle beam, a stage control unit that controls movement of the stage, and a control computer that controls the deflection control unit and the stage control unit; With
The deflector is
A deflection plate for deflecting the charged particle beam;
A cable for applying a control signal from the deflection control unit to the deflection plate via a deflection amplifier;
A block having a reference potential of 0 volts, which holds the deflecting plate facing the optical path of the charged particle beam and has a hole for passing the cable therein;
A charged particle beam drawing apparatus comprising:   The charged particle beam drawing apparatus according to claim 1, wherein the deflector includes a plurality of stages of main deflectors and a plurality of stages of sub-deflectors.   4. The charged particle according to claim 1, wherein the block is made of a metal having excellent conductivity and is composed of a single body or a plurality of combinations that can be combined. 5. Beam drawing device. 5. The charged particle beam drawing apparatus according to claim 1, wherein the cable penetrating the block includes at least a conductor and an insulator covering the periphery of the conductor. 6.

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