JP6581520B2 - Charged particle beam lithography system - Google Patents

Description

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

  In a lithography process of a semiconductor element constituting a recording medium such as a flash memory or a CPU (Central Processing Unit), an original pattern formed on the mask is transferred to a wafer serving as a substrate of the semiconductor element. Drawing of the original pattern on the mask is performed by, for example, a charged particle beam drawing apparatus.

  In pattern drawing using a charged particle beam, phenomena such as fogging occur due to the influence of secondary electrons generated by scattering of the charged particle beam incident on the object to be drawn. When fogging occurs, CD (Critical Dimension) accuracy decreases, and the resist is charged, so that an error occurs in the incident position of the electron beam. Thus, various techniques for suppressing the influence of secondary electrons have been proposed (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 10-229041

  In the apparatus disclosed in Patent Document 1, the secondary electrons generated when the electron beam enters the substrate are shielded by the cover, thereby suppressing the secondary electrons from entering the substrate. Thereby, a reduction in drawing accuracy due to fogging is suppressed. However, in this apparatus, the ratio of secondary electrons reflected by the cover is relatively high, and it is considered difficult to sufficiently improve the drawing accuracy.

  The present invention has been made under the circumstances described above, and an object of the present invention is to suppress the influence of secondary electrons from an object to be drawn and improve the pattern drawing accuracy.

In order to solve the above problems, a charged particle beam drawing apparatus according to this embodiment includes a deflection unit that deflects a charged particle beam incident on a drawing target, and a shot region that is defined by the deflection amount of the charged particle beam by the deflection unit. A shield plate formed with an opening through which the aperture is exposed, the aperture of the shield plate being a size of the shot area, a height of the shield plate from the drawing object, and a secondary that scatters from the sample and returns to the sample It is defined based on the distribution of electrons. The radius of the opening of the shielding plate is indicated by the sum of the product of the width of the shot area and the height of the shielding plate from the drawing object and the coefficient.

  According to the present invention, the proportion of secondary electrons that are generated from the drawing object and then return to the drawing object decreases. Therefore, the influence of secondary electrons can be suppressed and the pattern drawing accuracy can be improved.

It is a block diagram of the charged particle beam drawing apparatus concerning this embodiment. It is a top view of a shaping aperture. It is a figure which shows typically the main field prescribed | regulated to a sample, and a subfield. It is a perspective view of a shielding board. It is a figure which shows the cross section of the cover member of a lens-barrel. It is a block diagram of a control apparatus. It is a figure for demonstrating operation | movement of a shielding board. It is a figure for demonstrating operation | movement of a shielding board. It is a figure for demonstrating operation | movement of a shielding board. It is a figure for demonstrating the effect | action of a shielding board. It is a figure for demonstrating the effect | action of a shielding board. It is a figure which shows the modification of a shielding board. It is a figure which shows the modification of a charged particle beam drawing apparatus.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings. In describing the embodiment, an orthogonal coordinate system including an X axis, a Y axis, and a Z axis that are orthogonal to each other is used.

FIG. 1 is a diagram showing a schematic configuration of a charged particle beam drawing apparatus 10 according to the present embodiment. A charged particle beam drawing apparatus 10, for example, a vacuum degree in the environment of about 10 -7 ^Pa, the sample 120 such as a mask or a reticle resist material is coated, a device for drawing a pattern.

  As shown in FIG. 1, the charged particle beam drawing apparatus 10 includes, for example, an irradiation device 20 that irradiates a sample 120 with an electron beam EB, a stage 61 on which the sample 120 is placed, and a shielding plate disposed above the sample 120. 70, a lighting chamber 60 that accommodates a stage 61 and the like, an irradiation apparatus 20, and a control system 100 that controls the stage 61 are provided.

  The irradiation device 20 includes a lens barrel 21 having a longitudinal direction as a vertical axis direction, an electron gun 22 arranged from the upper side to the lower side of the lens barrel 21, deflectors 31 to 34, lenses 41 to 43, and a blanking aperture. 51, and shaping apertures 52 and 53 are provided.

  The lens barrel 21 has a cylindrical casing 21a that is open at the bottom and a lid member 21b that is attached to the casing 21a. The casing 21a is made of, for example, stainless steel and is grounded. The casing 21 a is drawn into the writing chamber 60 from above the writing chamber 60.

  The lid member 21b is also made of stainless steel like the lens barrel. The lid member 21b has an opening 21c through which the electron beam EB passes in the center, and is attached to the casing 21a by, for example, a bolt. By attaching the lid member 21b to the casing 21a, the internal space and the external space of the casing 21a are partitioned.

  The electron gun 22 is disposed inside the lens barrel 21. The electron gun 22 is, for example, a hot cathode type electron gun. The electron gun 22 includes a cathode, a Wehnelt electrode provided so as to surround the cathode, an anode disposed below the cathode, and the like. When a voltage is applied, the electron gun 22 emits an electron beam EB downward. The acceleration voltage of the electron gun 22 is, for example, about 50 kev.

  The deflector 31 is disposed below the electron gun 22. The deflector 31 has a pair of blanking electrodes disposed so as to face each other. The deflector 31 deflects the electron beam EB emitted from the electron gun 22 based on the voltage applied by the blanking amplifier 103 constituting the control system 100.

  The blanking aperture 51 is disposed below the deflector 31. The blanking aperture 51 is a plate-like member provided with an opening through which the electron beam EB passes in the center.

  The above-described deflector 31 receives a binary voltage signal of high level and low level. In the deflector 31, when the voltage signal input to one blanking electrode is at a high level, an electric field is generated between the blanking electrodes, and the electron beam EB is deflected. Thereby, the electron beam EB is blanked by the blanking aperture 51. When the voltage signal is at a low level, the electron beam EB passes through the opening of the blanking aperture 51 without being deflected.

  The lens 41 is an annular lens arranged so as to surround the deflector 31. The lens 41 irradiates the upper surface of the shaping aperture 52 disposed below the blanking aperture 51 with the electron beam EB passing through the deflector 31.

  The shaping aperture 52 is disposed below the blanking aperture 51. In the center of the shaping aperture 52, for example, a rectangular opening is formed. As the electron beam EB passes through the opening of the shaping aperture 52, the shot shape of the electron beam EB is shaped into a rectangle.

  The deflector 32 is disposed below the shaping aperture 52. The deflector 32 has a plurality of pairs of deflecting electrodes arranged to face each other. In FIG. 1, only a pair of deflection electrodes 32a and 32b disposed at a predetermined distance in the X-axis direction are shown. The deflector 32 deflects the electron beam EB that has passed through the shaping aperture 52 two-dimensionally in the X-axis direction and the Y-axis direction in accordance with the voltage applied to the deflection electrode.

  The lens 42 is an annular lens arranged so as to surround the deflector 32. The lens 42 irradiates the upper surface of the shaping aperture 53 with the electron beam EB passing through the deflector 32.

  The shaping aperture 53 is disposed below the deflector 32. FIG. 2 is a plan view of the shaping aperture 53. As shown in FIG. 2, an opening 53 a is formed at the center of the shaping aperture 53. The opening 53a is an octagon composed of two sides parallel to the Y axis, two sides parallel to the X axis, two sides forming an angle of 45 degrees with the X axis, and two sides forming an angle of 135 degrees with the X axis. It has been shaped.

  In the charged particle beam drawing apparatus 10, the electron beam EB is irradiated on desired regions A <b> 1 to A <b> 5 on the upper surface of the shaping aperture 53 by the cooperation of the deflector 32 and the lens 42. When the region A1 is irradiated with the electron beam EB, the spot shape of the electron beam EB is shaped into, for example, a rectangle. In addition, when the electron beam EB is irradiated onto the regions A2 to A5, the spot shape of the electron beam EB is shaped into, for example, a right-angled isosceles triangle.

  As shown in FIG. 1, the deflector 33 is disposed below the shaping aperture 53. The deflector 33 has a plurality of pairs of deflecting electrodes arranged to face each other. FIG. 1 shows only a pair of deflection electrodes 33a and 33b arranged at a predetermined distance in the X-axis direction. The deflector 33 deflects the electron beam EB that has passed through the shaping aperture 53 two-dimensionally in the X-axis direction and the Y-axis direction in accordance with the voltage applied to the deflection electrode.

  The deflector 34 is disposed below the deflector 33. The deflector 34 has a plurality of pairs of deflecting electrodes arranged to face each other. In FIG. 1, only a pair of deflection electrodes 34a and 34b arranged at a predetermined distance in the X-axis direction are shown. The deflector 34 two-dimensionally deflects the electron beam EB that has passed through the deflector 33 in the X-axis direction and the Y-axis direction in accordance with the voltage applied to the deflection electrode.

  The lens 43 is an annular lens disposed so as to surround the deflectors 33 and 34. The lens 42 focuses the electron beam EB passing through the deflectors 33 and 34 on the upper surface of the sample 120.

  In the charged particle beam drawing apparatus 10, the position of the electron beam EB incident on the sample 120 is controlled in two stages by the cooperation of the deflectors 33 and 34 and the lens 43. FIG. 3 is a diagram schematically showing the main field MF and the subfield SF defined on the upper surface of the sample 120. The main field MF is an area defined by the change width of the electron beam EB in the X-axis direction and the Y-axis direction by the deflector 34. The subfield SF is an area defined by the change width of the electron beam EB in the X axis direction and the Y axis direction by the deflector 33. The incident position of the electron beam EB with respect to the sample 120 is controlled by the deflector 34 in the main field MF, and the deflector 33 is controlled in the subfield SF.

  As shown in FIG. 1, the shielding plate 70 is disposed below the lens barrel 21. FIG. 4 is a perspective view of the shielding plate 70. As shown in FIG. 4, the shielding plate 70 is a square member having a thickness of about several hundreds μm to 1 mm. The dimensions of the shielding plate 70 in the X axis direction and the Y axis direction are substantially equal to the dimensions of the sample 120 in the X axis direction and the Y axis direction. The shielding plate 70 is made of ceramic, and a metal thin film is formed on the surface thereof. A rectangular recess 71 that is recessed downward is formed at the center of the shielding plate 70. A circular opening 72 penetrating in the X-axis direction is formed on the bottom surface of the recess 71. The opening 72 is shaped to be slightly larger than the circle inscribed by the main field MF shown in FIG. A cylindrical shaft 73 having a longitudinal direction as the Z-axis direction is fixed to the center of the outer edge portion on the −X side of the shielding plate 70.

  FIG. 5 is a view showing a cross section of the lid member 21 b of the lens barrel 21. As shown in FIG. 5, the shielding plate 70 is arranged in a horizontal state by being supported by the drive mechanism 80 with the shaft 73 passing through the opening 21 d provided in the lid member 21 b. . Further, the shielding plate 70 is grounded via a shaft 73.

  The drive mechanism 80 includes a motor, a gear, and the like, and supports the shaft 73 of the shielding plate 70 so as to be rotatable around the vertical axis.

  Returning to FIG. 1, the writing chamber 60 is a rectangular parallelepiped hollow member, and a circular opening is formed on the upper surface. The lens barrel 21 of the irradiation apparatus 20 described above is inserted into an opening formed on the upper surface of the writing chamber 60.

  The stage 61 is disposed inside the writing chamber 60. The stage 61 moves at least in the horizontal plane while holding the sample 120 on which the pattern is drawn substantially horizontally. On the upper surface of the stage 61, a mirror Mx whose longitudinal direction is the Y-axis direction is fixed along the outer edge on the −X side, and a mirror My whose longitudinal direction is the X-axis direction is provided along the outer edge on the + Y side. Yes. The position of the stage 61 in the horizontal plane is detected with reference to the mirrors Mx and My by an optical sensor or the like.

  As shown in FIG. 5, the stage 61 positions the sample 120 substantially horizontally so that the upper surface of the sample 120 is located at a distance d from the lower surface of the lid member 21 b of the lens barrel 21. The shielding plate 70 is supported so that the height from the upper surface of the sample 120 is h. The value of d is approximately 10 mm, and the value of h is approximately 1 mm.

  Returning to FIG. 1, the control system 100 is a system for controlling the irradiation apparatus 20, the stage 61, and the like. The control system 100 includes a control device 101, a high voltage power supply device 102, a blanking amplifier 103, a lens driving device 104, a deflection amplifier 105, a shielding plate driving device 106, and a stage driving device 107.

  FIG. 6 is a block diagram of the control device 101. As shown in FIG. 6, the control device 101 includes a CPU (Central Processing Unit) 101a, a main storage unit 101b, an auxiliary storage unit 101c, an input unit 101d, a display unit 101e, an interface unit 101f, and a system that connects the above-described units. A computer having a bus 101g.

  The CPU 101a reads and executes the program stored in the auxiliary storage unit 101c. And the apparatus which comprises the control system 100 is controlled according to a program.

  The main storage unit 101b has a volatile memory such as a RAM (Random Access Memory). The main storage unit 101b is used as a work area for the CPU 101a.

  The auxiliary storage unit 101c includes a nonvolatile memory such as a ROM (Read Only Memory), a magnetic disk, and a semiconductor memory. The auxiliary storage unit 101c stores a program executed by the CPU 101a, drawing data indicating a pattern drawn on the sample 120, and the like. Further, information including processing results by the CPU 101a is sequentially stored.

  The input unit 101d has a keyboard and a pointing device such as a mouse. The user instruction is input via the input unit 101d and is notified to the CPU 101a via the system bus 101g.

  The display unit 101e has a display unit such as an LCD (Liquid Crystal Display). The display unit 101e displays, for example, information on the status of the charged particle beam drawing apparatus 10 and a drawing pattern.

  The interface unit 101f includes a LAN interface, a serial interface, a parallel interface, an analog interface, and the like. The high-voltage power supply device 102, the blanking amplifier 103, the lens driving device 104, the deflection amplifier 105, the shielding plate driving device 106, and the stage driving device 107 are connected to the control device 101 via the interface unit 101f.

  The control device 101 configured as described above comprehensively controls the high-voltage power supply device 102, the blanking amplifier 103, the lens driving device 104, the deflection amplifier 105, the shielding plate driving device 106, and the stage driving device 107.

  Returning to FIG. 1, the high voltage power supply apparatus 102 applies a voltage to the electron gun 22 based on an instruction from the control apparatus 101. Thereby, an electron beam EB is emitted from the electron gun 22 toward the sample 120.

  The blanking amplifier 103 generates a blanking signal based on an instruction from the control device 101. Then, the generated blanking signal is output to the deflector 31. For example, the blanking signal is a binary signal having a high level of 500 mV and a low level of 0V. When the blanking signal output to the deflector 31 is at a high level, the electron beam EB is blanked.

  The lens driving device 104 controls the power (refractive power) of the lenses 41 and 42 with respect to the electron beam EB based on an instruction from the control device 101 and irradiates the upper surfaces of the shaping apertures 52 and 53 with the electron beam EB. Further, the power of the lens 43 is controlled to focus the electron beam EB on the upper surface of the sample 120.

  The deflection amplifier 105 generates a voltage signal based on an instruction from the control device 101 and outputs the voltage signal to the deflection electrodes constituting the deflectors 32 to 34. A potential difference is generated between the deflection electrodes constituting the deflectors 32 to 34. Thereby, the electron beam EB passing through the deflectors 32 to 34 is two-dimensionally deflected in the X-axis direction and the Y-axis direction by an amount corresponding to the potential difference.

  The stage driving device 107 drives the stage 61 based on an instruction from the control device 101 to move or position the sample 120.

  The shielding plate driving device 106 rotates the shielding plate 70 based on an instruction from the control device 101. For example, when the stage 61 on which the sample 120 is placed is positioned below the lens barrel 21, the shielding plate driving device 106 rotates the shielding plate 70 around the shaft 73 via the driving mechanism 80. 7 and is retracted from below the lens barrel 21 as shown in FIG. As a result, as shown in FIG. 8, the stage 61 can be moved to the lower side of the lens barrel 21 without being interfered with the shielding plate 70 and positioned relative to the lens barrel 21. When the positioning of the stage 61 is completed, the shielding plate driving device 106 rotates the shielding plate 70 around the shaft 73 via the drive mechanism 80, and as shown in FIG. Is returned below the lens barrel 21.

  Similarly, when the stage 61 on which the sample 120 is placed is moved from below the lens barrel 21, the shielding plate driving device 106 moves the shielding plate 70 around the shaft 73 via the driving mechanism 80. Rotate and retreat from the lower side of the lens barrel 21 as shown in FIG. As a result, the stage 61 can be moved from below the lens barrel 21 without interfering with the shielding plate 70.

  Pattern drawing by the charged particle beam drawing apparatus 10 described above is performed by the CPU 101a configuring the control apparatus 101 controlling the above-described units based on a program stored in the auxiliary storage unit 101c.

  For example, in order to draw a pattern on the sample 120, the CPU 101 a drives the stage 61 via the stage driving device 107 shown in FIG. 1 and positions the sample 120 below the irradiation device 20.

  Next, the CPU 101 a drives the high voltage power supply device 102 to apply a voltage to the electron gun 22. Thereby, an electron beam EB is emitted from the electron gun 22.

  When the electron beam EB is emitted from the electron gun 22, the CPU 101 a controls the lens 41 via the lens driving device 104 to irradiate the upper surface of the shaping aperture 52 with the electron beam EB. When the shaping aperture 52 is irradiated with the electron beam EB, the electron beam EB whose spot shape is shaped into a rectangle is emitted from the opening of the shaping aperture 52 toward the deflector 32.

  The CPU 101a controls the deflector 32 via the deflection amplifier 105 and the lens 42 via the lens driving device 104 to convert the electron beam EB shaped by the shaping aperture 52 into the shaping aperture shown in FIG. Irradiate any one of the regions A1 to A5 on the upper surface of 53. By irradiating one of the regions A1 to A5 of the shaping aperture 53 with the electron beam EB, the spot shape of the electron beam EB is shaped into a shape according to the regions A1 to A5. The electron beam EB whose spot shape has been shaped by the shaping aperture 53 is emitted toward the deflectors 33 and 34.

  The CPU 101 a controls the deflectors 33 and 34 via the deflection amplifier 105 and also controls the lens 43 via the lens driving device 104, and a desired position on the surface of the sample 120 held on the stage 61 by the electron beam EB. Focus on.

  In parallel with the above operation, the CPU 101a controls the deflector 31 via the blanking amplifier 103 based on the drawing data. Thereby, the electron beam EB is deflected at a timing according to the drawing data, and blanking is executed intermittently.

  In the charged particle beam drawing apparatus 10, the pattern is drawn on the sample 120 by driving the high-voltage power supply apparatus 102, the blanking amplifier 103, the lens driving apparatus 104, and the deflection amplifier 105 by the CPU 101 a as described above.

  FIG. 10 is a diagram schematically illustrating the behavior of secondary electrons scattered from the sample 120. When a pattern is drawn on the sample 120 as described above, the electron beam EB is incident on the surface of the sample 120, and secondary electrons are scattered from where the electron beam EB is incident. Secondary electrons from the sample 120 travel while spreading radially upward. Then, it is reflected by the lid member 21 b of the lens barrel 21 and enters the sample 120.

  In the charged particle beam drawing apparatus 10, a shielding plate 70 is provided between the lid member 21 b of the lens barrel 21 and the sample 120. For this reason, as shown in FIG. 11, secondary electrons from the sample 120 travel through the openings 72 of the shielding plate 70 while spreading radially upward. The secondary electrons are reflected by the lid member 21 b of the lens barrel 21 and then shielded by the shielding plate 70. For this reason, the influence of the fogging etc. which are generated by the secondary electrons scattered from the sample 120 can be suppressed.

  A region that is greatly affected by fogging is a circular region centered on the incident position of the electron beam EB. Hereinafter, for convenience of explanation, it is simply referred to as a circular region. The radius r1 of the circular region is expressed by the following equation (1). As can be seen with reference to FIG. 10 or FIG. 11, d is the distance from the sample 120 to the lens barrel 21. Α is an angle formed by the reflection angle of the electron beam EB, that is, the secondary electron emission path and the normal line of the upper surface of the sample 120.

  r1 = 2d · sin (α) (1)

The distribution of secondary electrons in the circular region with the radius r1 is exp (− (r1 ² / σF ² )). Note that σF is expressed by the following equation (2). Further, σα is a solid angle of the circular region and satisfies the relationship of the following expression (3).

σF = 2d · sin (σα) (2)
σα = sin ⁻¹ (σF / 2d) (3)

  When secondary electrons generated when the electron beam EB is incident on the main field MF of the sample 120 are considered, secondary electrons from other than the circular region defined by σα may be handled as zero. Absent. Therefore, the opening 72 of the shielding plate 70 is a circle having a radius r2 represented by the following equation (4), where D is the width of the main field MF and h is the height from the sample 120 to the shielding plate 70. preferable.

  r2 = D + h · tan (σα) (4)

  When the opening 72 of the shielding plate 70 is smaller than the circle having the radius r2, secondary electrons from the sample 120 are reflected by the lower surface of the shielding plate 70 and enter the sample 120, causing fogging or the like to the sample 120. Because it will end up. Further, when the opening 72 of the shielding plate 70 is larger than the circle having the radius r2, secondary electrons from the sample 120 are reflected by the lens barrel 21 after passing through the opening 72 and returned to the sample 120. This is because a phenomenon such as fogging occurs in the sample 120.

  In the charged particle beam drawing apparatus 10, the size of the main field MF is a small square having a side of about 0.5 μm. For this reason, Formula (4) can be approximated as the following Formula (5).

  r2 = D + h · σα (5)

  In the charged particle beam drawing apparatus 10, the value of d is approximately 10 mm, and the value of h is approximately 1 mm. The value of σα is approximately 0.1 rad, and the width of D is 50 μm. Therefore, the radius r2 is approximately 181 μm. Therefore, the opening 72 provided in the shielding plate 70 is desirably a circle having a radius of about 181 μm.

  As described above, in the present embodiment, the occurrence of phenomena such as fogging caused by secondary electrons scattered from the sample 120 is suppressed. Therefore, the pattern drawing accuracy can be improved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited by the said embodiment. For example, in the above embodiment, the case where the value of the height h of the shielding plate 70 with respect to the upper surface of the sample 120 is 1 mm and the value of the distance d between the sample 120 and the lens barrel 21 is 10 mm has been described. The present embodiment is not limited to this. For example, when the value of h is other than 1 mm and the value of d is other than 10 mm, the radius of the opening 72 of the shielding plate 70 can be defined based on the above formula (5).

  In the said embodiment, the thickness of the shielding board 70 shall be about several hundred micrometers-1 mm. This embodiment is not limited to this. For example, when the thickness of the shielding plate 70 is large, the inner wall surface of the opening 72 is arranged so that the shielding plate 70 does not interfere with the path of secondary electrons from the sample 120. 12 may be tapered as shown in FIG.

  In the above embodiment, the shielding plate 70 is made of ceramic whose surface is coated with a metal thin film. However, the material of the shielding plate 70 may be a metal.

  In the above embodiment, the case where the shielding plate 70 rotates about the shaft 73 has been described. For example, as shown in FIG. 13, the drive mechanism 80 that supports the shielding plate 70 may be lifted and lowered together with the shielding plate 70 by the lifting mechanism 81. In this case, the relative position of the shielding plate 70 with respect to the sample 120 can be adjusted according to the type and thickness of the sample 120. Further, the retracting of the shielding plate 70 is facilitated when the stage 61 is pulled below the barrel 21.

  In the above embodiment, the charged particle beam drawing apparatus that draws a pattern using an electron beam has been described. For example, the charged particle beam drawing apparatus may draw a pattern using a beam other than an electron beam such as an ion beam.

  In the above embodiment, the case where the charged particle beam drawing apparatus 10 includes the drive mechanism 80 that rotates the shielding plate 70 has been described. However, the charged particle beam drawing apparatus 10 may not include the driving mechanism 80 when the stage 61 can be drawn below the lens barrel 21 without causing the stage 61 to interfere with the shielding plate 70. .

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof 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 10 Charged particle beam drawing apparatus 20 Irradiation apparatus 21 Lens barrel 21a Casing 21b Cover member 21c, 21d Opening 22 Electron gun 31-34 Deflector 32a, 32b, 33a, 33b, 34a, 34b Deflection electrode 41-43 Lens 51 Blanking aperture 52, 53 Shaping aperture 53a Opening 60 Writing chamber 61 Stage 70 Shielding plate 71 Recessed part 72 Opening 73 Shaft 80 Drive mechanism 81 Lifting mechanism 100 Control system 101 Controller 101a CPU
101b Main storage unit 101c Auxiliary storage unit 101d Input unit 101e Display unit 101f Interface unit 101g System bus 102 High voltage power supply device 103 Blanking amplifier 104 Lens drive device 105 Deflection amplifier 106 Shield plate drive device 107 Stage drive device 120 Sample A1 to A5 area EB Electron beam MF Main field SF Subfield.
Mx, My mirror

Claims (4)

Deflecting means for deflecting a charged particle beam incident on a drawing object;
A shielding plate in which an opening through which a shot region defined by the deflection amount of the charged particle beam by the deflecting unit is exposed is formed;
With
The opening of the shielding plate, the size of the shot area, the the height of the shielding plate from the drawing object, and scattered from the sample is defined based on the distribution of the secondary electrons back to the sample, wherein opening of the radius, and the width of the shot area, the drawing the shielding plate height and coefficient of sum-of-products at the indicated Ru charged particle beam drawing apparatus of the subject. The charged particle beam drawing apparatus according to claim 1, wherein the shielding plate has conductivity and is grounded. The shield plate, a charged particle beam drawing apparatus according to claim 1 or 2 comprising a moving means for moving from above the drawing object. The charged particle beam drawing apparatus according to claim 3 , wherein the moving unit rotates the shielding plate around a rotation axis.

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