JP2014075520A - Charged particle beam drawing device - Google Patents

Abstract

Provided is a charged particle beam drawing apparatus capable of suppressing a reduction in drawing accuracy due to atmospheric pressure fluctuation while suppressing complication and enlargement of the apparatus.
A charged particle beam drawing apparatus includes an optical barrel 2b incorporating a charged particle optical system, a vacuum vessel 2a having an opening 2a1 formed on an upper surface, and an optical barrel 2b fixed to the opening 2a1. A lid 34 for closing and the inside of the vacuum vessel 2a is divided into a first internal space K1 on the upper surface side of the vacuum vessel 2a and a second internal space K2 on the bottom side of the vacuum vessel 2a. A base body 31 that is divided and formed with a through-hole 31a, a plurality of support members 35 that are fixed to the base body 31 and provided in the first internal space K1 of the vacuum vessel 2a and support the lid body 34; An expandable / contractible member 36 that connects the container 2a and the lid 34 and seals the vacuum container 2a is provided.
[Selection] Figure 2

Description

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

  With the recent high integration and large capacity of large scale integrated circuits (LSIs), circuit line widths required for semiconductor devices are becoming increasingly smaller. In order to form a desired circuit pattern on a semiconductor device, a lithography technique is used. In this lithography technique, pattern transfer using an original pattern called a mask (reticle) is performed. In order to manufacture a high-accuracy mask used for this pattern transfer, a charged particle beam drawing apparatus having an excellent resolution is used.

  As an example of this charged particle beam drawing apparatus, while moving a stage on which a sample such as a mask or a blank is moved, the charged particle beam is deflected and irradiated to a predetermined position of the sample on the stage, and the sample on the stage is irradiated. A charged particle beam drawing apparatus for drawing a pattern has been developed. In this charged particle beam drawing apparatus, an optical barrel is mounted on a vacuum container serving as a sample chamber. This optical column contains a charged particle optical system for irradiating a charged particle beam.

  In such a charged particle beam drawing apparatus, when the vacuum container is brought into a vacuum state by reducing the pressure, the vacuum container is deformed minutely (for example, about several tens of μm) due to the atmospheric pressure. The lens barrel will tilt. The inclination of the optical column affects the trajectory of the charged particle beam. In particular, the atmospheric pressure fluctuates according to the passage of high and low atmospheric pressure (change in weather), so this atmospheric pressure variation changes the amount of deformation of the vacuum vessel, that is, the tilt of the optical column, and the charged particle beam trajectory changes. Change. Therefore, the stability of the irradiation position is lowered due to the atmospheric pressure fluctuation, and as a result, the drawing accuracy is lowered.

  Here, in order to prevent deterioration of the position accuracy of the stage, the sample chamber which is a vacuum container is formed in a double sealed container structure of the inner container and the outer container, and the space between the inner container and the outer container is constant. There has been proposed a charged particle beam drawing apparatus that maintains the pressure of (see, for example, Patent Document 1). Further, in order to improve the irradiation accuracy of the charged particle beam and improve the maintainability and the assembly reproducibility, a charged particle beam device having a column support that supports the optical barrel across the vacuum vessel has been proposed. (For example, refer to Patent Document 2). Furthermore, in order to suppress the vibration of the optical barrel when moving the stage, an electron beam drawing apparatus having a gantry for supporting the optical barrel on a sample chamber which is a vacuum vessel has been proposed (for example, Patent Document 3). reference).

JP 2003-17394 A JP 2003-318080 A JP 2002-260566 A

  However, in the charged particle beam drawing apparatus that maintains the space between the inner container and the outer container at a constant pressure as described above, a control mechanism for keeping the pressure constant is required, which complicates the apparatus. End up. In addition, a charged particle beam drawing apparatus having a column support outside the vacuum vessel or an electron beam drawing apparatus having a gantry outside the sample chamber will increase the size of the apparatus. For this reason, it is desired to suppress a reduction in drawing accuracy due to atmospheric pressure fluctuations while suppressing the complexity and size of the apparatus.

  The problem to be solved by the present invention is to provide a charged particle beam drawing apparatus capable of suppressing a reduction in drawing accuracy due to a change in atmospheric pressure while suppressing an increase in complexity and size of the apparatus.

  In a charged particle beam drawing apparatus according to an embodiment of the present invention, an optical lens tube incorporating a charged particle optical system, a vacuum container having an opening formed on an upper surface, and the optical lens tube are fixed to block the opening. The inside of the vacuum vessel is divided into a first internal space on the upper surface side of the vacuum vessel and a second internal space on the bottom side of the vacuum vessel, and a through hole is formed. A base body, fixed in the base body, provided in the first internal space of the vacuum vessel, and extendable to seal the vacuum vessel by connecting the vacuum vessel and the lid with a plurality of support members that support the lid. An elastic member.

  The charged particle beam drawing apparatus preferably further includes a laser interferometer fixed to the support member.

  In the above charged particle beam drawing apparatus, it is desirable that the expansion / contraction member is fixed to the lid by welding and is fixed to the vacuum vessel by a fixing member.

  In the charged particle beam drawing apparatus, the expansion / contraction member has a bonding portion bonded to the vacuum container by the fixing member, and the bonding portion is a material having a lower concentration of phosphorus and sulfur than other portions of the expansion / contraction member. It is desirable to be formed by.

In the charged particle beam drawing apparatus, the base body and the plurality of support members are preferably formed of a material having a linear expansion coefficient of 2 × 10 ⁻⁶ / K or less at room temperature.

  ADVANTAGE OF THE INVENTION According to this invention, the fall of the drawing precision by atmospheric pressure fluctuation can be suppressed, suppressing complication and enlargement of an apparatus.

It is a figure which shows schematic structure of the charged particle beam drawing apparatus which concerns on embodiment. It is sectional drawing which shows schematic structure of the drawing part with which the charged particle beam drawing apparatus shown in FIG. 1 is provided. It is a top view which shows the cover body and several support member with which the drawing part shown in FIG. 2 is provided. It is sectional drawing which expands and shows the expansion-contraction member with which the drawing part shown in FIG. 2 is provided, and its periphery. It is sectional drawing which shows the vacuum state of the drawing part shown in FIG.

  An embodiment will be described with reference to the drawings.

  As shown in FIG. 1, the charged particle beam drawing apparatus 1 according to the embodiment includes a drawing unit 2 that performs drawing using a charged particle beam, and a control unit 3 that controls the drawing unit 2. The charged particle beam drawing apparatus 1 is an example of a variable shaping type drawing apparatus using, for example, an electron beam as a charged particle beam. The charged particle beam is not limited to the electron beam, and may be another charged particle beam such as an ion beam.

  The drawing unit 2 includes a vacuum container 2a serving as a sample chamber (drawing chamber) for storing a sample W to be drawn, and an optical barrel 2b connected to the vacuum container 2a. The optical barrel 2b is provided on the upper surface of the vacuum vessel 2a, and shapes and deflects an electron beam by a charged particle optical system (electron optical system) and irradiates the sample W in the vacuum vessel 2a. is there. At this time, the inside of both the vacuum vessel 2a and the optical barrel 2b is depressurized to be in a vacuum state.

  A stage 11 that supports the sample W is provided in the vacuum vessel 2a. The stage 11 is formed to be movable by a moving mechanism 12 in an X-axis direction and a Y-axis direction (hereinafter simply referred to as X direction and Y direction) that are orthogonal to each other in a horizontal plane. For example, a sample W such as a mask or a blank is placed on the placement surface of the stage 11. Further, a laser interferometer 13 is provided inside the vacuum vessel 2a, and this laser interferometer 13 is a measuring instrument that measures the separation distance between itself and the stage 11, that is, the mirror 11a on the stage 11. Furthermore, a drive unit 14 is provided on the outer surface of the vacuum vessel 2 a, and this drive unit 14 drives a moving mechanism 12 that moves the stage 11. The mirror 11a, the laser interferometer 13 and the drive unit 14 are set as one set, and two sets are provided for the X direction and the Y direction.

  In the optical barrel 2b, an emission part 21 such as an electron gun for emitting an electron beam B, an illumination lens 22 for condensing the electron beam B, a first shaping aperture 23 for beam shaping, and a projection purpose The projection lens 24, the beam shaping shaping deflector 25, the beam shaping second shaping aperture 26, the objective lens 27 that focuses the beam on the sample W, and the beam shot position with respect to the sample W. A sub-deflector 28 and a main deflector 29 are arranged. Each of these units 21 to 29 functions as a charged particle optical system.

  In such a drawing unit 2, the electron beam B is emitted from the emission unit 21, and is irradiated to the first shaping aperture 23 by the illumination lens 22. The first shaping aperture 23 has, for example, a rectangular opening. Thereby, when the electron beam B passes through the first shaping aperture 23, the cross-sectional shape of the electron beam is shaped into a rectangular shape and projected onto the second shaping aperture 26 by the projection lens 24. The projection position can be deflected by the shaping deflector 25, and the shape and size of the electron beam B can be controlled by changing the projection position. Thereafter, the electron beam B that has passed through the second shaping aperture 26 is irradiated with the focus of the electron beam B being adjusted to the sample W on the stage 11 by the objective lens 27. At this time, the shot position of the electron beam B with respect to the sample W on the stage 11 is deflected by the sub deflector 28 and the main deflector 29.

  The control unit 3 includes a drawing data storage unit 3 a that stores drawing data, a shot data generation unit 3 b that processes the drawing data to generate shot data, and a drawing control unit 3 c that controls the drawing unit 2. Yes. The shot data generation unit 3b and the drawing control unit 3c may be configured by hardware such as an electric circuit, may be configured by software such as a program that executes each function, or may be You may comprise by the combination of both.

  The drawing data storage unit 3 a is a storage unit that stores drawing data for drawing a pattern on the sample W. The drawing data is converted into a format for the charged particle beam drawing apparatus 1 so that design data (layout data) created by a semiconductor integrated circuit designer can be input to the charged particle beam drawing apparatus 1. The data is input from an external device to the drawing data storage unit 3a and stored. For example, a magnetic disk device, a semiconductor disk device (flash memory), or the like can be used as the drawing data storage unit 3a.

  The design data described above usually includes a large number of minute patterns (such as graphics), and the amount of data is considerably large. If this design data is converted into another format as it is, the data amount after conversion further increases. For this reason, in the drawing data, the amount of data is reduced by a method such as data hierarchization or pattern array display. Such drawing data is data that defines a drawing pattern of a chip area or a drawing pattern of a virtual chip area that is virtually merged into a plurality of chip areas that have the same drawing conditions. .

  The shot data generation unit 3b divides the drawing pattern defined by the drawing data into a plurality of stripe regions (stripes) (a longitudinal direction is the X direction and a short direction is the Y direction), and Each stripe region is divided into a large number of matrix-like subregions. In addition, the shot data generation unit 3b determines the shape, size, position, and the like of the figure in each sub-area, and if the figure cannot be drawn in one shot, a plurality of drawables Is divided into partial areas, and shot data is generated. The length of the stripe region in the short direction (Y direction) is set to a length capable of deflecting the electron beam B by main deflection.

  The drawing controller 3c positions the electron beam B in each sub-region by the main deflector 29 while moving the stage 11 in the longitudinal direction (X direction) of the stripe region by the moving mechanism 12 when drawing the drawing pattern. Then, the sub-deflector 28 takes a shot at a predetermined position in the sub area and draws a figure. After that, when drawing of one stripe region is completed, the stage 11 is moved stepwise in the Y direction, and then the next stripe region is drawn. This is repeated, and drawing by the electron beam B is performed on the entire drawing region of the sample W. Do. During drawing, since the stage 11 continuously moves in one direction, the drawing origin of the sub-region is tracked by the main deflector 29 so that the drawing origin follows the movement of the stage 11. .

  Thus, the irradiation position of the electron beam B is determined while following the stage 11 which is deflected by the sub deflector 28 and the main deflector 29 and continuously moves. The drawing time can be shortened by continuously moving the stage 11 in the X direction and making the shot position of the electron beam B follow the movement of the stage 11. However, in this embodiment, the stage 11 is continuously moved in the X direction. However, the present invention is not limited to this. For example, one stage is drawn while the stage 11 is stopped, and the next When moving to the sub-region, a step-and-repeat drawing method that does not perform drawing may be used.

  In such drawing with the electron beam B, the relative distance information regarding the relative distance to the stage 11 measured by the laser interferometer 13 is not only the control (feedback control) related to the movement of the stage 11 by the moving mechanism 12 but also the sub-deflection. It is also used for control of the instrument 28 and the main deflector 29, that is, control of the irradiation position (drawing control). For this reason, the measurement result by the laser interferometer 13 directly affects the drawing accuracy.

  Next, the vacuum vessel 2a included in the drawing unit 2 will be described in detail with reference to FIGS.

  As shown in FIG. 2, the vacuum container 2 a has an opening 2 a 1 into which the optical barrel 2 b is inserted on the upper surface, and is formed by the first housing 32 and the second housing 33 with the base body 31 therebetween. It is configured. In the first housing 32, a lid 34 to which the optical barrel 2 b is fixed, a plurality of support members 35 that support the lid 34, and an expansion / contraction that connects the first housing 32 and the lid 34. A member 36 and a support base 37 that supports the stage 11 and the moving mechanism 12 are provided.

  The base body 31 is provided in the vacuum vessel 2a, and separates the internal space of the vacuum vessel 2a into a first internal space K1 on the upper surface side of the vacuum vessel 2a and a second internal space K2 on the bottom surface side of the vacuum vessel 2a. Shaped member. The base body 31 has a first surface M1 (front surface) to which each support member 35 is fixed and a second surface M2 (back surface) that is the opposite surface of the first surface M1. A through hole 31 a that connects the first internal space K <b> 1 and the second internal space K <b> 2 is formed in the approximate center of the base body 31. The first internal space K1 and the second internal space K2 only need to be connected by the through hole 31a, and the shape of the through hole 31a is not particularly limited. For example, as the through hole 31a, a through hole (notched portion) formed by notching the end portion of the base body 31 can be used.

  The first housing 32 is formed on the first surface M1 of the base body 31 so as to incorporate the stage 11, the moving mechanism 12, the entire support member 35, the support base 37, and the like. The first housing 32 includes a side wall 32a provided on the first surface M1 of the base body 31, and an upper surface wall 32b having an opening 2a1. The upper flange portion of the side wall 32a and the outer peripheral end of the upper surface wall 32b are fixed by a fixing member (not shown) such as a screw so that the first housing 32 is sealed. Further, the lower flange portion of the side wall 32a is fixed to the first surface M1 of the base body 31 by a fixing member (not shown) such as a screw.

  The second housing 33 is formed on the second surface M2 of the base body 31 so as to be separated from the base body 31 and have a space therebetween. The second housing 33 includes a side wall 33a provided on the second surface M2 of the base body 31, and a bottom wall 33b continuous to the side wall 33a. A portion of the side wall 33a is fixed to the second surface M2 of the base body 31 by a fixing member (not shown) such as a screw.

  The lid 34 is a member for fixing the optical barrel 2b and closing the opening 2a1 of the vacuum vessel 2a. The lid 34 is formed in a shape having a through hole 34a into which the optical barrel 2b is fitted, for example, an annular shape (see FIG. 3). The lid 34 is positioned so as to close the opening 2a1 of the vacuum vessel 2a, and is fixed to each support member 35 by a fixing member (not shown) such as a screw.

  Each support member 35 is a member that is fixed to the first surface M1 of the base body 31 and is provided in the first internal space K1 of the vacuum vessel 2a, and supports the lid body 34. These support members 35 are disposed so as to surround the stage 11, the moving mechanism 12, the support base 37, and the like, and are fixed to the first surface M <b> 1 of the base body 31 with fixing members (not shown) such as screws. The support member 35 is formed so as to have a crank shape by bending both end portions of the plate material in opposite directions. Two such supporting members 35 adjacent to each other are provided with laser interferometers 13 for the X direction or the Y direction in accordance with the mirror 11a on the stage 11 for laser beam passage. The window 35a is formed.

  Here, as shown in FIG. 3, four support members 35 are arranged radially about the central axis of the lid 34, and the lid 34 is supported by four-point support. However, the present invention is not limited to this. For example, the number of support members 35 may be three or two, and the lid 34 may be supported by three-point support or two-point support, and the number of supports is limited. It is not something.

  Returning to FIG. 2, the expandable member 36 is a stretchable member that connects the first housing 32 and the lid 34 of the vacuum vessel 2 a to seal the vacuum vessel 2 a. The elastic member 36 is formed in an annular shape in accordance with the shape of the lid body 34. Since the expansion / contraction member 36 is a member that can expand and contract, even if the vacuum vessel 2a is deformed by atmospheric pressure, it expands and contracts so as to absorb the deformation. The extendable member 36 is a member that can withstand the vacuum pressure and can maintain the sealed state of the vacuum vessel 2a. As the elastic member 36, for example, a bellows member or the like can be used.

  The support base 37 is a member that is provided on the first surface M <b> 1 of the base body 31 and supports the stage 11 and the moving mechanism 12. The support base 37 is provided on the first surface M1 of the base body 31 so as to straddle the through-hole 31a of the base body 31 without blocking it.

  Next, the telescopic member 36 will be described in detail with reference to FIG.

  As shown in FIG. 4, one end of the expansion / contraction member 36 is fixed to the outer end of the lid 34 by welding, and the other end is fixed to the upper surface wall 32 b of the first housing 32 by the fixing member 41. Has been. As the fixing member 41, for example, a screw or the like can be used. A sealing O-ring (O-ring) 42 is provided between the joint portion 36a, which is the tip of the elastic member 36 on the upper surface wall 32b side, and the upper surface wall 32b. The O-ring 42 is located closer to the inner space of the first housing 32 than the fixing member 41 in a state where the expansion / contraction member 36 is fixed. The joining portion 36 a is a portion joined to the upper surface wall 32 b of the first housing 32 by the fixing member 41, and has an annular recess 36 a 1 that accommodates the O-ring 42.

  According to such a joining structure of the stretchable member 36, the stretchable member 36 may be joined to the top wall 32 b of the first housing 32 by the fixing member 41, so that the stretchable member 36 is welded to the top surface of the first housing 32. Compared to the case of joining to the wall 32b (welding at this time is difficult), the assembling work of the apparatus becomes easier, so that workability can be improved.

  The vacuum state (depressurized state) of the vacuum container 2a configured as described above will be described in detail with reference to FIG.

  The vacuum vessel 2a and the optical barrel 2b are depressurized to a predetermined degree of vacuum before drawing starts. Thereby, the inside of both the vacuum vessel 2a and the optical barrel 2b is evacuated. At this time, as shown in FIG. 5, the vacuum vessel 2a is deformed toward the inside by the atmospheric pressure. Specifically, the side wall 32a and the top wall 32b of the first housing 32 of the vacuum vessel 2a are deformed minutely (for example, about several tens of μm) so as to bend inward, and similarly, The bottom wall 33b is deformed minutely (for example, about several tens of μm) so as to bend inside. When the vacuum state of the vacuum vessel 2a and the optical barrel 2b is released, the vacuum vessel 2a returns to its original shape (see FIG. 2).

  Since the deformation of the side wall 32a and the upper surface wall 32b due to the atmospheric pressure is absorbed by the expansion / contraction member 36 being contracted, the inclination of the optical barrel 2b fixed to the lid 34 is not affected. Furthermore, only the vacuum pressure is applied to each support member 35 present in the first internal space K1, and these support members 35 are not affected by the external atmospheric pressure, so that they are not deformed. In addition, only the vacuum pressure is applied to the first surface M1 and the second surface M2 (both front and back surfaces) of the base body 31, and the base body 31 is not affected by the external atmospheric pressure, so that it does not deform. Thereby, even if the atmospheric pressure fluctuates, the support members 35 that support the optical barrel 2b and the base body 31 that supports the support members 35 are not deformed. It is possible to suppress the change in the tilt amount of the cylinder 2b, that is, the trajectory of the charged particle beam. For this reason, it can suppress that stability of an irradiation position, ie, a drawing precision, falls by atmospheric pressure fluctuation.

  As described above, according to the embodiment, the base body 31 that partitions the inside of the vacuum vessel 2a into the first internal space K1 and the second internal space K2 is provided, and the optical barrel 2b is fixed. A plurality of support members 35 that support the lid 34 are provided in the first internal space K1, and further, an elastic member 36 that connects the vacuum vessel 2a and the lid 34 and seals the vacuum vessel 2a is provided, thereby providing a vacuum. The base body 31 and the support members 35 for supporting the container 2a are prevented from being deformed by the influence of atmospheric pressure. As a result, it is possible to suppress the tilt of the optical barrel 2b due to the influence of the atmospheric pressure, so that the tilt amount of the optical barrel 2b, that is, the trajectory of the charged particle beam changes due to the atmospheric pressure fluctuation. As a result, a reduction in drawing accuracy due to atmospheric pressure fluctuations can be suppressed. In addition, since it is only necessary to provide the base body 31 and the support members 35 in the vacuum vessel 2a, the apparatus can be prevented from becoming complicated and large.

  Normally, the laser interferometer 13 is provided on the outer surface of the vacuum vessel 2a. In this case, the optical path of the laser light of the laser interferometer 13 is inclined due to the deformation of the vacuum vessel 2a due to atmospheric pressure. For this reason, the measurement accuracy of the laser interferometer 13 is lowered, and as a result, the drawing accuracy is lowered. However, by providing the laser interferometer 13 on the support member 35 as described above, the support member 35 is not deformed by the influence of atmospheric pressure, so that the optical path of the laser light of the laser interferometer 13 does not tilt. As a result, it is possible to prevent the measurement accuracy of the laser interferometer 13 from being lowered, and thus it is possible to suppress a reduction in drawing accuracy.

Here, it is desirable to use a low thermal expansion material as a material for the base body 31, the lid body 34, each support member 35, and the like. Specifically, it is desirable to form the base body 31, the lid body 34, the support members 35, etc. with a material having a linear expansion coefficient of about 2 × 10 ⁻⁶ / K or less near room temperature. For example, as the low thermal expansion material, invar (Fe-36% Ni) which is a low thermal expansion alloy can be used. The thermal expansion coefficient of this invar is about 1.2 × 10 ⁻⁶ / K near room temperature, which is about 1/10 that of iron or nickel. However, the thermal expansion coefficients of the base body 31, the lid body 34, the support members 35, etc. may be the same or different.

  Since the low thermal expansion material is a material that is not easily deformed by heat, the low thermal expansion material is not easily affected by friction caused by movement of the stage 11 or heat generation due to motor activation. Therefore, by forming the base body 31, the lid body 34, each support member 35, etc. using a low thermal expansion material, it is possible to suppress deformation of the base body 31, the lid body 34, each support member 35, etc. with respect to temperature changes. It becomes possible. Thereby, since the inclination of the optical barrel 2b due to deformation of the base body 31, the lid 34, each support member 35, etc. is suppressed, the stability of the drawing accuracy can be improved.

  The vacuum vessel 2a is required to have a vacuum holding function for preventing leakage between the atmosphere side and the vacuum side, but the low-purity low thermal expansion material may contain defects such as bubbles inside. . In this case, when the low thermal expansion material is processed, defects appear on the surface and a good bonding surface (seal surface) cannot be formed, and a desired vacuum holding function may not be obtained. For this reason, it is desirable to use a high purity low thermal expansion material for the vacuum vessel 2a.

  Here, the vacuum vessel 2a can be composed of only a high-purity low thermal expansion material, for example, a high-purity invar. However, the high-purity invar increases the number of manufacturing steps compared to the low-purity invar. Therefore, it is not easy to obtain and the price is high. For this reason, it is desirable to use high-purity invar only for the joint portion (seal portion) of the vacuum vessel 2a and use low-purity invar for portions other than the joint portion. Thereby, the manufacturing time of the apparatus can be shortened and the manufacturing cost can be suppressed. For example, it is desirable that the portion where the seal is formed by the O-ring 42, that is, the joint portion 36a of the elastic member 36 is made of high-purity invar.

  Invar purity is expressed in terms of phosphorus (P) and sulfur (S) concentrations. Specifically, the higher the concentration of phosphorus and sulfur, the lower the purity of Invar. In this embodiment, phosphorus and sulfur both having a predetermined concentration or less are defined as “high purity invar”. For example, “high-purity invar” is one in which phosphorus and sulfur are each 0.001% by mass or less. In this case, one in which either phosphorus or sulfur exceeds 0.001% by mass becomes “low-purity invar”. It is desirable that the concentration of phosphorus and sulfur in the seal part be 1/10 or less of the concentration of phosphorus and sulfur in the non-seal part.

  In the above-described embodiment, one end of the elastic member 36 is fixed to the outer peripheral end of the lid 34, and the other end is fixed to the upper surface wall 32 b of the first housing 32 by the fixing member 41. However, the present invention is not limited to this (see FIG. 4), and both ends of the elastic member 36 may be fixed by the same method, that is, welding or a fixing member.

  Further, in the above-described embodiment, one end portion of the expansion / contraction member 36 is fixed to the end portion on the outer peripheral side of the lid body 34 (see FIG. 4). It may be fixed to the side, for example, the boundary (or the optical barrel 2b) between the lid 34 and the optical barrel 2b. In this case, deformation of the lid 34 due to atmospheric pressure can be reliably prevented. However, the thickness of the lid 34 supported by the support member 35 is the sum of the thickness of the lid 34 and the thickness of the support member 35, and the width of the annular portion of the lid 34 is small. The optical barrel 2b can be prevented from being tilted without being deformed by several tens of μm due to the atmospheric pressure. On the other hand, when a deformation smaller than several tens of μm, for example, about several μm, becomes a problem, one end portion of the elastic member 36 is connected to the inner peripheral side of the lid 34, for example, the lid 34 and the optical barrel 2b. It is effective to fix to the boundary. As a result, only the vacuum pressure is applied to both the front and back surfaces of the lid 34 and the lid 34 is not affected by the external atmospheric pressure, so that it is not deformed to several μm.

  In the above-described embodiment, the mirror 11a and the laser interferometer 13 are used as means for grasping the position of the stage 11. However, the present invention is not limited to this. A linear sensor facing the linear scale can be mounted on the stage 11. In this case, the mark row is detected by the linear sensor, and the position of the stage 11 is grasped. Just as two sets of mirror 11a and laser interferometer 13 are provided for X direction and Y direction, two sets of linear scale and linear sensor are provided for X direction and Y direction. The position of the stage 11 in the X direction and the Y direction is grasped.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of 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 1 Charged particle beam drawing apparatus 2 Drawing part 2a Vacuum container 2a1 Opening part 2b Optical barrel 3 Control part 3a Drawing data storage part 3b Shot data generation part 3c Drawing control part 11 Stage 11a Mirror 12 Moving mechanism 13 Laser interferometer 14 Drive part DESCRIPTION OF SYMBOLS 21 Outgoing part 22 Illumination lens 23 1st shaping | molding aperture 24 Projection lens 25 Molding deflector 26 2nd shaping | molding aperture 27 Objective lens 28 Sub deflector 29 Main deflector 31 Base plate 31a Through-hole 32 1st housing | casing 32a Side wall 32b Upper surface wall 33 Second housing 33a Side wall 33b Bottom wall 34 Lid 34a Through hole 35 Support member 36 Elastic member 36a Joint portion 36a1 Recess 37 Support base 41 Fixing member 42 O-ring B Electron beam M1 First surface M2 Second Surface K1 First internal space K2 Second internal space W Sample

Claims (5)

An optical barrel containing a charged particle optical system;
A vacuum vessel having an opening formed on the upper surface;
The optical barrel is fixed, and a lid for closing the opening;
A base body which is provided in the vacuum vessel and divides the internal space of the vacuum vessel into a first internal space on the upper surface side of the vacuum vessel and a second internal space on the bottom surface side of the vacuum vessel, and has a through hole formed When,
A plurality of support members fixed to the base body and provided in the first internal space of the vacuum vessel, and supporting the lid;
An extendable / contractible member that connects the vacuum vessel and the lid and seals the vacuum vessel;
A charged particle beam drawing apparatus comprising:   The charged particle beam drawing apparatus according to claim 1, further comprising a laser interferometer fixed to the support member.   The charged particle beam drawing apparatus according to claim 1, wherein the elastic member is fixed to the lid body by welding, and is fixed to the vacuum vessel by a fixing member. The elastic member has a joint portion joined to the vacuum vessel by the fixing member,
The charged particle beam drawing apparatus according to claim 3, wherein the joint portion is formed of a material having a lower concentration of phosphorus and sulfur than other portions of the elastic member. 5. The base body and the plurality of support members are formed of a material having a linear expansion coefficient of 2 × 10 ⁻⁶ / K or less at room temperature. The charged particle beam drawing apparatus described in 1.

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