JP2005317810A - Electron beam exposure device, method for measuring distortion of and correcting deflected position of electron beam, and semiconductor wafer and exposure mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron beam exposure device for irradiating and scanning over a mask having a mask pattern according to an exposure pattern with an electron beam generated by an electron beam source using a deflection means, for performing the exposure of the exposure pattern to the electron beam passing through the mask, and for performing high precision correction of deflection distortion in this deflection means; and capable of carrying out the work required in this correction in a short time. <P>SOLUTION: The electron beam exposure device 1 comprises: support means 43, 44 for positioning a position detection mark 46 to produce secondary electrons by the irradiation with the electron beam 15 at the known position in the deflection region of the deflection means 21 and 22; a deflection command amount acquiring unit 72 for acquiring the deflection command amount when the secondary electrons produced by this position detection mark 46 are detected; and a correction unit 74 which, in order to deflect the electron beam 15 to the known position of the position detection mark, corrects a predetermined deflection command amount corresponding to that position to obtain the acquired deflection command amount. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is an electron beam that is used in a manufacturing process of a semiconductor integrated circuit and the like, deflects an electron beam generated by an electron beam source, and scans a mask having a mask pattern corresponding to the exposure pattern to expose the exposure pattern. The present invention relates to an exposure apparatus, a method for measuring distortion of the deflection position of the electron beam, a method for correcting the deflection position of the electron beam, and a semiconductor wafer used in these methods.

  In recent years, with the need for higher integration of semiconductor integrated circuits, further miniaturization of circuit patterns has been demanded. At present, the limits of miniaturization are mainly limited to exposure apparatuses, and new exposure apparatuses such as an electron beam direct writing apparatus and an X-ray exposure apparatus have been developed.

  Recently, an electron beam proximity exposure apparatus that can be used for ultrafine processing at a mass production level has been disclosed as a new type of exposure apparatus (for example, Patent Document 1 and Patent Document 2 corresponding to Japanese Patent Application). .

  FIG. 1 is a diagram showing a basic configuration of an electron beam proximity exposure apparatus disclosed in Patent Document 1. As shown in FIG. The electron beam proximity exposure apparatus will be briefly described with reference to this figure. As shown in the figure, an electron gun 12 having an electron beam source 14 for generating an electron beam 15, a shaping aperture 18, and an irradiation lens 16 for converting the electron beam 15 into a parallel beam is disposed in an electron optical column (column) 10. Scanning means 13 for scanning the electron beam 15 parallel to the optical axis 19 and a mask having an opening corresponding to the pattern to be exposed, which includes a pair of main deflectors 21 and 22 and a pair of sub-deflectors 51 and 52 30, and an electrostatic chuck 43 and an XY stage 44. A sample (semiconductor wafer) 40 has a resist layer 42 formed on the surface thereof and is held on an electrostatic chuck 43.

  The sample 40 is arranged so that the surface is close to the mask 30. When the electron beam 15 is irradiated perpendicularly to the mask 30 in this state, the electron beam 15 that has passed through the opening of the mask 30 is irradiated to the resist layer 42 on the surface of the sample 40.

Each deflection command amount for commanding the deflection amount by which the main deflectors 21 and 22 of the scanning means 13 deflect the electron beam 15 to each deflection position in a predetermined deflection region corresponds to each deflection position. It is predetermined.
The main deflectors 21 and 22 receive the deflection command amount from an external control device via a signal line (not shown), generate an electric field and / or a magnetic field corresponding to the received deflection command amount, and generate the electron beam 15. Can be deflected. The electron beam 15 is deflected to a deflection position determined in accordance with the deflection command amount by the electric field and / or magnetic field generated by the main deflectors 21 and 22.

  Thereby, the main deflectors 21 and 22 control the deflection of the electron beam so that the electron beam 15 scans the entire surface of the membrane portion where the exposure pattern on the mask 30 is provided, as shown in FIG. As a result, the mask pattern of the mask 30 is transferred to the resist layer 42 on the sample 40 at the same magnification.

  The XY stage 44 moves the sample 40 adsorbed on the electrostatic chuck 43 in two horizontal orthogonal horizontal directions, and moves the sample 40 by a predetermined amount each time the mask pattern is transferred at an equal magnification. A plurality of mask patterns can be transferred to a single sample 40.

The sub deflectors 51 and 52 in the scanning unit 13 control (tilt control) the incident angle of the electron beam 15 on the mask pattern so as to correct the mask distortion. As shown in FIG. 3, when the incident angle of the electron beam 15 to the exposure mask 30 is α and the gap between the exposure mask 30 and the wafer 40 is G, the shift amount δ of the transfer position of the mask pattern due to the incident angle α. Is
δ = G ・ tanα
It is represented by In FIG. 3, the mask pattern is transferred to a position shifted from the normal position by a shift amount δ.

  Therefore, when the exposure mask 30 has a mask distortion as shown in FIG. 4A, for example, the tilt of the electron beam is controlled according to the mask distortion at the electron beam scanning position. As shown in FIG. 4B, it is possible to transfer the mask pattern without mask distortion.

US Pat. No. 5,831,272 (Overall) Japanese Patent No. 2951947 (Overall)

The pattern line width formed on the resist layer 42 exposed by the above-described electron beam exposure apparatus and subsequently developed is determined by the exposure amount of the electron beam 15, that is, the current amount and exposure time of the electron beam 15. Varies depending on the product of
Therefore, in order to prevent unevenness of the formed pattern line width and prevent deterioration of resolution, while maintaining the current value of the electron beam 15, the scanning speed of the electron beam 15 on the mask is set to a predetermined accuracy. Need to be controlled and maintained at. For this reason, the scanning means 13 (especially the main deflectors 21 and 22) must control the deflection position of the electron beam 15 on the mask with high accuracy.

  However, in practice, the main deflector 21 is affected by mechanical attachment errors when attaching the scanning means 13, particularly the main deflectors 21, 22, to the column 10, and differences in the characteristics of the electrodes constituting each deflector. , 22 generates distortion (deflection distortion) in the electric field and / or magnetic field. Due to this deflection distortion, the actual deflection position of the electron beam deflected by the main deflectors 21 and 22 to which a predetermined deflection command amount corresponding to the desired deflection position is input, and the desired deflection There was a phenomenon where the position did not match. Such a deviation between the desired deflection position and the actual deflection position causes fluctuations in the scanning speed of the electron beam 15 on the mask, resulting in uneven exposure amount of the electron beam 15 on the sample 40 and deterioration of resolution. It was causing.

  In order to correct such deflection distortion of the main deflectors 21 and 22, conventionally, the electron beam 15 is deflected by each deflection command amount determined corresponding to each position in the deflection region of the main deflectors 21 and 22. Then, the deflected electron beam 15 is detected by moving an electron detector placed on a table mechanism or the like capable of controlling the position with high accuracy to the irradiation position, thereby detecting the actual deflection position of the electron beam 15. Conventionally, deflection distortion measurement is performed to measure the deflection distortion amount by comparing each deflection position determined corresponding to each deflection command amount and each actually detected deflection position. .

  However, according to such a method, since the electron detector is moved for each measurement position, if the number of measurement points is increased in order to improve the correction accuracy, the measurement work increases and the operation time of the exposure apparatus is reduced.

  In view of the above problems, the present invention is directed to an electron beam that has passed through a mask by irradiating an electron beam generated from an electron beam source so as to scan on a mask having a mask pattern corresponding to an exposure pattern by a deflecting unit. Provided is an electron beam exposure apparatus that exposes an exposure pattern with a beam, which can correct the deflection distortion of the deflecting means with high accuracy and can perform the work required for the correction in a short time. With the goal.

  Further, the present invention irradiates an electron beam generated from an electron beam source so as to scan on a mask having a mask pattern corresponding to the exposure pattern by the deflecting means, and the exposure pattern is formed by the electron beam passing through the mask. An object of the present invention is to provide an electron beam deflection position distortion measuring method capable of measuring the deflection distortion of the deflecting means with high accuracy and performing the work required for the measurement in a short time in the electron beam exposure. And

  Furthermore, the present invention is such that an electron beam generated from an electron beam source is irradiated by a deflecting means so as to scan on a mask having a mask pattern corresponding to the exposure pattern, and the exposure pattern is emitted by the electron beam passing through the mask. It is an object of the present invention to provide a method for correcting the deflection position of an electron beam capable of correcting the deflection distortion of the deflecting means with high accuracy and performing the work required for the correction in a short time. .

  In order to achieve the above object, according to the present invention, a position detection mark that generates secondary electrons when irradiated with an electron beam is positioned at a known position in the deflection area of the deflecting means, and 2 generated from the position detection mark. A deflection command amount at the time of detecting the next electron is acquired, and a deflection command amount predetermined corresponding to the position for deflecting the electron beam to a known position detection mark position, and the obtained deflection command amount In comparison, the deflection distortion is obtained.

  That is, the electron beam exposure apparatus according to the first embodiment of the present invention is predetermined in advance corresponding to each position on the mask, an electron beam source that generates an electron beam, a mask having a mask pattern corresponding to the exposure pattern, and the like. Deflecting means for deflecting the electron beam to each position in accordance with the input of each deflection command amount, and exposing the exposure pattern on the sample surface with the electron beam that has passed through the mask by irradiating the electron beam onto the mask. An electron beam exposure apparatus, further comprising a position detection mark support means for positioning and supporting a position detection mark that generates secondary electrons when irradiated with an electron beam at a known position in a deflection area of the electron beam by the deflection means An electron detector that detects secondary electrons generated when the position detection mark is irradiated with an electron beam, and a deflection finger that is input to the deflection means when the secondary electrons are detected. Comprising a deflection command amount acquiring means for acquiring the amount, the deflection command value predetermined corresponding to the position of the position detection mark, and correcting means for correcting the acquired deflection command amount.

  Further, in the distortion measuring method of the deflection position of the electron beam according to the second embodiment of the present invention, the electron beam generated by the electron beam source is placed at each position on the mask having a mask pattern corresponding to the exposure pattern. Correspondingly, an electron beam is deflected and irradiated by deflecting means for deflecting the electron beam to each position in accordance with the input of each predetermined deflection command amount, and the exposure pattern is exposed on the sample surface with the electron beam passing through the mask. A method for measuring the distortion of the deflection position of an electron beam by a deflecting unit in electron beam exposure, wherein a position detection mark that generates secondary electrons when irradiated with an electron beam is known within a deflection region of the electron beam by the deflecting unit. The position detection mark support step for positioning and supporting at the position and the deflection command amount are input to the deflecting means while being changed, and the electron beam is placed on the position detection mark. An electron beam scanning step to be inspected, an electron detection step for detecting secondary electrons generated when the position detection mark is irradiated with the electron beam, and a deflection command amount input to the deflecting means when the secondary electrons are detected. And a comparison step for obtaining a difference between the deflection command amount determined corresponding to the position of the position detection mark and the deflection command amount acquired in the deflection command amount acquisition step.

  Still further, the electron beam deflection position correcting method according to the third aspect of the present invention corresponds to each position of the electron beam generated by the electron beam source on each position on the mask having a mask pattern corresponding to the exposure pattern. Then, the electron beam is deflected and irradiated by deflecting means for deflecting the electron beam to each position in accordance with each predetermined deflection command amount input, and the exposure pattern is exposed on the sample surface with the electron beam that has passed through the mask. A method for correcting the deflection position of an electron beam by a deflecting unit in electron beam exposure, wherein a position detection mark that generates secondary electrons when irradiated with an electron beam is a known position within a deflection region of the electron beam by the deflecting unit. The position detection mark support step for positioning and supporting the position detection mark, the deflection command amount being changed and input to the deflection means, and the electron beam traveling on the position detection mark. An electron beam scanning step, an electron detection step for detecting secondary electrons generated when the position detection mark is irradiated with the electron beam, and a deflection command amount input to the deflection means when the secondary electrons are detected. A deflection command amount acquisition step; and a correction step of correcting a deflection command amount determined in advance corresponding to the position of the position detection mark to the acquired deflection command amount.

A plurality of position detection marks may be provided. At this time, an electron beam is scanned on each position detection mark by the deflection means, and secondary electrons generated from the position detection marks by the deflection command amount acquisition means. Each deflection command amount at the time of detection may be acquired.
Then, each deflection command amount predetermined corresponding to the position of each position detection mark may be corrected to each obtained deflection command amount by the correction unit, or by the comparison unit, The deflection distortion amount may be measured by obtaining a difference between each deflection command amount predetermined in correspondence with the position of each position detection mark and each obtained deflection command amount.

  It is preferable that at least a part of the edge of the position detection mark has a linear shape in a predetermined direction. At this time, the deflecting unit scans the edge of the position detection mark with the electron beam in a predetermined vertical direction, and the deflection command amount acquiring unit detects the secondary electrons accompanying the change in the scanning position of the electron beam. It is preferable to acquire a deflection command amount corresponding to the position of the edge in the vertical direction of the predetermined direction based on the change in value.

  The position detection mark may be realized as a heavy metal or a step formed on the surface of the semiconductor wafer or the surface of the mask. The position detection mark support means is used as the semiconductor wafer support means, and the position is detected on the surface by the semiconductor wafer support means. The semiconductor wafer on which the detection mark is formed may be supported, and the position detection mark support unit may be used as a mask support unit, and the mask on which the position detection mark is formed may be supported by the mask support unit.

  The semiconductor wafer according to the fourth embodiment of the present invention has a position detection mark which is a heavy metal portion or a step portion formed on the surface thereof, and the method for measuring the distortion of the deflection position of the electron beam according to the second embodiment of the present invention and the present invention. This is used for the electron beam deflection position correction method according to the third embodiment.

  According to the present invention, in order to correct or measure the deflection distortion of the deflecting means of the electron beam exposure apparatus, when obtaining the deviation between the desired deflection position by the deflecting means and the actual deflection position, the position is known. Since only the electron beam needs to be deflected to the detection mark, the deflection distortion can be corrected or measured in a very short time.

In this way, the time required for correcting or measuring the deflection distortion can be made very short, so it becomes easy to increase the number of measurement points of the deflection position, and the deflection distortion can be corrected or measured with higher accuracy than before. Can be performed. As a result, the uniformity of the electron beam irradiation amount (exposure amount) of the electron beam exposure apparatus can be improved, and the resolution of the pattern exposed to the sample can be improved.
In addition, when an exposure pattern is overlaid on a sample on which a lower layer pattern has already been formed in the previous process, the accuracy of the position at which the pattern is exposed on the sample is improved by improving the accuracy of deflection distortion correction. And the overlay accuracy is improved.

The deflection distortion occurs in the X direction and the Y direction on the mask surface. Accordingly, at least a part of the edge of the position detection mark is linearly formed in a predetermined direction (for example, the Y direction), and the deflecting unit is perpendicular to the edge of the position detection mark in the predetermined direction (the X direction in this example). By scanning the electron beam, even if the electron beam deflection position fluctuates in a predetermined direction (Y direction in this example) due to deflection distortion, the edge position and the electron beam deflection position are perpendicular to each other in the predetermined direction. It is possible to keep the relative positional relationship in the direction (X direction in this example) constant.
Thus, even if the electron beam deflection position fluctuates in a predetermined direction (Y direction in this example) due to deflection distortion, the deflection command corresponding to the vertical direction position (X direction position in this example) of this edge portion. It becomes possible to acquire the amount accurately.

  In addition, by using a heavy metal part or stepped part formed on the surface of the semiconductor wafer similar to the sample of the exposure apparatus as the position detection mark, the deflection distortion is corrected or measured in the same positional relationship as the sample to be exposed. Thus, more accurate correction and measurement can be performed.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 5 is a schematic block diagram of an electron beam exposure apparatus according to an embodiment of the present invention. In the following description, an electron beam proximity exposure apparatus 1 of the proximity exposure method is exemplified as the electron beam exposure apparatus 1, but the electron beam exposure apparatus of the present invention is not only an electron beam proximity exposure apparatus but also a mask corresponding to an exposure pattern. Any electron beam exposure apparatus that irradiates a mask having a pattern with an electron beam and exposes an exposure pattern onto the sample with an electron beam passing through the mask can be used for other types of electron beam exposure apparatuses.

  In the following drawings, when a plurality of elements having the same configuration are provided, the same reference numerals may be indicated by adding alphabets, and the description of each element may be expressed by only the reference numerals. Further, the basic configuration of the electron beam proximity exposure apparatus has a configuration similar to the configuration shown in FIG. 1 and the configuration disclosed in Document 1 above. Therefore, the same functional parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 5, an electron beam proximity exposure apparatus 1 includes an electron gun 12 having a column 10 and an electron beam source 14 that generates an electron beam 15 and an irradiation lens 16 that converts the electron beam 15 into a parallel beam. A scanning unit 13 that includes deflectors 21 and 22 and sub-deflectors 51 and 52 that deflects the electron beam 15 so as to scan the electron beam 15 parallel to the optical axis 19, and a mask having an opening corresponding to the pattern to be exposed. 30 and a mask stage 36 having a mask chuck for supporting the mask 30 and moving the mask 30 at least in the horizontal two-axis directions (XY directions). Here, the mask stage 36 constitutes a mask support means for supporting the mask 30.
In the following description, the deflection distortion of the electron beam according to the present invention is measured and corrected in a state where the mask 30 is not attached. Therefore, in FIG. 5, the mask 30 is displayed with a dotted line.

On the other hand, the electron beam proximity exposure apparatus 1 includes an electrostatic chuck 43 and an XY stage 44 in the chamber 8. The electrostatic chuck 43 is a semiconductor wafer support unit that supports the semiconductor wafer as the sample 50.
The mask 30 is disposed so as to be close to the surface of the sample 40 adsorbed by the electrostatic chuck 43 (so that the gap between the mask 30 and the sample 40 is, for example, 50 μm).
In measurement and correction of deflection distortion of an electron beam according to the present invention described below, a measurement wafer 45 having a position detection mark described in detail below formed on the surface is placed on the electrostatic chuck 43.

The electron beam proximity exposure apparatus 1 includes a computer 91 that is a control device such as a computer that controls the overall operation of the electron beam proximity exposure apparatus 1.
The electron beam proximity exposure apparatus 1 includes a memory 93 for storing a program executed by the computer 91 and various data. The memory 93 is connected to the bus 92 of the computer 91, whereby data can be exchanged with the computer 91 and other components that use the bus 92.
The memory 93 also stores position data of position detection marks formed on the measurement wafer 45.

In the electron beam proximity exposure apparatus 1, the main deflectors 21 and 22 of the scanning unit 13 provide the main deflectors 21 and 22 with a deflection command amount for deflecting the electron beam 15 to each deflection position in a predetermined deflection region. A deflection command amount supply unit 94 for supplying is provided. The deflection command amount supply unit 94 is connected to the bus 92 of the computer 91, so that data can be exchanged with the computer 91 and other components that use the bus 92. Each deflection position in the deflection region of the main deflectors 21 and 22 and each deflection command amount necessary for deflecting the electron beam to this position are determined in advance in the form of a table or a map, respectively. The information is stored in a memory 93 (not shown) built in the memory 93 or the deflection command amount supply unit 94.
A deflection command amount which is a digital signal supplied from the deflection command amount supply unit 94 is converted into an analog signal by a digital-analog converter (hereinafter referred to as DAC) 23, and then amplified by an amplifier 24 to be amplified by the main deflector 21. , 22.

  Further, the electron beam proximity exposure apparatus 1 detects secondary (reflected) electrons 17 generated by irradiating the position detection mark formed on the measurement wafer 45 held by the electrostatic chuck 43 with the electron beam 15. Secondary electron detector 71 that performs this operation, and a deflection command amount acquisition unit 72 that acquires the deflection command amount input to the DAC 23 from the deflection command amount supply unit 94 when the secondary electron detector 71 detects secondary electrons. With. The deflection command amount acquisition unit 72 is connected to the bus 92 of the computer 91, so that data can be exchanged with the computer 91 and other components using the bus 92. The deflection command amount acquisition unit 72 stores the acquired command amount in the memory 93 via this bus.

Further, the electron beam proximity exposure apparatus 1 acquires the position information of the position detection mark from the memory 93, and acquires the deflection command amount determined corresponding to this position from the memory 93 or the deflection command amount supply unit 94. And a comparison unit 73 for obtaining a difference between this and the deflection command amount acquired by the deflection command amount acquisition unit 72.
Further, the electron beam proximity exposure apparatus 1 determines a deflection command amount that is predetermined in correspondence with the same deflection position as the position detection mark and stored in the memory 93 or the deflection command amount supply unit 94 as a deflection command amount acquisition unit. A correction unit 74 that corrects the deflection command amount acquired by 72 is provided.
The comparison unit 73 and the correction unit 74 are also connected to the bus 92 of the computer 91, so that data can be exchanged with the computer 91 and other components that use the bus 92.

  Furthermore, the electron beam proximity exposure apparatus 1 includes an imaging unit 83 such as a CCD camera for imaging an alignment mark formed on the measurement wafer 45 and having a known relative positional relationship with the position detection mark, and an imaging unit 83. An alignment unit 84 that positions the position detection mark at a known position in a predetermined deflection area of the main deflectors 21 and 22 with high accuracy based on the captured image and the positional information of the XY stage 44 at the time of imaging is provided.

FIG. 6 is a flowchart of the method for measuring the distortion of the deflection position of the electron beam according to the present invention. Hereinafter, the distortion measurement of the deflection position in the X direction will be described.
In step S <b> 101, the measurement wafer 45 provided with the plurality of position detection marks 46 </ b> A to 46 </ b> P shown in FIG. 7A is placed on the electrostatic chuck 43 on the XY stage 44 and supported by the electrostatic chuck 43. For the sake of explanation, the X coordinate axis and the Y coordinate axis on the measurement wafer 45 are determined as shown in FIG.
The position detection mark 46 may be formed by providing a step on the surface (exposure surface) of the measurement wafer 45 which is a semiconductor wafer. In order to increase the S / N ratio of secondary electrons generated from the position detection mark 46. In addition, (heavy) metal portions such as tantalum (Ta), tungsten (W), copper (Cu), aluminum (Al), tantalum silicide (TaSiXX) and titanium silicide (TiSiXX) may be formed and provided. . At this time or in advance, each position data of each position detection mark 46 is given to the electron beam proximity exposure apparatus 1 and stored in the memory 93.

After placing the measurement wafer 45 on the electrostatic chuck 43, the XY stage 44 moves the measurement wafer 45 to the alignment mark imaging position. At the alignment mark imaging position, the imaging unit 83 images an alignment mark (not shown) formed on the measurement wafer 45. The relative positional relationship between the alignment mark and each position detection mark 46 is given in advance to the electron beam proximity exposure apparatus 1 and stored in the memory 93.
Thereby, the alignment unit 84 is based on the position of the alignment mark in the captured image by the imaging unit 83, the positional information of the XY stage 44 at the time of imaging, and the relative positional relationship between the alignment mark and the position detection mark 46. Each relative positional relationship between a predetermined deflection area of the main deflectors 21 and 22 and each position detection mark 46 is calculated.

  The alignment unit 84 controls the positioning of the XY stage 44 so that each position detection mark 46 is positioned at each known deflection position in the deflection region 25 of the main deflectors 21 and 22 (FIG. 7A).

  In step S102, the deflection command amount supply unit 94 reads out a deflection command amount that is predetermined and stored in correspondence with the X-direction scanning start deflection position 27X from the memory 93 or its own built-in memory. The signal is input to the main deflectors 21 and 22 through the amplifier 24. Thereby, in step S103, the electron beam 15 is irradiated in the vicinity of the X-direction scanning start deflection position 27X. At this time, the actual irradiation position of the electron beam 15 on the wafer 45 is slightly deviated from the desired X-direction scanning start deflection position 27X due to the deflection distortion of the main deflectors 21 and 22 described above. Hereinafter, the distortion measurement of the deflection position in the X direction will be described.

  In step S <b> 104, the deflection command amount acquisition unit 72 determines whether or not the secondary electrons 17 generated by irradiating the position detection mark 46 with the electron beam 15 are detected by the electron detector 71. If the secondary electrons 17 have not been detected, the process proceeds to step S105, where the deflection command amount supply unit 94 increases the deflection command amount in the X direction and inputs it to the main deflectors 21 and 22, and the electron beam 15 is traced. Move along 26X.

  After repeating these steps S103 to S105, when the position detection mark 46 is irradiated with the electron beam 15, the secondary electrons 17 generated from the position detection mark 46 are detected by the electron detector 71, and the process proceeds to step S106. .

In step S <b> 106, the deflection command amount acquisition unit 72 inputs the deflection command amount supply unit 94 to the main deflectors 21 and 22 when the electron detector 71 detects the secondary electrons generated from the position detection marks 46. Get the deflection command amount.
In step S <b> 107, the deflection command amount acquisition unit 72 stores the acquired deflection command amount in the memory 93.
Steps S102 to S107 are performed until scanning is performed on the plurality of position detection marks 46A to 46P positioned in the deflection regions of the main deflectors 21 and 22 while moving the deflection position of the electron beam 15 along the locus 26X. Repeated (S108).

In step S109, the comparison unit 73 reads the position of each position detection mark 46 stored in the memory 93, and supplies a predetermined deflection command amount corresponding to each read position to the memory 93 or the deflection command amount supply. Read from the internal memory of the unit 94.
On the other hand, the comparison unit 73 reads each deflection command amount acquired by the deflection command amount acquisition unit 72 and stored in the memory 93 in step S <b> 106 from the memory 93. Then, a difference between each deflection command amount determined in advance corresponding to the position of each position detection mark 46 and each deflection command amount acquired by the deflection command amount acquisition unit 72 corresponding thereto is obtained. The difference between these deflection command amounts is that each deflection command amount determined in advance corresponding to deflecting the electron beam 15 to the position of each position detection mark 46 is actually different from each position detection mark 46. In order to express the deviation in the X direction of each deflection command amount when deflected to the position, this is acquired as the deflection distortion amount in the X direction.

An example of the method of acquiring the deflection command amount in step S106 will be specifically described with reference to FIGS. 8 (A) and 8 (B). FIG. 8A shows the positional relationship between the electron beam irradiation position and the position detection marks 46A, 46B, 46C and 46D when the electron beam 15 is scanned in the X direction.
As shown in FIG. 8A, each of the position detection marks 46A, 46B, 46C and 46D has a substantially rectangular shape, and the coordinates of one corner thereof are (XA1, YA1), (XB1, YB1), respectively. , (XC1, YC1) and (XD1, YD1), and the coordinates of the diagonal corners are (XA2, YA2), (XB2, YB2), (XC2, YC2) and (XD2, YD2), respectively. It will be determined.

When the electron beam 15 having a diameter smaller than the side of each position detection mark 46 is also scanned on each position detection mark 46A, 46B, 46C and 46D along the locus 26X, the waveform of the detection signal of the electron detector 71 The figure is as shown in FIG.
The secondary electron detection value increases when the electron beam 15 is irradiated to the edge portion (edge portion) of each position detection mark 46. Therefore, the signal waveform of the secondary electron detection value when the electron beam 15 is scanned on the position detection mark 46 in the X direction is such that the irradiation position of the electron beam 15 has a linear shape in the Y direction of each position detection mark 46. The peak value is taken when the side is on the sides A1, A2, B1, B2, C1, C2, D1, and D2.

Therefore, each position detection mark 46A, 46B, 46C and 46D is an XA1 which is an X coordinate of each of the sides A1, A2, B1, B2, C1, C2, D1, and D2, which are sides having a linear shape in the Y direction. , XA2, XB1, XB2, XC1, XC2, XD1, and XD2 are used as position data of each position detection mark 46A, 46B, 46C, and 46D in the X direction.
Then, when the electron beam 15 is irradiated onto the sides A1, A2, B1, B2, C1, C2, D1, and D2, the deflection command amount supply unit 94 detects the peak value of the detection signal of the electron detector 71. The respective deflection command amounts XDA1, XDA2, XDB1, XDB2, XDC1, XDC2, XDD1, and XDD2 input to the main deflectors 21 and 22 are respectively detected in the X direction positions of the position detection marks 46A, 46B, 46C, and 46D. Acquired as each deflection command amount corresponding to the data.

  FIG. 9A shows the positional relationship between the position detection mark 46 and the position detection mark 46 when the position detection mark 46 is scanned in the X direction with the electron beam 15 having a diameter larger than the length of its side. FIG. As shown in FIG. 9A, each position detection mark 46 has a substantially rectangular shape, the coordinates of one corner of the position detection mark 46 are defined as (X1, Y1), and the coordinates of the corner of the diagonal are (X2, Y2). ). The waveform diagram of the detection signal of the electron detector 71 at this time is shown in FIG. 9B, and the waveform diagram of the first derivative value of the detection signal of the electron detector 71 is shown in FIG. 9C.

  As shown in FIG. 9C, the primary differential waveform of the secondary electron detection value when the electron beam 15 is scanned on the position detection mark 46 in the X direction indicates that the irradiation position of the electron beam 15 is the position detection. When the mark 46 is on the sides A1 and A2, which are sides having a linear shape in the Y direction, the maximum value and the minimum value are taken.

  Therefore, when the electron beam 15 having a diameter larger than the length of the side is used for the position detection mark 46, the sides A1 and A2, which are sides having a linear shape in the Y direction of the position detection mark 46, are used. The respective X coordinates X1 and X2 are used as position data of the position detection mark 46 in the X direction. The deflection command amount supply unit 94 inputs the deflection command amounts XD1 and XD1 input to the main deflectors 21 and 22 when the first-order differential waveform of the detection signal of the electron detector 71 detects the maximum value and the minimum value. XD2 is acquired as each deflection command amount corresponding to the position data of the position detection mark 46 in the X direction.

  Although the deflection position distortion measurement in the X direction has been described above, the deflection position distortion measurement in the Y direction can be performed by changing the scanning direction of the electron beam 15 by 90 °. FIG. 7B is a diagram showing each of the position detection marks 46A to 46P and a locus 26Y when scanning the electron beam 15 in the Y direction when measuring the distortion of the deflection position in the Y direction. 8 (C) is a waveform diagram of a detection signal of the electron detector 71 when the position detection marks 46A, 46E, 46I, and 46M are scanned along the locus 26Y. FIG. It is a figure which shows the positional relationship of the electron beam irradiation position and position detection mark 46A, 46E, 46I, and 46M when scanning the beam 15 to a Y direction.

  The distortion measurement of the deflection position with respect to the Y direction is performed in the same manner as the measurement of the distortion of the deflection position with respect to the X direction described above with reference to FIGS. 6, 7A, 8A, and 8B. The description is omitted to avoid duplication.

  Each position detection mark 46 preferably has a linear edge in a direction perpendicular to a direction in which the deflection position distortion amount of the electron beam 15 is measured or a deflection position correction described later is performed. The reason for this will be described with reference to FIGS. 10 (A) and 10 (B).

  FIG. 10A is a top view of the position detection mark 46 having an edge of a straight line portion in a direction perpendicular to the direction in which the deflection position distortion amount of the electron beam 15 is measured or the deflection position correction is performed. A case will be described in which the X direction and the Y direction are determined as illustrated, and the deflection position distortion amount of the electron beam 15 is measured in the X direction or the deflection position correction described later is performed. Hereinafter, the direction in which the deflection distortion amount of the electron beam 15 is measured or the deflection position correction is performed is referred to as the X direction, and the direction perpendicular thereto is referred to as the Y direction.

As the X direction position data of the position detection mark 46, the X coordinate XE of the side A1, which is a side having a linear shape in the Y direction of the position detection mark 46, is used. Furthermore, the method described above with reference to FIG. 8 is used as a method of acquiring the deflection command amount by the deflection command amount acquisition unit 72 (see step S106).
That is, when the electron beam 15 is scanned along the locus 26X in the X direction (direction perpendicular to the direction of the side A1) by the main deflectors 21 and 22, the side A1 is irradiated with the electron beam 15. The deflection command amount input to the main deflectors 21 and 22 of the deflection command amount supply unit 94 at the time when the peak value of the detection signal of the electron detector 71 is detected is the deflection command corresponding to the position data of the position detection mark 46 in the X direction. It will be acquired as a quantity.

  Here, the deflection distortion of the main deflectors 21 and 22 occurs in both the X direction and the Y direction. Therefore, in a state where there is a deflection distortion in the Y direction, the electron beam 15 is not always scanned accurately along the locus 26X. May also be biased in the Y direction.

  Accordingly, the position detection mark 46 is provided with a linear edge A1 in the Y direction, which is a direction perpendicular to the X direction, and the deflection command amount acquisition unit 72 performs deflection when the edge A1 is irradiated with an electron beam. If the command amount is acquired, even if the locus 26 of the electron beam 15 is deviated in the Y direction, the electron beam 15 in the X direction when the electron beam 15 irradiates the edge A1. The X coordinate of the deflection position can be made constant. Thereby, it is possible to prevent the influence of the deflection distortion in the Y direction of the electron beam 15 on the input deflection command amount acquired by the deflection command amount acquisition unit 72 in the X direction.

  On the other hand, FIG. 10B is a top view of the position detection mark 46 that does not have the edge of the straight line portion in the direction perpendicular to the direction in which the deflection distortion amount of the electron beam 15 is measured or the deflection position is corrected. In the case of the position detection mark 46 in FIG. 10B, if the locus 26X ′ of the electron beam 15 is deviated in the Y direction from the desired position 26X due to deflection distortion in the Y direction, the electron beam 15 irradiates the edge A1. Then, the X coordinate of the deflection position of the electron beam 15 in the X direction changes from XE1 to XE2, and the input deflection command amount acquired by the deflection command amount acquisition unit 72 in the X direction is affected.

Also, in the case where the deflection command amount supply unit 94 acquires the deflection command amount using the method described above with reference to FIG. 9 in step S106, each position detection mark 46 is moved to the electron beam for the same reason. It is preferable to have a linear edge portion in a direction perpendicular to the direction of measuring 15 deflection distortion amount positions or performing the deflection position correction described later.
Further, when the electron beam proximity exposure apparatus 1 performs deflection position distortion measurement and deflection position correction in the X direction and the Y direction shown in FIG. 7A, for example, the position detection marks 46 are respectively in the Y direction and It is preferable to have a linear edge in the X direction.

  By the way, each deflection command amount acquired by the deflection command amount acquisition unit 72 when the secondary reflected electrons generated by actually irradiating each position detection mark 46 with the electron beam 15 are detected are the main deflector 21, 22 is different from the deflection command amount stored in the memory 93 or the internal memory of the deflection command amount supply unit 94 in advance corresponding to the position of each position detection mark 46.

Accordingly, in step S <b> 109, the comparison unit 73 determines which position of each position detection mark 46 stored in the memory 93 corresponds to each deflection command amount acquired by the deflection command amount acquisition unit 72.
When the amount of deflection distortion that can be generated by the main deflectors 21 and 22 is smaller than the arrangement interval of the position detection marks 46 and the size of the position detection marks 46, the comparison unit 73 performs a deflection command amount acquisition unit 72. The deflection command amount acquired by the deflection command amount acquisition unit 72 when the deflection command amount acquired by the above is within a certain error range ΔW from the deflection command amount determined in advance corresponding to the position of the position detection mark 46. It is determined that the command amount corresponds to the position detection mark 46 and corresponds to a deflection command amount determined in advance corresponding to the position of the position detection mark 46. This method will be described with reference to FIGS. 11 (A) and 11 (B).

  FIG. 11A shows a case where a certain deflection command amount acquired by the deflection command amount acquisition unit 72 is within a certain error range ΔW from a deflection command amount determined in advance corresponding to the position of a certain position detection mark 46. It is explanatory drawing of. For example, the method described above with reference to FIG. 8 is used to acquire the deflection command amount.

The X coordinates of the edge portions A1 and A2 are used as position information data regarding the X direction of the position detection mark 46, and deflection command amounts determined in advance corresponding to the X coordinates are X1 and X2. The comparison unit 73 reads out deflection command amounts X1 and X2 determined in advance corresponding to the positions of the position detection marks 46 in the X direction from the memory 93 or the internal memory of the deflection command amount supply unit 94.
On the other hand, the deflection command amount acquisition unit 72 acquires the deflection command amounts XD1 and XD2 as deflection command amounts when the position detection mark 46 is detected from the detection value waveform diagram of the electron detector shown in the lower part of FIG. .
At this time, as shown in FIG. 11A, the deflection command amounts XD1 and XD2 acquired by the deflection command amount acquisition unit 72 are determined from the deflection command amounts X1 and X2 determined corresponding to the position detection mark 46. If it is within the error range ΔW, the comparison unit 73 determines that each of the deflection command amounts X1 and X2 determined corresponding to the position of the position detection mark 46 is acquired by the deflection command amount acquisition unit 72. And XD2 are determined to correspond to each other.

  However, as shown in FIG. 11B, when a certain deflection command amount acquired by the deflection command amount acquisition unit 72 is not within a certain error range ΔW, the comparison unit 73 deflects the deflection command amount. The calculation of the distortion amount is stopped, and a signal for notifying the operator of the fact is generated and transmitted to the computer 91.

  When the deflection distortion amount that can be generated by the main deflectors 21 and 22 is larger than the arrangement interval of the position detection marks 46 and the size of the position detection marks 46, the deflection command amount acquired by the deflection command amount acquisition unit 72 is obtained. There is a possibility that the amount is closer to a different mark position than the position detection mark 46 that was irradiated with the electron beam 15 when it was acquired.

  Therefore, when measuring and correcting such deflection distortion of the main deflectors 21 and 22, it is preferable to provide each position detection mark 46 with a unique identification portion for each position detection mark 46. FIG. 12 shows an example of a position detection mark having an identification portion. Each of the position detection marks 46A to 46C includes notches 47A to 47C, which are identification parts unique to each mark.

Information necessary for associating and specifying each position detection mark from the secondary reflected electron images of the identification portions 47 </ b> A to 47 </ b> C of each position detection mark 46 is given in advance and stored in the memory 93.
On the other hand, the electron beam proximity exposure apparatus 1 arranges the output signal of the electron detector 71 on a two-dimensional plane based on the deflection command amount output from the deflection command unit supply unit 94 and performs secondary reflection of the position detection mark 46. An image processing unit 81 that generates an electronic image and a secondary reflected electron image of the position detection mark 46 generated by the image processing unit 81 are input, and each position detection mark is extracted from the secondary reflected electron images of the identification portions 47A to 47C. A mark position acquisition unit that reads information necessary for identification from the memory 93 and identifies which position detection mark is captured from the secondary reflected electron images of the identification portions 47A to 47C. 82.
Further, the mark position acquisition unit 82 determines whether each of the specified position detection marks corresponds to each of the deflection command amounts acquired by the deflection command amount acquisition unit 72 and stored in the memory 93. Information that can be determined based on the deflection command amount information included in the image information and that can identify each determined position detection mark is stored in the memory 93 in association with each deflection command amount acquired by the deflection command amount acquisition unit 72.

  The comparison unit 73 and the correction unit 74 refer to each position detection mark specifying information stored in the memory 93 in association with each deflection command amount acquired by the deflection command amount acquisition unit 72 by the mark position acquisition unit 82. The position detection mark corresponding to the amount is specified, and the position of the position detection mark and the deflection command amount determined in advance corresponding to the position are read from the memory 93.

FIG. 13 is a flowchart of an electron beam deflection position correction measuring method according to the present invention. Hereinafter, the deflection position measurement in the X direction will be described.
In steps S201 to S208, the main deflectors 21 and 22 are deflected positions of the electron beam 15 as in steps S101 to S108 of the electron beam deflection position distortion measuring method according to the present invention described with reference to FIG. Are moved along the locus 26X and the locus 26Y.
At this time, the deflection command amount acquisition unit 72 scans the position detection marks 46 </ b> A to 46 </ b> P positioned in the deflection regions of the main deflectors 21 and 22, and the electron detector 71 is generated from each position detection mark 46. When the secondary electrons are detected, the deflection command amount supply unit 94 acquires the X direction deflection command amount and the Y direction deflection command amount that have been input to the main deflectors 21 and 22.

  In step S206, the method in which the deflection command amount acquisition unit 72 acquires the X direction deflection command amount and the Y direction deflection command amount is the distortion measurement of the deflection position of the electron beam according to the present invention described with reference to FIG. Step S106 of the method is the same as that described with reference to FIGS. 8 and 9, and is omitted here to avoid duplication.

  FIG. 14 is an explanatory diagram of an electron beam deflection position correcting method according to the present invention. Each position detection mark 46 provided at each position in the deflection region of the main deflectors 21 and 22 is an ideal lattice according to its position information (for example, the positions of the corners of the position detection marks 46A to 46D shown in FIG. 8). 48 is defined. Each intersection of a vertical line and a horizontal line included in the lattice 48 indicates a position indicated by position information of each position detection mark 46. Here, for the sake of simplicity, as the positions indicated by the position information of the respective position detection marks 46, only the reference points PI1 to PI9 that are the points on the uppermost row are given reference numerals.

  When the electron detector 71 detects secondary electrons generated from the position detection marks 46 irradiated with the electron beam 15 through the steps S201 to S208, the X-direction deflections input to the main deflectors 21 and 22 are detected. The command amount and each Y-direction deflection command amount are acquired. The range of each X direction deflection command amount and each Y direction deflection command amount is indicated by a curved portion 28 shown outside the lattice 48 in FIG. Here, the deflection command amounts PD1 to PD9 correspond to the position information PI1 to PI9 of the position detection marks 46, respectively.

In step S <b> 209, the correction unit 74 reads from the memory 93 each deflection command amount acquired by the deflection command amount acquisition unit 72 in step S <b> 206 and stored in the memory 93.
Then, the correction unit 74 is the same as that performed by the comparison unit 73 in the method described above with reference to FIGS. 11 and 12 in the electron beam deflection position distortion measuring method according to the present invention in step S206. Each position detection mark 46 corresponding to each acquired deflection command amount is determined.
The correction unit 74 determines the deflection command amount stored in advance by the memory 93 or the deflection command amount supply unit 94 in correspondence with the position of each position detection mark 46 to each deflection command amount acquired in step S206. to correct.

  That is, as shown in FIG. 14, the correcting unit 74 sets each deflection command amount necessary for deflecting the electron beam 15 to the position (for example, PI1 to PI9) indicated by the position information of each position detection mark 46 in step S206. The obtained deflection command amounts PD1 to PD9 are corrected.

  In the above description, the method for measuring the distortion of the deflection position of the electron beam 15 and the method for correcting the deflection position using each position detection mark 46 formed on the measurement wafer 45 have been described. Instead of the position detection marks 46, a plurality of position detection marks (for masks) similar to the position detection marks 46 described above are formed on the exposure mask for measurement, and the deflection of the electron beam 15 is performed using them. The deflection position may be corrected by measuring position distortion. The measurement exposure mask on which the position detection mark (for mask) is formed is supported by a mask stage 36 as mask support means.

In this case, when the position data of each position detection mark (for mask) formed on the measurement mask is provided on the memory 93 and the identification portion 47 is provided for each position detection mark (for mask). Stores information necessary for specifying the position detection mark from the secondary reflected electron image of the identification portion 47.
The secondary electron detector 71 is arranged on a measurement exposure mask supported by the mask stage 36 in place of the secondary electrons 17 generated by irradiating the position detection mark formed on the measurement wafer 45. Secondary electrons generated by irradiating the position detection mark (for mask) formed on the substrate are detected.

  Further, the imaging unit 83 replaces the alignment mark whose position relative to the position detection mark formed on the measurement wafer 45 is known with a position detection mark (for mask) formed on the measurement exposure mask. An alignment mark whose relative position is known is imaged. The alignment unit 84 uses a position detection mark (for mask) on the measurement exposure mask as a predetermined deflection region of the main deflectors 21 and 22 based on the image captured by the image capturing unit 83 and the position information of the mask stage 36 at the time of capturing. Position it at a known location.

  Further, the image processing unit 81 arranges the output signal of the electron detector 71 on a two-dimensional plane based on the deflection command amount output from the deflection command amount supply unit 94, and a position detection mark on the measurement exposure mask. A secondary reflected electron image (for mask) is generated, and the mark position acquisition unit 82 inputs the secondary reflected electron image and performs secondary reflection of the identification portion of the position detection mark (for mask) included therein. A corresponding position detection mark (for mask) is specified from the electronic image.

  The deflection position distortion measurement method when the position detection mark is provided on the measurement exposure mask, and the deflection position correction method include the deflection position distortion measurement method when the position detection mark 46 is provided on the measurement wafer 45, In the above description, the measurement wafer 45 is used as a measurement exposure mask, the position detection mark 46 is used as a position detection mark (for mask), the electrostatic chuck 43 is used as a mask chuck, and XY. Since it can be easily understood by replacing the stage 44 with the mask stage 36, description thereof will be omitted.

It is a block diagram of an electron beam proximity exposure apparatus. It is operation | movement explanatory drawing of a scanning means. It is explanatory drawing of the scanning method of an electron beam. It is explanatory drawing of mask distortion correction. It is a schematic block diagram of the electron beam exposure apparatus which concerns on the Example of this invention. 3 is a flowchart of a method for measuring distortion of an electron beam deflection position according to the present invention. (A) is a top view of the reference wafer when the electron beam is scanned in the X direction, and (B) is a top view of the reference wafer when the electron beam is scanned in the Y direction. (A) is a diagram showing the positional relationship between an electron beam irradiation position and a position detection mark when the electron beam is scanned in the X direction, and (B) is an output signal waveform diagram of the electron detector at that time. (C) is an output signal waveform diagram of the electron detector when the electron beam is scanned in the Y direction, and (D) is a diagram showing the positional relationship between the electron beam locus and the position detection mark at that time. (A) is a figure which shows the positional relationship of an electron beam irradiation position and a position detection mark when scanning an electron beam with a diameter larger than a position detection mark, (B) is the output signal of the electron detector at that time It is a wave form diagram, (C) is a primary differential wave form figure of (B). (A) is a top view of a position detection mark having a straight portion edge in the Y direction, and is a top view of a position detection mark having no straight portion edge in the Y direction. (A) is explanatory drawing when the position detection mark corresponding to the detection signal of an electron detector can be specified, (B) is explanatory drawing when the position detection mark corresponding to the detection signal of an electron detector cannot be specified. is there. It is a figure which illustrates the Example of the position detection mark which has an identification part. 3 is a flowchart of a method for correcting the deflection position of an electron beam according to the present invention. It is explanatory drawing of the deflection position correction method of the electron beam which concerns on this invention.

Explanation of symbols

8 ... Chamber 10 ... Electron tube (column)
DESCRIPTION OF SYMBOLS 12 ... Electron gun 13 ... Scanning means 14 ... Electron beam source 15 ... Electron beam 16 ... Irradiation lens 21, 22 ... Main deflector 30 ... Mask 40 ... Sample 43 ... Electrostatic chuck 44 ... XY stage 45 ... Deflection distortion measuring wafer 46 ... Position detection marks 51 and 52 ... Sub deflector 72 ... Deflection command amount acquisition unit 73 ... Comparison unit 74 ... Correction unit

Claims (19)

An electron beam source for generating an electron beam, a mask having a mask pattern corresponding to an exposure pattern, and each of the electron beams according to an input of each deflection command amount predetermined corresponding to each position on the mask An electron beam exposure apparatus that irradiates the exposure pattern on the surface of the sample with the electron beam that has passed through the mask by irradiating the electron beam onto the mask. Position detection mark support means for positioning and supporting a position detection mark that generates secondary electrons when irradiated with the electron beam at a known position in the deflection region of the electron beam by the deflection means;
An electron detector for detecting secondary electrons generated when the position detection mark is irradiated with the electron beam;
A deflection command amount acquisition means for acquiring a deflection command amount input to the deflection means upon detection of the secondary electrons;
Correction means for correcting a predetermined deflection command amount corresponding to the position of the position detection mark to the obtained deflection command amount;
An electron beam exposure apparatus comprising: A plurality of the position detection marks are provided,
The deflecting means scans the electron beam on each position detection mark,
The deflection command amount acquisition means acquires the deflection command amounts at the time of detection of the secondary electrons generated from the position detection marks, respectively.
2. The electron beam exposure apparatus according to claim 1, wherein the correction unit corrects each deflection command amount predetermined corresponding to the position of each position detection mark to each of the acquired deflection command amounts. 3. At least a part of the edge of the position detection mark has a linear shape in a predetermined direction,
The deflecting means scans the electron beam in the vertical direction of the predetermined direction on the edge of the position detection mark,
The deflection command amount acquisition means obtains the deflection command amount corresponding to the position of the edge in the vertical direction of the predetermined direction based on a change in the detection value of the secondary electrons accompanying a change in the scanning position of the electron beam. The electron beam exposure apparatus of Claim 1 or 2 to acquire. The position detection mark is a heavy metal or a step formed on the surface of the semiconductor wafer,
The electron beam exposure apparatus according to claim 1, wherein the position detection mark support means is a semiconductor wafer support means. The position detection mark is a heavy metal or a step formed on the surface of the mask,
The electron beam exposure apparatus according to claim 1, wherein the position detection mark support unit is a mask support unit. The electron beam generated by the electron beam source is applied to each position on a mask having a mask pattern corresponding to the exposure pattern, and the electron beam is applied to each position according to each predetermined deflection command amount input corresponding to each position. Measurement of distortion of the deflection position of the electron beam by the deflection means in the electron beam exposure in which the exposure pattern is exposed on the sample surface with the electron beam which has been deflected and irradiated by the deflection means and passed through the mask. A method,
A position detection mark support step for positioning and supporting a position detection mark that generates secondary electrons by being irradiated with the electron beam at a known position in the deflection region of the electron beam by the deflection means;
An electron beam scanning step of changing and inputting a deflection command amount to the deflection means, and scanning the electron beam on the position detection mark;
An electron detection step of detecting secondary electrons generated when the position detection mark is irradiated with the electron beam;
A deflection command amount acquisition step of acquiring a deflection command amount input to the deflection means when detecting the secondary electrons;
A comparison step for obtaining a difference between the deflection command amount determined corresponding to the position of the position detection mark and the deflection command amount acquired in the deflection command amount acquisition step;
A method for measuring the distortion of the deflection position of an electron beam comprising: In the electron beam scanning step, the electron beam is scanned on each of the plurality of position detection marks provided,
The deflection command amount acquisition step acquires each of the deflection command amounts at the time of detection of the secondary electrons generated from the position detection marks,
In the comparison step, a difference between each deflection command amount predetermined in correspondence with the position of each position detection mark and each deflection command amount acquired in the deflection command amount acquisition step is calculated. The distortion measuring method of the deflection position of the electron beam according to claim 6 to be obtained. At least a part of the edge of the position detection mark has a linear shape in a predetermined direction,
In the deflection command amount acquisition step, when the deflecting means scans the electron beam in the vertical direction of the predetermined direction on the edge portion of the position detection mark, a change in the detected value of the secondary electrons accompanying this is detected. 8. The method according to claim 6, wherein the deflection command amount corresponding to the position of the edge in the vertical direction of the predetermined direction is acquired. The position detection mark is a heavy metal or a step formed on the surface of the semiconductor wafer,
9. The method for measuring distortion of an electron beam deflection position according to claim 6, wherein the position detection mark support step supports a semiconductor wafer on which the position detection mark is formed. The position detection mark is a heavy metal or a step formed on the surface of the mask,
The method for measuring distortion of an electron beam deflection position according to any one of claims 6 to 8, wherein the position detection mark support step supports a mask on which the position detection mark is formed.   9. The method of measuring distortion of an electron beam deflection position according to claim 6, wherein a heavy metal portion or a step portion used as the position detection mark is formed on a surface.   9. The exposure mask according to claim 6, wherein a heavy metal portion or a step portion used as the position detection mark is formed on a surface. The electron beam generated by the electron beam source is applied to each position on a mask having a mask pattern corresponding to the exposure pattern, and the electron beam is applied to each position according to each predetermined deflection command amount input corresponding to each position. A method of correcting the deflection position of an electron beam by the deflection means in electron beam exposure in which the exposure pattern is exposed on the surface of a sample with the electron beam that has been deflected and irradiated by a deflection means that deflects the position and passed through the mask. There,
A position detection mark support step for positioning and supporting a position detection mark that generates secondary electrons by being irradiated with the electron beam at a known position in the deflection region of the electron beam by the deflection means;
An electron beam scanning step of changing and inputting a deflection command amount to the deflection means, and scanning the electron beam on the position detection mark;
An electron detection step of detecting secondary electrons generated when the position detection mark is irradiated with the electron beam;
A deflection command amount acquisition step of acquiring a deflection command amount input to the deflection means when detecting the secondary electrons;
A correction step of correcting a predetermined deflection command amount corresponding to the position of the position detection mark to the obtained deflection command amount;
A method for correcting the deflection position of an electron beam. In the electron beam scanning step, the electron beam is scanned on each of the plurality of position detection marks provided,
The deflection command amount acquisition step acquires each of the deflection command amounts at the time of detection of secondary electrons generated from the position detection marks,
The deflection position of the electron beam according to claim 13, wherein the correcting step corrects each deflection command amount predetermined corresponding to the position of each position detection mark to each acquired deflection command amount. Correction method. At least a part of the edge of the position detection mark has a linear shape in a predetermined direction,
In the deflection command amount acquisition step, when the deflecting unit scans the edge of the position detection mark with the electron beam in the vertical direction of the predetermined direction, a change in the detected value of the secondary electrons accompanying this is performed. 15. The electron beam deflection position correction method according to claim 13, wherein the deflection command amount corresponding to the position of the edge is obtained in the vertical direction of the predetermined direction. The position detection mark is a heavy metal or a step formed on the surface of the semiconductor wafer,
16. The electron beam deflection position correction method according to claim 13, wherein the position detection mark support step supports a semiconductor wafer on which the position detection mark is formed. The position detection mark is a heavy metal or a step formed on the surface of the mask,
The electron beam deflection position correction method according to any one of claims 13 to 15, wherein the position detection mark support step supports a mask on which the position detection mark is formed.   16. The method for correcting a deflection position of an electron beam according to claim 13, wherein a heavy metal portion or a step portion used as the position detection mark is formed on a surface.   16. The electron beam deflection position correction method according to claim 13, wherein a heavy metal portion or a step portion used as the position detection mark is formed on a surface.

Images