JP2011002487A - Method of manufacturing diffraction grating, diffraction grating, and spectral analysis device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diffraction grating reducing the occurrence of abnormal peaks of diffraction light occurring by repeated exposure to allow sharp spectroscopy with few abnormal peaks, and to provide a highly precise spectral analysis device by using the diffraction grating.SOLUTION: In manufacturing a diffraction grating with a fixed pitch by repeated exposure, exposure is repeated while setting a relationship between the pitch dimension of the diffraction grating to be manufactured and a repeated exposure cycle with a small-angle deflection to achieve a ratio P/S of 0.1 or higher between the pitch dimension P to be exposed and the repeated exposure cycle S with the small-angle deflection, the occurrence of the abnormal peaks of diffraction light occurring by exposure is reduced, and consequently, the diffraction grating allowing sharp spectroscopy with few abnormal peaks is obtained.

Description

  The present invention relates to a method for manufacturing a diffraction grating used for spectroscopic analysis for analyzing a component of a sample, a diffraction grating, and a spectroscopic analysis apparatus using the diffraction grating.

In recent years, the field of using spectroscopic analysis covers a wider range from the bio field to medical and semiconductor fields, and requires highly accurate measurement. The measurement accuracy of this spectroscopic analysis is determined by the accuracy of the diffraction grating used for spectroscopy.
However, it is difficult to produce a diffraction grating having a wide area of several centimeters or more with uniform accuracy and a fine pitch dimension. On the other hand, in the microfabrication technology for semiconductor elements, a technology has been developed that realizes microfabrication in a narrow region of several centimeters or less and repeats that region repeatedly. Therefore, Patent Document 1 proposes a method for manufacturing a diffraction grating by repeated exposure, in which a fine processing technique of a semiconductor element is applied to optical fiber processing which is an optical element having a similar technical problem.

JP 2001-242313 A

However, the spectroscopic analysis using the diffraction grating produced by the conventional repeated exposure as described above has the following problems.
The light 15 from the light source 1 of the spectroscopic analysis apparatus shown in FIG. 1 passes through the slit 2 and is then split by the diffraction grating 3 so that only the diffracted light 16 having a specific wavelength passes through the slit 4 and is used for analysis. . When a diffraction grating produced by repeated exposure is used for spectroscopic analysis, a positional error occurs between adjacent diffraction patterns at the time of repeated exposure. Therefore, as shown in FIG. In addition to the diffracted light 100, the extraordinary light 101 reflecting the repeated pitch size of repeated exposure is generated around the diffracted light 100 that is originally required for analysis. As a result, abnormal light is also reflected in the sample analysis, so that the analysis accuracy is deteriorated. Therefore, in the diffraction grating as shown in Patent Document 1, the exposure is divided into a plurality of times, the repeated position is shifted and the repeated exposure is performed multiple times, and the adjacent diffraction grating pattern misalignment error is repeated between the repeated patterns. A method is considered to alleviate the phenomenon as a whole pattern.

Such a diffraction grating has the following problems.
When repeated exposure is performed in a multiple manner and an adjacent diffraction grating pattern misalignment error between repetitive patterns is alleviated in the entire pattern, the misalignment error between the multiples varies between the multiples as shown in FIG. Decreases compared to the case where multiple exposure is not used. However, the peak wavelength of extraordinary light is the same as the peak wavelength of conventional extraordinary light that does not use multiple exposure because it is due to the pitch size of repeated exposure. For this reason, since the intensity of the extraordinary light at the wavelength position closer to the original diffracted light wavelength is higher, the extraordinary light at the wavelength position near the diffracted light wavelength cannot be eliminated even by using multiple exposure. In order to perform highly accurate analysis, it is necessary to suppress the intensity of the extraordinary light at a wavelength position close to the diffracted light wavelength to 10 ⁻⁵ or less compared to the intensity of the diffracted light used for the original analysis.

  A main object of the present invention is to provide a method for producing a fine and uniform diffraction grating in which generation of abnormal light is suppressed, a diffraction grating, and a spectroscopic analyzer using the same.

  The diffraction grating of the present invention and the spectroscopic analysis apparatus using the same are the diffraction gratings produced by repeated exposure applying the microfabrication technology of semiconductor elements. It is characterized by suppressing the influence on the analysis accuracy of abnormal light by shifting to a wavelength position away from the light wavelength.

The principle of shifting the peak wavelength of the extraordinary light to a wavelength position away from the wavelength of the diffracted light for analysis will be described below. If the wavelength of the extraordinary light is λ _G , the wavelength of the diffracted light λ _p , the pitch dimension P of the diffraction grating, the pitch dimension S of repeated exposure, the diffraction order n of the diffracted light, and the order m of the extraordinary light, There is a relationship of the following equation (1) between the wavelength λ _G and the wavelength λ _p of the diffracted light of the diffraction grating.

λ _G = λ _p (1 ± nP / mS) (1)

Here, since the wavelength λ _p of the diffraction light of the diffraction grating, the pitch dimension P of the diffraction grating, the diffraction order n of the diffraction light, and the order m of the extraordinary light are predetermined values, the value of the pitch dimension S for repeated exposure is adjusted. Thus, it is possible to adjust the appearance wavelength of abnormal light. Also, since the peak intensity of extraordinary light is superimposed on the intensity attenuation of the diffracted light based on the Fraunhofer diffraction principle of a general diffraction grating, the extraordinary light increases depending on the wavelength difference as the distance from the wavelength of the diffracted light increases. Its peak intensity is attenuated. That is, the diffraction grating of the present invention and the spectroscopic analysis apparatus using the same set the wavelength of the extraordinary light to the original diffracted light wavelength by setting the pitch dimension of the repeated exposure to an appropriate value in the diffraction grating manufactured by repeated exposure. It is characterized by suppressing the influence on the analysis accuracy of extraordinary light by shifting to a wavelength away from the light.

  The method for producing a diffraction grating according to the present invention is a method for producing a diffraction grating having a constant pitch by repeated exposure, wherein the ratio P / S between the pitch dimension P of the diffraction grating and the pitch dimension S of the repeated exposure repeated region is 0.1. It sets so that it may become above, and repeats exposure.

  Also, the diffraction grating manufacturing method of the present invention is a method of manufacturing a diffraction grating with a constant pitch by repeated exposure, and the ratio P / S between the pitch dimension P of the diffraction grating and the pitch dimension S of the repeated exposure repeated region is 0. Repeat exposure is performed by using multiple exposure that is set to be 1 or more and the boundary position of repeated exposure is changed.

  In addition, the method for producing a diffraction grating according to the present invention is a method for producing a diffraction grating having a constant pitch used for spectroscopic analysis by repeated exposure. Repeated exposure is performed by setting the repeat pitch dimension of the repeat region so that the absolute value becomes 1/10 or more of the spectral analysis wavelength.

Furthermore, the method for producing a diffraction grating according to the present invention is a method for producing a diffraction grating with a constant pitch by repeated exposure in units of line and space patterns, and an electron that forms a line and space pattern with a pitch dimension P of the diffraction grating to be exposed. The electron beam exposure is performed by repeating the small angle deflection by setting the ratio P / S of the small angle deflection of the beam to the repeated exposure cycle S to be 0.1 or more.
At this time, the length of the line-and-space pattern as a unit of exposure may be made longer than the length in the direction perpendicular to the grating line of the diffraction grating.

  In the diffraction grating of the present invention, the ratio P / S between the pitch dimension P of the diffraction grating and the pitch dimension S of the repeated region is 0.1 or more in a constant pitch diffraction grating manufactured by repeated exposure. .

  The spectroscopic analyzer of the present invention is a spectroscopic analyzer that analyzes a component of a sample from its transmission characteristics after diffusing light from a light source with a diffraction grating, and producing the diffraction grating by repeated exposure. A diffraction grating having a constant pitch, in which a ratio P / S between the pitch dimension P of the diffraction grating and the pitch dimension S of the repeating region is 0.1 or more, is used.

  According to the present invention, a fine and uniform diffraction grating can be realized by a diffraction grating produced by repeated exposure applying a microfabrication technique for semiconductor elements, and the pitch dimension of repeated exposure can be set to an appropriate value. By shifting the wavelength of the extraordinary light to a wavelength away from the original diffracted light wavelength, the intensity of the extraordinary light can be greatly reduced, or it can be moved out of the wavelength range that does not affect the measurement accuracy. And by realizing a diffraction grating that suppresses the influence on the analysis accuracy of extraordinary light, a method for producing a fine and uniform diffraction grating that suppresses the generation of extraordinary light, the diffraction grating, and spectroscopic analysis using the same Equipment can be provided.

It is the schematic which showed the spectroscopic analyzer of this invention. It is a manufacturing process flowchart which shows the manufacturing method of the diffraction grating of this invention. It is the schematic of the electron beam exposure apparatus used for preparation of a diffraction grating. It is the schematic of the electron beam exposure method of the conventional diffraction grating. It is a spectral characteristic figure of the conventional diffraction grating. It is a spectral characteristic figure of the conventional diffraction grating. It is a figure which shows the spectroscopic measurement result of the conventional spectroscopic analyzer. It is the schematic of the electron beam multiple exposure method of a diffraction grating. It is the schematic of the electron beam exposure method of the diffraction grating in the 1st Example of this invention. It is a spectral characteristic figure of the diffraction grating in the 1st example of the present invention. It is a figure which shows the spectroscopic measurement result of the spectroscopic analyzer in the 1st Example of this invention. It is the schematic of the electron beam exposure method of the diffraction grating in the 2nd Example of this invention. It is the schematic of the electron beam exposure method of the diffraction grating in the 3rd Example of this invention. It is a spectral characteristic figure of the diffraction grating in the 3rd example of the present invention. It is a figure which shows the relationship of the intensity | strength of abnormal light with respect to ratio P / S of the pitch dimension P of a diffraction grating, and the repeated exposure period S.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, FIG. 1 is a schematic diagram of a spectroscopic analysis apparatus according to the present invention.
(1) The light 15 generated from the light source 1 passes through the slit 2 and is incident on the diffraction grating 3, and then is split by the diffraction grating. At this time, the wavelength of the diffracted light 16 required for analysis is determined by the pitch dimension of the diffraction grating 3 and the angle of the diffraction grating.
(2) The diffracted light 16 selected as described above is split into two light waves by the mirrors 5, 7, 8 and the half mirror 6.
(3) One of the two light waves is incident on the analysis sample cell 10, the other light is incident on the reference cell 9, and each light is depleted through the lenses 11, 12, and then each detector 13, At 14 the intensity is measured.
(4) The intensity measured by the two detectors is compared and referenced by the data analysis unit, and recorded as the transmission intensity of the analysis sample in the data analysis unit.
(5) From the diffraction wavelength determined by the pitch size of the diffraction grating of the item (1) and the angle of the diffraction grating and the transmission intensity of the analysis sample of the item (4), the transmission intensity characteristic of the analysis sample for each diffraction wavelength is Recorded in the data analysis unit.
(6) The components of the analysis sample are analyzed by analyzing the above data.
As described above, the spectral characteristic accuracy of the present apparatus is determined by the spectral characteristic of the diffraction grating. That is, the diffracted light from the diffraction grating is required to have a steep wavelength characteristic and an optical characteristic that does not have an abnormal peak around the wavelength.

As shown in FIG. 2, the diffraction grating is manufactured by the following process.
(1) A resist 18 is applied on the silicon substrate 17, and (2) a line and space pattern having a constant pitch dimension is exposed with an electron beam, and then the resist is developed. Next, (3) a line and space pattern having a constant pitch dimension is transferred to the silicon substrate by dry etching using this resist as a mask. Thereafter, (4) the resist is removed, and (5) a metal thin film 19 such as Al is deposited on the surface to complete the diffraction grating. Although it is possible to directly attach this diffraction grating to the spectroscopic analysis apparatus of FIG. 1, the same optical characteristics can be obtained even when a replica is manufactured using this diffraction grating as a mold and is attached to the spectroscopic analysis apparatus.
Next, the conventional exposure method will be described with reference to FIGS. 3 and 4 by taking the exposure of a diffraction grating having a pitch dimension of 0.833 μm and a 50 mm square as an example of the electron beam exposure method by the repeated exposure method which is a feature of the present invention. First, the electron beam 21 generated from the electron gun 20 passes through the first mask 22 and is then irradiated onto the second mask 27 by the transfer lenses 23 and 25, and the aperture 26 is controlled by the pattern dimension control system 36 and the variable shaping deflector 24. After the beam is formed into a desired beam size, it is reduced by the reduction lenses 28 and 29 and the objective lenses 32 and 33. The electron beam is irradiated to a desired position on the substrate 34 by combining the small angle deflection control system 37 and the small angle deflector 30, and the large angle deflection control system 38 and the large angle deflector 31. The maximum deflection areas of the small angle deflector 30 and the large angle deflector 31 are 60 μm square and 1 mm square, respectively. By combining the movement of the stage movement control system 39 and the stage 35 at a position outside the area of the deflector, exposure of an arbitrary area is possible. For exposure of diffraction gratings with a pitch size of 0.833μm and a 50mm square, the maximum deflection area of the small-angle deflector and large-angle deflector is conventionally set to be large, and the number of times of movement using the deflection and the stage is reduced. As a result, the exposure time is shortened. Therefore, as shown in FIG. 4, a line and space pattern 42 having a pitch size of 0.833 μm is exposed within a 40 μm square 40 by controlling the beam position with a small angle deflector 30, and a region beyond that is exposed by a large angle deflector. Similarly, the center of the small-angle deflection is shifted by 40 μm, and a line-and-space pattern with a pitch size of 0.833 μm is exposed within the 40-μm square 41 by controlling the beam position with the small-angle deflector. After repeating this process vertically and horizontally to the maximum 1 mm square in the large angle deflection area, the stage is moved 1 mm horizontally, and the adjacent 1 mm square is similarly exposed by small and large angle deflections. A 0.833 μm line and space pattern is exposed on the entire surface of 50 mm square. In other words, the entire surface of 50 mm square was exposed by repeated exposure of 40 μm square in the vertical and horizontal directions 1250 times each. The exposed substrate is transferred with a line and space pattern having a pitch size of 0.833 μm to the substrate according to the manufacturing process of FIG.

  When this diffraction grating was mounted on a spectrometer and its spectral characteristics were examined, the spectral characteristics shown in FIG. 5 were obtained. The horizontal axis represents the spectral wavelength, and the vertical axis represents the spectral intensity. An anomalous peak 101 reflecting the repeated exposure of the small-angle deflection derived from the equation (1) at the center of the diffracted light 100 from the line-and-space pattern with a pitch size of 0.833 μm in the vicinity of the diffraction wavelength of 200 nm reflects the 40 μm period repeated diffraction wavelength. Appeared at a cycle of 0.02 times (0.833 / 40 = 0.02). Ten abnormal peaks were included in the wavelength range of ± 10 nm with respect to the original peak with a diffraction wavelength of 200 nm, and the maximum intensity of the abnormal peak was 90% or more of the diffracted light. Therefore, when this diffraction grating was mounted on the spectroscopic analyzer shown in FIG. 1 and a sample was mounted on the sample cell shown in FIG. 1, component analysis was performed, and the absorption spectrum shown in FIG. 7 was obtained. Although the absorption spectrum peak was observed, the detailed spectrum peak could not be sufficiently separated, and the component analysis of the sample could not be performed.

  Therefore, as a conventional method, multiple exposure was performed in electron beam exposure as shown in FIG. That is, the irradiation amount per time was set to 1/2 and divided into two times, and the second small-angle deflection position 44 was shifted 20 μm laterally with respect to the small-angle deflection position 43 of the first exposure, and repeated exposure was performed. When the diffraction grating produced by this exposure was mounted on a spectrometer and its spectral characteristics were examined, the spectral characteristics shown in FIG. 6 were obtained. The horizontal axis represents the spectral wavelength, and the vertical axis represents the spectral intensity. Similar to FIG. 5, anomaly reflecting 40 μm period repeated exposure of small angle deflection derived from equation (1) around the diffraction light 100 from a line and space pattern with a pitch of 0.833 μm near the diffraction wavelength of 200 nm. Peak 101 appeared at a period of 0.02 times the diffraction wavelength (0.833 / 40 = 0.02), but the maximum intensity of the abnormal peak was 80% of the diffracted light. For this reason, this diffraction grating was mounted on the spectroscopic analyzer shown in FIG. 1 and a sample was mounted on the sample cell shown in FIG. 1, and component analysis was performed. Could not be analyzed.

Next, in Example 1 of the present invention, the relationship between the line-and-space pattern 47 having a pitch dimension (P) of 0.833 μm and the repeated exposure cycle (S) of small-angle deflection in the electron beam exposure as shown in FIG. The exposure was performed by setting the ratio of the pitch size to be exposed and the repeated exposure cycle of small-angle deflection to 0.1 or more in equation (1). That is, when exposing a diffraction grating having a pitch dimension of 0.833 μm and a 50 mm square, a line-and-space pattern 47 having a pitch dimension of 0.833 μm within a 5 μm square 45 is controlled by a small-angle deflector 30 as shown in FIG. After exposure, the large-angle deflector 31 shifts the small-angle deflection center by 5 μm to the area beyond it, and similarly controls the beam position of the line-and-space pattern with a pitch dimension of 0.833 μm by the small-angle deflector 30. To expose. After repeating this vertically and horizontally to the maximum 1 mm square of the large angle deflection area, the stage 35 is moved 1 mm horizontally and the adjacent 1 mm square is similarly exposed by small and large angle deflections. A 0.833 μm line and space pattern is exposed on the entire surface of 50 mm square. In other words, the entire surface of 50 mm square was exposed by repeated exposure of 5 μm square in the vertical and horizontal directions 10,000 times each. When the diffraction grating produced by this exposure was mounted on a spectrometer and the spectral characteristics were examined, the spectral characteristics shown in FIG. 10 were obtained. The horizontal axis represents the spectral wavelength, and the vertical axis represents the spectral intensity. No abnormal peak was observed near the diffraction wavelength of 200 nm. Anomalous peak reflecting repeated exposure of 5 μm period of small angle deflection derived from equation (1) should appear near 230 nm, 0.17 times the diffraction wavelength (0.833 / 5 = 0.17), but far from the diffraction wavelength of 200 nm Therefore, the maximum intensity of the abnormal peak was 10 ⁻⁵ or less of the diffracted light. Therefore, when the diffraction grating of the present invention is mounted on the spectroscopic analysis apparatus of FIG. 1 and a sample is mounted on the sample cell of FIG. 1, component analysis is performed. As shown in FIG. 11, the absorption spectrum clearly shows all wavelength regions. The spectral peaks can be separated and the sample can be analyzed with high accuracy.

Next, the exposure method according to the second embodiment of the present invention will be described by taking exposure of a 50 mm square line-and-space pattern having a pitch size of 0.833 μm as an example in the electron beam exposure. As shown in FIG. 12, in the relationship between the line-and-space pattern 50 having a pitch dimension (P) of 0.833 μm to be exposed and the repeated exposure period (S) of small angle deflection, the pitch dimension to be exposed and the grating of the diffraction grating in the equation (1) The exposure was performed by setting the ratio of the small-angle deflection repeated exposure cycle in the direction perpendicular to the straight line to 0.1 or more. That is, when exposing a diffraction grating having a pitch size of 0.833 μm and a 50 mm square, a line and space pattern 50 having a pitch size of 0.833 μm within a horizontal 5 μm × vertical 20 μm square 48 as shown in FIG. Exposure is controlled and the area beyond that is shifted by 5 μm laterally in the direction perpendicular to the grating line of the diffraction grating by the large-angle deflector 31, and similarly 5 μm wide × 20 μm long 49 squares with a pitch size of 0.833 μm The line and space pattern is exposed by controlling the beam position with the small-angle deflector 30. Similarly, the vertical direction is shifted 20 μm vertically and repeatedly exposed to the maximum 1 mm square of the large angle deflection area, then the stage 35 is moved 1 mm horizontally to similarly expose the adjacent 1 mm square by small angle and large angle deflection. By repeating the above, a line and space pattern having a pitch size of 0.833 μm is exposed on the entire surface of 50 mm square. That is, the entire surface of 50 mm square was exposed by repeated exposure at a pitch of 5 μm in the horizontal direction and 10,000 times at a pitch of 2500 μm in the vertical direction at a pitch of 20 μm.
When the diffraction grating produced by this exposure was mounted on a spectrometer and its spectral characteristics were examined, the same spectral characteristics as in FIG. 10 were obtained. The horizontal axis represents the spectral wavelength, and the vertical axis represents the spectral intensity. No abnormal peak was observed near the diffraction wavelength of 200 nm. Similar to the case described in Example 1, the abnormal peak reflecting the repeated exposure of 5 μm period of small-angle deflection in the direction perpendicular to the grating line of the diffraction grating is around 230 nm, which is 0.17 times the diffraction wavelength (0.833 / 5 = 0.17). Although it should appear, since it is away from the diffraction wavelength of 200 nm, the maximum intensity of the abnormal peak is 10 ⁻⁵ or less of the diffracted light. For this reason, this diffraction grating was mounted on the spectroscopic analyzer shown in FIG. 1 and a sample was mounted on the sample cell shown in FIG. 1, and component analysis was performed. As shown in FIG. The sample can be separated and the high-accuracy component analysis of the sample is possible.
As described above, the repetition pitch in the vertical direction that does not affect the diffraction phenomenon is set to 20 μm, so that the optical characteristics are not changed compared to Example 1, and the exposure is repeated 2500 times at a pitch of 20 μm in the vertical direction. Compared to Example 1, a diffraction grating could be fabricated with an exposure time of one quarter. In other words, the exposure time can be reduced by increasing the length of the diffraction grating in the grating linear direction compared to the length of the line and space pattern 50 as a unit of exposure in the direction perpendicular to the diffraction grating grating straight line. Can be shortened.

Similarly, the exposure method according to the third embodiment of the present invention will be described by taking exposure of a diffraction grating having a 50 mm square line-and-space pattern with a pitch size of 0.555 μm as an example. In the relationship between the pitch dimension and the repeated exposure cycle of small angle deflection, exposure is performed such that the ratio of the pitch size (P) to be exposed and the repeated exposure cycle (S) of small angle deflection in equation (1) is 0.1 or more. Went. That is, when exposing a diffraction grating having a pitch size of 0.555 μm and a 50 mm square, a line and space pattern 53 having a pitch size of 0.555 μm in a 5 μm square 51 is controlled by a small angle deflector 30 as shown in FIG. After exposure, the large-angle deflector 31 shifts the small-angle deflection center by 5 μm laterally, and similarly controls the beam position of the 5 μm-square 52 and line-and-space pattern with a pitch size of 0.555 μm by the small-angle deflector 30. To expose. After repeating this vertically and horizontally to the maximum 1 mm square of the large angle deflection area, the stage 35 is moved 1 mm horizontally and the adjacent 1 mm square is similarly exposed by small and large angle deflections. A line and space pattern of 0.555 μm is exposed on the entire surface of 50 mm square. In other words, the entire surface of 50 mm square was exposed by repeated exposure of 5 μm square in the vertical and horizontal directions 10,000 times each. The diffraction grating produced by this exposure was mounted on a spectrometer and the spectral characteristics were examined. As shown in FIG. 14, no abnormal peak was observed near the diffraction wavelength of 200 nm. Anomalous peak reflecting repeated exposure of 5μm period of small angle deflection derived from equation (1) should appear near 230nm, 0.11 times the diffraction wavelength (0.555 / 5 = 0.11), but far from the diffraction wavelength 200nm Therefore, the maximum intensity of the abnormal peak was 10 ⁻⁵ or less of the diffracted light.
Further, in the electron beam exposure, multiple exposure was performed as follows in the same manner as in FIG. In other words, exposure was performed by setting the irradiation amount per time to 1/2 and dividing the second small angle deflection position by 2.5 μm horizontally with respect to the small angle deflection position of the first exposure. . When the diffraction grating produced by this exposure was mounted on a spectrometer and its spectral characteristics were examined, the maximum intensity of the abnormal peak was further improved to 10 ⁻⁶ or less of the diffracted light.

  According to the embodiment of the present invention, it is possible to produce a line and space pattern with a pitch dimension of 1 μm or less with high accuracy by producing a diffraction grating using repetitive exposure by electron beam exposure used for semiconductor microfabrication. Since it is possible to realize a diffraction grating that suppresses the occurrence of an abnormal peak of diffracted light that occurs due to repeated exposure and is capable of performing spectroscopic analysis with a steep and few abnormal peak, high-accuracy spectroscopic analysis can be performed by using this diffraction grating. . Furthermore, by using multiple exposure in combination, the intensity of the abnormal peak can be reduced, and a diffraction grating capable of performing spectroscopy with less influence of the abnormal peak can be realized.

  Although the diffraction grating according to the embodiment of the present invention was directly mounted on the spectroscopic analysis apparatus shown in FIG. 1, even if the replica was made using the diffraction grating according to the present invention as a base material, its optical characteristics did not change, It goes without saying that the same effect as in the above embodiment can be obtained even if a replica using the diffraction grating according to the present invention as a base material is mounted on the spectroscopic analyzer.

Including the above examples, the ratio of the intensity of the diffracted light to the abnormal peak with respect to the ratio P / S of the pitch dimension (P) of the diffraction grating to be exposed and the repeated exposure period (S) of small-angle deflection was determined. The result as shown in FIG. 15 was obtained. As the ratio P / S between the pitch dimension (P) of the diffraction grating to be exposed and the repeated exposure period (S) of small-angle deflection increases, the intensity of the abnormal peak decreases, but the intensity of the abnormal light is originally analyzed. In order to suppress the intensity of diffracted light used in the above to 10 ⁻⁵ or less, P / S needs to be 0.1 or more.

  According to the present invention, it is possible to control the appearance wavelength of abnormal light by adjusting the value of the pitch dimension S for repeated exposure in the equation (1). That is, the diffraction grating of the present invention and the spectroscopic analysis apparatus using the diffraction grating of the present invention can produce an electron beam having a pitch dimension of repeated exposure in the production of a diffraction grating by repeated exposure by an electron beam exposure apparatus applying a microfabrication technique for semiconductor elements. By setting the deflection region to an appropriate value, it is possible to manufacture a diffraction grating that suppresses the influence on the analysis accuracy of the extraordinary light by shifting the wavelength of the extraordinary light to a wavelength far from the original diffraction light wavelength.

  In addition, by setting the deflection region of the electron beam to an appropriate value in advance from the pitch size of the diffraction grating necessary for the analysis in manufacturing the diffraction grating, it is possible to manufacture the optimum diffraction grating for a desired spectroscopic analyzer.

  DESCRIPTION OF SYMBOLS 1 ... Light source, 2, 4 ... Slit, 3 ... Diffraction grating, 5, 7, 8 ... Mirror, 6 ... Half mirror, 9 ... Reference cell, 10 ... Sample cell, 11, 12 ... Lens, 13, 14 ... Detector 15 ... light, 16 ... diffracted light, 17 ... silicon substrate, 18 ... resist, 19 ... metal film, 20 ... electron gun, 21 ... electron beam, 22 ... first mask, 23,25 ... transfer lens, 24 ... variable Molding deflector, 26 ... aperture, 27 ... second mask, 28, 29 ... reduction lens, 30 ... small angle deflector, 31 ... large angle deflector, 32, 33 ... objective lens, 34 ... substrate, 35 ... stage, 36 ... Pattern dimension control system, 37 ... small angle deflection control system, 38 ... large angle deflection control system, 39 ... stage movement control system, 40, 45, 48 ... small angle deflection area, 41, 46, 49 ... adjacent small angle deflection area, 42, 47 , 50, 53, 56 ... diffraction grating line N and space pattern, 43, 51... First exposure small angle deflection area, 44, 52... Exposure second small angle deflection area, 100... Diffracted light, 101.

Claims (11)

In a method of producing a constant pitch diffraction grating by repeated exposure,
A method for producing a diffraction grating, characterized in that a repeated exposure is performed by setting a ratio P / S between a pitch dimension P of the diffraction grating and a pitch dimension S of a repeated exposure repeated area to be 0.1 or more. In the manufacturing method of the diffraction grating of Claim 1,
A method for manufacturing a diffraction grating, wherein the pitch dimension of the diffraction grating is 1 μm or less and the pitch dimension of the repeating region is 10 μm or less. In a method of producing a constant pitch diffraction grating by repeated exposure,
The ratio P / S of the pitch dimension P of the diffraction grating and the pitch dimension S of the repeated exposure repeated area is set to be 0.1 or more, and multiple exposures with different repeated exposure boundary positions are used in combination. A method for producing a diffraction grating, wherein repeated exposure is performed. In a method of producing a constant pitch diffraction grating used for spectroscopic analysis by repeated exposure,
Repeat exposure is performed by setting the repeat pitch dimension of the repeat area so that the absolute value of the difference between the spectral peak wavelength and the spectroscopic analysis wavelength resulting from the repeat pitch dimension of the repeat area is 1/10 or more of the spectroscopic analysis wavelength. A method for manufacturing a diffraction grating. In the manufacturing method of the diffraction grating as described in any one of Claim 1 to 4,
A method for producing a diffraction grating, wherein the repeated exposure is performed by an electron beam exposure method. In a method of repeatedly producing a diffraction grating with a constant pitch by line and space pattern unit,
Repeated small-angle deflection by setting the ratio P / S between the pitch P of the diffraction grating to be exposed and the small-angle deflection repetition exposure period S of the electron beam forming the line and space pattern to be 0.1 or more. A method for manufacturing a diffraction grating, wherein electron beam exposure is performed. In the manufacturing method of the diffraction grating according to claim 6,
A method for producing a diffraction grating, wherein the line-and-space pattern serving as an exposure unit has a length in the grating linear direction of the diffraction grating larger than a length in a direction perpendicular to the grating straight line of the diffraction grating . In a constant pitch diffraction grating produced by repeated exposure,
A diffraction grating, wherein the ratio P / S of the pitch dimension P of the diffraction grating and the pitch dimension S of the repeating region is 0.1 or more. The diffraction grating according to claim 8, wherein
A diffraction grating in which the pitch dimension of the diffraction grating is 1 μm or less and the pitch dimension of the repeating region is 10 μm or less. In a spectroscopic analyzer that analyzes the components of a sample from its transmission characteristics by irradiating the sample with light from a light source and then diffracting it with a diffraction grating.
As the diffraction grating, a diffraction grating having a constant pitch produced by repeated exposure and having a ratio P / S of the pitch dimension P of the diffraction grating to the pitch dimension S of the repeating region of 0.1 or more was used. A spectroscopic analyzer characterized by. The spectroscopic analyzer according to claim 10.
A spectroscopic analyzer using a diffraction grating having a pitch dimension of 1 μm or less and a pitch dimension of the repeating region of 10 μm or less.

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