JPS60106130A - Charged-beam exposure device - Google Patents

Abstract

PURPOSE:To form a charged-beam exposure device enabling a drawing of higher speed in an exposure device of a multibeam system using matrix blanks. CONSTITUTION:Beams passing through matrix blanks 22 are removed of unnecessary beams such as scattered beams by stops 23 and than enter a deflector 24. The deflector 24 comprises four X-Y deflectors arranged in 2X2 and subjects a plurality of matrix blanks separately to deflective control so that four images of matrix blanks A-D shown in the figure (a) may be arranged in the same sequence with those of disposed matrix blanks and at fixed intervals. The images thus obtained are reduced by a reducing lens 25. A reduced image is focused on a sample surface 29 by an objective lens 27.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a multi-beam charged beam exposure apparatus using an electron beam or an ion beam, which is used for forming fine patterns on semiconductor integrated circuits and the like.

[Background of the invention]

BACKGROUND ART Conventionally, various types of exposure apparatuses using a charged beam have been developed, including a spot beam using a single beam, a fixed shaped beam, and a variable shaped beam. However, since these methods use a single beam, high-density batts are required.1 For Si pattern writing, problems arise in that the writing time is long and the throughput is low. A multi-beam system that simultaneously generates multiple beams is promising for improving throughput. Multi-beam systems include those that control deflection, blacking, etc. of each beam in the same way, and those that control each beam independently. In the former case, only one deflector, blanker, etc. is required, but in the latter case, a control means such as a deflector, blanker, etc. is required for each beam. The former method has a problem with positioning accuracy because it is difficult to control each beam independently, but the latter method does not have this problem because each beam is controlled independently in principle. In the latter method, as the number of beams increases, the number of control means such as deflectors and blankers increases proportionally, so a control mechanism incorporating a large number of minute deflectors and blankers is required. A charged beam exposure apparatus using a matrix blanker incorporating a large number of blankers is described in detail in Japanese Patent Application No. 58-63772. Figure 1 shows a conceptual diagram of a matrix blanker. 11 is a slit having a plurality of openings, and 12 is a pair of electrodes having a deflection or blanker function corresponding to each opening. The charged beam passing through the aperture is deflected or beam-on by applying a voltage to the electrode 12.
It is controlled by circuit 1 which performs an off blanking operation. By the way, if we consider the case where the image of this aperture is reduced by an electron optical system and applied to fine batten drawing, the size of the aperture will be very small, several hundred μm or less, and the dimensions of the electrode 12 will also be similar. It becomes minute. A mesh of a certain width is formed between the openings of the slits 11, but this image is small compared to the size of the image of the openings, so that it can be ignored without affecting the intensity distribution of the beam. It is necessary to make the space between the openings sufficiently small. Since the size of the matrix blanker 10 is minute, a problem arises in that if the opening and the opening portion are further made smaller, it becomes difficult to manufacture the matrix blanker. In order to avoid this, the distance between the apertures is set to an integral multiple of the aperture size, and in this case, the part of the sample surface that is not irradiated with the beam, corresponding to the part between the apertures, must be exposed. Alternatively, a method can be considered in which the entire beam passing through the matrix blanker is softened by the distance between the apertures using a deflector, and this portion is exposed several times. However, this method has a problem in that since the exposure is divided into several times due to the deflection, the drawing time becomes longer due to dead time caused by the settling time of the deflector ODA converter.

[Purpose of the invention]

An object of the present invention is to provide a multi-beam type exposure apparatus using a matrix blanker, which enables higher-speed drawing.

[Summary of the invention]

The present invention is characterized in that, in order to achieve the above object, a plurality of matrix blankers each having an IJ socket-shaped aperture and an electrode for each aperture that deflects or blanks a charged beam passing through the aperture are provided. The aperture images on the sample surface formed by the apertures of each of the plurality of matrix blankers, which are arranged at regular intervals from each other, are
The present invention is characterized in that a deflector is provided for separately controlling the deflection of the plurality of matrix blankers so that they are arranged at regular intervals in the same order as the arrangement order of the IJ soxplan forces.

[Embodiments of the invention]

Examples of the charged beam exposure apparatus of the present invention will be shown below.
Its configuration and operation will be explained in detail.

The configuration of the charged beam exposure apparatus of the present invention is shown in FIG.

Here, 21 is a light source, 22 is a matrix blanker, 2
6 is an aperture, 24 is a deflector, 25 is a reduction lens, 26 is a blanking diaphragm, 27 is an objective lens, 28 is a positioning deflector, and 29 is a sample surface.

First, the matrix blanker 22 will be explained.

The explanatory diagram of the matrix blanker is shown in Fig. 6 and the plan view (a
), the elevation view is shown as (b). FIG. 6(a) is a diagram showing the correspondence between the opening arrangement of the slits of the matrix blanker and the arrangement of the matrix blanker. Here, 61
is a slit opening, and 62 is a 2×2 opening array corresponding to one matrix blanker. A, B, C, D
shall refer to the matrix blanker installed at the bottom of the slit corresponding to the open 1'' arrangement 62, respectively. Here, we show the case where the slit is formed by one plate. 2 corresponding to one matrix blanker
×2 aperture array 62 has an interval 21 twice the aperture size e.
They are arranged in a 2×2 pattern with . On the other hand, matrix blankers A, B, C, and D are arranged at intervals of 2×
It is arranged in 2. Although an example in which the matrix blankers are arranged at equal intervals is shown here, they may not be arranged at equal intervals.

The slits are made of one plate, but each matrix blanker may have an independent female structure, and does not need to be an integral structure. FIG. 6(b) is a diagram showing a matrix blanker. Here, 66 is a slit, 64 is an opening, 65 is one matrix blanker portion, and filter 6 is a blanker electrode. The slits 66 have openings arranged as shown in FIG. 6(a). Here, an example of a monolithic slit is shown. The beam passing through the opening 64 of the slit 36 is
It is turned on and off by blanker electrode 66. The beam turned off by the matrix blanker is cut by the blanking aperture shown in FIG. 26. Here, the blanking diaphragm is installed on the imaging plane of the reduction lens. Note that the blanking aperture may be installed anywhere as long as blanking is possible. The slit in Figure 6(a) is the second
As shown in the figure, it is uniformly illuminated by a light source 21. The beam that has passed through the matrix blanker is filtered by an aperture 26 to remove unnecessary beams such as scattered beams, and then enters a deflector 24 . The deflector 24 consists of four XY deflectors arranged in a 2×2 pattern. This deflector 24 is used to individually control the deflection of the four images of matrix blankers A, B, C, and D shown in FIG. 6(a), as will be explained later. Figure 4 shows how to create images of matrix blankers A, B, and C1D. Here, a, b, c, and d are matrix blankers A shown in FIG. 6(a), respectively.
, B, C, I) represent images corresponding to the slit openings. As shown in FIG. 4, a drawing area is formed by shifting the images of each matrix blanker in the X and Y directions by the distance between the openings so that the images of the openings of each matrix blanker do not overlap with each other. In this way, it is possible to irradiate everything within the square area with the beam at once.

FIG. 5 shows the method of pattern generation. Here, 51 is a drawable area, and 52 is a drawing pattern. The broken lines represent the division of the drawing button into aperture units. 52
When drawing a pattern, turn on the beam that passes through the aperture corresponding to the area divided by the dashed line, turn off the other areas, or turn off the beam that passes through the aperture corresponding to the area divided by the dashed line. , a matrix blanker is operated to turn on areas other than this to generate a drawing pattern. The image thus obtained is further reduced by a reduction lens 25. The reduced image is focused on a sample surface 29 by an objective lens 27. By operating the matrix blanker as described above, a desired pattern can be exposed onto the sample. When drawing a pattern exceeding the drawable area 51 shown in FIG. 5, the entire beam may be deflected to a desired position by the positioning deflector 28. Therefore, in order to expose the drawable area 51, it is only necessary to perform one deflection operation to align the beam position with the drawable area 51. This makes it possible to reduce dead time associated with deflection. In this way, the entire surface of the sample can be exposed by moving the sample stage in combination with this deflection operation. Note that here, the interval between the openings of the matrix blanker is assumed to be the same as the size of the openings, but this interval may be an integral multiple of the size of the openings, and it is not necessary to arrange them at the same interval in the XY directions.

For example, if the interval between the openings is set to 6 times the size of the openings,
In order to form a square drawing area by overlapping the images of the matrix blankers, the matrix blankers 2 may be arranged in a 6×3 arrangement. Note that the above-mentioned interval does not need to be an exact integral multiple of the size of the opening, and may be an integral multiple with some margin.

Next, other embodiments of the present invention will be described. In the embodiment described in No. 111j, only one light source illuminates the slit, but the beam current on the sample surface decreases accordingly because the slit is cut off at a portion other than the opening of the slit. In order to increase the beam current, use multiple light sources. FIG. 6 shows the configuration of a charged beam exposure apparatus when a plurality of light sources are provided. 61 is a light source, 62 is a matrix blanker, 6 is a diaphragm, 64 is a deflector, 65 is a reduction lens, 66 is a blanking diaphragm, 67 is an objective lens, 68 is a positioning deflector, and 69 is a sample surface. Here, as in the previous example, a 2×2 matrix blanker arrangement is used,
Slits having four sets of 2×2 aperture arrays are installed so that each set of aperture arrays corresponds to one matrix blanker. One light source is provided corresponding to each matrix blanker, and each light source arranged in a 2×2 array uniformly illuminates each matrix blanker arranged in a 2×2 array. The other parts have exactly the same configuration as in FIG. 2, and the drawing operation is performed in the same way. That is, as in FIG. 4, images of the matrix blanker are superimposed to form a rectangular drawing area, and a drawing pattern can be generated as shown in FIG. Although one light source is associated with each matrix blanker here, a plurality of light sources may be associated with each matrix blanker.

〔Effect of the invention〕

According to the present invention, a plurality of matrix blankers are illuminated with one or more light sources, and the beams from each matrix blanker are separately deflected by respective deflectors, so that an image of each of the plurality of matrix blankers is obtained. The aperture images created by adjacent matrix blankers are arranged adjacent to each other alternately on the sample surface at regular intervals, so a single operation of the matrix blanker can simultaneously draw complex patterns within a rectangular area on the sample surface. Therefore, the deflection operation can be reduced, and the influence of dead time due to the settling time of the deflector ODA converter can be reduced, which has the great effect of enabling high-speed drawing, and reducing the exposure of LSI's baton drawing. It is suitable for use as a device.

In addition, in the case of item 2, by using multiple light sources,
Compared to the case where one light source is used, there is an advantage that the beam current at the sample surface can be made thicker.

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram of a matrix blanker, Fig. 2 is a diagram showing the configuration of a charged beam exposure apparatus of the present invention, Fig. 6 is an explanatory diagram of the matrix blanker, (a) is a plan view, (1))
4 is a diagram showing a method of overlapping images of matrix blanker groups, FIG. 5 is a method of generating a bang, and FIG. 6 is a diagram showing the configuration of another charged beam exposure apparatus according to the present invention. be. Explanation of symbols 11.63...Slit 12...Electrode 13...
Blanking circuit 21.61...Light source 22.65.6
2...Matrix blanker 2 filter...Aperture 24.
64...Deflector 25.65...Reducing lens 26.66...Blanking aperture 27.67...Objective lens 28.68...Positioning deflector 29.69...Sample surface 61.34 ...Aperture 62...
-Aperture arrangement 66...Blanker electrode 51...Drawable area 52...Drawing Nokutan Patent Applicant Nippon Telegraph and Telephone Public Corporation Patent Attorney Junnosuke Nakatoshi 1 Figures 3 and 2 Figure 4p3 (Q) 1P4 Diagram P5

Claims (1)

[Claims] (1) A plurality of matrix blankers each having a two-dimensional matrix of apertures and an electrode for each aperture that deflects or blanks a charged beam passing through the apertures are arranged at a constant distance from each other. a deflector that separately deflects and controls each of the plurality of matrix blankers so that the open images on the sample surface formed by the respective openings of the matrix blankers are arranged at regular intervals in the same order as the arrangement order of the matrix blankers; A charged beam exposure device characterized in that: (2. A charged beam exposure apparatus according to claim 1, wherein each of the plurality of matrix blankers is a matrix blanker each having at least one light source.