JP6823823B2 - Charged particle beam drawing device, its control method and correction drawing data creation method - Google Patents

Description

The present invention relates to a charged particle drawing device for forming a pattern on the surface of an irradiated object by using a charged particle beam in an exposure stage, a control method thereof, and a correction drawing data creation method.

Multi-beam lithography using multi-beam has been developed conventionally. Multi-beam lithography is used to form a pattern on an irradiated object such as a silicon wafer.

In order to realize multi-beam lithography, an electron beam drawing apparatus using multi-beam is used. This electron beam drawing device includes an electron beam generator that generates an electron beam, an aperture device that generates a multi-beam containing a plurality of minute beams from the electron beam, and a deflection device that deflects the multi-beam and irradiates the irradiated object. A blanking device is provided between the aperture device and the deflection device.

Of these, the blanking device emits a desired microbeam to the outside among the multi-beams generated by the aperture device and guides the other microbeams to the deflecting device. This blanking device causes the multi-beam blanking. The ranking density (microbeam on / off density) can be changed from 0% to 100%. The beam emitted to the outside is absorbed by an absorption plate provided below the blanking device.

By the way, as a result of intensive research, the inventor of the present application distorts the minute beam passing through the absorption plate due to the Coulomb force generated between each minute beam and the fluctuation of the electromagnetic field caused by the minute beam absorbed by the absorption plate. I found that it would end up. Here, since the irradiation amount of the minute beam to the irradiated object fluctuates according to the drawing pattern on the irradiated object, the Coulomb force generated between the minute beams and the electromagnetic field caused by the absorption plate also fluctuate each time. .. Therefore, the distortion of the minute beam changes every time the blanking density of the multi-beam changes during the irradiation process of the charged particle beam, and this also causes the distortion of the minute beam to be in the proper position with respect to the irradiated object and to have the proper dose amount. It is newly found that it may not be possible to irradiate the multi-beam.

However, conventionally, a technique has been developed to solve the problem that the minute beam of the multi-beam is distorted due to the change of the blanking density of the multi-beam during the drawing of the electron beam writing apparatus, and the drawing pattern on the irradiated object is distorted due to this. Absent.

JP-A-2010-123966

The present invention has been made in consideration of such a point, and is a charged particle beam drawing apparatus capable of solving the problem that the drawing pattern is distorted due to a change in the blanking density of the multi-beam during drawing, and a control method thereof. An object of the present invention is to provide a method for creating correction drawing data.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. A deflector including an electron lens that deflects the multi-beam and irradiates the irradiated body, and an intervening between the aperture device and the deflector, removes a predetermined microbeam outward, and another microbeam. The control device includes a blanking device that guides the particles to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device that controls the blanking device, and the control device has a polygon having a plurality of vertices. The pattern area density map is obtained from the included drawing data, and the movement amount of each vertex is calculated for each vertex of the drawing data based on the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex. This is a charged particle beam drawing device characterized in that each side of drawing data is moved by the amount of movement of a vertex to create corrected drawing data, and drawing is performed based on the corrected drawing data.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. A deflecting device including an electronic lens that deflects the multi-beam and irradiates the irradiated body, and an intervening between the aperture device and the deflecting device, a predetermined minute beam is removed outward, and another minute beam is removed. The control device includes a blanking device that guides the particles to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device that controls the blanking device, and the control device has a polygon having a plurality of vertices. A pattern area density map is obtained from the included drawing data, and the movement amount of each side of the drawing data is calculated based on the relationship between the pattern area density map obtained in advance and the positional deviation of each side, and the drawing data is drawn. It is a charged particle beam drawing apparatus characterized in that correction drawing data is created by moving each side of the above by the amount of movement and drawing is performed based on the correction drawing data.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. A deflector including an electron lens that deflects the multi-beam and irradiates the irradiated body, and is interposed between the aperture device and the deflector to remove a predetermined microbeam outward and another microbeam. The control device includes a blanking device for guiding the deflection device to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device for controlling the blanking device, and the control device has a polygon having a plurality of vertices. The pattern area density map is obtained from the included drawing data, the amount of movement of the polygon in the drawing data is calculated based on the relationship between the pattern area density map obtained in advance and the positional deviation of the polygon, and the polygon of the drawing data is calculated. It is a charged particle beam drawing apparatus characterized in that a correction drawing data is created by moving the polygon with a moving amount of a polygon and drawing is performed based on the correction drawing data.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. A deflector including an electron lens that deflects the multi-beam and irradiates the irradiated body, and an intervening between the aperture device and the deflector, removes a predetermined microbeam outward, and another microbeam. The control device includes a blanking device that guides the particles to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device that controls the blanking device, and the control device has a polygon having a plurality of vertices. A pattern area density map is obtained from the included drawing data, a correction coefficient is obtained based on the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex, and each vertex of the drawing data is multiplied by the correction coefficient. A charged particle beam drawing device characterized in that the movement amount of each vertex is calculated, each side of the drawing data is moved by the movement amount of the vertex to create correction drawing data, and drawing is performed based on the correction drawing data. is there.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. A deflecting device including an electronic lens that deflects the multi-beam and irradiates the irradiated body, and is interposed between the aperture device and the deflecting device to remove a predetermined minute beam outward and another minute beam. The control device includes a blanking device that guides the particles to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device that controls the blanking device, and the control device has a polygon having a plurality of vertices. A pattern area density map is obtained from the included drawing data, and based on the relationship between the pattern area density map and the position shift map obtained in advance, each vertex of the drawing data is moved using the position shift map. It is a charged particle beam drawing apparatus characterized in that the amount is calculated, each side of the drawing data is moved by the movement amount of the vertices to create correction drawing data, and drawing is performed based on the correction drawing data.

The charged particle beam drawing according to any one of claims 1 to 5, wherein the pattern area density map divides a drawing field into a plurality of regions, and each region has an assigned pattern area density. It is a device. The present invention is a charged particle beam drawing apparatus, characterized in that the electron lens includes an electrostatic deflector having multiple poles.

The present invention is a charged particle beam drawing apparatus characterized in that the number of vertices of the polygon of the drawing data and the polygon of the correction drawing data are the same.

The present invention is a charged particle beam drawing apparatus characterized in that each side of the corrected drawing data is inclined with respect to the corresponding side of the drawing data in the XY directions.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. It is interposed between the deflection device including the electron lens that deflects the multi-beam and irradiates the irradiated body with the aperture device and the deflection device, removes a predetermined minute beam outward, and removes another minute beam. In a control method of a charged particle beam drawing device including a blanking device leading to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device for controlling the blanking device, a plurality of apexes. The drawing is based on the relationship between the step of acquiring the reference drawing data including the polygon having the above, the step of obtaining the pattern area density map from the drawing data, and the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex. A process of calculating the movement amount of each vertex for each vertex of data and moving each side of the drawing data by the movement amount of the vertex to create correction drawing data, and a process of drawing based on this correction drawing data. It is a control method of a charged particle beam drawing apparatus, which is characterized by having.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. It is interposed between the deflection device including the electron lens that deflects the multi-beam and irradiates the irradiated body with the aperture device and the deflection device, removes a predetermined minute beam outward, and removes another minute beam. In a control method of a charged particle beam drawing device including a blanking device leading to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device for controlling the blanking device, a plurality of apexes. The drawing is based on the relationship between the step of acquiring the reference drawing data including the polygon having the above, the step of obtaining the pattern area density map from the drawing data, and the relationship between the pattern area density map obtained in advance and the positional deviation of each side. For each side of the data, a step of calculating the movement amount and moving each side of the drawing data by the movement amount to create correction drawing data, and a step of drawing based on the correction drawing data are provided. This is a control method for a charged particle beam drawing device.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. It is interposed between the deflection device including the electron lens that deflects the multi-beam and irradiates the irradiated body with the aperture device and the deflection device, removes a predetermined minute beam outward, and removes another minute beam. In a control method of a charged particle beam drawing device including a blanking device leading to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device for controlling the blanking device, a plurality of apexes. The drawing is based on the relationship between the step of acquiring the reference drawing data including the polygon having the above, the step of obtaining the pattern area density map from the drawing data, and the relationship between the pattern area density map obtained in advance and the positional deviation of the polygon. It is characterized by having a process of calculating the movement amount of the polygon of data and moving the polygon of the drawing data by the movement amount to create correction drawing data, and a process of drawing based on the correction drawing data. This is a control method for a charged particle beam drawing device.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. It is interposed between the deflection device including the electron lens that deflects the multi-beam and irradiates the irradiated body with the aperture device and the deflection device, removes a predetermined minute beam outward, and removes another minute beam. In a control method of a charged particle beam drawing device including a blanking device leading to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device for controlling the blanking device, a plurality of apexes. The correction coefficient is based on the relationship between the process of acquiring the reference drawing data including the polygon having the above, the process of obtaining the pattern area density map from the drawing data, and the relationship between the previously obtained pattern area density map and the positional deviation of the polygon. And a step of multiplying each vertex of the drawing data by the correction coefficient to calculate the momentum of the vertex, and moving each side of the drawing data by the movement amount of the vertex to create the correction drawing data. A method for controlling a charged particle beam drawing device, which comprises the blanking device and a step of controlling the electronic lens based on the corrected drawing data.

The present invention includes a charged particle beam generator that generates a charged particle beam, an aperture device that passes the charged particle beam to generate a multi-beam including a plurality of minute beams, and includes an aperture having a plurality of openings. It is interposed between the deflection device including the electron lens that deflects the multi-beam and irradiates the irradiated body with the aperture device and the deflection device, removes a predetermined minute beam outward, and removes another minute beam. In a control method of a charged particle beam drawing device including a blanking device leading to the deflection device, an electron beam generator, an aperture device, the deflection device, and a control device for controlling the blanking device, a plurality of apexes. Based on the relationship between the step of acquiring the reference drawing data including the polygon having the above, the step of obtaining the pattern area density map from the drawing data, and the previously obtained pattern area density map and the misalignment map, the drawing data For each vertex, the movement amount of each vertex is calculated using the misalignment map, and each side of the drawing data is moved by the movement amount of the vertex to create the correction drawing data, and the correction drawing data It is a control method of a charged particle beam drawing apparatus, which comprises a step of drawing based on.

The present invention is characterized in that the pattern area density map divides the drawing data into a plurality of drawing fields, further divides each drawing field into a plurality of areas, and each area has an assigned pattern area density. It is a control method of a charged particle beam drawing device.

The present invention is a method for controlling a charged particle beam drawing apparatus, wherein the electron lens includes an electrostatic deflector having multiple poles.

The present invention is a control method for a charged particle beam drawing apparatus, characterized in that the number of vertices of the polygon of the drawing data and the polygon of the correction drawing data are the same.

The present invention is a control method for a charged particle beam drawing apparatus, characterized in that each side of the corrected drawing data is inclined with respect to the corresponding side of the drawing data in the XY directions.

The present invention is a method of creating correction data in a charged particle beam drawing apparatus, in which a step of acquiring drawing data including a polygon having a plurality of vertices and a step of obtaining a pattern area density map from the drawing data are obtained in advance. Based on the relationship between the pattern area density map and the positional deviation of each vertex, the amount of movement of the vertex is calculated for each vertex of the drawing data, and each side of the drawing data is moved by the amount of movement of the vertex to correct it. It is a correction drawing data creation method characterized by including a step of creating drawing data.

The present invention is a method of creating correction data in a charged particle beam drawing apparatus, in which a step of acquiring drawing data including a polygon having a plurality of vertices and a step of obtaining a pattern area density map from the drawing data are obtained in advance. Based on the relationship between the pattern area density map and the positional deviation of each side, the movement amount of each side of the drawing data is calculated, and each side of the drawing data is moved by the movement amount to obtain the corrected drawing data. It is a correction drawing data creation method characterized by having a step of creating it.

The present invention is a method of creating correction data in a charged particle beam drawing apparatus, in which a step of acquiring drawing data including a polygon having a plurality of vertices and a step of obtaining a pattern area density map from the drawing data are obtained in advance. A process of calculating the movement amount of the polygon of the drawing data based on the relationship between the pattern area density map and the positional deviation of the polygon, and moving the polygon of the drawing data by the movement amount to create correction drawing data. It is a correction drawing data creation method characterized by having.

The present invention is a method of creating correction data in a charged particle beam drawing apparatus, in which a step of acquiring drawing data including a polygon having a plurality of vertices and a step of obtaining a pattern area density map from the drawing data are obtained in advance. The process of obtaining the correction coefficient based on the relationship between the pattern area density map and the positional deviation of each vertex, and the calculation of the movement amount of the vertex by multiplying each vertex of the drawing data by the correction coefficient, and drawing data. This is a correction drawing data creation method characterized by comprising a step of moving each side of the above by the amount of movement of the vertices to create correction drawing data.

The present invention is a method of creating correction data in a charged particle beam drawing apparatus, in which a step of acquiring drawing data including a polygon having a plurality of vertices and a step of obtaining a pattern area density map from the drawing data are obtained in advance. The process of obtaining the correction coefficient based on the relationship between the pattern area density map and the positional deviation of each vertex, and the calculation of the movement amount of the vertex by multiplying each vertex of the drawing data by the correction coefficient, and drawing data. This is a correction drawing data creation method characterized by comprising a step of moving each side of the above by the amount of movement of the vertices to create correction drawing data.

The present invention is a method of creating correction data in a charged particle beam drawing apparatus, in which a step of acquiring drawing data including a polygon having a plurality of vertices and a step of obtaining a pattern area density map from the drawing data are obtained in advance. Based on the relationship between the pattern area density map and the misalignment map, the movement amount of each vertex is calculated for each vertex of the drawing data using the misalignment map, and each side of the drawing data is moved. This is a correction drawing data creation method characterized by comprising a step of moving by an amount to create correction drawing data.

The present invention is characterized in that the pattern area density map divides the drawing data into a plurality of drawing fields, further divides each drawing field into a plurality of areas, and each area has an assigned pattern area density. This is a correction drawing data creation method.

The present invention is a correction drawing data creation method characterized in that the pattern area density map divides a drawing field into a plurality of areas and each area has an assigned pattern area density.

As described above, according to the present invention, the pattern area density map is obtained from the drawing data including the polygon having a plurality of vertices, and the drawing data is corrected based on this pattern area density map. Therefore, a multi-beam is used. Therefore, the desired charged particle beam drawing can be realized.

FIG. 1 is a schematic view showing a charged particle beam drawing apparatus according to the present invention. FIG. 2 is a cross-sectional view showing an aperture device and a blanking device. FIG. 3 is a plan view showing an aperture device. FIG. 4 is a flowchart showing a control method of the charged particle beam drawing device. FIG. 5A is a diagram showing a pattern area density map of drawing data, and FIG. 5B is a diagram showing a blanking density. 6 (a) and 6 (b) are diagrams showing the amount of misalignment of the multi-beam. FIG. 7 is a diagram showing a position shift map of the reference drawing data. FIG. 8 is a diagram showing a linear correction function. 9 (a), (b), (c), (d), (e), and (f) are diagrams showing a method of creating correction drawing data. FIG. 10 is a diagram showing a pattern area density map and a list of pattern area density maps having correction coefficients corresponding thereto. FIG. 11A is a diagram showing drawing data before correction, and FIG. 11B is a diagram showing a state in which drawing data is divided into a plurality of drawing fields. FIG. 12 is a diagram showing reference drawing data. FIG. 13 is a diagram showing a modified example of the present invention. FIG. 14 is a diagram showing a modified example of the present invention. FIG. 15 is a diagram showing a modified example of the present invention. 16 (a), (b), (c), (d), (e), and (f) are views showing further modifications of the present invention. 17 (a) and 17 (b) are views showing further modifications of the present invention.

<Embodiment of the present invention>
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the charged particle beam drawing apparatus 1 according to the present invention is used to expose an irradiated object such as a silicon wafer to form a pattern, and includes an illumination system 2 and a PD (Pattern Definition). , Pattern determination) system 3, projection system 4, and substrate station 5 including a substrate stage 14 holding a substrate (illuminated body) 13. The entire charged particle beam drawing apparatus 1 is held in a high vacuum so that the beams 1a, 1b, and 1c propagate without being obstructed along the optical axis cx of the apparatus (shown in the figure). It is housed in the vacuum.

Among the charged particle beam drawing devices 1, the illumination system 2 includes an electron gun (charged particle beam generator) 7 that generates a charged particle beam 1a such as an electron beam, an extraction system 8, and a condenser lens system 9. Including. The charged particle beam drawing apparatus 1 may include a general blanking polarizing device 9a. However, as the charged particle beam, in general, other charged particles can be used as well instead of the electron beam. For example, in addition to electron beams, these may use, for example, hydrogen ions or heavy ions, charged atom clusters, or charged molecules, where "heavy ions" are ionic elements heavier than C, such as O, N, or Ne, Ar. , Kr, Xe and other rare gases.

The charged particle beam 1b emitted from the illumination system 2 by the condenser lens system 9 is a wide, substantially telecentric particle beam. The charged particle beam 1b then enters the PD system 3.

FIG. 2 describes the details of the cross section of the PD system 3 in more detail. This shows a beam 1b structured into a patterning beam, but for simplification, only two beams 20 are described instead of the plurality of beams. The deflected beam 21 is indicated by a dotted line wherever possible the beam is deflected off its path.

The PD system 3 of FIG. 2 includes an aperture device 30 including a continuously arranged aperture plate 16 and a blanking device 17A including a blanking plate 17.

The aperture plate 16 has an optional protective layer 15 that protects the plate from colliding energy particles and a plurality of openings 22 and 23 (see FIG. 3).

The blanking plate 17 also has several openings 17a corresponding to the openings 22 and 23 of the aperture plate 16. Each opening 17a comprises a set of blanking means acting on the beamlet beyond the region. In FIG. 2, these blanking means include a set of electrodes, namely a ground electrode 18 and a deflection electrode 19. By energizing these electrodes 18 and 19, the opening 17a can be "switched off", which deflects the beam (path indicated by the dotted arrow 21) and thus reaches the substrate 13. There is no such thing. When the electrodes are not energized, the opening 17a is "switched on" and the beam is not deflected from its path (arrow 20). Energization is performed by applying a voltage between electrodes 18 and 19 that is sufficiently different from the default voltage in the non-energized state, and the default voltage is usually zero, that is, the electrodes are at the same potential (energized). Within a small tolerance compared to the voltage). The energizing voltage is typically in the range of a few volts.

Then, the charged particle beam 1b that has passed through the PD system 3 becomes a multi-beam 1c including a plurality of minute beams by the aperture device 30 of the PD system 3, and the predetermined minute beams are removed outward by the blanking device 17A. The projection system 4 is irradiated with the multi-beam 1c containing only other minute beams. Here, by being turned on / off (ON / OFF) by the blanking device 17A, the multi-beam 1c has a desired blanking density. The blanking density of this multi-beam will be described later.

In the embodiment shown in FIG. 1, the projection system 4 is composed of a plurality of continuous particle-optical projection device stages consisting of an electrostatic or electronic lens, or other deflecting means. These lenses and means are shown only in symbolic form because their applications are well known from the prior art. The projection system 4 forms a reduced image by the crossovers c1 and c2. The reduction ratio for both stages is selected so that the overall reduction is in the hundreds, eg 200x (FIG. 1 is not scaled).

Measures are taken throughout the projection system 4 to extensively compensate the lens and / or deflection means for color and geometric aberrations. As a means for shifting the image as a whole in the lateral direction, that is, along the direction perpendicular to the optic axis cx, the projection system 4 has both the first deflection means 11 and the second deflection means 12 made of an electronic lens. including. The first deflection means 11 and the second deflection means 12 are, for example, near the crossover in the first deflection means 11 as shown in FIG. 1, or as in the case of the second stage deflection means 12 shown in FIG. It can be realized as a multi-pole electrode system arranged either after the final lens of the projection device. In this device, the multi-pole electrodes shift the image in relation to the movement of the steps. Further, it is used as a deflection means for two purposes of correcting the imaging system together with the alignment system. Further, the projection system 4 has an absorption plate 10 provided between the first deflection means 11 and the second deflection means 12.

Further, the projection system 4 is provided between the PD system 3 and the deflection means 11, between the first deflection means 11 and the absorption plate 10, and between the absorption plate 10 and the second polarization means 12, respectively. The condenser lens 6 is included. Further, the substrate stage 14 holding the substrate 13 can be moved in the left-right direction (horizontal direction) in FIG.

Each component constituting the charged particle beam drawing device 1, for example, an electron gun 7, a blanking device 17A, a first deflection means 11, a second deflection means 12, and a substrate stage 14 are all control devices 35. Is driven and controlled by.

By the way, drawing data 40A to be drawn on the substrate 13 is input to the control device 35, and the drawing data 40A is a pattern area including the pattern area density for each region of the multi-beam 1c irradiated on the substrate 13. Includes density map information.

Here, the relationship between the blanking density of the multi-beam and the pattern area density will be briefly described below. As shown in FIG. 5B, for example, the blanking density refers to the regions of the multi-beam 1c corresponding to the aperture plate 16 as four regions A1, A2, and A3 in the upper left, upper right, lower left, and lower right. , A4, the density of fine beams existing in each region A1, A2, A3, A4. The blanking density of such a multi-beam 1c is such that a predetermined minute beam is removed outward from the multi-beam 1c including a plurality of minute beams generated by the aperture device 30, and the other minute beams are removed from the illumination system 4. It can be generated by the blanking device 17A that leads to. On the other hand, the pattern area density refers to, for example, as shown in FIG. 5A, the region corresponding to the aperture plate 16 in the multi-beam 1c is the four regions A1, A2, upper left, upper right, lower left, and lower right. It refers to the density of patterns existing in each region A1, A2, A3, A4 when divided into A3 and A4. The pattern area density is the density of the region to be irradiated with the electron beam, and when the pattern area density changes, the blanking density changes accordingly. At this time, if the pattern area density changes, the drawing pattern may be distorted.

In FIG. 5A, the upper left region A1 and the upper right region A2 of the multi-beam 1c have a pattern area density of 100%, and most of the minute beams are guided to the illumination system 4.

On the other hand, the pattern area density of the lower left region A3 of the multi-beam 1c is 20%, a large number of minute beams are removed outward, and the pattern area density of the lower right region A4 is 60%. There is.

By the way, as a result of intensive research by the inventor of the present application, the multi-beam 1c including a plurality of minute beams has a Coulomb force generated between each minute beam and a fluctuation of an electromagnetic field caused by a minute beam absorbed by an absorption plate. It was discovered that the minute beam passing through the stopper plate was distorted due to this. The Coulomb force generated between each minute beam and the amount of the minute beam absorbed by the absorption plate change each time the blanking density of the multi-beam changes during the irradiation process of the charged particle beam, so it corresponds to the pattern area density. Therefore, the amount of distortion of each minute beam may change.

For example, as shown in FIG. 6A, when the minute beams 1d are arranged in the entire area of the multi-beam 1c without being chipped in a substantially grid pattern, that is, the pattern area density is 100% and the multi-beam 1c is arranged in the entire area. In this case, each minute beam 1d is arranged along a grid pattern in the first deflection means 11.

In FIG. 6A, the first deflection means 11 comprises an electronic lens 11A having eight poles 11a.

On the other hand, as shown in FIG. 6B, when the minute beam 1d is missing in the upper left region of the multi-beam 1c, the pattern area density is 0% in the upper left region, and the pattern area density is 100% in the other regions. It becomes.

In this case, an imbalance occurs in the forces such as the Coulomb force acting between the minute beams 1d in the electronic lens 11A having eight poles 11a. Therefore, for example, the minute beams 1d arranged from the upper side to the lower side in the center. The line L1 connecting the above is not a straight line but a distorted line.

In such a case, the drawing data 40A is corrected to obtain the corrected drawing data 40C as described later, and the corrected drawing data 40C is used instead of the drawing data 40A. As a result, the distortion of the multi-beam 1c can be interpolated, and the multi-beam with an appropriate dose amount can be irradiated to an appropriate position to generate a distortion-free drawing pattern.

Next, the operation of the present embodiment having such a configuration will be described.
As shown in FIG. 4, drawing data 40A including the drawing pattern before correction is input to the control device 35 (see FIG. 9A).

Next, as shown in FIGS. 11A and 11B, the control device 35 divides the input drawing data 40A into drawing data for each drawing field corresponding to the aperture plate 16. Here, FIG. 11A shows drawing data 40A input to the control unit 35, and FIG. 11B shows drawing data divided for each drawing field corresponding to the aperture plate 16. Next, the drawing data 40A divided for each drawing field is divided into, for example, four regions, the pattern area density of each region is obtained, and the pattern area density map including the pattern area density for each region is obtained.

On the other hand, as shown in FIG. 12, the control device 35 is obtained and input to the value of the positional deviation of the drawing pattern when drawing is performed using the pattern area density map which is a reference obtained in advance. Then, the control device 35 obtains a correction coefficient for correcting the positional deviation of each vertex based on the relationship between the pattern area density map input in advance and the positional deviation of the drawing pattern. The relationship between the pattern area density map as a reference and the correction coefficient is stored in the control device 35 in the form of a list (see FIG. 10).

FIG. 12 shows drawing data 50 including a reference drawing pattern shown on the drawing field corresponding to the aperture plate 16.

The reference drawing data 50 shown in FIG. 12 is divided into drawing fields in advance, and the reference drawing data is further divided into four business areas, and the upper left area and the lower right area are adjusted. The pattern 50b has a pattern area density of 60%. The lower left region has a pattern area density of 100% due to the adjustment pattern 50b, and the upper right region has no adjustment pattern and has a pattern area density of 0%.

Further, a cross pattern 50a for position measurement is provided in each of the upper left region, the lower left region, the upper right region, and the lower right region, and the value of the positional deviation of the drawing pattern can be obtained from the cross pattern 50a. it can. Then, as described above, a correction coefficient for correcting the positional deviation of each vertex can be obtained based on the relationship between the reference pattern area density map and the positional deviation of the drawing pattern.

As such a reference pattern area density map and a correction coefficient for correcting the positional deviation of each vertex of the drawing data, for example, a linear correction coefficient as shown in FIG. 8 can be considered. In FIG. 8, correction coefficients a, b, c, d, tx, and ty are used, where a, b, c, and d represent the components of enlargement / reduction, shear, and rotation, and tx and ty represent the components of translation.

Next, a method for specifically obtaining the linear correction coefficient will be described with reference to FIG. A drawing pattern is drawn using drawing data including a reference drawing pattern 50 including a cross pattern 50a as shown in FIG. 12 and an adjustment pattern 50b for adjusting the area density in a field size corresponding to the area of the aperture plate 16. Here, it is divided into four regions, an upper left portion, a lower left portion, an upper right portion, and a lower right portion, and the pattern area densities are 60%, 0%, 100%, and 60%, respectively. After that, the position of the cross pattern 50a is measured by the position measuring device to obtain a position shift map as shown in FIG. 7. The correction coefficients a, b, c, d, tx, and ty are obtained by calculating this amount of misalignment so as to approach the ideal grid by the method of least squares.

Next, the control device 35 selects the pattern area density corresponding to the drawing data 40A before correction and the correction coefficient. Next, the control unit 35 obtains each vertex of the polygon of the input drawing data 40A before correction. After that, the control device 35 multiplies each vertex of the polygon thus obtained by the above-mentioned correction coefficient to obtain the movement amount δ (delta) of each vertex. The movement amount δ when the above linear correction coefficient is used is calculated as δx = x−x ′ and δy = y−y ′. Here, x and y indicate the coordinates of each vertex, and x'and y'indicate the values obtained by multiplying the x and y coordinates by the correction coefficient as shown in FIG.

Next, each vertex of the polygon is moved by the movement amount δ, and each side of the drawing data is moved together with the vertex. In this way, the correction drawing data is obtained.

Next, with reference to FIGS. 9A to 9F, a method of creating correction drawing data obtained by moving each vertex of the drawing data 40A by a movement amount δ and moving each side accordingly will be described in detail. .. First, FIG. 9A shows drawing data 40A before correction including a polygon having eight vertices.

The arrows in FIG. 9A indicate the amount of misalignment of each vertex of the drawing data 40A calculated by using the correction coefficient obtained by the above method and the direction thereof. In order to correct this misalignment, each vertex of the drawing data 40A is moved by the movement amount δ obtained by the above method. That is, the vertex 1 of the drawing data is moved to the upper left in advance to obtain the intermediate drawing data 40B (FIG. 9B). Next, the vertex 2 of the intermediate drawing data 40B is moved (FIG. 9C), and the vertex 3 of the intermediate drawing data 40B is similarly moved. By sequentially moving the vertices 4, 5, 6, 7, and 8 of the intermediate drawing data 40B in this way, the corrected drawing data 40C is obtained (see FIGS. 9D, 9e, and 9F). Here, the number of polygon vertices of the drawing data 40A before correction is the same as the number of polygon vertices of the correction drawing data 40C after correction. Further, each side of the polygon of the correction drawing data 40c is inclined with respect to the corresponding side of the drawing data 40A before correction in the XY directions. In FIGS. 9A to 9F, the vertical direction is the X direction and the horizontal direction is the Y direction.

After that, the control device 35 executes an actual drawing operation using the corrected drawing data obtained by correcting each vertex of the reference drawing data. Specifically, a charged particle beam 1a is generated from the electron gun 7, and the charged particle beam 1a passes through the illumination system 2 to become a beam 1b and enters the PD system 3. Next, the beam 1b becomes a multi-beam 1c including a plurality of minute beams 1d by the aperture device 30 of the PD system 3, and the multi-beam 1c has a desired blanking density by the blanking device 17A.

After that, the multi-beam 1c enters the projection system 4 from the PD system 3 and is then irradiated onto the substrate 13 held on the substrate stage 14 of the substrate station 5.

During this time, the control device 35 controls the charged particle beam drawing device 1 using the correction drawing data 40C as described above. Therefore, it is possible to irradiate the multi-beam 1c with an appropriate dose amount at an appropriate position on the substrate 13.

As described above, according to the present embodiment, the control device 35 obtains the correction drawing data by multiplying the input reference drawing data of the polygon by the correction coefficient for each vertex. Next, the blanking device 17A, the first deflection means 11, and the second deflection means 12 can be controlled using the corrected drawing data. Therefore, it is possible to irradiate the multi-beam 1c with an appropriate dose amount at an appropriate position on the substrate 13. Further, the number of polygon vertices of the drawing data before correction and the number of polygon vertices of the drawing data after correction are the same. For example, in FIGS. 9A to 9F, the polygon of the drawing data 40A before correction has eight vertices, and the polygon of the drawing data 40C after correction has eight vertices. Therefore, it is not necessary to excessively increase the amount of the corrected drawing data, and appropriate control can be performed.

<Modified example of the present invention>
Next, FIGS. 13 to 15 will be described as a modification of the present invention. As shown in FIG. 14, drawing data 40A including the drawing pattern before correction is input to the control device 35 (see FIG. 9A).

Next, as shown in FIGS. 11A and 11B, the control device 35 divides the input drawing data 40A into drawing data 40A for each drawing field corresponding to the aperture plate 16. Here, FIG. 11A shows the drawing data 40A input to the control unit 35, and FIG. 11B shows the drawing data 40A divided for each drawing field corresponding to the aperture plate 16.

Next, the drawing data 40A divided for each drawing field is divided into, for example, four regions, the pattern area density of each region is obtained, and a map of the pattern area density including the pattern area density for each region is obtained.

On the other hand, as shown in FIG. 12, the control device 35 is obtained and input to the value of the positional deviation of the drawing pattern when drawing using the pattern area density map which is a reference obtained in advance. Then, the control device 35 obtains a position shift map that corrects the position shift of each vertex based on the relationship between the pattern area density map input in advance and the position shift of the drawing pattern. The relationship between the pattern area density map as a reference and the misalignment map is stored in the control device 35 in the form of a list (see FIG. 13).

Next, a method for specifically obtaining a misalignment map will be described. A drawing pattern is drawn using drawing data including a reference drawing pattern 50 including a cross pattern 50a as shown in FIG. 12 and an adjustment pattern 50b for adjusting the area density in a field size corresponding to the area of the aperture plate 16. Here, it is divided into four regions, an upper left portion, a lower left portion, an upper right portion, and a lower right portion, and the pattern area densities are 60%, 0%, 100%, and 60%, respectively. After that, the position of the cross pattern 50a is measured by a position measuring device to obtain a position shift map as shown in FIG. 7.

Next, the control device 35 selects the pattern area density corresponding to the drawing data 40A before correction and the misalignment map. Next, the control unit 35 obtains each vertex of the polygon of the input drawing data 40A before correction. After that, the control device 35 calculates the coordinates of each vertex of the polygon thus obtained, and obtains the amount of misalignment at those coordinates by bilinear interpolation as shown in FIG. 15 from the misalignment map obtained above. The amount of movement δ (delta) of each vertex is obtained by the opposite vector of the amount of misalignment obtained above.

Next, each vertex of the polygon is moved by the movement amount δ, and each side of the drawing data is moved together with the vertex. In this way, the correction drawing data is obtained.

Next, with reference to FIGS. 9A to 9F, the method of creating the correction drawing data obtained by moving each vertex of the reference drawing data 40A by the movement amount δ and moving each side accordingly is described in detail. To do.

First, FIG. 9A shows drawing data 40A before correction including a polygon having eight vertices.

The arrows in FIG. 9A indicate the amount of misalignment of each vertex of the drawing data 40A obtained by the above method and the direction thereof. In order to correct this misalignment, each vertex of the drawing data 40A is moved by the movement amount δ obtained by the above method. That is, the vertex 1 of the drawing data is moved to the upper left in advance to obtain the intermediate drawing data 40B (FIG. 9B). Next, the vertex 2 of the intermediate drawing data 40B is moved (FIG. 9C), and the vertex 3 of the intermediate drawing data 40B is similarly moved. By sequentially moving the vertices 4, 5, 6, 7, and 8 of the intermediate drawing data 40B in this way, the corrected drawing data 40C is obtained (see FIGS. 9D, 9e, and 9F). Here, the number of polygon vertices of the drawing data 40A before correction is the same as the number of polygon vertices of the correction drawing data 40C after correction. Further, each side of the polygon of the correction drawing data 40C is inclined with respect to the corresponding side of the drawing data 40A before correction in the XY directions.

Next, another modification of the present invention will be described. In the above-described embodiments and modifications, an example of obtaining corrected drawing data by moving the vertices of the polygon of the drawing data has been shown, but the above-mentioned movement is not limited to this, and the above-mentioned movement is performed for each side of the polygon of the drawing data. The amount may be obtained, and each side may be moved by this amount of movement to obtain the corrected drawing data 40C (see FIGS. 16 (a), (b), (c), (d), (e), and (f)). Further, the movement amount of the polygon of the drawing data may be obtained, and the correction drawing data 40C may be obtained by moving the polygon by this movement amount (see FIGS. 17A and 17B).

1 Charged particle beam drawing device 1a Beam 1b Beam 1c Multi-beam 1d Micro beam 2 Illumination system 3 PD system 4 Projection system 5 Substrate station 6 Condensing lens 7 Electron gun 9 Condensing lens system 10 Absorption plate 11 First deflection means 12 Second deflection means 13 Substrate 14 Substrate stage 16 Aperture plate 17 Branking plate 17A Branking device 17a Apertures 22, 23 Aperture 30 Aperture device 35 Control device 40A Drawing data 40B Intermediate drawing data 40C Correction drawing data 50 Reference drawing data 50a Cross pattern 50b Adjustment pattern

Claims (22)

A charged particle beam generator that generates a charged particle beam,
An aperture device that passes through the charged particle beam to generate a multi-beam containing a plurality of minute beams, and also includes an aperture having a plurality of apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body,
A blanking device that is interposed between the aperture device and the deflection device, removes a predetermined minute beam outward, and guides another minute beam to the deflection device.
The electron beam generator, the aperture device, the deflection device, and the control device for controlling the blanking device are provided.
The control device obtains a pattern area density map from drawing data including a polygon having a plurality of vertices, and based on the relationship between the previously obtained pattern area density map and the positional deviation of each vertex, each vertex of the drawing data. A charged particle beam characterized in that the movement amount of each vertex is calculated, each side of the drawing data is moved by the movement amount of the vertex to create correction drawing data, and drawing is performed based on the correction drawing data. Drawing device. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes through the charged particle beam to generate a multi-beam containing a plurality of minute beams, and also includes an aperture having a plurality of apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body, and is interposed between the aperture device and the deflection device to remove a predetermined minute beam to the outside and other minute beams. With a blanking device that guides the
The electron beam generator, the aperture device, the deflection device, and the control device for controlling the blanking device are provided.
The control device obtains a pattern area density map from drawing data including a polygon having a plurality of vertices, and based on the relationship between the pattern area density map obtained in advance and the positional deviation of each side, each side of the drawing data. A charged particle beam drawing device characterized in that it calculates the amount of movement of the drawing data, moves each side of the drawing data by the amount of movement to create correction drawing data, and draws based on the correction data. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes through the charged particle beam to generate a multi-beam containing a plurality of minute beams, and also includes an aperture having a plurality of apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body, and is interposed between the aperture device and the deflection device to remove a predetermined minute beam to the outside and other minute beams. With a blanking device that guides the
The electron beam generator, the aperture device, the deflection device, and the control device for controlling the blanking device are provided.
The control device obtains a pattern area density map from drawing data including a polygon having a plurality of vertices, obtains a correction coefficient based on the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex, and obtains the correction coefficient. for each vertex of the drawing data to calculate the amount of movement of each vertex by multiplying the correction coefficient, the respective sides of the drawing data to move in the movement amount of a vertex to create a corrected drawing data, based on the corrected drawing data A charged particle beam drawing device characterized by drawing. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes through the charged particle beam to generate a multi-beam containing a plurality of minute beams, and also includes an aperture having a plurality of apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body, and is interposed between the aperture device and the deflection device to remove a predetermined minute beam to the outside and other minute beams. With a blanking device that guides the
The electron beam generator, the aperture device, the deflection device, and the control device for controlling the blanking device are provided.
The control device obtains a pattern area density map from drawing data including a polygon having a plurality of vertices, and for each vertex of the drawing data based on the relationship between the pattern area density map and the misalignment map obtained in advance. The feature is that the movement amount of each vertex is calculated using the misalignment map, each side of the drawing data is moved by the movement amount of the vertex to create correction drawing data, and drawing is performed based on this correction drawing data. Charged particle beam drawing device. The charged particle beam drawing apparatus according to any one of claims 1 to 4 , wherein the pattern area density map divides a drawing field into a plurality of areas, and each area has an assigned pattern area density. The charged particle beam drawing apparatus according to any one of claims 1 to 5 , wherein the electron lens includes an electrostatic deflector having multiple poles. The charged particle beam drawing apparatus according to any one of claims 1 to 6 , wherein the number of vertices of the polygon of the drawing data and the polygon of the correction drawing data are the same. The charged particle beam according to any one of claims 1, 2, 3 to 7 , wherein each side of the corrected drawing data is inclined with respect to the corresponding side of the drawing data in the XY directions. Drawing device. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes a charged particle beam to generate a multi-beam containing multiple microbeams and includes an aperture with multiple apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body,
A blanking device that is interposed between the aperture device and the deflection device, removes a predetermined minute beam outward, and guides another minute beam to the deflection device.
In a control method of a charged particle beam drawing device including an electron beam generator, an aperture device, a deflection device, and a control device for controlling the blanking device.
The process of acquiring reference drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
Based on the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex, the movement amount of each vertex is calculated for each vertex of the drawing data, and each side of the drawing data is the movement amount of the vertex. The process of moving with to create correction drawing data,
A control method for a charged particle beam drawing apparatus, which comprises a step of drawing based on this corrected drawing data and a process of drawing. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes a charged particle beam to generate a multi-beam containing multiple microbeams and includes an aperture with multiple apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body,
A blanking device that is interposed between the aperture device and the deflection device, removes a predetermined minute beam outward, and guides another minute beam to the deflection device.
In a control method of a charged particle beam drawing device including an electron beam generator, an aperture device, a deflection device, and a control device for controlling the blanking device.
The process of acquiring reference drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
Based on the relationship between the pattern area density map obtained in advance and the positional deviation of each side, the movement amount is calculated for each side of the drawing data, and each side of the drawing data is moved by the movement amount. The process of creating correction drawing data and
A control method for a charged particle beam drawing apparatus, which comprises a step of drawing based on this corrected drawing data and a process of drawing. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes a charged particle beam to generate a multi-beam containing multiple microbeams and includes an aperture with multiple apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body,
A blanking device that is interposed between the aperture device and the deflection device, removes a predetermined minute beam outward, and guides another minute beam to the deflection device.
In a control method of a charged particle beam drawing device including an electron beam generator, an aperture device, a deflection device, and a control device for controlling the blanking device.
The process of acquiring reference drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
The process of obtaining the correction coefficient based on the relationship between the pattern area density map obtained in advance and the positional deviation of the polygon, and
For each vertex of the drawing data, the steps of said multiplying a correction factor to calculate the amount of movement of the vertices, to create the corrected drawing data each side of the drawing data to move in the movement amount of a vertex,
A control method for a charged particle beam drawing device, which comprises a blanking device and a step of controlling the electronic lens based on the corrected drawing data. A charged particle beam generator that generates a charged particle beam,
An aperture device that passes a charged particle beam to generate a multi-beam containing multiple microbeams and includes an aperture with multiple apertures.
A deflection device including an electronic lens that deflects the multi-beam and irradiates the irradiated body,
A blanking device that is interposed between the aperture device and the deflection device, removes a predetermined minute beam outward, and guides another minute beam to the deflection device.
In a control method of a charged particle beam drawing device including an electron beam generator, an aperture device, a deflection device, and a control device for controlling the blanking device.
The process of acquiring reference drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
Based on the relationship between the pattern area density map and the position shift map obtained in advance, the movement amount of each vertex is calculated for each vertex of the drawing data using the position shift map, and each side of the drawing data. And the process of creating correction drawing data by moving with the amount of movement of the vertices,
A control method for a charged particle beam drawing apparatus, which comprises a step of drawing based on this corrected drawing data and a process of drawing. The pattern area density map, the drawing data is divided for each of a plurality of drawing fields, according to claim 9, further each drawing field is divided into a plurality of areas, characterized by having a pattern area density, each region is assigned A method for controlling a charged particle beam drawing device according to any one of 12 to 12 . The method for controlling a charged particle beam drawing apparatus according to any one of claims 9 to 13, wherein the electron lens includes an electrostatic deflector having multiple poles. The control method for a charged particle beam drawing device according to any one of claims 9 to 14 , wherein the number of vertices of the polygon of the drawing data and the polygon of the correction drawing data are the same. The charged particle beam according to any one of claims 9, 10, 11 to 15 , wherein each side of the corrected drawing data is inclined with respect to the corresponding side of the drawing data in the XY directions. How to control the drawing device. In the correction data creation method in the charged particle beam drawing device,
The process of acquiring drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
Based on the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex, the amount of movement of the vertices is calculated for each vertex of the drawing data, and each side of the drawing data is calculated by the amount of movement of the vertex. A method for creating correction drawing data, which comprises a process of moving and creating correction drawing data. In the correction data creation method in the charged particle beam drawing device,
The process of acquiring drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
Based on the relationship between the pattern area density map obtained in advance and the positional deviation of each side, the movement amount is calculated for each side of the drawing data, and each side of the drawing data is moved by the movement amount. A method for creating corrected drawing data, which comprises a process of creating corrected drawing data. In the correction data creation method in the charged particle beam drawing device,
The process of acquiring drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
The process of obtaining the correction coefficient based on the relationship between the pattern area density map obtained in advance and the positional deviation of each vertex, and
Each vertex of the drawing data is multiplied by the correction coefficient to calculate the amount of movement of the apex, and each side of the drawing data is moved by the amount of movement of the apex to create correction drawing data. A method for creating corrected drawing data. In the correction data creation method in the charged particle beam drawing device,
The process of acquiring drawing data including polygons with multiple vertices,
The process of obtaining the pattern area density map from the drawing data and
Based on the relationship between the pattern area density map and the misalignment map obtained in advance,
For each vertex of the drawing data, the movement amount of each vertex is calculated using the position shift map, and each side of the drawing data is moved by the movement amount of the vertex to create correction drawing data. A method for creating corrected drawing data, which is characterized by being equipped with. The pattern area density map divides the drawing data for each of a plurality of drawing fields, further partitioning the drawing field into a plurality of regions, claim 17, characterized by having a pattern area density of each region is allocated The method for creating correction drawing data according to any one of 20 to 20 . The corrected drawing data creation method according to any one of claims 17 to 21 , wherein the pattern area density map divides a drawing field into a plurality of areas, and each area has an assigned pattern area density.

Images