JP2009140974A - Drawing method and drawing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drawing method and a drawing device, which can carry out drawing while changing an irradiation amount of a beam to a material to be drawn in accordance with density information or color information included in bit map data. <P>SOLUTION: A data processing system 21 is internally provided with: a means for extracting density information or color information of each pixel in the bit map data; a table containing a beam irradiation amount corresponding to density information or color information of each pixel; a means for finding a beam irradiation amount for each pixel corresponding to density information or color information by reference to the table; a means for calculating an irradiation time of a beam corresponding to a beam irradiation amount of each pixel; and a means for generating beam scan signal information based upon a deflection voltage of a beam and an irradiation time corresponding to each pixel. A CPU 10 controls a scan with the beam based upon the beam scan signal information to perform drawing processing using the beam on the material to be drawn. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a drawing method and a drawing apparatus using a beam such as an electron beam.

  In a drawing apparatus that performs drawing processing by irradiating an electron beam corresponding to a desired pattern to be drawn (drawing pattern) on a drawing material such as a mask substrate or a semiconductor substrate coated with a resist that is sensitive to an electron beam, There is an apparatus that performs drawing according to bitmap data corresponding to a drawing pattern.

  FIG. 1 is a diagram showing the configuration of such a drawing apparatus. In the figure, an electron beam (electron beam) 15 is emitted toward the drawing material 9 from the electron source 1 installed at the upper end of the apparatus column 7. The drawing material 9 is placed on the stage 6 in the sample chamber 8 for accommodating the drawing material. The stage 6 includes a moving mechanism for moving the drawing material 9 in each direction of the X direction and the Y direction along the horizontal plane (the X direction and the Y direction are orthogonal to each other).

  The lower end of the apparatus column 7 and the upper end of the sample chamber 8 communicate with each other, and the apparatus column 7 and the sample chamber 8 are evacuated by a vacuum exhaust system provided separately. Thereby, the degree of vacuum can be individually set for the internal atmosphere of the apparatus column 7 and the internal atmosphere of the sample chamber 8.

  The electron beam 15 emitted from the electron source 1 is focused by the electron lens 2 b in the electron source column 2 provided in the apparatus column 7. The electron beam 15 thus focused passes through the electron optical system 3 in the apparatus column 7.

  The electron optical system 3 includes two intermediate lenses 3b and 3c located on the upper side and an objective lens 3d located on the lower side. The electron beam 15 is focused on the drawing material 9 by the lens action of the lenses 3b to 3d.

  Further, the electron beam 15 is appropriately deflected by the deflection action of the deflection electrode 5. Thereby, the electron beam 15 is sequentially irradiated to each predetermined position on the drawing material 9. At this time, the irradiation time of the electron beam at each position is adjusted by the application holding time of each deflection voltage applied to the deflection electrode 5 corresponding to each position.

  A blanking electrode 4 is provided between the intermediate lens 3c and the objective lens 3d. When the blanking electrode 4 operates, the electron beam 15 is greatly deflected and bent between the intermediate lens 3c and the objective lens 3d, and the irradiation of the electron beam 15 onto the drawing material 9 is blocked.

  Here, the electron source 1 is driven and controlled by the electron source control system 1a. The electron source barrel 2 is driven and controlled by an electron source barrel control system 2a. The electron optical system 3 is driven and controlled by an electron optical system control system 3a. The blanking electrode 4 is driven and controlled by a blanking control system 4a. The deflection electrode 5 is driven and controlled by a beam scanning control system 5a. The stage 6 is driven and controlled by a stage drive control system 6a.

  The control systems 1a to 6a are connected to a CPU 10 that controls the entire apparatus. Further, a data processing system 11 is connected to the CPU 10. The CPU 10 controls the control systems 1 a to 6 a and the data processing system 11.

  The data processing system 11 includes a data input unit 11c to which external data is input, a data conversion unit 11b that performs data conversion processing based on a data signal from the data input unit 11c, and a data conversion unit 11b. A data output unit 11a that outputs data to the CPU 10 is provided.

  In the drawing apparatus having such a configuration, monochrome binary bitmap data is input to the data input unit 11c of the data processing system 11 as shown in FIG.

  In the data processing system 11, the monochrome binary bitmap data is sent to the data conversion unit 11b via the data input unit 11c.

  Based on the data, the data converter 11b generates scanning signal information of the electron beam 15 corresponding to binary information in each pixel (pixel) in the bitmap data. The scanning signal information is output to the CPU 10 via the data output unit 11.

  The CPU 10 controls the electron source control system 1a, the electron source barrel control system 2a, the electron optical system control system 3a, and the stage drive control system 6a, and also controls the blanking control system 4a and beam scanning based on the scanning signal information. The control system 5a is controlled to perform drawing processing with the electron beam 15 on the drawing material 9 on the stage 6.

  At this time, for example, when a positive resist is applied on the drawing material 9, the position on the drawing material 9 corresponding to the pixel that is white information in the bitmap data is the position. The resist is controlled by the CPU 10 so that the electron beam 15 is irradiated so that the resist is sufficiently exposed to light. Further, blanking is performed at a position on the drawing material 9 corresponding to the pixel having black information so that the resist at that position is not exposed to the electron beam 15.

  Note that the drawing apparatus that performs the drawing process based on the monochrome binary bitmap data as described above includes a blanking operation confirmation unit for confirming whether or not the blanking operation is correctly performed corresponding to the bitmap. There is also a device (see Patent Document 1).

JP-A-8-250404

  Since the rendering apparatus having the above configuration targets only bitmap data that has been binarized in black and white, when inputting bitmap data including halftone density information and multicolor information, a predetermined threshold value is set. Thus, black and white binary conversion had to be performed in advance.

  For this reason, it has been impossible to perform drawing processing in which halftone density information and multicolor information are reflected as they are.

  The present invention has been made in view of such a point, and can perform drawing by changing the beam irradiation amount to the drawing material according to density information or color information included in the bitmap data. It is an object to provide a method and a drawing apparatus.

  A first drawing method according to the present invention is a drawing method for drawing on a drawing material by a beam based on bitmap data corresponding to a pattern to be drawn, and density information on each pixel in the bitmap data. Alternatively, the drawing is performed by changing the beam irradiation amount to the drawing material according to the color information.

  A second drawing method according to the present invention is a drawing method for drawing on a drawing material by a beam based on bitmap data corresponding to a pattern to be drawn. In the drawing method, density information on each pixel in the bitmap data Alternatively, a step of extracting color information, a step of obtaining a beam irradiation amount in each pixel according to density information or color information with reference to a table, and a step of calculating a beam irradiation time corresponding to the beam irradiation amount in each pixel And a step of generating beam scanning signal information based on the beam deflection voltage and irradiation time corresponding to each pixel, and controlling the beam scanning based on the beam scanning signal information, thereby drawing on the drawing material by the beam. And a process of performing a process.

  A first drawing apparatus according to the present invention is a drawing apparatus that performs drawing on a drawing material with a beam based on bitmap data corresponding to a pattern to be drawn. In the drawing apparatus, density information on each pixel in the bitmap data is provided. Alternatively, the drawing is performed by changing the beam irradiation amount to the drawing material according to the color information.

  According to a second drawing apparatus of the present invention, in a drawing apparatus that performs drawing on a drawing material with a beam based on bitmap data corresponding to a pattern to be drawn, density information on each pixel in the bitmap data Alternatively, a means for extracting color information, a table in which the beam dose corresponding to the density information or color information in each pixel is stored, and the beam dose in each pixel corresponding to the density information or color information with reference to the table Means for calculating a beam irradiation time corresponding to the beam irradiation amount in each pixel, means for generating beam scanning signal information based on the beam deflection voltage and irradiation time corresponding to each pixel, and a beam Means for controlling the scanning of the beam based on the scanning signal information, and thereby performing a drawing process with the beam on the drawing material. To.

  In the first drawing method and the first drawing apparatus according to the present invention, drawing is performed by changing the beam irradiation amount to the drawing material in accordance with density information or color information in each pixel in the bitmap data. .

  In the second drawing method and the second drawing apparatus according to the present invention, density information or color information in each pixel in the bitmap data is extracted, and the density information or the color information is determined by referring to the table. The beam irradiation amount in each pixel is obtained, beam scanning signal information is generated based on the beam deflection voltage and irradiation time corresponding to each pixel, and the beam scanning is controlled based on the beam scanning signal information. A drawing process is performed on the drawing material.

  Thereby, it is possible to perform a drawing process in which intermediate density information and multicolor information included in the bitmap data are reflected as they are.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing the configuration of the drawing apparatus according to the present invention. 2, the same components as those shown in FIG. 1 are denoted by the same reference numerals.

  In the present embodiment, the configuration other than the data processing system 21 is the same as that shown in FIG. Here, the electron source 1, the electron source barrel 2, the electron optical system 3, the blanking electrode 4, and the deflection electrode 5 are installed in the apparatus barrel 7 in the same manner as the configuration shown in FIG. 1. Similarly, the stage 6 on which the drawing material 9 is placed is installed in the sample chamber 8.

  Further, similarly to the configuration shown in FIG. 1, the electron source 1, the electron source barrel 2, the electron optical system 3, the blanking electrode 4, the deflection electrode 5, and the stage 6 are respectively controlled by corresponding control systems 1 a to 6 a. Driven and controlled.

  Each control system 1a-6a is connected to CPU10 which controls the whole apparatus. The CPU 10 is connected to a data processing system 21 different from the configuration shown in FIG. The CPU 10 controls the control systems 1 a to 6 a and the data processing system 21.

  The data processing system 21 performs data conversion processing based on a data input unit 21c to which data from the outside is input, a storage unit 21d, a data signal from the data input unit 11c, and a data signal from the storage unit 21d. A data conversion unit 21b that performs data output and a data output unit 21a that outputs data to the CPU 10 based on a data signal from the data conversion unit 21b are provided.

  The storage unit 21d stores a table in which electron beam dose data for each density information or color information in bitmap data corresponding to a pattern to be drawn is designated.

  An example of the table has a configuration as shown in FIG. That is, in this example, electron beam dose data for each density information is specified, D1 as electron beam dose data (dose) for density number 1, D2 as electron beam dose data for density number 2, and density D3 is designated as electron beam dose data for number 3, and D4 is designated as electron beam dose data for density number 4.

  As shown in FIG. 3A, the density information increases in density from density number 1 to density number 4 and shifts from white to black. In this example, for convenience of explanation, density information (density number) in a 4-gray gray scale from density number 1 to density number 4 is set, but actually, more density information is set. In addition, electron beam dose data for each concentration information can be set.

  For example, density information in a 16 gradation gray scale, a 256 gradation gray scale, or the like can be set.

  Here, when the resist applied on the drawing material 9 is a positive resist, the dose of the electron beam 15 to the resist gradually increases as the density number 1 shifts to the density number 4. Set to decrease. Then, if the electron beam dose in the electron beam dose data D4 for the density number 4 is set to 0 (zero), blanking is performed by the blanking electrode 4 in order to eliminate irradiation of the electron beam 15 to the resist. Thereby, the irradiation of the electron beam 15 to the resist is blocked.

  In the following description, for convenience of explanation, it is assumed that a positive resist is applied on the drawing material 9.

  The data processing system 21 has the above-described configuration, and the data conversion unit 21b refers to the table in the storage unit 21d for each pixel in the bitmap data input via the data input unit 21c, A unique electron beam dose corresponding to the pixel density information is obtained.

  Further, for each pixel, the data conversion unit 21b calculates the deflection voltage and irradiation time of the electron beam 15 corresponding to each pixel from the coordinate value and the electron beam irradiation amount obtained for the pixel, and the calculation result From this, scanning signal information (beam scanning signal information) is generated. Here, the deflection holding time at each deflection voltage corresponds to the irradiation time at that time.

  This scanning signal information is sent to the CPU 10 via the data output unit 21a. Based on the scanning signal information, the CPU 10 outputs a scanning control signal to the beam scanning control system 5a and outputs a blanking control signal to the blanking control system 4a.

  In the example of FIG. 3, the density information is an example. However, in the case of the color information, for example, a number is assigned to each specific color, and d1 as electron beam irradiation data for the color number 1 Each color information is set so that d2 is designated as electron beam dose data for color number 2, d3 is designated as electron beam dose data for color number 3, d4 is designated as electron beam dose data for color number 4, and the like. It becomes. In this case, four gradation colors are used, but other gradation colors such as 16 gradation colors and 256 gradation colors can be set.

  A drawing method executed using the drawing apparatus having such a configuration will be described below with reference to FIG.

  Bit map data including halftone density information is input to the data input unit 21 c of the data processing system 21. In the data processing system 21, the bitmap data is sent to the data conversion unit 21b via the data input unit 21c. The data converter 21b extracts density information for each pixel from the data (step S1).

  Furthermore, the data conversion unit 21b obtains a unique electron beam irradiation amount (beam irradiation amount) corresponding to the density information of each pixel in the data by referring to the table in the storage unit 21d. Thereby, the electron beam irradiation amount in each pixel is calculated | required (step S2).

  Then, the data conversion unit 21b calculates the deflection voltage and irradiation time of the electron beam 15 in each pixel from the coordinate value in each pixel in the bitmap data and the electron beam irradiation amount. That is, the deflection voltage of the electron beam 15 corresponding to each pixel is obtained from each coordinate value. Further, the irradiation time during which the electron beam 15 should be irradiated to each pixel is obtained from the electron beam irradiation amount in each pixel (step S3).

  This irradiation time corresponds to the holding time of the deflection voltage of the electron beam 15 corresponding to the pixel. In other words, the deflection voltage corresponding to the coordinate value of the pixel is held for the pixel for a predetermined time, so that the drawing object corresponding to the pixel is drawn in a state where the electron beam 15 is deflected according to the deflection voltage. Irradiation is performed while remaining at the irradiation position on the material 9.

  Further, the data converter 21b generates scanning signal information from each deflection voltage and each irradiation time obtained in this way (step S4).

  This scanning signal information is referred to when the CPU 10 creates a scanning control signal sent from the CPU 10 to the beam scanning control system 5a and a blanking control signal sent from the CPU 10 to the blanking control system 4a.

  The scanning signal information is sent to the CPU 10 via the data output unit 21a. Based on the scanning signal information, the CPU 10 creates a scanning control signal and outputs it to the beam scanning control system 5a. At the same time, the CPU 10 creates a blanking control signal based on the scanning signal information and outputs the blanking control signal to the blanking control system 4a.

  At the same time, the CPU 10 controls the electron source control system 1a, the electron source barrel control system 2a, the electron optical system control system 3a, and the stage drive control system 6a.

  As a result, the electron beam 15 emitted from the electron source 1 is irradiated onto the drawing material 9 on the stage 6.

  At this time, the beam scanning control system 5 a drives and controls the deflection electrode 5 based on the scanning control signal sent from the CPU 10. At the same time, the blanking control system 4a drives and controls the blanking electrode based on the blanking control signal sent from the CPU 10.

  Here, the scanning signal information reflects density information at each pixel in the bitmap data (the density information corresponds to the irradiation time of the electron beam 15). If the electron beam dose is set to 0 (zero) in the pixel having the highest density information corresponding to black (in the example shown in FIG. 3, the density number 4 corresponds), the blanking control system 4 a By driving, blanking of the electron beam 15 by the blanking electrode 4 is executed. Note that the blanking of the electron beam 15 is not performed for other pixels (pixels corresponding to density numbers 1 to 3 in the example shown in FIG. 3).

  The scanning control signal is a control signal for each pixel so that the irradiation time of the electron beam 15 becomes shorter as the density information corresponding to white shifts from density information having the lowest density to density information having a higher density. Yes.

  Thereby, scanning and blanking control of the electron beam 15 applied to the resist on the drawing material 9 is executed, and a predetermined drawing process is performed on the drawing material 9 (step S5).

  Here, for example, when the bitmap data corresponding to the pattern to be drawn is the letter “a” character pattern having a halftone density (see the bitmap data in FIG. 2), FIG. 4 shows an example of three-dimensional processing of the resist on the processed drawing material 9.

  Further, the three-dimensional processing by such drawing processing can be applied to the manufacture of a Fresnel lens, for example.

  In the above example, the electron beam irradiation amount to the drawing material 9 is changed according to the density information in the bitmap data, but the drawing material 9 is changed according to the color information in the bitmap data. The electron beam irradiation amount may be changed.

  In addition, at least a part of the data processing system 21 can be constituted by a PC (personal computer) or a workstation.

  As described above, the drawing method according to the present invention is a drawing method in which drawing is performed on the drawing material 9 by the beam 15 based on the bitmap data corresponding to the pattern to be drawn, in each pixel in the bitmap data. Drawing is performed by changing the beam irradiation amount to the drawing material 9 in accordance with density information or color information.

  In this case, the data conversion unit 21b in the data processing system 21 refers to a table in which the beam irradiation amount corresponding to density information or color information in each pixel is stored. Then, the data conversion unit 21b calculates the beam deflection voltage and irradiation time corresponding to each pixel, and performs drawing by changing the beam irradiation amount to the drawing material 9 based on this.

  Further, the drawing method according to the present invention is a drawing method for drawing on the drawing material 9 by a beam based on bitmap data corresponding to a pattern to be drawn. In the drawing method, density information on each pixel in the bitmap data or A step of extracting color information, a step of obtaining a beam irradiation amount in each pixel according to density information or color information with reference to a table, and a step of calculating a beam irradiation time corresponding to the beam irradiation amount in each pixel The step of generating beam scanning signal information based on the beam deflection voltage and the irradiation time corresponding to each pixel, and the scanning of the beam based on the beam scanning signal information are controlled, thereby drawing on the drawing material 9 by the beam. And a process of performing the processing.

  Furthermore, the drawing apparatus according to the present invention is a drawing apparatus that performs drawing on the drawing material 9 by a beam based on bitmap data corresponding to a pattern to be drawn. Drawing is performed by changing the beam irradiation amount to the drawing material 9 according to the color information.

  In this case, a table in which the beam irradiation amount corresponding to density information or color information in each pixel is stored is provided in the storage unit 21d in the data processing system 21, and the drawing material 9 is referred to the table by referring to the table. Drawing is performed by changing the beam irradiation amount.

  A means (data conversion unit 21b) for calculating a beam deflection voltage and an irradiation time corresponding to each pixel by referring to the table is provided, and a beam irradiation amount to the drawing material 9 based on the calculation result. Drawing is performed by changing.

  Further, the drawing apparatus according to the present invention is a drawing apparatus that performs drawing on the drawing material 9 by a beam based on bitmap data corresponding to a pattern to be drawn. In the drawing apparatus, density information on each pixel in the bitmap data or Means for extracting color information (data conversion unit 21b), a table (in the storage unit 21d) in which the beam dose corresponding to density information or color information in each pixel is stored, and density information or Means (data conversion unit 21b) for obtaining a beam irradiation amount in each pixel according to color information, means (data conversion unit 21b) for calculating a beam irradiation time corresponding to the beam irradiation amount in each pixel, and for each pixel Means (data converter 21b) for generating beam scanning signal information based on the corresponding beam deflection voltage and irradiation time, and beam scanning; No. controls scanning of the beam on the basis of the information, thereby characterized by a means for performing drawing processing by the beam to be drawn material (CPU 10, etc.).

  In the present invention, with such a configuration, multi-density or multi-color bitmap data can be input, so that the step of monochrome binary conversion can be omitted.

  In addition, since the electron beam irradiation amount to the drawing material can be changed according to the density or color of the bitmap data, it is particularly excellent in the ability to express data having a complex gradation such as a photograph.

  Further, since the electron beam irradiation amount to the drawing material can be changed according to the density or color of the bitmap data, it is effective for three-dimensional processing of the electron beam resist.

It is a figure which shows the structure of the drawing apparatus in a prior art. It is a figure which shows the structure of the drawing apparatus in this invention. In this invention, it is a figure which shows an example etc. of the table stored. It is a figure which shows the flowchart for demonstrating the drawing method in this invention. It is a figure which shows an example of the resist three-dimensionally processed by the drawing method in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electron source, 1a ... Electron source control system, 2 ... Electron source lens barrel, 2a ... Electron source lens barrel control system, 2b ... Electron lens, 3 ... Electron optical system, 3a ... Electron optical system control system, 3b, 3c ... intermediate lens, 3d ... objective lens, 4 ... blanking electrode, 4a blanking control system, 5 ... deflection electrode, 5a ... beam scanning control system, 6 ... stage, 6a ... stage drive control system, 7 ... device barrel, 8 ... Sample chamber, 9 ... Draw material, 10 ... CPU, 21 ... Data processing system, 21a ... Data output unit, 21b ... Data conversion unit, 21c ... Data input unit, 21d ... Storage unit

Claims (8)

A drawing method for drawing on a drawing material by a beam based on bitmap data corresponding to a pattern to be drawn, wherein drawing is performed according to density information or color information at each pixel in the bitmap data A drawing method, wherein drawing is performed by changing a beam irradiation amount to a material. 2. The drawing is performed by referring to a table storing a beam irradiation amount corresponding to density information or color information in each pixel and changing the beam irradiation amount to the drawing material based on the table. Drawing method. 3. The drawing method according to claim 2, wherein a drawing time is calculated by calculating a beam irradiation time corresponding to each pixel by referring to the table, and changing a beam irradiation amount to the drawing material based on the irradiation time. A drawing method for drawing on a drawing material by a beam based on bitmap data corresponding to a pattern to be drawn, the step of extracting density information or color information at each pixel in the bitmap data; A step of obtaining a beam irradiation amount at each pixel according to density information or color information with reference to a table, a step of calculating a beam irradiation time corresponding to the beam irradiation amount at each pixel, and a beam irradiation amount corresponding to each pixel A step of generating beam scanning signal information based on the deflection voltage and the irradiation time, and a step of controlling the beam scanning based on the beam scanning signal information, thereby performing a drawing process with the beam on the drawing material. Characteristic drawing method. A drawing device that draws on a drawing material by a beam based on bitmap data corresponding to a pattern to be drawn, and is drawn according to density information or color information at each pixel in the bitmap data A drawing apparatus characterized in that drawing is performed by changing a beam irradiation amount to a material. 6. A table in which a beam irradiation amount corresponding to density information or color information in each pixel is stored, and drawing is performed by changing the beam irradiation amount to the drawing material with reference to the table. The drawing apparatus described. 7. The apparatus according to claim 6, further comprising means for calculating a beam irradiation time corresponding to each pixel by referring to the table, and performing drawing by changing a beam irradiation amount to the drawing material based on the calculation result. The drawing apparatus described. A drawing device for drawing on a drawing material by a beam based on bitmap data corresponding to a pattern to be drawn, and means for extracting density information or color information in each pixel in the bitmap data; A table storing beam irradiation amounts according to density information or color information at each pixel; means for obtaining beam irradiation amounts at each pixel according to density information or color information with reference to the table; and beam at each pixel Means for calculating a beam irradiation time corresponding to the irradiation amount; means for generating beam scanning signal information based on the beam deflection voltage and irradiation time corresponding to each pixel; and beam scanning based on the beam scanning signal information. And a means for performing a drawing process using a beam on the drawing material.

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