JP3967923B2 - Pattern drawing apparatus and pattern drawing method - Google Patents

Description

Technical field
The present invention relates to a pattern drawing apparatus and a pattern drawing method used in a fine processing technique using a scanning probe microscope.
Background art
With the high integration of semiconductor electronic devices and the high density of recording media, ultrafine processing technology is required. However, in electronic devices, the minimum processing dimension is limited to about 100 nm depending on the wavelength of light used in photolithography and the lens material, and in recording media, a reduction in resolution margin is expected in a laser original recording apparatus. In recent years, as an alternative technique, for example, S.I. C. Minne et al. "Fabrication of 0.1, m metal oxide semiconductor field-effect transistor," Appl. Phys. Lett. 66 (6) 6 February 1995, pp. 703-705, or Hyfsouk. A microfabrication technique using a scanning probe microscope as shown in “Hybrid AFM / STM Lithography” (1997 SYMPOSIUM ON VLSI TECHNOLOGY) is attracting attention. The method used is high in resolution and in principle can be processed at the atomic level.
In addition, as disclosed in US Pat. No. 5,666,190, a lithography system having a plurality of cantilevers has also been proposed.
Disclosure of the invention
When a scanning probe microscope is used in a drawing apparatus, the voltage applied between the probe and the substrate must be controlled in order to keep the irradiation dose from the probe to the substrate constant. However, this control is not suitable for high-speed processing because feedback processing by closed-loop control is performed. Moreover, in practice, the processing speed is further reduced because the charge / discharge current for the stray capacitance between the probe and the substrate flows in a direction that hinders control. For this reason, enormous time is required to draw a complicated figure so as to frequently repeat ON / OFF of the current.
The present invention focuses on the fact that if the drawing distance is relatively short, the irradiation current from the probe to the substrate is kept almost constant even if a constant voltage is applied without performing feedback control. . That is, a voltage value at which a desired irradiation current is obtained by feedback is measured and stored in advance, and actual drawing is performed only by turning on / off the stored voltage value without applying feedback.
In this case, since the feedback process only needs to be performed once, for example, every predetermined drawing distance, it is possible to significantly reduce the time compared to the conventional method that always requires feedback. Furthermore, when this method is used for a drawing apparatus using a plurality of probes, it is not necessary to control the current values of the individual probes at the same time, so a complicated control system is not required, and higher speed drawing is possible. .
BEST MODE FOR CARRYING OUT THE INVENTION
Example 1
In this embodiment, an example of a pattern writing apparatus that performs writing on a resist film using a single probe will be described with reference to FIGS. 1, 2, and 3. FIG. FIG. 1 is a block diagram showing the configuration concept of the first embodiment of the drawing apparatus of the present invention. The conductive probe 2 of the drawing head unit 1 is connected to the holder 4 via the conductive spring unit 3, and the drawing target unit 5 composed of the substrate 6 coated with the resist layer 8 and the conductive layer 7 serves as the probe 2. Located opposite to each other, the drawing portion 5 is fixed to the Z driving portion 9 and the XY driving portion 10 and can be scanned in the in-plane direction and the vertical direction relative to the probe 2. . The XY drive unit 10 is connected to the Z coarse movement unit 11 and can move the probe 2 roughly in the vertical direction with respect to the drawing unit 5. The conductive layer 7 is connected to the current detection unit 13, where the current flowing from the probe 2 through the resist layer 8 is detected, and is applied from the voltage application unit 14 to the probe 2 by the control unit 12 so that a desired current value is obtained. The voltage to be adjusted is adjusted. The voltage value at this time is temporarily stored in the voltage storage unit 15, and this value can be used later. The spring portion 3 is connected to the position detection portion 16 where the relative position in the vertical direction of the probe 2 from the resist layer 8 or the force applied to both is detected, and the probe 2 is moved to a predetermined position by the control portion 12. The Z-direction displacement of the Z drive unit 9 is adjusted so that Further, the control unit 12 can move the probe 2 in the plane with respect to the resist layer 8 by displacing the XY driving unit 10. Furthermore, by reading predetermined pattern data from the input unit 17 into the control unit 12, the position and current value of the probe 2 can be controlled in accordance with the pattern data.
Next, the operation when pattern drawing is performed using the apparatus shown in FIG. 1 will be described. First, in order to bring the probe 2 and the resist layer 8 into contact with each other, the Z coarse movement portion 11 brings the two into close proximity. After sufficiently approaching, the vertical position of the probe 2 is automatically controlled by a position feedback loop comprising the position detector 16, the controller 12, and the Z drive unit 9. The pattern data is read from the input unit 17, and the control unit 12 controls the position and current value of the probe 2 based on the pattern data. Hereinafter, description will be made with reference to FIG. FIG. 2A is an example of two-dimensional pattern data. Each bit of data represents ON / OFF of the current, and the position of the data indicates the coordinates of the probe 2 on the resist layer 8. Here, the ON bit 20 is shown in black and the OFF bit 21 is shown in white. FIG. 2B shows the movement of the probe 2 on the resist layer 8 at the time of drawing. The control unit 12 performs drawing by raster scanning in accordance with the pattern data, but a voltage acquisition region 22 for obtaining a drawing voltage in advance is provided separately from the drawing region 23 in which a desired pattern is actually drawn. In the voltage acquisition region 22, a voltage value is measured while scanning the probe 2 by turning on a current feedback loop including the current detection unit 13, the control unit 12, and the voltage application unit 14 at the beginning of each scanning line 24, and stores the voltage. The voltage value is stored in the unit 15. When the probe 2 enters the drawing region 23, scanning is performed with the current feedback turned OFF, and if the probe 2 is at the drawing position 25 corresponding to each ON bit 20 of the pattern data, it is stored in the voltage storage unit 15. When the voltage value is applied for a predetermined time and is at the position corresponding to the OFF bit 21, the voltage is not applied or a voltage equal to or lower than the threshold value through which the current flows is applied. A pattern is drawn by performing this on each scanning line 24.
The pattern data does not necessarily have to be expressed by one bit of ON / OFF as shown in FIG. 2A, and may be expressed by a plurality of bits and correspond to different current values for each numerical value. In that case, in the voltage acquisition region 22, the voltage value corresponding to each current value is measured and stored in the voltage storage unit 15. The voltage value measurement in the voltage acquisition region 22 is not necessarily performed for each scanning line 24, and may be performed once for each of the plurality of scanning lines 24 or may be performed for each scanning line 24 a plurality of times. The voltage acquisition region 22 may be anywhere on the surface of the resist layer 8, but it is particularly desirable to be as close as possible to the drawing region 23. Further, since the voltage value in the voltage acquisition region 22 can be measured even in a region once used, the area of the voltage acquisition region 22 can be reduced by using the same region.
In the pattern data shown in FIG. 2A, each data position corresponds to the position of the probe 2, but drawing is performed by vector scanning using the current data and the coordinates of the probe 2 described in the pattern data. May be. Specifically, the pattern data is a set of current value data and the start point and end point coordinate data of the probe 2 arranged in the drawing order. The probe 2 moves from the start point to the end point while applying a voltage corresponding to the current value given by the pattern data, and repeats this to draw a desired pattern.
In the voltage acquisition region 22, there may be a case where a correct voltage value cannot be obtained due to some influence such as the state of the resist layer 8 or the state of the probe 2. In such a case, drawing on the scanning line 24 cannot be performed appropriately. . In order to prevent this, voltage measurement on each scanning line 24 in the voltage acquisition region 22 is performed a plurality of times, and a plurality of voltage values are stored in the voltage storage unit 15. For example, examine these voltage values in order of newness, do not use those exceeding the preset standard voltage value range, and then examine the new voltage value until an appropriate voltage value is obtained. Do. If all the voltage values are not appropriate, the voltage value used in the previous scanning line 24 stored in the voltage storage unit 15 is used. By doing so, highly reliable drawing can be performed.
In the present embodiment, the Z drive unit 9 and the XY drive unit 10 adjust the displacement by a voltage signal from the control unit 12 using a piezoelectric element. A stepping motor and a micrometer head are used as the mechanism of the Z coarse movement unit 11, but any method such as a lever type or an inchworm type may be used. Since the Z drive unit 9, the XY drive unit 10, and the Z coarse movement unit 11 are for moving the drawing head unit 1 and the drawing unit 5 relatively, they may be on either side. The position detection of the position detection unit 16 is performed by an optical lever method using reflection of laser light by the spring unit 3.
The substrate 6 is made of glass, and chromium is deposited as a conductive layer 7 from 20 nm to 100 nm, and a resist layer 8 having a thickness of about 10 nm to 100 nm (for example, a negative resist (Hitachi, which is a mixed resist of poly (vinylphenol) and azide) (Hitachi). RD2100N)) manufactured by Kasei Kogyo Co., Ltd. is applied. The resist used for the resist layer 8 may be a mixed resist of a novolak phenol resin and a photosensitizer, a chemically amplified resist, or polymethyl methacrylate. The substrate 6 can be made of any material desired to be processed, such as silicon or doped silicon. When doped silicon is used for the substrate 6, the conductive layer 7 may be omitted because the substrate 6 itself is conductive. The conductive layer 7 is connected to the current detector 13, and the current flowing through the resist layer 8 can be measured by the voltage applied to the probe 2. If the substrate 6 is conductive, the current detector 13 may be connected directly to the substrate 6. The conductive layer 7 can be used while being grounded. In this case, the current detection unit 13 is connected to the probe 2 together with the voltage application unit 14 to detect the current.
The probe 2 and the spring portion 3 are integrally formed of a silicon single crystal using, for example, a fine processing technique. These may also be silicon oxide and silicon nitride. It is appropriate that the radius of curvature of the tip of the probe 2 is 10 nm to 100 nm, the spring constant of the spring portion 3 is 0.05 N / m to 5 N / m, and the resonance frequency is 10 kHz to 50 kHz. The probe 2 is made conductive by depositing titanium having a thickness of 10 nm to 50 nm. In addition to titanium, tungsten, molybdenum, titanium carbide, tungsten carbide, molybdenum carbide, or conductive diamond may be used.
A drawing method when the surface of the substrate 6 is not flat and has a step will be described with reference to FIG. FIG. 3 is a diagram showing only the drawing portion 5 used here. When there is a step on the surface of the substrate 6, the normal drawing method not only prevents the probe 2 from entering the region immediately below the step and cannot perform drawing, but also the probe 2 may collide with the step and be damaged. In order to reduce the influence of the unevenness of the substrate 6, the planarization layer 30 is applied to the surface of the substrate 6 to planarize the surface. A conductive layer 7 and a resist layer 8 similar to those shown in FIG. Drawing is performed by the same method using a pattern drawing apparatus similar to that shown in FIG. 1, and a resist pattern is formed on the conductive layer 7 by using a ring for developing the resist layer 8. Using this resist pattern as a mask, the conductive layer 7 and the planarizing layer 30 are removed by etching or the like, whereby the pattern of the planarizing layer 30 is formed on the substrate 6. For example, a resist (for example, BLOC manufactured by Hitachi Chemical Co., Ltd.) as a planarizing layer 30 is spin-coated on a silicon substrate 6 on which a pattern has already been formed so as to have a thickness of 300 nm, and p-type silicon is deposited thereon to conduct electricity. The layer 7 is formed, and finally a resist layer 8 coated with a 40 nm-thick resist (for example, RD2100N manufactured by Hitachi Chemical Co., Ltd.) is used. After drawing, the pattern transferred to the resist layer 8 is developed, and then the conductive layer 7 is dry-etched with carbon tetrafluoride gas using the resist pattern as a mask, and the planarizing layer 30 is dry-etched with oxygen gas, for example. Thus, the pattern is transferred to the substrate 6.
In the present embodiment, the result of actual drawing will be described with reference to FIG. A conductive silicon substrate was used as the substrate 6, the resist layer 8 coated with the resist RD2100N having a thickness of 50 nm was formed, and the conductive layer 7 was omitted. The probe 2 was moved at 0.1 mm / s on the resist layer 8 and the current flowing between the probe 2 and the substrate 6 was set to 30 pA. The voltage applied at this time was around -40V.
During the formation of the latent image on the resist layer 6, the probe 2 receives a Coulomb force acting between the probe 2 and the substrate 6 by the voltage applied to create the latent image. Due to this Coulomb force, the spring portion 3 is deformed and the probe is in contact with the resist layer 8. There are portions where the latent image is not formed according to the pattern to be created. Since no current is required in a portion where a latent image is not formed, it is not necessary to apply a voltage to the probe 2 at this position. However, when the voltage is set to 0 V, the Coulomb force acting on the probe 2 is lost, so that the spring portion 3 is not deformed and is separated from the surface of the resist layer 8. Then, when a voltage is applied again at a position where a latent image is to be formed, the Coulomb force suddenly acts on the probe 2 and the spring portion 3 is suddenly deformed, so that the probe 2 is intensely applied to the resist layer 8. There is a high possibility that the probe 2 will be damaged. Therefore, when drawing a portion where a latent image is not produced, it is preferable to control the voltage so that a current that is so small that a latent image is not formed flows. In this example, when the applied voltage was -20 V or less, the current was 1 pA or less, and no latent image was formed. Therefore, the applied voltage value corresponding to the OFF bit 21 of the pattern data is set to -20V. Further, the standard voltage range for determining the drawing voltage was set to 30 V or more. The pattern shown in FIG. 4A is drawn as pattern data under the above conditions, and the resist pattern 31 obtained by developing by dipping in a 0.83% tetramethylammonium hydroxide solution for 1 minute is scanned electron. The results observed with a microscope are shown in FIG. Drawing was performed by performing raster scanning in the horizontal direction from the upper left of the figure. In the voltage acquisition region 32, the current value gradually approaches the set value by current feedback, so that it can be seen that the image is gradually drawn as scanning is performed. In the drawing area 33, the pattern data was transferred to an area of 30 μm × 30 μm. The minimum processing dimension of this pattern was 100 nm.
In this embodiment, current feedback is not always applied, but is performed for each predetermined drawing distance, and a voltage value at which a desired current can be obtained is obtained and stored. In actual drawing, the voltage value is turned on. Since only / OFF is performed, it is possible to provide a pattern drawing apparatus that draws a complex and fine figure pattern at high speed. The storage of the voltage value may be controlled so as to be executed gradually every short distance in consideration of the wear of the probe.
(Example 2)
In this embodiment, an example of a pattern drawing apparatus that performs drawing on a resist film using a plurality of probes will be described with reference to FIG. Although the present embodiment is not essentially different from the pattern drawing apparatus of the embodiment shown in FIG. 1, the difference from FIG. 1 is that a plurality of conductive probes 40a-40d arranged one-dimensionally. Are fixed to the common holder 4 via a plurality of spring portions 41a-41d, and the probes 40a-40d are independently connected to the voltage application unit 14, respectively. The voltage application unit 14 is connected to the probes 40a-40d. At the same time, the voltage can be applied independently. Further, the spring portions 41a and 41d at both ends are connected to the position detection unit 16, thereby detecting the vertical positions of the probes 40a and 40b from the surface of the resist layer 8 in the same manner as in the first embodiment. The two Z driving portions 42a and 42b are displaced based on the signals of the above, and the vertical positions of all the probes 40a to 40d are adjusted to desired values. Those common to both embodiments are indicated by the same reference numerals.
Next, the operation when pattern drawing is performed using the apparatus shown in FIG. 5 will be described. First, in order to bring the probes 40a to 40d and the resist layer 8 into contact with each other as in the first embodiment, the Z coarse movement portion 11 causes them to approach each other roughly. After sufficiently approaching, the vertical positions of the probes 40a and 40d are automatically controlled by two independent position feedback loops composed of the position detector 16, the controller 12, and the Z drivers 42a and 42b. As a result, even if the straight line connecting the tips of the probes 40a-40b and the surface of the resist layer 8 are not parallel, they are automatically adjusted so that they are parallel, and the probes 40a-40b are adjusted to the surface of the resist layer 8. Can be contacted with almost the same force.
Pattern data is prepared for each probe 40a-40d, the pattern data is read from the input unit 17, and the control unit 12 controls the position and current value of the probe 40a-40d based on this pattern data. FIG. 6 is an example of two-dimensional pattern data. The pattern data 51, 52, 53, and 54 are data used when drawing with the probes 40a to 40d, respectively. As in the first embodiment, each bit of data represents ON / OFF of the current, and the position of the data indicates the coordinates of the probe 40a-40d on the resist layer 8. Again, the ON bit 20 is shown in black and the OFF bit 21 is shown in white. FIG. 7 shows the movement of the probes 40a-40d on the resist layer 8 at the time of drawing. The scanning regions 55, 56, 57, and 58 are scanning regions of the probes 40a to 40d, and the scanning regions 55, 56, 57, and 58 are drawing regions 60, 64, 68, and 72, and four voltage acquisition regions 59a, 59b, 59c, 59d and the like.
At the beginning of each scanning line 61, 65, 69, 73, when the probes 40a-40d are scanning the voltage acquisition regions 59a, 63a, 67a, 71a, respectively, the current detection unit 13, the control unit 12, and the voltage application unit The voltage value at which a desired current is obtained is measured while scanning the probe 41 a with the current feedback loop consisting of 14 turned on, and the voltage value is stored in the voltage storage unit 15. During this time, the probes 41b, 41c, and 41d simultaneously scan the voltage acquisition regions 63a, 67a, and 71a, respectively, but apply 0V or a voltage equal to or lower than a threshold value through which a current flows. Next, when the probes 40a-40d are scanning the voltage acquisition regions 59b, 63b, 67b, 71b, respectively, the probes 41a, 41c, 41d are set to 0 V or a voltage that is equal to or lower than the threshold value at which current flows. Applying the voltage, the current feedback is turned on for the probe 41b, and the voltage value at which a desired current is obtained is measured and stored. By repeating this operation for the probes 41c and 41d, the voltage used by each of the probes 40a to 40d at the time of drawing is measured and stored. That is, the voltage value used by each probe 40a-40d is calculated | required by voltage acquisition area | region 59a, 63b, 67c, 71d, respectively. When the probes 40a-40d enter the drawing regions 60, 64, 68, 72, respectively, scanning is performed with the current feedback turned OFF, and the probes 40a-40d are scanned by the respective drawing positions 62, corresponding to the ON bit 20 of the pattern data. 66, 70, and 74, the respective voltage values stored in the voltage storage unit 15 are applied for a predetermined time, and in the position corresponding to the OFF bit 21, no voltage is applied or current flows. Apply a voltage below the threshold. A pattern is drawn by performing this on each scanning line 61, 65, 69, 73.
The pattern data drawn by each probe 40a-40d is not necessarily different as shown in FIG. 6, and the same pattern data may be drawn by a plurality of probes. In addition, the voltage acquisition region does not necessarily need to be divided for each probe. For example, the same voltage acquisition region may be scanned by the number of times of the probe, and the voltage used by each probe at the time of drawing may be obtained each time. Good. FIG. 5 shows an example in which the four probes 40a to 40d are arranged one-dimensionally. However, the number of probes is not limited, and the drawing speed increases as the number increases. The probes may be arranged two-dimensionally. In that case, the position detection for the vertical position control of the probe is performed by using a spring portion connected to three probes that are not on the same straight line, and three independent position feedbacks for each signal. The vertical position of the probe may be controlled by displacing the Z drive unit. Similarly to the first embodiment, if drawing is performed using the planarization layer 30 as shown in FIG. 3, the drawing can be performed even when the substrate 6 is uneven. The current detection unit 13 is connected to the probes 40a-40b together with the voltage application unit 14, the conductive layer 7 is grounded, and the currents flowing through the respective probes 40a-40b are independently measured, whereby each probe 40a- Current feedback may be applied independently with respect to 40d. By doing so, each of the probes 40a-40b can simultaneously measure the voltage value necessary for drawing, so that the drawing speed can be improved.
FIG. 8A is a schematic diagram of a pattern drawn using 100 probes arranged two-dimensionally. Each probe scans within each scanning region 75, and there are as many scanning regions 75 as the number of probes in the same arrangement as the probes. Further, the inside of the scanning area 75 is divided into a voltage acquisition area 76 and a drawing area 77. In this example, since the voltage measurement is performed for each scanning line, the region on the left side of the scanning region 75 is the voltage acquisition region 76. Therefore, a pattern drawn at the time of voltage measurement is left on the entire left side of the scanning region 75. On the other hand, FIG. 8B shows a case where voltage measurement is not performed at the beginning of each scanning line, but a voltage acquisition region 76 is provided at the upper left of the scanning region 75 and the probe is moved to this region to perform voltage measurement. An example is shown. In this case, since the drawing area 77 exists on the left side of the scanning area 75, the patterns adjacent to the left and right can be brought into contact with each other.
In this example, a silicon single crystal probe deposited by depositing titanium and a spring portion having 10 vertical and horizontal, ie, 100, probes arranged at intervals of 0.1 mm are used, and 50 nm is used. On a conductive silicon substrate coated with a resist RD2100N having a thickness of 30 mm, the current flowing through each probe is set to 30 pA, and each probe is 0.1 mm square at a speed of 0.1 mm / s. A pattern was drawn in an area of 1 mm square by drawing while moving the range.
(Example 3)
Next, an embodiment of a pattern drawing apparatus for drawing by rotating the substrate will be described with reference to FIG. Although the present embodiment is not essentially different from the pattern drawing apparatus of the embodiment shown in FIG. 5, it is assumed that the drawing portion 5 is rotated, and the probes 40a- 40d is arranged close to one side of the drawing portion 5. Those common to both embodiments are indicated by the same reference numerals. The main difference from the embodiment shown in FIG. 5 is that the drawing unit 5 is fixed on the rotary stage 80, and the rotary stage 80 is rotated by the rotary drive unit 82 according to a control signal from the control unit 12. It is that it is rotated through. Further, the Z driving units 42a and 42b, the XY driving unit 10 and the Z coarse movement unit 11 for moving the probes 40a to 40d relative to the resist layer 8 are attached to the drawing head unit 1 side. A current detection unit 13 is connected to the voltage application unit 14, and the voltage applied between the grounded conductive layer 7 and the probes 40 a to 40 d and the detection of the current can be independently performed.
Prior to drawing, first, the probe 40 a-40 d is brought closer to the surface of the resist layer 8 using the Z coarse movement portion 11. After sufficiently approaching, the signals from the spring parts 41a and 42d are detected using the position detection unit 16, and searched by two independent position feedback loops comprising the position detection unit 16, the control unit 12, and the Z drive units 42a and 42b. The vertical position of the needles 40a and 40d is automatically controlled. Thereby, all the probes 40a-40b can be brought into contact with the surface of the resist layer 8 with a substantially uniform force. Thereafter, the rotary stage 80 is rotated by the rotary drive unit 82. Drawing is performed by applying a voltage from the voltage application unit 14 to each of the probes 40a to 40d. The value of the current flowing between each of the probes 40a to 40d and the conductive layer 7 is expressed as a current at every fixed drawing distance. The voltage value is adjusted by feedback, the voltage value at that time is stored in the voltage storage unit 15, feedback is stopped for actual drawing, and the stored voltage value is output according to the pattern data read from the input unit 17. To do. The voltage value measurement may be performed every time each of the probes 40a to 40d draws the same distance, but may be performed at every fixed rotation angle of the rotary stage 80. In this case, although the drawing distance changes at a time in proportion to the distance from the rotation center of each probe 40a-40d, the voltage values of all the probes 40a-40d can be measured simultaneously. The area used for voltage measurement can be reduced by slowing the rotation speed.
A concentric pattern can be drawn by displacing the XY drive unit 10 each time the rotary stage 80 makes a round and moving the probes 40a-40d by a certain distance in the radial direction of rotation. Further, when the probes 40a-40d are moved at a constant speed in the radial direction according to the rotation angle of the rotary stage 80, a spiral pattern can be formed. Although FIG. 9 shows an example in which the four probes 40a to 40d are arranged one-dimensionally, one probe may be used. The number of probes is not limited, and the drawing speed increases as the number increases. The probes may be arranged two-dimensionally. In that case, the position detection for the vertical position control of the probe is performed by using a spring portion connected to three probes that are not on the same straight line, and three independent position feedbacks for each signal. The vertical position of the probe may be controlled by displacing the Z drive unit. As in the second embodiment, by using the planarizing layer 30, it is possible to draw on the substrate 6 with unevenness without any trouble. A master disk of an optical disk can be manufactured by drawing a dot pattern corresponding to data information and address information in a circular shape by the pattern drawing apparatus of this embodiment.
In order to facilitate understanding of the present invention, reference numerals are briefly described below.
DESCRIPTION OF SYMBOLS 1 ... Drawing head part, 2, 40a, 40b, 40c and 40d ... Probe, 3, 41a, 41b, 41c and 41d ... Spring part, 4 ... Holder, 5 ... Drawing part, 6 ... Substrate, 7 ... Conductive layer , 8... Resist layer, 9, 42 a and 42 b... Z drive unit, 10... XY drive unit, 11... Z coarse movement unit, 12 ... control unit, 13 ... current detection unit, 14 ... voltage application unit, 15. Part, 16 ... position detection part, 17 ... input part, 20 ... ON bit, 21 ... OFF bit, 22, 32, 59a, 59b, 59c, 59d, 63a, 63b, 63c, 63d, 67a, 67b, 67c, 67d , 71a, 71b, 71c, 71d and 76 ... voltage acquisition region, 23, 33, 60, 64, 68, 72 and 77 ... drawing region, 24, 61, 65, 69 and 73 ... scanning lines, 25, 62, 66 , 7 And 74 ... drawing position, 30 ... flattening layer, 31 ... resist pattern, 51, 52, 53 and 54 ... pattern data, 55, 56, 57, 58 and 75 ... scanning region, 80 ... rotating stage, 81 ... rotating axis 82: Rotation drive unit.
Industrial applicability
According to the present invention, instead of constantly applying current feedback, a voltage value for obtaining a desired current is obtained and stored before pattern drawing, and drawing is performed only by ON / OFF of the voltage value stored at that time. By performing the above, a complicated pattern can be drawn at high speed. Further, by using a plurality of probes, it is possible to perform drawing at higher speed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration concept of an embodiment of a pattern drawing apparatus of the present invention.
2A is an example of pattern data used for drawing, and FIG. 2B is a plan view showing the operation of the probe on the resist layer and the state of drawing.
FIG. 3 is a cross-sectional view of a substrate into which a planarization layer is introduced for drawing on an uneven substrate.
FIG. 4A is a scanning electron micrograph of the resist layer developed after drawing using the pattern data used in the example, and FIG. 4B is the data of FIG. 4A.
FIG. 5 is a block diagram showing a concept of an embodiment of a pattern drawing apparatus using a plurality of probes according to the present invention.
FIG. 6 shows an example of pattern data used for drawing.
FIG. 7 is a plan view showing the operation of each probe on the resist layer and the state of drawing.
FIG. 8 is a schematic diagram of an example of a pattern drawn using a plurality of probes.
FIG. 9 is a block diagram showing an example configuration concept of a pattern drawing apparatus for drawing by rotating the substrate of the present invention.

Claims (19)

A pattern drawing apparatus that scans the surface of a substrate with a probe and draws a desired pattern on the substrate by supplying a current between them,
An input section for reading pattern data;
Based on the pattern data, a current value supplied between the probe and the substrate, and a control unit for determining a supply position of the current;
A voltage storage unit that stores a voltage value when the current value is obtained by applying a voltage while scanning a probe outside the pattern drawing region on the substrate;
A pattern drawing apparatus comprising: a voltage applying unit that applies the voltage value at the current supply position while scanning a probe in a pattern drawing region on the substrate to supply a current. The pattern drawing apparatus according to claim 1,
The pattern drawing apparatus, wherein the pattern data is represented by bits representing ON / OFF of current, and the position of each bit indicates the coordinates of the probe on the substrate. The pattern drawing apparatus according to claim 1,
The pattern data is represented by one or more bits corresponding to a current value, and the position of each bit indicates the coordinates of the probe on the substrate,
The control unit determines a current value supplied between the probe and the substrate based on the plurality of bits, a position of the bit data, and a supply position of the current. . The pattern drawing apparatus according to claim 1,
The pattern drawing apparatus, wherein the pattern data includes the current value data and the coordinate data of the probe. The pattern drawing apparatus according to claim 4,
The pattern coordinate apparatus is characterized in that the coordinate data of the probe consists of a set of coordinate data of the start point and end point of scanning of the probe. The pattern drawing apparatus according to claim 1,
The voltage drawing is stored every time a predetermined distance pattern is drawn. The pattern drawing apparatus according to claim 1,
The pattern drawing apparatus is characterized in that the voltage value is stored for each scanning line. The pattern drawing apparatus according to claim 1,
The pattern drawing apparatus, wherein the voltage value is stored in a voltage acquisition area that has already been used. The pattern drawing apparatus according to claim 1,
A standard voltage value range is set in advance, voltage measurement is performed a plurality of times on one scanning line, each voltage value is stored in the voltage storage unit, and the standard voltage value is sequentially measured from a voltage value closer to the drawing area. When the voltage value is within the range, this is set as a voltage value applied during pattern drawing, and when the voltage value is out of the range, the voltage value measured at the next position is A pattern drawing apparatus characterized by comparing with a range. It is a pattern drawing apparatus of Claim 9, Comprising:
When the plurality of voltage values are out of a range of standard voltage values, a voltage value used for pattern drawing is applied by a previous scanning line. The pattern drawing apparatus according to claim 1,
A pattern drawing apparatus, wherein a voltage smaller than the voltage value is applied outside the current supply position. Forming a first resist film on the main surface of the substrate;
Forming a conductive layer on the first resist film;
Forming a second resist film on the conductive layer;
Determining a current value to be supplied between the probe and the conductive layer based on pattern data, and a supply position of the current;
Applying a voltage while scanning a probe outside the pattern drawing region on the second resist film, and storing the voltage value when the current value is obtained;
Applying the voltage value at the current supply position while scanning the probe on the second resist film, and drawing the pattern on the second resist film;
Forming a desired pattern on the substrate by etching the first resist film and the conductive layer using the second resist film on which the pattern is drawn as a mask. A pattern drawing apparatus for drawing a desired pattern by supplying a current between the probe and the substrate while scanning the surface of the substrate with a probe,
A pattern data input unit, a plurality of probes, a voltage application unit that applies a voltage between each probe and the substrate and supplies a current, and a current value that flows between each probe and the substrate A current measuring unit for measuring, a voltage storage unit for storing a voltage value for each probe when the measured current value becomes a current value determined based on the pattern data, and each stored voltage value A pattern drawing apparatus comprising: a control unit that controls the voltage application unit so that each probe is applied at an application position determined based on drawing pattern data. It is a pattern drawing apparatus of Claim 13, Comprising:
The substrate has a voltage acquisition region for determining the voltage value, the voltage acquisition region includes a voltage acquisition partial region for each probe, and the current value is measured in the corresponding voltage acquisition partial region for each probe. And determining a voltage value for each probe. It is a pattern drawing apparatus of Claim 13, Comprising:
The substrate has a voltage acquisition region for determining the voltage value, and scans the same voltage acquisition region with each probe to determine a voltage value for each probe. . It is a pattern drawing apparatus of Claim 13, Comprising:
The pattern drawing apparatus, wherein the plurality of probes are arranged two-dimensionally. A probe, a stage on which a substrate to be drawn is mounted, a rotation drive unit that rotates the stage, a voltage application unit that applies a voltage between the probe and the substrate to flow a current, the probe, and the probe A current measurement unit that measures a current value flowing between the substrate, a voltage storage unit that stores a voltage value when a current value determined based on drawing pattern data is obtained by the current measurement unit, and the voltage application A pattern drawing apparatus comprising: a control unit that controls a unit to apply a determined voltage value at a voltage application position determined based on the drawing pattern data. The drawing apparatus according to claim 17,
The pattern drawing apparatus is characterized in that the voltage value is stored every time a predetermined distance is drawn. The drawing apparatus according to claim 17,
The pattern drawing apparatus, wherein the voltage value is measured for each predetermined rotation angle.

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