JPH0683037A - Apparatus for inspecting shape defect of reticule mask - Google Patents

Abstract

PURPOSE:To provide the apparatus for inspecting the shape defects of a reticule mask which can deal even with the reticule mask inspection after 256M bits. CONSTITUTION:The sectional shapes of the light shielding chromium film patterns on the reticule mask 12 are measured by a stylus micrometer consisting of a cantilever which is a spring-like thin film and is fixed at the base end part, a probe which is mounted to the front end of the cantilever, for example, a displacement detecting mechanism 16 of an optical lever system which irradiates the front end of the cantilever with light by a light projector for condensing the light to a microspot and measures the bend of the cantilver by detecting the reflected light thereof with a light receiving element, and an actuator which drives the displacement detecting mechanism 16 to bring the probe into proximity to the mask while moving a sample base 11 in X, Y directions. The first signal corresponding to the pattern to be inspected of the reticule mask 12 is determined and the shapes or defects of the reticule mask are inspected by comparing the signal and the second signal based on the design data at the time of forming the reticule mask patterns.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reticle mask shape defect inspection apparatus.

[0002]

2. Description of the Related Art Conventionally, in a shape defect inspection apparatus for inspecting a pattern formed on a reticle mask, the mask formed on the mask obtained by irradiating the mask with light and moving the light irradiation position on the mask. The first signal corresponding to the inspection pattern and the second signal obtained based on the design data for forming the pattern to be inspected are compared and collated to inspect whether the shape of the pattern is correct or defective. . That is, the shape and correctness of the pattern and the size of the defect pattern are recognized by comparing the first and second signals, and the shape and the size of the defect are compared with an allowable value. Conducts an inspection that it is not judged to be abnormal because the pattern is not adversely affected even if the pattern is transferred from the reticle to the wafer.

However, this type of device has the following problems. That is, since light can be focused only up to the wavelength of light in principle, the measurement resolution is only about 1 micron and it cannot be applied to future reticle mask inspection of 256 Mbits or later.

[0004]

DISCLOSURE OF THE INVENTION The object of the present invention is 25
An object of the present invention is to provide a reticle mask shape defect inspection apparatus which can also support reticle mask inspection of 6 Mbits or later.

[0005]

The gist of the present invention is to measure the cross-sectional shape of a light-shielding chromium film pattern on a reticle mask by a stylus profilometer, specifically, an atomic force microscope, and obtain the cross-sectional shape and design data. And to perform more accurate shape and defect inspection.
By using the atomic force microscope, the cross-sectional shape of the light-shielding chromium film pattern on the reticle mask can be measured with a measurement resolution of nm order.

That is, according to the present invention, the cross-sectional shape of the light-shielding chromium film pattern on the reticle mask is formed of a spring-like thin film,
A cantilever whose base end is fixed to a fixed end, a probe attached to the tip of this cantilever, and, for example, a light projector that focuses light into a minute spot irradiates the tip of the cantilever with light and reflects it. A stylus profilometer that consists of an optical lever type displacement detection mechanism that detects light by a light receiving element and measures the bending of the nuclear cantilever, and an actuator that drives the displacement detection mechanism in the direction of bringing the nuclear probe closer to the mask. When the reticle mask is formed to obtain a first signal corresponding to the pattern to be inspected formed on the reticle mask by measuring while moving the sample table on which the reticle mask is placed in the X and Y directions. It is characterized in that the shape or the defect of the reticle mask is inspected by comparing with the second signal obtained based on the design data.

[0007]

According to the present invention, the cross-sectional shape of the light-shielding chromium film pattern on the reticle mask is determined by a stylus profilometer consisting of an atomic force microscope, and a first signal corresponding to the pattern to be inspected formed on the reticle mask is obtained. And the second signal obtained based on the design data when the reticle mask pattern is formed are compared to inspect the shape or the defect of the reticle mask, so that the measurement resolution is smaller than the minimum dimension handled by the design data. , Future 256M
Inspection of the shape or defect of the reticle mask after the bit can be easily achieved.

[0008]

The details of the present invention will be described below with reference to the illustrated embodiments.

FIG. 1A is a plan view showing a pattern according to design data, and FIG. 1B is a plan view showing an actual pattern to be inspected in which a defect exists, where 1 is a regular pattern. 2 indicates a white defect and 3 indicates a black defect.

FIG. 2 is a block diagram showing a schematic configuration of a reticle mask shape defect inspection apparatus according to the first embodiment of the present invention. Reference numeral 11 in the figure denotes a sample table on which the reticle mask 12 is placed, and the sample table 11 is controlled by the sample table drive control unit 14 instructed by the computer 13 so as to be in the X direction (left and right direction on the paper) and the Y direction (front and back direction on the paper). It is supposed to be moved to. The moving position of the sample table 11 is measured by the sample table position measuring unit 15 including, for example, a laser interferometer.

On the other hand, above the sample table 1, a stylus profilometer (detection unit) 16, specifically an atomic force microscope, is mounted on a housing supporting the stylus profilometer (detection unit) 16. ing.

Here, the atomic force microscope will be briefly described. The tip of a cantilever called a cantilever has a small tip with a sharp tip on the sample side.When the cantilever and the sample surface are brought close to each other, the atom between the tip of the tip and the atom on the sample surface An exchange repulsive force acts, and this force causes the cantilever with low rigidity to bend. When the probe and the sample are moved relative to each other in the in-plane direction, the bending of the cantilever changes according to the repulsive force distribution on the sample surface. Therefore, by reading the bend of the cantilever with the displacement detection mechanism, the shape of the sample surface can be known with high resolution. In practice, the two-dimensional microscopic shape of the sample surface is often examined by, for example, moving the sample up and down with an actuator so that the exchange repulsive force acting between the cantilever and the sample surface is always constant. A scanning tunneling microscope or a laser interferometer may be used as the displacement detection mechanism, but from the viewpoint of operability, a laser diode and a position sensitive detector (PS
An optical lever type detector using D) is often used. In this optical lever method, a laser beam is applied to the tip of the cantilever (however, the side opposite to the sample side), and the reflected light detects a positional change on the detector. The detection unit is a stylus profilometer 16, and a cantilever 31, a probe 32, a laser beam projector 33, a position sensitive detector (PSD) 34, etc. are housed in this unit. The detection unit 16 is vertically movable with respect to the reticle mask 12 by a drive mechanism 21 with a point 20 as a fulcrum.

The structure of the unit 16 will be described in detail with reference to FIG. The cantilever 31 is a cantilever having low rigidity (about 0.04 N / m), and the tip of the cantilever 31 has a small probe 32 having a sharp tip on the mask 12 side. As shown in FIG. 4, the shape of the cantilever 31 is V-shaped in order to increase the rigidity in the left-right direction and reduce the rigidity in the front-rear direction, and the dimensions of each part are as shown in the drawing. Cantilever 31
Is fixed to the fixed end 35, the fixed end 35 is movable in the horizontal direction with respect to the surface of the mask 12, and is fixed to the unit 16 by screwing or the like at a predetermined position. There is. A laser light projector 33 for irradiating the tip of the cantilever 31 with laser light is installed obliquely above the cantilever 31 so as to be able to advance and retreat in the projection direction of the laser light. The projector 33 includes a laser diode 33a and a focusing lens (or a lens group).
33b, the image forming position of the spot beam is changed by the movement in the light projecting direction. The reflected light from the carlent lever 31 due to the laser light irradiation is detected by the PSD 34.
Here, the projector 33, the cantilever 31, the PSD 34
Constitute an optical lever type detection mechanism. The actuator 21 drives the detection unit 16 in the vertical direction. For the actuator 21, for example, a combination of a laminated piezoelectric element 21a and a micrometer head 21b is used. With this actuator 21, the detection unit 16 causes the probe 32 at the tip of the cantilever 31 to the mask 12 with the support column 20 as a fulcrum. Is driven so that it is vertically displaced. Further, the tip of the support column that supports the detection unit 16 and a part of the housing that supports the detection unit 16 constitute, for example, a pivot bearing, and for example, one of them is formed by a magnet and both are fixed by magnetic force. It is supposed to be done. On the other hand, the strut of the detection unit 16 is only placed on the strut pedestal of the actuator 21, so that the actuator 2
Even if 1 is vertically displaced, the detection unit 16 does not largely shift in the horizontal direction with respect to the mask 12. With the detection unit 16 having such a configuration, the vertical measurement resolution 1
The cross-sectional shape of the light-shielding chrome film pattern on the reticle mask can be measured with a thickness of nm or less and a horizontal measurement resolution of 1 nm or less.

With such a stylus profilometer 16, the cross-sectional shape of the light-shielding chromium film pattern of the reticle mask 12 placed on the sample table 11 is measured. Here, the stylus profilometer 16 moves up and down when the reticle mask 12 moves in the X and Y directions so that the sample stage 11 can be continuously moved in a state where the stylus profilometer 16 can measure. The stage drive control unit 14 servo-drives the drive mechanism 21 in the vertical direction to follow the movement of the reticle mask so as to absorb a slight variation. In this state, the signal from the stylus profilometer 16 is sent to the signal detector 17, and the scanning signal (first scanning signal) corresponding to the pattern to be inspected of the reticle mask 12 is detected. Then, this detection signal is supplied to the defect determination section 19 together with the scanning signal (second scanning signal) generated based on the design data when the detection pattern is formed by the reference signal generation section 18. Has become.

As shown in FIG. 5, the defect determining section 19 includes a detection data buffer 22, a design data buffer 23, a first data converting circuit 24, a second data converting circuit 25, a difference signal generating circuit 26, a defect determining circuit 27, and a black system. Defect judgment buffer 2
8 and the white defect judging buffer 29, that is, the first scanning signal from the signal detecting section 17 is registered in the detection data buffer 22 and is sent to the differential signal generating circuit 26 via the first data converting circuit 24. Sent. Similarly, the second scanning signal from the reference signal generator 18 is registered in the design data buffer 23, and the second data conversion circuit 25
Is sent to the differential signal generation circuit 26 via. The difference signal generation circuit 26 detects the difference between the input scanning signals and the defect size of the pattern to be inspected, and the detected defect size is sent to the defect determination circuit 27. Defect determination circuit 27
Detects whether the detected defect is a black-based defect or a white-based defect based on whether the output signal of the difference signal generation circuit 26 is positive or negative, and based on the detection result, the black-based defect determination buffer 28 or the white-based defect determination buffer 29. The maximum allowable defect size registered in (1) and the detected defect size are compared and collated, and when the detected defect size is larger than the maximum allowable defect size, it is determined that there is a defect. The output signal of the defect determination circuit 27 is sent to the computer 13 as the determination information of the defect determination section 19. The allowable defect size registered in the black-based defect determination buffer 28 corresponds to the maximum size (threshold level) allowed for black-based defects, and the allowable defect size registered in the white-based defect determination buffer 29 is white. It corresponds to the maximum size (threshold level) allowed for defects.

With such a configuration, since the cross-sectional shape of the blocking chromium film pattern on the reticle mask is measured by the stylus profilometer 16, specifically, the atomic force microscope, the measurement resolution is the design data. The defect size is smaller than the minimum size to be handled, and the defect size obtained by comparing the first and second scanning signals by the difference signal generation circuit of the defect determination unit is used to inspect the shape or defect of the future reticle mask of 256 Mbits or later. It can be easily evaluated with the accuracy required for. With such a configuration, when the detected defect is the black defect shown in FIG. 1B, the maximum allowable defect size registered in the black defect determination buffer is compared with the detected defect size. It is determined that there is a defect only when the detected defect size is larger than the maximum allowable defect size. Similarly, when the detected defect is the white defect shown in FIG. 1B, the maximum allowable defect size registered in the white defect determination buffer is compared with the detected defect size,
It is determined that there is a defect only when the detected defect size is larger than the maximum allowable defect size. In other words, black defect and white defect
It will be compared to the corresponding maximum allowable defect size. Therefore, it becomes possible to perform the defect inspection accurately in the minimum necessary time. Therefore, the throughput of the defect inspection and the throughput in the repair process can be improved.

FIG. 6 is a view showing a partial detailed structure of a reticle mask shape defect inspection apparatus according to the second embodiment of the present invention, wherein (a) is a plane and (b) is a side view. The sample table 11 is moved in the X direction (left and right direction of the paper surface) and the Y direction (front and back direction of the paper surface) by the sample table drive control unit 14 which receives a command from the computer 13. The moving position of the sample table 11 is measured by the sample table position measuring unit 15 including, for example, a laser interferometer.
The reticle mask 12 is placed on the mask chuck table 41 on the sample table 11 via the scanning means 42. Scanning means 42
Moves the mask chuck base 41 in the X-axis direction with respect to the sample base 11. The scanning means 42 is supported by, for example, a parallel spring 43 so as to be movable only in the X-axis direction, and is driven by, for example, a laminated piezoelectric element 44 so as to be displaceable by 100 microns. With such a configuration, the sample table 11 on which the reticle mask 12 is placed is continuously moved in the Y direction, for example, and the reticle mask 12 on the mask chuck table 41 is 100 μm in a direction orthogonal to the sample table 11 using the laminated piezoelectric element 44. It can be moved back and forth. In the first embodiment, in order to inspect the entire surface of the reticle mask, the sample table 11 must be continuously reciprocated in the X-axis direction and must be step-moved in the Y-axis direction at the minimum measurement pitch, resulting in an extremely long measurement time. there were. On the other hand, in the second embodiment, since the reticle mask 12 is moved by using the piezoelectric element 44 for the width of 100 μm in the Y-axis direction, the measurement time required for moving the sample table 11 can be greatly reduced.

FIG. 7 is a diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to the third embodiment of the present invention. The block configuration is such that the distortion correction circuit 51 is added to the reticle mask shape defect inspection apparatus according to the first embodiment, and the sample table 11 is the sample table 11 with the reticle mask scanning means 42 shown in the second embodiment. It is used. In such a configuration, since the scanning of the reticle mask 12 in the Y direction is performed by the piezoelectric element 44, the hysteresis characteristic of the piezoelectric element 44 (the relationship between the applied voltage and the displacement is not linear) (FIG. 8) is obtained without correction. Distortion will occur in the measured data. Since the hysteresis characteristic can be measured in advance, it is sufficient to determine correction data from this data and use this to correct the measurement data. In the third embodiment, the distortion correction circuit 51 measures the measured data.
The piezoelectric element 44 of the scanning means is used for correction.
It is natural that the voltage applied in advance may be distorted by using a distorting circuit so that the hysteresis characteristic does not occur. In addition, although the correction is performed using a hardware circuit here, it is clear that the correction may be switched to a soft correction. It is also possible to distort the design data.

FIG. 9 is a diagram showing a partial detailed structure of a reticle mask shape defect inspection apparatus according to the fourth embodiment of the present invention. FIG. 9A is a plan view and FIG. 9B is a side view. In the first to third embodiments, the laser mirror 15 ′ used for measuring the position of the sample table 11 is attached to the side surface of the sample table 11. On the other hand, in the fourth embodiment, the laser mirror 15 'has the reticle mask 12
Is attached to the side surface of the reticle mask chuck base 42 for fixing the. With such a configuration, even when the scanning unit 42 having a hysteresis characteristic such as the piezoelectric element 44 is used, the position coordinates of the measurement point on the reticle mask 12 can be directly read, and thus the above-described distortion correction circuit is not provided. You will need it.

FIG. 10 is a diagram showing a partial detailed structure of the reticle mask shape defect inspection apparatus according to the fifth embodiment of the present invention, in which (a) is a perspective view and (b) is a partially cutaway view. In the first to fourth embodiments, the reticle mask 11 is moved with respect to the stylus profilometer 16 to measure the cross-sectional shape of the light-shielding chrome film pattern on the reticle mask 12, but in the present embodiment, the stylus profilometer is used. 16, that is, the cantilever 31 of the atomic force microscope is displaced for measurement. That is, the cantilever 31 is attached to the tip of the piezoelectric element 61 which can be displaced in, for example, three directions of X, Y, and Z. This piezoelectric element 61
The other end of the is fixed to the holder 62. The support column as in the first embodiment is attached to the holder 62, whereby the tip of the probe 32 of the cantilever 31 is attached to the sample table 1.
It is installed so as to face the reticle mask 12 above. On the other hand, the displacement of the cantilever 31 is detected by, for example, the piezoelectric thin film 63 attached on the cantilever 31. That is,
A thin film 63 made of a piezoelectric material such as ZnO is deposited on the cantilever 31. In this way, the thin film 63 generates a voltage according to the deformation of the cantilever 31.
By amplifying this voltage, a signal corresponding to the cross-sectional shape of the light-shielding chromium film pattern on the reticle mask 12 can be read. With such a configuration, the scanning range of the piezoelectric element 61 can be performed at a higher speed than that when the sample stage 11 is moved, so that the measurement can be performed at a higher speed than the above-described embodiment. The measurement at this time may be performed by scanning the cantilever while the sample table 11 is being raster-fed, or may be performed while the sample table 11 is step-and-repeat-fed. Further, the vertical movement of the reticle mask 12 due to the movement of the sample table 11 may be performed by using a drive mechanism 64 (comprising a piezoelectric element and a micrometer head) attached to the holder 62, or the Z direction of the thick electric element 61. The displacement may be used.

FIG. 11 is a diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to the sixth embodiment of the present invention. In the first to fifth embodiments, one stylus profilometer 16 measures the entire surface of the reticle mask 12. However, in this embodiment, a plurality of stylus profilometers 16 as shown in the first embodiment are used. The reticle masks 12 are arranged side by side and are measured in parallel. By doing so, the measurement time can be further reduced.

FIG. 12 is a diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to the seventh embodiment of the present invention. In the first to sixth embodiments described above, the entire surface of the reticle mask 12 is inspected by the stylus profilometer 16. However, it is often unnecessary to examine the entire surface of the reticle mask 12 with an atomic force microscope. The present embodiment is a reticle mask shape defect device relating to such a case. That is, this embodiment is the one in which the stylus profilometer 16 described above is added to the conventional reticle mask shape defect inspection apparatus. With such a configuration, the stylus profilometer 16 is used to measure only the problematic part when measured by the conventional method.
By doing so, the measurement can be performed more efficiently.

In the first to seventh embodiments, the apparatus for inspecting the shape defect of the pattern formed on the chromium film on the surface of the reticle mask has been described. However, the phase shift method is about to be adopted for reticle masks of 64M or later. That is, a phase shift film that can effectively use the phase information of light is formed on the chromium film formed on the mask surface, and the intensity distribution of light on the wafer is made sharper than in the case without the phase shift film. Is what you are trying to do. FIG. 13 shows cross-sectional structures of a normal mask and a phase shift mask. In the phase shift mask, a transparent film called a phase shifter is formed on an ordinary chrome film.
The phase shifters formed have different structures by different phase shift methods. With respect to the shifter edge type, the shape defect can be examined by using the device shown in the first to seventh embodiments. However, for the halftone type and the Levenson type, the shape defect of the chromium pattern cannot be examined by the measurement after the phase shifter is formed. Therefore, in order to inspect the shape defect of this type of phase shift mask, 2
You have to make one measurement.

FIG. 14 and FIG. 15 are views showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to the eighth embodiment for inspecting a phase shift mask. Since the basic structure is the same as that described in the first to seventh embodiments, only different points will be described here. That is, the essence of the present embodiment is that the reference point serving as the origin of the first measurement and the second measurement is provided in the phase shift mask, and the first and second
In the above measurement, the stage position measuring unit can be reset at this reference point, and the comparison circuit for the first and second measurement results is provided. 81 in the figure is a reference point, 82
Is a reset circuit, 83 is a measurement result buffer, and 84 is a comparison circuit. The reference point 81 on the phase shift mask 12 is detected by the detection unit 16 and the signal detection unit 17, and the stage position measurement unit 15 is reset by the reset circuit 82 at the detected position coordinates. This operation may be managed by the computer 13. The measurement is performed and the first measurement is performed. The defect inspection is performed in the same manner as the normal mask to determine the quality of the mask. At this time, the measurement result is held in the measurement result buffer 83. A mask that has passed the mask inspection is subjected to a predetermined manufacturing process to form a phase shifter. The inspection of this phase shifter is performed in the same manner as the first measurement. The quality of the phase shifter is inspected and sent to the measurement result buffer 83, where it is compared and inspected by the comparison circuit 84 with the first measurement result. This completes the shape defect inspection of the phase shift mask. With such a configuration, shape defect inspection can be performed even with a reticle mask having a laminated structure such as a phase shift mask.

In the first to eighth embodiments, the apparatus for inspecting the shape defect of the pattern formed on the chromium film on the surface of the reticle mask has been described. However, an X-ray mask is about to be adopted for pattern formation after 1 GM (minimum line width: 0.15 μm or less).
That is, an attempt is made to form a pattern by forming an X-ray absorber on the surface of a mask, exposing the X-ray on the wafer with an intensity distribution, and performing resist exposure. FIG. 16 shows a sectional structure of the X-ray mask. The X-ray mask has a larger aspect ratio than the reticle mask and the phase shift mask. This is because the film thickness is at least 0.5 μm or more to absorb X-rays and the X-ray exposure is 1: 1 transfer. Therefore, even in the apparatus of the first to eighth embodiments in which the probe can scan the surface of a normal chromium film having a small aspect ratio, the probe has a finite size in the X-ray mask having a large aspect ratio. Since it has, the probe cannot enter the groove with a narrow frontage and its shape cannot be measured.

FIG. 17 is a diagram showing the partial detailed structure of a reticle mask for inspecting an X-ray mask, particularly a shape defect inspection apparatus for an X-ray mask. Since the basic configuration is the same as that described in the first to eighth embodiments, only the different signal detection unit 17 will be described here. That is, the essence of the present embodiment is that the shape of the mask pattern is determined using the edge information of the pattern cross-sectional profile. In the figure, 91 is an X-ray mask 90.
3 is an example of cross-sectional profile information of a pattern obtained when the inspection is performed. In an ordinary inspection of a reticle mask, since the chromium film has a small aspect ratio, the tip of the probe is scanned along the surface of the ratio inspection pattern, so that the measurement profile is detected without distortion. Therefore, if the measurement profile is cut with an arbitrary threshold setting value, the shape of the chrome pattern and the contour of the defect can be obtained. On the other hand, in the measurement of the X-ray mask, the cantilever probe 32 has a large aspect ratio and does not reach the bottom of the groove, so that the profile becomes distorted as compared with the normal measurement.
However, as can be seen from the figure, since the profile curve changes extremely sharply at the edge position, the edge position 92
Can be measured. That is, when the profile curve is differentiated by the differentiating circuit 93, a differential curve 94 having an extremely steep slope at the edge position is obtained. The absolute value of the differential curve 94 is obtained by the absolute value circuit 95, and the detection curve 96 is output. The threshold setting circuit 97 sets the area that is equal to or more than the set value to zero to obtain the image signal 98, which is represented by, for example, a grayscale image. And the shape of the pattern can be observed. The position of the defect or the shape abnormality of the X-ray mask thus performed is stored by the stage position measuring unit. This device cannot accurately measure the cross-sectional profile, so abnormalities inside the groove cannot be detected. However, at present, even with an inspection device that uses an electron beam, sufficient measurement inside the groove is not possible, so the shape for primary evaluation of the X-ray mask It is extremely effective as a defect inspection device.

FIG. 18 is a diagram showing a partial detailed structure of a reticle mask for inspecting an X-ray mask, in particular, a shape defect inspection apparatus for an X-ray mask. Since the basic structure is the same as that described in the first to eighth embodiments, only different points will be described here. That is, the essence of the present embodiment is characterized in that the probe of the cantilever for inspecting the shape of the mask pattern is shaped so that it can enter even the bottom of the pattern having a large aspect ratio. A columnar probe 99 using the electron beam deposition method is formed at the tip of the cantilever probe 32. This forming method is described in detail in the patent application specification of application number P01-067090. According to this method, a probe having a thickness of 1000 angstroms or less and a height of 4 microns or more can be formed, so that the shape defect inside the groove having a large aspect ratio can be inspected. In the figure, 100 is an electron beam,
101 indicates a gas molecule.

[0028]

As described in detail above, according to the present invention, the cross-sectional shape of the light-shielding chromium film pattern on the reticle mask is determined by a stylus profilometer consisting of an atomic force microscope, and the inspection object formed on the reticle mask is inspected. Since the first signal corresponding to the pattern and the second signal obtained based on the design data when forming the reticle mask pattern are compared to inspect the shape or the defect of the reticle mask, the measurement resolution is designed. The size of the reticle mask is smaller than the minimum size handled by the data, and future inspection of the shape or defect of the reticle mask of 256 Mbits or later can be easily achieved.

[Brief description of drawings]

FIG. 1 is a plan view showing a pattern (a) corresponding to design data and an inspected pattern (b) having various defects on a reticle mask.

FIG. 2 is a schematic configuration block diagram of a reticle mask shape defect inspection apparatus according to the first embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view for explaining the principle and configuration of an atomic force microscope.

FIG. 4 is a plan view showing a specific structure of a cantilever.

FIG. 5 is a block diagram showing a detailed configuration of a defect determination unit.

FIG. 6 is an external view showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a second embodiment of the present invention.

FIG. 7 is a block diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a third embodiment of the present invention.

FIG. 8 is a diagram for explaining the correction effect of the hysteresis characteristic of the piezoelectric element.

FIG. 9 is an external view showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a fourth embodiment of the present invention.

FIG. 10 is an external view showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a fifth embodiment of the present invention.

FIG. 11 is a diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a sixth embodiment of the present invention.

FIG. 12 is a block diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a seventh embodiment of the present invention.

FIG. 13 is a principle diagram for explaining a configuration of a phase shift mask.

FIG. 14 is a block diagram showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a seventh embodiment of the present invention.

15 is a block diagram showing details of main parts of the apparatus shown in FIG.

FIG. 16 is a structural diagram for explaining the configuration of an X-ray mask.

FIG. 17 is a waveform diagram showing a partial detailed configuration of the reticle mask shape defect inspection apparatus according to the eighth embodiment of the present invention.

FIG. 18 is a partial enlarged view showing a partial detailed configuration of a reticle mask shape defect inspection apparatus according to a ninth embodiment of the present invention.

[Explanation of symbols]

 1 ... Regular pattern 2 ... White defect 3 ... Black defect 11 ... Sample stage 12 ... Reticle mask 13 ... Calculator 14 ... Stage drive control unit 15 ... Stage position measuring unit 15 '... Laser mirror 16 ... Detection unit 17 ... Signal detection Part 18 ... Reference signal generating part 19 ... Defect determining part 20 ... Support point 21 ... Detection unit vertical drive mechanism 22 ... Detection data buffer 23 ... Design data buffer 24 ... First data conversion circuit 25 ... Second data conversion circuit 26 ... Difference Signal generation circuit 27 ... Defect determination circuit 28 ... Black defect determination buffer 29 ... White defect determination buffer 31 ... Cantilever 32 ... Probe 33 ... Laser light projector 34 ... Position sensitive detector 35 ... Fixed end 41 ... Scanning procedure 42 ... Mask Chuck table 43 ... Parallel spring 44 ... Piezoelectric element 51 ... Strain correction circuit 61 ... Three-dimensional piezoelectric element 62 ... Piezoelectric element holder 63 ... Piezoelectric thin film 64 ... Piezoelectric element holder vertical drive mechanism 71 ... Light source 81 ... Reference point 82 ... Reset circuit 83 ... Measurement result buffer 84 ... Comparison circuit 90 ... X-ray mask 91 ... Obtained during X-ray mask measurement Detection signal 92 ... Edge position 93 ... Differentiation circuit 94 ... Differential curve 95 ... Absolute value circuit 96 ... Absolute value curve 97 ... Threshold setting circuit 98 ... Image signal 99 ... EBD columnar probe

Claims (4)

[Claims] 1. A reticle mask of a reticle mask is compared by comparing a first signal corresponding to a pattern to be inspected formed on a reticle mask with a second signal obtained based on design data for forming a reticle mask pattern. An apparatus for inspecting a shape or a defect, wherein a first signal corresponding to the pattern to be inspected is obtained by using a stylus profilometer. A reticle mask shape defect inspection device characterized by performing a raster scan of a stylus profilometer while performing raster movement or step-and-repeat movement of the prepared sample stage to inspect the shape or defect of the reticle mask. 2. A reticle mask of a reticle mask is compared by comparing a first signal corresponding to a pattern to be inspected formed on a reticle mask with a second signal obtained based on design data when forming a reticle mask pattern. An apparatus for inspecting a shape or a defect, wherein a reticle mask shape defect inspection apparatus is characterized in that a first signal corresponding to the pattern to be inspected is obtained by using a stylus profilometer. A light irradiation unit for irradiation, a first signal corresponding to the pattern to be inspected formed on the reticle mask obtained by irradiation of the light and movement of the light irradiation position on the reticle mask, and a reticle mask pattern are formed. Reticle mask shape defect detection for inspecting the shape or defect of the reticle mask by comparing with a second signal obtained based on the design data at the time. A reticle mask shape defect inspection device characterized by being incorporated in an inspection device. 3. A reticle mask of a reticle mask is compared by comparing a first signal corresponding to an inspection pattern formed on a reticle mask with a second signal obtained based on design data when forming a reticle mask pattern. An apparatus for inspecting a shape or a defect, wherein a reticle mask shape defect inspection apparatus is characterized in that a first signal corresponding to the inspected pattern is obtained by using a stylus profilometer. When inspecting a reticle mask composed of a plurality of thin film bodies, a reference point for each thin film body is provided on the reticle mask, and when measuring each thin film body, the stage position measuring unit is reset by the position coordinates of the reference point. The feature is that it is configured so that the shape defects can be inspected for each thin film body and the inspection results between multiple thin film bodies can be compared. Reticle mask shape defect inspection device. 4. A reticle mask of a reticle mask is compared by comparing a first signal corresponding to a pattern to be inspected formed on a reticle mask with a second signal obtained based on design data when forming a reticle mask pattern. A device for inspecting a shape or a defect, wherein a reticle mask shape defect inspection device is characterized in that a first signal corresponding to the inspected pattern is obtained by using a stylus profilometer. The defect shape inspection of a pattern having a large aspect ratio such as an X-ray mask is performed by obtaining the contour of the pattern to be inspected by using the signal corresponding to the edge of the pattern to be inspected in the measured profile curve. Reticle mask shape defect inspection device.