JPH10206500A - Calibration sample, probe position correcting apparatus using the calibration sample, fine wiring inspecting apparatus and probe position correcting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure a shift in position when a probe to be in contact with a fine wire has been replaced in a short time. SOLUTION: The calibration sample comprises position detection blocks PO to P7 for detecting an X-direction position and position detection blocks Q0 to Q7 for detecting a Y-direction position. The position detection blocks P0 to P7 for detecting the X-direction position are formed with position identification patterns of respectively different uneven shapes on a surface. In addition, the position detection blocks Q0 to Q7 for detecting the Y-direction position are similarly formed with position identification patterns of respectively different uneven shapes. Therefore after a probe is brought into contact with any one of the blocks P0 to P7 for detecting the X-direction position, the probe can be brought into contact with any one of the blocks Q0 to Q7 for detecting the Y-direction position. Thus the calibration sample can be used to correct both a shift in the center of a field of view of an optic microscope and a shift of the probe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calibration sample suitable for correcting a scanning position of a probe for inspecting fine wiring of a sample to be measured such as a semiconductor chip, and a probe position correcting apparatus using the calibration sample. And a fine wiring inspection apparatus and a probe position correction method.

In developing and manufacturing a semiconductor integrated circuit, if there is an operation failure by testing a semiconductor chip, it is essential to investigate the cause. However, recent LSI
As a result, it is becoming difficult to perform accurate design verification and failure analysis only by a method of measuring a signal of an I / O pin of an LSI tester or the like.

[0005] For this reason, an operation test of a semiconductor integrated circuit is performed using a fine wiring inspection apparatus for measuring a voltage of a fine wiring formed on a semiconductor chip. As the fine wiring inspection apparatus, for example, an apparatus using an electron beam is known. However, as the integration and speed of semiconductor integrated circuits increase, measurement speed and time resolution are becoming insufficient.

Accordingly, a fine wiring inspection apparatus has been developed which utilizes a technique of an atomic force microscope to search for wiring using a conductive fine probe (probe) and measure the voltage with a high spatial resolution using a light beam having a function of positioning the probe. Have been. In the fine wiring inspection apparatus using the conductive fine probe, since the scanning position varies depending on the mounting state of the conductive fine probe, in order to secure the inspection accuracy, the position of the conductive fine probe must be accurately detected. It is necessary to perform position correction.

[0005]

2. Description of the Related Art As a conventional fine wiring inspection apparatus, for example, as disclosed in Japanese Patent Application Laid-Open No. Hei 7-244054 previously proposed by the present applicant, an optical microscope for observing a sample and a scanning probe microscope are used. Combined configurations have been developed. Scanning probe microscopes convert the interaction (for example, atomic force) between materials into displacement with a small cantilever and a probe, detect it with displacement detection means such as laser light, and produce a fine three-dimensional surface of the sample. To get the shape.

After searching for the observation position with an optical microscope, the observation is switched to a scanning probe microscope. In this switching operation, the optical microscope and the scanning probe microscope are mounted on the same stage, and the stage is moved to move the scanning probe microscope to a sample (object to be observed) observed by the optical microscope.

As a probe for detecting the voltage of a fine wiring, for example, Japanese Patent Application Laid-Open No. 7-146 proposed by the present applicant has been proposed.
There is one disclosed in Japanese Patent Publication No. 316. In this publication, a hollow rod supporting a probe is supported by two leaf springs and is vertically displaceable, and the amount of displacement is determined by a movable electrode and a fixed electrode attached to the hollow rod. The detection is performed using the fact that the capacitance changes due to the change in the gap between.

That is, when the probe is pressed with a small force on the wiring, the leaf spring causes a bending displacement. When the displacement is detected, the pressing force between the probe and the wiring can be detected.
As shown in FIG. 15, the hollow rod 1 is hollow so that a laser beam can pass therethrough, and a voltage information generating element including a transparent electrode 2, an electro-optic crystal 3, and a reflection film 4 at the tip of the hollow rod 1. Is arranged. The voltage of the wiring with which the tip of the probe contacts the conductive probe 5 is transmitted to the voltage information generating element (in particular, the electro-optic crystal 3). When the laser light is passed through the electro-optic crystal 3, the polarization of the laser light changes due to the electric field between the transparent electrode and the reflective film of the electro-optic crystal 3, and the voltage is measured by detecting the amount of this polarization.

The tip of the probe is very sharp (less than 1 μm)
Therefore, when the tip of the probe 5 is brought into contact with the fine wiring on the surface of the sample, the tip of the probe 5 wears as the number of uses increases. Therefore, when the tip of the probe 5 is worn, it is necessary to replace the probe 5 with a new one.

In the above publication, the permanent magnet 6 is attached to the lower surface of the reflection film 4, the magnetic material 7 is fixed to the upper end of the probe 5, and the needle can be replaced using magnetic attraction.

[0011]

However, in the conventional apparatus as described above, the position of the probe 5 may be shifted when the probe 5 is replaced by utilizing magnetic attraction. For example, FIG.
As shown in FIG. 6, the magnetic material 7 adsorbed by the magnet 6 is adsorbed at a position shifted by d ₁ at the root of the probe 5 or the probe 5 itself is inclined to the mounting surface of the magnetic material 7 to be probed. When the tip of the needle 5 is attached at a position shifted by d ₂ from the axis,
An error occurs in the mounting position of the probe 5.

Therefore, after replacing the probe 5, the probe 5
It is necessary to measure the position of the tip of the probe and correct the error due to the probe replacement. However, in the fine wiring inspection apparatus, the stage for supporting the probe is set in a relatively narrow range (10
A fine-movement drive unit that precisely positions the microscope (0 μm or less) and a coarse-movement drive unit that roughly positions the microscope and the stage supporting the probe over a relatively wide range (several tens of mm or more). Are provided.

In order to measure the position of the probe 5, a method is used in which the tip of the replaced probe 5 is brought into contact with a calibration sample. FIG. 17A shows a conventional calibration sample used in a fine wiring inspection apparatus. On the upper surface of the calibration sample 8, a pattern 8a protruding in a square shape when viewed from above is formed. Therefore, when the tip of the probe 5 moves horizontally in the X direction and rides on the edge of the pattern 8a of the calibration sample 8, FIG.
7B is output, and when the tip of the probe 5 moves horizontally in the Y direction and rides on the edge of the pattern 8a, a signal as shown in FIG. 17C is output. The tip position of the probe 5 can be measured from the rising position of this signal.

When measuring the position of the probe 5 which has been replaced, the optical microscope and the calibration sample 8 are aligned, and then the probe 5 and the calibration sample 8 are aligned. When the probe 5 is replaced, first, the calibration sample 8 is observed with an optical microscope by the coarse movement driving unit, and the edge position of the calibration sample 8 in the XY directions is obtained.

Next, the stage is switched to position the tip of the probe 5 at an approximate position observed by an optical microscope by the coarse driving unit, and thereafter, the probe 5 is scanned by the fine driving unit to calibrate the calibration sample. 8 is observed, and the pattern 5 of the calibration sample 8 is observed by the probe 5.
An edge position in the XY direction of a is obtained.

The relative position between the center of the field of view of the optical microscope and the probe 5 is measured from the results of both observations with the optical microscope and the probe 5. However, when the calibration sample 8 and the probe 5 are aligned with each other, a positional deviation d ₁ of the root of the probe 5 due to magnetic attraction or a variation in manufacturing of the probe 5 (a positional deviation between the probe 5 and the magnetic material 7, Or the displacement d ₂ due to the inclination of the probe 5)
As a result, the operation range of the fine movement drive unit may be exceeded. In this case, there is a problem that the target (the edge of the pattern 8a of the calibration sample 8) observed by the optical microscope cannot be observed even when the probe 5 is scanned, and the alignment cannot be performed.

Therefore, if the displacement of the probe 5 is within the operating range of the fine movement driving unit, the position of the probe 5 can be measured in a relatively short time. If it is out of the range, the probe 5 is moved by the coarse drive unit to the calibration sample 8.
Therefore, it is necessary to drive the coarse movement drive section and then drive the fine movement drive section as described above, which requires a considerable amount of time.

The present invention has been made in view of the above points, and has a calibration sample for measuring the position of a probe by contact with the probe, a probe position correcting device using the calibration sample, and a fine wiring inspection device. And a method for correcting a probe position.

[0019]

Means for Solving the Problems In order to solve the above problems, the present invention is characterized by taking the following various means. The invention according to claim 1 has a plurality of position detection blocks in which different position identification patterns due to unevenness extending in one direction are individually formed on a surface with which the probe contacts, and the position detection pattern is formed based on a combination of the position identification patterns. The scanning position of the probe is detected.

Further, the invention according to claim 2 is a calibration sample having a plurality of position detection blocks in which different position identification patterns formed by unevenness extending in one direction on the surface with which the probe contacts are individually formed, Scanning position information generation for detecting a position identification pattern by sliding a needle into one position detection block formed on the surface of the calibration sample and generating coded scanning position information from a combination of the position identification patterns Unit, a probe position detecting unit that calculates a coordinate position where the probe is in contact from the scanning position information generated by the scanning position information generating unit, and a coordinate position detected by the probe position detecting unit. And a correction operation unit for correcting the scanning position of the probe based on the correction operation.

According to a third aspect of the present invention, a fine wiring formed on a sample to be measured is imaged by an imaging unit, and a probe is attached to the fine wiring of the sample to be measured based on image information captured by the imaging unit. In a fine wiring inspection apparatus that drives a fine movement driving section and a coarse movement driving section so as to make contact with each other and inspects fine wiring of the sample to be measured, each side is formed to have a size smaller than an operation range of the fine movement driving section. A calibration sample having a plurality of position detection blocks in which different position identification patterns formed by unevenness extending in one direction on the surface with which the probe is brought into contact are formed, and the probe is formed on the surface of the calibration sample. Scanning position information generating the scanning position information by detecting the position identification pattern in sliding contact with another position detection block and generating coded scanning position information from a combination of the position identification patterns. A probe position detection unit that calculates a coordinate position where the probe is in contact from the scanning position information generated by the scanning position information generation unit, and a coordinate position detected by the probe position detection unit. And a correction operation unit for correcting the scanning position of the probe.

According to a fourth aspect of the present invention, a position identification pattern is formed on the surface of the calibration sample with which the probe comes in contact with the unevenness extending in one direction, and the probe is slid into contact with the unevenness to form the position identification pattern. A probe position correction method comprising: detecting an identification pattern; and correcting a scanning position of the probe contacted with the calibration sample from a combination of the position identification pattern.

According to a fifth aspect of the present invention, the position identification pattern is detected by bringing a probe into sliding contact with the position identification pattern formed on the surface of the calibration sample. Generating the calculated scanning position information, calculating the coordinate position at which the probe is in contact with the scanning position information, and correcting the scanning position of the probe based on the calculated coordinate position. This is a probe position correction method.

Each of the above means operates as follows. According to the first aspect of the present invention, the probe is brought into contact with the surface of a calibration sample having a plurality of position detection blocks in which different position identification patterns formed by unevenness extending in one direction are individually formed. Since the scanning position of the probe is detected from the combination of the above, the position of the probe can be easily measured, and the time required to detect the position of the probe can be reduced.

According to the second aspect of the present invention, in the probe position correcting device, the position identification pattern is detected when the probe comes into sliding contact with one position detection block formed on the surface of the calibration sample to detect the position identification pattern. To generate coded scanning position information from a combination of patterns, calculate the coordinate position where the probe is in contact from the scanning position information, and correct the scanning position of the probe based on the detected coordinate position. In addition, the time required for detecting the position of the probe can be reduced, and the scanning position of the probe can be accurately corrected.

According to the third aspect of the present invention, in the fine wiring inspection apparatus, each side of the calibration sample is formed to have a size smaller than the operation range of the fine movement driving unit, and the probe is formed on the surface of the calibration sample. The position identification block is slid into contact with the other position detection block to detect the position identification pattern, generate coded scanning position information from the combination of the position identification pattern, and calculate the coordinate position where the probe touched from the scanning position information. To correct the scanning position of the probe based on the detected coordinate position, thereby shortening the time required to detect the position of the probe,
The scanning position of the probe can be accurately corrected.

According to the fourth aspect of the present invention, a position identification pattern is formed on the surface of the calibration sample with which the probe comes into contact with the unevenness extending in one direction, and the probe is brought into sliding contact with the unevenness to identify the position. A probe position correction method that detects a pattern and corrects the scanning position of the probe that has come into contact with the calibration sample from the combination of the position identification patterns can shorten the time required to detect the position of the probe, and Can be accurately corrected.

According to the fifth aspect of the present invention, the position identification pattern is detected by sliding the probe into contact with the position identification pattern formed on the surface of the calibration sample. Generating the calculated scanning position information, calculating a coordinate position where the probe is in contact with the scanning position information, and correcting the scanning position of the probe based on the calculated coordinate position. The probe position correction method can shorten the time required to detect the position of the probe, and can correct the scanning position of the probe accurately.

[0029]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing a configuration of an embodiment of a fine wiring inspection apparatus using a calibration sample according to the present invention. First, the configuration and operation of the fine wiring inspection apparatus of the present invention will be described, and then the shape of the calibration sample of the present invention will be described.

A measurement sample 12 (for example, an LSI) is mounted on a base 11 supported by a vibration isolator of the fine wiring inspection apparatus. Y-axis direction guide rails 16 extending in the Y direction are attached to both ends of the base 11. On the guide rails 16, blocks 18 a of the Y-axis direction table 18 are movably provided. The table 18 is moved in the Y-axis direction by a Y-axis direction drive motor (not shown) provided on the base 11.

An X-axis direction guide rail 20 extending in the X-axis direction is attached to the Y-axis direction table 18.
The X-axis direction guide rail 20 has an X-axis direction table 2
2 is movably mounted. The X-axis direction table 22 is moved in the X-axis direction by driving a ball screw 28 by an X-axis direction drive motor 24 provided on the Y-axis direction table 18.

The X-axis direction table 22 is provided with a Z-axis direction guide rail 32 extending in the Z-axis direction. A focus adjustment stage 34 is movably attached to the Z-axis direction guide rail 32. The focus adjustment stage 34 is moved in the Z-axis direction by driving a ball screw 38 by a Z-axis direction drive motor 36 provided on the X-axis direction table 22.

The X-axis direction table 22, X-axis direction guide rail 20, X-axis direction drive motor 24, ball screw 2
8, a Y-axis direction table 18, a Y-axis direction drive motor (not shown), a Y-axis direction guide rail 16, a Z-axis direction guide rail 32, a Z-axis direction drive motor 36, and a ball screw 38. , Y and Z directions.

An optical microscope 40 is provided on the focus adjustment stage 34, and an image pickup unit 40a composed of a CCD image sensor is mounted above the optical microscope 40. The focus adjustment stage 34 includes
A scanning probe microscope 46 is provided. The scanning probe microscope 46 includes a moving stage 48 for performing scanning in the X-axis direction, the Y-axis direction, and the Z-axis direction,
An actuator unit 49 having an actuator in each direction composed of a piezo element for slightly displacing the probe 50 in the X-axis direction, the Y-axis direction, and the Z-axis direction;
And a displacement sensor 52 for detecting the amount of displacement in the axial direction.

The probe 50 is connected to the moving stage 4 as described later.
The probe 8 is held by a probe holder 51 attached to a lower end of the probe 8. The movement stage 48 and the actuator unit 49 constitute a fine movement driving unit 53 for finely moving the probe 50. In the fine movement driving section 53 of the present embodiment,
The probe 50 can be moved with a stroke of 60 μm.

As described above, the focus adjustment stage 34 includes
An optical microscope 40 and a scanning probe microscope 46 are attached. Then, the X-axis direction table 22 is moved in the X-axis direction by the ball screw 28, and the probe 50 of the optical microscope 40 or the scanning probe microscope 46 is moved to the measurement sample 12.
Is matched to

Here, the operation and operation of the fine wiring inspection apparatus configured as described above will be described. First, when observing the measurement sample 12 using the optical microscope 40, the ball screw 28 is driven by the
The axial direction table 22 is moved leftward in FIG.
By stopping at an appropriate position, the state shown in FIG. 1 is obtained.

Thereafter, the Z axis direction drive motor 36 drives the ball screw 38 to move the focus adjustment stage 34 in the Z axis direction, so that the focus of the optical microscope 40 provided on the focus adjustment stage 34 is adjusted. Thus, the optical microscope 40 can be moved to a position where the measurement sample 12 is desired to be observed.

As described above, the visual field of the optical microscope 40 is moved to a position where the observation of the measurement sample 12 is desired to be observed, and the observation is performed by the optical microscope 40, and then the observation is switched to the observation by the scanning probe microscope 46. Hereinafter, this point will be described. By driving the ball screw 28 by the X-axis direction drive motor 24 of the coarse movement drive unit 39 to move the X-axis direction table 22 rightward in FIG. 1 and stopping at an appropriate position, the scanning probe microscope 46 The probe 50 is arranged on a position of the measurement sample 12 to be observed as shown in FIG.

Thereafter, the Z-axis direction drive motor 36 is driven to lower the focus adjustment stage 34, and the probe 50 of the scanning probe microscope 46 is lowered to the observation position of the measurement sample 12 to start observation. The observation of the measurement sample 12 by the scanning probe microscope 46 is performed by scanning the surface of the measurement sample 12 while the position of the probe 50 is finely adjusted by the actuator unit 49 of the fine movement drive unit 53 in the X-axis direction and the Y-axis direction. Done.

A case will be described in which the displacement of the probe 50 with respect to the measurement sample 12 is detected and corrected using a calibration sample 100 described later. Base 11 of fine wiring inspection equipment
, A calibration sample 100 and a measurement sample 12 are mounted.

On the base 11, a spare probe 50 is provided.
Is provided. After the probe 50 is replaced, the optical microscope 40 and the calibration sample 10 are replaced.
Align with 0. That is, the optical microscope 40 is moved in the X and Y directions so that the center of the visual field of the optical microscope 40 is aligned with the vicinity of the end point G0 (see FIG. 5) of the calibration sample 100.

FIG. 3 shows a probe holder 51 for holding the probe 50.
FIG. 3 is an enlarged longitudinal sectional view showing the configuration of FIG. Probe holder 51
Is configured so that when the probe 50 is displaced upward by contact with the fine wiring of the measurement sample 12, the displacement is detected and the voltage of the fine wiring is detected.
Are rotationally symmetric about the axis, except for. Cross beam 6
0,62 has a plane of symmetry passing through this axis.

The cross beams 60 and 62 are formed in a cross shape when viewed from above, and the outer ends are cylindrical holders 70.
And the inner end is fixed to the outer peripheral surface of the hollow rod 72 that supports the probe 50. In addition, cross beam 6
A movable-side conductive plate 64 fixed vertically to the outer peripheral surface of the hollow rod 72 is provided between 0 and 62. An upper conductive plate 66 fixed to the inner surface of the holder 70 is provided above the conductive plate 64 so as to face the lower conductive plate 68 fixed to the inner surface of the holder 70 below the conductive plate 64. It is provided. Therefore, the conductive plate 64 is located between the upper conductive plate 66 and the lower conductive plate 68 on the fixed side, and is mounted so as to be displaceable in the axial direction (vertical direction) together with the hollow rod 72.

When the hollow rod 72 moves in the axial direction, the conductive plate 64 approaches one of the upper conductive plate 66 and the lower conductive plate 68 and separates from the other. 68 changes.
Thereby, the axial displacement of the probe 50 and the hollow rod 72 can be detected.

The conductive plates 64, 66, and 68 are connected to a capacitance detection circuit including a well-known Wheatstone bridge circuit via lead wires (not shown).
At the lower end of the hollow rod 72, a voltage information generating element 8 including a transparent electrode 74, an electro-optical crystal 76, and a reflection film 78 is provided.
0 is attached. Then, the voltage information generating element 8
To 0, the voltage of the fine wiring contacted with the probe 50 is applied. Further, a permanent magnet 82 for magnetically attracting the probe 50 is fixed to the lower surface of the reflection film 78.

A disc-shaped magnetic material 84 is fixed to the upper end of the probe 50. Therefore, when attaching the probe 50, the magnetic material 84 integrated with the probe 50 is attracted to the permanent magnet 82. The laser light applied to the inside of the hollow rod 72 passes through the transparent electrode 74 of the voltage information generating element 80 and the electro-optic crystal 76 and is reflected by the reflection film 78. Then, in the electro-optic crystal 76, a phase difference is given between the linearly polarized light components whose electric vector oscillation directions are perpendicular to each other in the electro-optic crystal 76 according to the voltage of the fine wiring applied through the probe 50. The reflected light from the voltage information generating element 80 is detected by a photodetector (not shown) via a polarizing beam splitter (not shown), and the potential of the fine wiring is measured based on the detected light.

FIG. 4 is a block diagram of a probe position correcting device 90 for detecting a position shift of the probe 50 and performing a probe position correction operation. The control device 92 of the probe position correcting device 90 drives and controls the drive motors in the respective directions of the coarse drive unit 39 and the actuators of the fine drive unit 53 for detecting the probe position when the probe is replaced. Further, the control device 92 controls the conductive plate 64, which is obtained by scanning the probe 50
Capacitance detection circuit 9 for detecting capacitance between 66 and 68
4 is connected.

The capacitance detection circuit 94 outputs a signal of a waveform corresponding to the unevenness of the position identification pattern of each position detection block formed on the surface of the calibration sample to the control device 92. The control device 92 codes the signal output from the capacitance detection circuit 94 and detects the tip position (coordinate position) of the probe 50 based on the coded position information.

Then, the control device 92 generates probe position correction data from positional deviation data (coordinate data such as the amount and direction of deviation) from the detected tip end position of the probe 50 to the regular probe mounting position. Output from the position correction data output unit 96. The memory (ROM) of the control device 92
A position detection pattern is detected by sliding the probe 50 in contact with one position detection block formed on the surface of the calibration sample,
A scanning position information generation program that generates coded scanning position information from a combination of the position identification patterns; a probe position detection program that calculates a coordinate position where the probe 50 is in contact from the scanning position information; A correction calculation program for correcting the scanning position of the probe 50 based on the coordinate position is stored.

Here, the shape of the calibration sample according to the present invention will be described. FIG. 5 is a plan view showing the shape of the calibration sample of the present invention, and FIG. 6 is an enlarged plan view showing a position detection block of the calibration sample. The calibration sample 100 according to the present embodiment includes position detection blocks P0 to P7 for X-direction position detection and position detection blocks Q0 to Q7 for Y-direction position detection. The corner on the left side of the calibration sample 100 is an end point G0 at which the center of the visual field of the optical microscope 40 is aligned when the optical microscope 40 is aligned.

The X direction position detection blocks P0 to P7 have eight blocks arranged in a line in the X direction, and the Y direction position detection blocks Q0 to Q7 are X direction position detection blocks P0 to P7.
Eight blocks are arranged adjacent to 0 to P7 and arranged in a line in the Y direction. Each X direction position detection block P0
As for P7, a position identification pattern having a different uneven shape is formed on the surface. Similarly, the Y-direction position detection blocks Q0 to Q7 are also formed with different position identification patterns having uneven shapes. Therefore, after detecting the position in the X direction by bringing the probe 50 into contact with any of the X direction position detection blocks P0 to P7, the probe 50 is moved to the Y direction position detection block Q.
The position in the Y direction can be detected by touching any one of 0 to Q7.

FIG. 6 shows X-direction position detection blocks P0 to P2.
6 is an enlarged plan view showing an example of the position identification pattern formed in FIG. 7, and FIG. 7 is a longitudinal sectional view taken along line AA 'in FIG.
In each of the blocks P0 to P7, a boundary portion 101 indicating a block boundary and code portions 102 to 104... Indicating position information of the blocks P0 to P7 are formed. In FIG. 6, a boundary portion 101 between blocks P0 to P2 is shown.
And only the code portions 102 to 104 are shown in an enlarged manner, but the other blocks P3 to P7 are similarly formed with the boundary portion 101 and the code portion arranged side by side.

The boundary portion 101 is formed by the concave portion 101a and the convex portion 10a.
1b, and the recess 101a is formed so as to be in contact with an adjacent block. The concave portion 101a has a width L1 = 4
μm, and the width of the convex portion 101b is set to 12 μm. The code portions 102 to 111 of each of the blocks P0 to P7 are composed of a combination of three irregularities.
It is formed to indicate bit position information. Each bit of the code portions 102 to 111 has a width L3 = 8 μm and a concave portion 102a which is entirely concave, or a width L4 = 4 μm
Of the projection 102b having a width L5 = 4 μm. Accordingly, the width of each bit is 8 μm, and the width of each of the code sections 102 to 111 is 24 μm.

For example, the code section 102 of the block P0
Has three recesses 102a formed continuously. Further, the code portion 103 of the block P1 includes a concave portion 102b,
It comprises a convex part 102c and two concave parts 102a.

The code section 104 of the block P2 is
Concave part 102a, concave part 102b, convex part 102c, concave part 10
2a, and the order in which the irregularities are arranged is different from that of the code section 103. Thus, the code units 102 to 111
Are formed so as to obtain a three-bit signal composed of a combination of concave and convex portions, and the probe is formed from an arrangement pattern in which the order of arranging the concave portions 102a, the concave portions 102b, and the convex portions 102c is different as described above. Fifty X-direction scanning positions are detected.

In FIG. 6, the portions indicated by hatching are:
Portions without hatching in the convex portions 101b and 102c are the concave portions 101a, 102a and 102b. Also, the convex portion 1
01b, 102c and recesses 101a, 102a, 102
b is formed to extend in the Y direction orthogonal to the X direction.
For this reason, the probe 50 moves the surface of the calibration sample 100 in the X direction so that the X direction position detection blocks P0 to P
7 can be scanned.

As described above, each X-direction position detection block P
Since the surfaces of 0 to P7 are formed with patterns composed of different combinations of concave portions and convex portions, the position of the probe 50 can be obtained by detecting this pattern. In the present embodiment, the movable range of the fine movement drive unit 53 is set to 60 μm, whereas
The width of P7 in the X direction is set to 40 μm. That is, the width of each of the blocks P0 to P7 is
Is smaller than the movable range of the probe 5
0 contacts any of the blocks P0 to P7 and
If it is moved by 0 μm, it can cross one block. Therefore, since the X-direction scanning position can be detected anywhere in the blocks P0 to P7, the position where the probe 50 is brought into contact can be any of the blocks P0 to P7.

In this embodiment, the dimensions are determined so that the blocks P0 to P7 are square when arranged in a line. Each of the blocks P0 to P7 has a width of 40 μ in the X direction.
m, the total width of the eight blocks P0 to P7 in the X direction is 320 μm, and the length of the blocks P0 to P7 in the Y direction is also 320 μm.

FIG. 8 shows X-direction position detection blocks P0 to P7.
3 shows an example of the position identification pattern formed in FIG. Probe 50
Are obtained by scanning the code section 108 of each of the blocks P0 to P7, "000" for the block P0, "100" for the block P1, and "01" for the block P2.
0 "," 110 "for block P3," 001 "for block P4," 101 "for block P5," 011 "for block P6, and" 11 "for block P7.
A signal such as "1" is a 3-bit signal.

As described above, different position identification codes are obtained from the blocks P0 to P7, and the position of the probe 50 can be specified from the position identification codes. Therefore, while the probe 50 moves in the X direction by 60 μm from the position where the probe 50 first contacts, the pattern formed by the unevenness formed in any one of the blocks P0 to P7 is scanned, and the X-direction scanning position at that time is scanned. Can be accurately detected. Therefore, even if the probe 50 contacts any of the blocks P0 to P7, the position can be detected. Therefore, when the calibration sample 100 and the probe 50 are aligned as in the related art, the coarse movement driving unit 39 is driven. There is no need to perform a troublesome operation of finely moving the probe 50 by driving the fine movement drive unit 53 after coarsely moving the probe 50, and the position detection time of the probe 50 can be reduced.

The Y-direction position detection blocks Q0 to Q7 have the same configuration as the X-direction position detection blocks P0 to P7. The X-direction position detection blocks P0 to P7 are arranged in a direction rotated by 90 °. Things. Therefore, in the Y-direction position detection blocks Q0 to Q7, similarly to the X-direction position detection blocks P0 to P7, a pattern formed of concavities and convexities is formed extending in the X direction orthogonal to the Y direction. Therefore, the probe 50 is connected to the Y-direction position detection blocks Q0 to Q7.
Then, by making the surface scan in the Y direction, the Y direction scanning position can be detected.

As described above, the X direction position of the tip of the probe 50 can be obtained only by finely moving the probe 50 by the fine movement driving unit 53 and moving the surface of the calibration sample 100 in the X direction. Similarly, the position of the tip of the probe 50 in the Y direction can be obtained only by moving the probe 50 in the Y direction.

FIG. 9 is a flowchart for explaining the positioning process executed by the control device 92. The control device 92 executes step S1 (hereinafter, “step” is omitted).
In, the optical microscope 40 is moved in the X and Y directions by the coarse movement drive unit 39 so that the center of the visual field of the optical microscope 40 is aligned with the vicinity of the end point G0 (see FIG. 5) of the calibration sample 100. The center of the visual field of the optical microscope 40 at this time is defined as G1.

In the next step S2, the optical microscope 40 is moved in the Z direction by driving the Z-axis direction drive motor 36 of the coarse movement drive unit 39 to control the focus of the optical microscope 40, and the focus of the optical microscope 40 is adjusted to the calibration sample. Adjust to 100. Subsequently, in S3, the center of the visual field of the optical microscope 40 is
The coarse movement positions Xm, Ym, and Zm in the coarse movement stage coordinate system when they coincide with the end point G0 of 0 are obtained. This is shown in FIG.
As shown in FIG.
The distances X1 and Y1 from the visual field center G1 of the optical microscope 40 to the end point G0 at 0, Y0, and Z0 are obtained, and added to the coarse movement stage coordinate system X0, Y0, Z0, and Xm = X0 +
The calculation may be performed as X1, Ym = Y0 + Y1.

Then, in S4, the coarse movement driving section 39
Is driven to coarsely move the probe 50 above the calibration sample 100. In the next S5, the probe 50 is
Then, it is brought into contact with any of the X-direction position detection blocks P0 to P7, the coarse displacement in the X and Z directions at that time is detected, and the position data X2 and Zp are stored. The probe 5 at this time
The contact position of the calibration sample 100 at 0 is G2.

Subsequently, in S6, the probe 50 is scanned in the X direction by a distance of 52 μm by the fine movement driving unit 53, and a signal corresponding to the uneven shape formed on the surface of the scanned block, the uneven image L _X (FIG. 7 and FIG. 8). S6
In the above, the scanning distance of the probe 50 in the X direction is set to 52 μm because the width of each block in the X direction is 40 μm and the width of the convex portion 101b of the boundary 106 is 12 μm. By doing so, it is possible to completely scan the convex portion 101b of the boundary portion 101 formed in any of the blocks.

That is, the concavo-convex shapes of the boundary portion 101 and the code portion formed in the blocks P3 and P4 are shown in FIG.
When the probe 50 contacts the boundary portion 101 of the block P3 and is scanned in the X direction, the concavo-convex image L _X1 has a signal waveform as shown in FIG. Becomes Further, the probe 50 is connected to the code portion 10 of the block P3.
The concavo-convex image L _X2 when scanned in the X direction by contacting with _{No. 5} is
The signal waveform is as shown in FIG. In any case, the scanning waveform includes a protrusion at the boundary of 12 μm.

[0069] In the next S7, the search for the convex portion 101b of the boundary portion 101 (convex portion width 12 [mu] m) from the topographic image L _x obtained above S6. Then, in S8, extracts the detection signal of the code portion located before and after the convex portion 101b of the boundary 101 from the topographic image L _x, decrypted probe 50 contact the code information of the code portion (scan position information) Block Pi (i is a block number) is determined.

Therefore, in step S6, the probe 50 moves
After scanning by 2 μm, for example, the probe 50
Assuming that the uneven image L _X1 has been obtained across the block 4, the boundary 101 (SB) of the block P 4 is found in S 7, and since the code “110” is found to be the block P 3 in S 8, the boundary found earlier is found. 101 (SB) is the block P
It can be seen that it belongs to the block P4 on the right of 3.

On the other hand, assuming that the uneven image L _X2 is obtained with a slight shift, the code “10” of the two bits after the block P3 is obtained.
And the two-bit code “0” before the code of block P4
0 ". Then, there are only blocks P3 and P4 adjacent to the last two bits of which are "10" and the previous two bits of which are "00", so that the boundary 101 (SB) in this case is the block P4.

[0072] Then, the process proceeds to S9, calculates the X-direction distance X ₃ to the detection signal SB at the boundary 101 from the start point in the topographic image L _x G2. In the next S10, a coarse X position Xp in the coarse stage coordinate system when the probe 50 coincides with the end point G0 of the calibration sample 100 is determined. This is shown in FIG.
As shown in the figure, since the distance in the X direction from the end point G0 to the boundary of the block i is i × 40 μm and the distance in the X direction from the boundary to G2 is X3, the distance X4 in the X direction from the end point G0 to G2 is , I × 40−X3, and the probe 50
Is obtained by subtracting the distance X4 from the coarse movement stage coordinate system X2 when G is in G2, and Xp = X2 + X3-i × 40.

In the following S11 and subsequent steps, processing of the position correction data in the Y direction is executed. That is, in S11, the probe 50
To the Y direction position detection blocks Q0 to Q7 of the calibration sample 100.
The coarse movement displacement in the Y direction at that time is detected, and the position data Y2 is stored. The contact position of the probe 50 with the calibration sample 100 at this time is defined as G3.

[0074] Then, at S12, the probe 50 by the fine movement driving section 53 to scan by a distance of 52μm in Y-direction, the signal is formed on the scanned surface of the block corresponding to the concavo-convex-concave image L _y (FIG. 7 and FIG. 8). Next S1
In 3, the boundary portion from the topographic image L _y obtained above S12 1
06 is searched for a protrusion 102a (a protrusion having a width of 12 μm).
Then, in S14, the boundary portion from the topographic image L _y 106
The detection signal of the code portion 108 located before and after the convex portion 102a is extracted, the code information (scanning position information) of the code portion 108 is decoded, and the block Q with which the probe 50 contacts
j (j is a block number) is determined.

[0075] Then, the process proceeds to S15, and calculates the distance Y ₃ in the Y direction from the start point G3 in the topographic image L _y until the detection signal SB at the boundary 106. In the next S16, a coarse Y position Yp in the coarse stage coordinate system when the probe 50 matches the end point G0 of the calibration sample 100 is determined. This is because, as shown in FIG. 5, the distance in the Y direction from the end point G0 to the boundary of the block j is j × 40 μm, and the distance in the Y direction from the boundary to G2 is Y3. Since the distance in the Y direction is Y3, the distance in the Y direction from G0 to G3 is j × 40−Y3.
3 and the distance Y from the coarse movement stage coordinate system Y2.
3 is subtracted to obtain Yp = Y2 + Y3-J × 40.

[0076] Then, the relative precision location of the axis of the optical microscope 40 and the probe _{50 X f = Xm-Xp,} Y f = Ym-Y
p, calculates the Z _f = Zm-Zp. Therefore, after the position of the fine wiring to be inspected by the optical microscope 40 is set, the amount of displacement of the probe 50 with respect to the optical microscope 40 (relative precision position X _f ,
By finely moving the probe 50 after correcting Y _f , Z _f ), the probe 50 can be accurately brought into contact with a desired fine wiring.

FIG. 11 shows a first modification of the calibration sample. The calibration sample 112 has exactly the same configuration as the calibration sample 100 of the above embodiment in the X-direction position detection blocks P0 to P7.
The direction position detection blocks Q0 to Q7 are formed with the same width (40 μm) as the X direction position detection block. That is, if the position detection in the X direction can be performed, it is sufficient for the position detection in the Y direction to have a width of one block.

Therefore, the entire width of the calibration sample 112 is smaller than that of the calibration sample 100, and the size can be reduced. FIG. 12 shows a second modification of the calibration sample. Calibration sample 1
Reference numeral 14 denotes Y direction position detection blocks Q0 to Q7 having a width of 8 μm formed between the same X direction position detection blocks P0 to P7 as the calibration sample 100 of the above embodiment. That is,
After the probe 50 is in contact with any of the blocks P0 to P7 to perform position detection in the X direction, the probe 50 is finely moved to the adjacent Y direction position detection blocks Q0 to Q7 to detect the position in the Y direction. It can be carried out.

Therefore, the calibration sample 114 can be downsized by making the overall width smaller than that of the calibration sample 100, and the position in the Y direction can be detected without coarsely moving the probe 50. Can be shorter. FIG. 13 is a diagram showing a block pattern of a third modification of the calibration sample, and FIG. 14 is a diagram showing the block in an enlarged manner.

The calibration sample 120 includes a position detection block P0
0 to P77 are arranged in a matrix. The blocks P00 to P77 do not have the uneven portion extending in the X direction.
Position information is coded by the concave and convex portions extending in the Y direction. In order to distinguish the 64 blocks P00 to P77 in total, a boundary portion 121 having a width of 10 μm and code portions 122 to 125 having a width of 30 μm are provided.
Each of 22 to 125 and the like is composed of 6 bit portions each having a width of 5 μm. Each bit has a recess 122a or 2.5 μm
Of the concave portion 122b and the convex portion 122c of 2.5 μm.

In FIG. 14, blocks P00 to P77
Of these, only the blocks P00, P01, P10, and P11 are shown in an enlarged manner. Code part 122 of block P00
Is composed of six concave portions 122a, and the code portion 123 of the block P01 is composed of concave portions 122b, convex portions 122c, and five concave portions 122a.

The code part 124 of the block P10 is similarly composed of a concave part 122b, a convex part 122c and five concave parts 122a, but the order of arrangement is different from that of the block P01. Also,
Similarly, the code portion 125 of the block P11 includes two concave portions 122b, a convex portion 122c, and four concave portions 122a. Further, the width of each block in the Y direction is 40 μm, and a protrusion 126
Are formed to extend in the X direction.

Therefore, when the probe 50 is scanned by 45 μm, it is possible to determine which of the blocks P00 to P77 has contacted. Therefore, not only the positions in the X direction from the block positions arranged in a matrix
The position in the Y direction can be seen in the range of 7.5 μm. Further, by scanning the probe 50 by 40 μm in the Y direction, the probe 50 is scanned.
Is in contact with the convex portion 126 and passes therethrough, so that Y
The exact position of the direction can be determined.

In the above embodiment, the boundary portion and the cord portion are separated from each other. However, the present invention is not limited to this, and the boundary portion may be formed in the cord portion by changing the depth of the concave portion. It is possible. Further, in the above-described embodiment, the code portion is binarized by the unevenness, but it is also possible to multi-value by changing the depth stepwise.

In the above embodiment, the two convex portions are not formed continuously in the cord portion. However, the present invention is not limited to this.
It is also possible to form two or three or more convex portions continuously.

[0086]

According to the present invention as described above, the following various effects can be realized. According to the first aspect of the present invention, the probe is brought into contact with the surface of a calibration sample having a plurality of position detection blocks in which different position identification patterns formed by unevenness extending in one direction are individually formed. To detect the scanning position of the probe from the combination of
The position of the probe can be easily measured, and the time required to detect the position of the probe can be reduced. Therefore, the relative position between the focal point of the optical microscope and the tip of the probe can be measured at high speed and reliably even if the displacement of the probe at the time of replacement of the probe does not fall within the fine movement range.

According to the second aspect of the present invention, in the probe position correcting apparatus, when the probe comes into sliding contact with one of the position detection blocks formed on the surface of the calibration sample to detect the position identification pattern, the position identification pattern is detected. To generate coded scanning position information from a combination of patterns, calculate the coordinate position where the probe is in contact from the scanning position information, and correct the scanning position of the probe based on the detected coordinate position. In addition, the time required for detecting the position of the probe can be reduced, and the scanning position of the probe can be accurately corrected. Therefore, the relative position between the focal point of the optical microscope and the tip of the probe can be measured at high speed and reliably even if the displacement of the probe at the time of replacement of the probe does not fall within the fine movement range.

According to the third aspect of the present invention, in the fine wiring inspection apparatus, each side of the calibration sample is formed to have a size smaller than the operating range of the fine movement driving unit, and the probe is formed on the surface of the calibration sample. The position identification block is slid into contact with the other position detection block to detect the position identification pattern, generate coded scanning position information from the combination of the position identification pattern, and calculate the coordinate position where the probe touched from the scanning position information. To correct the scanning position of the probe based on the detected coordinate position, thereby shortening the time required to detect the position of the probe,
The scanning position of the probe can be accurately corrected. Therefore, the relative position between the focal point of the optical microscope and the tip of the probe can be measured at high speed and reliably even if the displacement of the probe at the time of replacement of the probe does not fall within the fine movement range.

According to the fourth aspect of the present invention, a position identification pattern is formed on the surface of the calibration sample with which the probe comes into contact by means of unevenness extending in one direction, and the probe is slid on the unevenness to identify the position. A probe position correction method that detects a pattern and corrects the scanning position of the probe that has come into contact with the calibration sample from the combination of the position identification patterns can shorten the time required to detect the position of the probe, and Can be accurately corrected. Therefore, the relative position between the focal point of the optical microscope and the tip of the probe can be measured at high speed and reliably even if the displacement of the probe at the time of replacement of the probe does not fall within the fine movement range.

According to the fifth aspect of the present invention, the position identification pattern is detected by bringing the probe into sliding contact with the position identification pattern formed on the surface of the calibration sample. Generating the calculated scanning position information, calculating a coordinate position where the probe is in contact with the scanning position information, and correcting the scanning position of the probe based on the calculated coordinate position. The probe position correction method can shorten the time required to detect the position of the probe, and can correct the scanning position of the probe accurately. Therefore, the relative position between the focal point of the optical microscope and the tip of the probe can be measured at high speed and reliably even if the displacement of the probe at the time of replacement of the probe does not fall within the fine movement range.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of an embodiment of a fine wiring inspection apparatus using a calibration sample according to the present invention.

FIG. 2 is a configuration diagram showing a state in which a probe is moved to a measurement sample.

FIG. 3 is an enlarged longitudinal sectional view showing a configuration of a probe holding unit.

FIG. 4 is a block diagram of a probe position correcting device.

FIG. 5 is a plan view showing the shape of a calibration sample of the present invention.

FIG. 6 is an enlarged plan view showing a position detection block of a calibration sample.

FIG. 7 is a vertical sectional view taken along line A-A 'in FIG.

FIG. 8 is a diagram illustrating an example of a position identification pattern formed in X-direction position detection blocks P0 to P7.

FIG. 9 is a flowchart illustrating a positioning process performed by the control device.

FIG. 10 is a diagram for explaining a procedure for detecting a block of a calibration sample by scanning a probe.

FIG. 11 is a plan view showing a first modification of the calibration sample.

FIG. 12 is a plan view showing a modification 2 of the calibration sample.

FIG. 13 is a plan view showing a third modification of the calibration sample.

FIG. 14 is an enlarged view showing a concavo-convex pattern of a modification 3 of the calibration sample.

FIG. 15 is an enlarged view showing a configuration in which a probe is magnetically attracted.

FIG. 16 is an enlarged view for explaining that a displacement occurs when the probe is magnetically attracted.

FIG. 17 is a view for explaining a conventional calibration sample.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Anti-vibration stand 11 Base 12 Measurement sample 16 Y-axis direction guide rail 18 Y-axis direction table 22 X-axis direction table 24 X-axis direction drive motor 30 Switching stage 32 Z-axis direction guide rail 34 Focus adjustment stage 36 Z-axis direction drive motor 39 Coarse movement drive unit 40 Optical microscope 42 Evacuation stage 44 Z-axis direction drive motor 46 Scanning probe microscope 48, 49 Moving stage 50 Probe 51 Probe holding unit 52 Actuator 53 Fine movement drive unit 60, 62 Cross beam 64, 66, 68 Conductive plate 70 Holder 72 Hollow rod 80 Voltage information generating element 82 Permanent magnet 84 Magnetic material 90 Probe position correcting device 92 Control device 94 Capacitance detecting circuit 100, 112, 114, 120 Calibration sample 101, 121 Boundary part 101a, 102b, 121a, 122a, 12 b
Concave portions 101b, 102c, 121b, 122c, 126 Convex portions 102 to 104, 122 to 125 Cord portion

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/66 H01L 21/66 S

Claims (5)

[Claims] 1. A method according to claim 1, further comprising: a plurality of position detection blocks in which different position identification patterns formed by unevenness extending in one direction are individually formed on a surface with which the probe comes in contact. A calibration sample characterized by detecting a scanning position. 2. A calibration sample having a plurality of position detection blocks in which different position identification patterns formed by unevenness extending in one direction are individually formed on a surface with which a probe contacts, and the probe is moved to the surface of the calibration sample. A scanning position information generating unit that detects the position identification pattern by slidingly contacting one of the position detection blocks formed therein, and generates coded scanning position information from a combination of the position identification patterns; A probe position detection unit that calculates a coordinate position where the probe is in contact with the scanning position information generated by the generation unit; and scanning of the probe based on the coordinate position detected by the probe position detection unit. A probe position correction device, comprising: a correction calculation unit that corrects a position; 3. A fine-movement drive so that a fine wiring formed on a sample to be measured is imaged by an imaging unit, and a probe is brought into contact with the fine wiring of the sample to be measured based on image information captured by the imaging unit. A fine wiring inspection device for driving fine parts and coarse movement driving parts to test fine wiring of the sample to be measured, wherein each side is formed to have a size smaller than an operation range of the fine movement driving parts, and the probe is brought into contact with the fine movement driving part. A calibration sample having a plurality of position detection blocks in which different position identification patterns due to unevenness extending in one direction on the surface are individually formed, and the probe is attached to one position detection block formed on the surface of the calibration sample. A scanning position information generating unit for detecting the position identification pattern by sliding contact, and generating coded scanning position information from a combination of the position identification patterns; A probe position detecting unit that calculates a coordinate position where the probe is in contact with the scanning position information generated by the component unit; and scanning of the probe based on the coordinate position detected by the probe position detecting unit. A fine wiring inspection device, comprising: a correction operation unit that corrects a position. 4. A position identification pattern formed by unevenness extending in one direction is formed on a surface of a calibration sample contacted by a probe, and the probe is slid into contact with the unevenness to detect the position identification pattern. A method of correcting a probe position, comprising: correcting a scanning position of the probe in contact with the calibration sample from a combination of position identification patterns. 5. A method in which a probe is slid into contact with a position identification pattern formed on the surface of a calibration sample to detect the position identification pattern, and then generates coded scanning position information from a combination of the position identification patterns. And calculating a coordinate position at which the probe is in contact with the scanning position information, and correcting the scanning position of the probe based on the calculated coordinate position.