CN108662985B - Surface profile scanning method and device - Google Patents

Abstract

The present invention discloses a surface profile scanning method and device thereof, the method comprising the following steps: setting a scanning area, setting a test piece into at least one scanning area and at least one moving area; performing scanning, an interference objective lens arranged in a scanning unit moves in the scanning area, so that the scanning unit scans the test piece in the scanning area and obtains a scanning information, and performs calculation on the scanning information to form a scanning profile value corresponding to the scanning area; a moving module coupled to the scanning unit controls the scanning unit to move a predetermined distance in the moving area, and when the scanning unit does not scan, sets a predetermined profile value corresponding to the moving area; and obtaining a surface profile, the predetermined profile value is combined with the scanning profile value to obtain the surface profile of the test piece.

Description

Surface profile scanning method and device

technical field

The present invention relates to a surface profile scanning method and device, and more particularly, to a method and device for scanning the surface profile of a test piece.

Background technique

White light interferometry is usually used in the detection of three-dimensional topography. In the existing three-dimensional topography detection method, a test piece is divided into several positions to be measured, and a white light is projected to a position to be measured on the test piece through an interference objective lens. The interferometric objective is moved in an axial direction so that the white light is projected to different axial positions of the position to be measured.

In order to obtain the surface profile of the test piece, the interferometric objective lens is moved in an axial direction by a plurality of predetermined distances at each position to be measured on the test piece, and a vision module respectively obtains a plurality of images at each predetermined distance, and the plurality of images can range from hundreds to Thousands of images.

As mentioned above, the test piece has several positions to be tested. If hundreds or thousands of images are obtained at each position to be tested, the total number of images will be very considerable, and interpretation will be difficult. In addition, the interference objective lens moves axially at a large distance relative to each position to be measured, so the moving module driving the interference objective lens is easily damaged under long-term use.

In addition, when scanning the surface profile of the test piece, based on requirements, the operator usually pays more attention to the upper and lower ranges of the surface profile when inspecting the features of the surface profile of the test piece. Less attention, when the height difference of the surface profile of the test piece is too large, the existing three-dimensional topography detection method still scans the overall height of the axial direction of the position to be measured of the test piece, that is, the operator is less concerned about it. The mid-range of the s is also scanned together, so the overall scanning time will increase, which is not in line with the use efficiency.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a surface profile scanning method and device thereof, which can reduce the number of captured scanned images and scan only the set position of the test piece, so as to increase the scanning rate and reduce the probability of damage to the scanning device .

According to the above-mentioned purpose, the present invention proposes a surface profile scanning method, which comprises the following steps:

setting a scanning area, and setting a test piece as at least one scanning area and at least one moving area;

Scanning is performed, an interferometric objective lens set in a scanning unit moves in the scanning area, so that the scanning unit scans the test piece in the scanning area, and obtains a scanning information, and the scanning information is calculated to form A pair of scanning contour values of the scanning area; a moving module coupled to the scanning unit controls the scanning unit to move a predetermined distance in the moving area, and when the scanning unit is not scanning, a predetermined value corresponding to the moving area is set contour values; and

A surface profile is derived, and the predetermined profile value is combined with the scanned profile value to derive the surface profile of the test piece.

The present invention also provides a surface profile scanning device, which includes:

a mobile module;

a scanning unit coupled to the moving module, the scanning unit having a vision module and an interference objective lens; and

an integrated unit connected to the scanning unit;

Wherein, the moving module controls the scanning unit to move in an axial direction relative to a test piece; the interference objective lens moves in an axial direction relative to the test piece; the test piece is set to at least one scanning area and at least one moving area; The scanning unit provides a test beam, the test beam passes through the interference objective lens to project to the scanning area, and forms a reflected beam, the reflected beam passes through the interference objective lens and is directed to the vision module and received by the vision module, thereby forming a a scanning information, the integration unit calculates the scanning information to form a pair of scanning contour values of the scanning area; the moving module controls the scanning unit to move a predetermined distance in the moving area, when the scanning unit is not scanning, set A predetermined contour value corresponding to the moving area; the integration unit is combined with the scanning contour value and the predetermined contour value to obtain the surface contour of the test piece.

In an embodiment of the present invention, in the above step of performing scanning, the scanning unit scans the scanning area first, and then the scanning unit moves in the moving area; or the scanning unit moves before the moving area, and the scanning unit moves after the scanning unit. Scan this scan area.

In an embodiment of the present invention, the scanning unit has a first lens, a beam splitter, a second lens, a light source and a piezoelectric micro-actuator, the first lens is located below the vision module, the The beam splitter is located below the first lens, the second lens is located on one side of the beam splitter, the light source is located on one side of the second lens, the piezoelectric micro-actuator is located below the beam splitter, the piezoelectric The micro-actuator is coupled to the interference objective lens, the light source provides the test beam, the test beam passes through the second lens, the beam splitter and the interference objective lens and then projects to the test piece, and forms the reflected beam, the reflected beam It is received by the vision module after passing through the interference objective lens, the beam splitter and the first lens.

Based on the above, in the surface profile scanning method and device provided by the present invention, the scanning unit moves a large Z-axis relative to the moving area without scanning, so the scanning unit only scans the scanning area, so the overall scanning time can be reduced. The piezoelectric micro-actuator moves a small Z-axis relative to the scanning area, so the interference objective lens can move axially a short distance relative to each position to be measured, so the damage rate of the piezoelectric micro-actuator can be reduced .

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are given and described in detail with the accompanying drawings as follows.

Description of drawings

1 is a schematic diagram of a surface profile scanning device provided by the present invention;

Fig. 2 is the schematic diagram of the test position of a test piece;

3A is a schematic diagram of at least one scanning area, at least one overlapping area and at least one moving area;

3B is another schematic diagram of the height direction of the scanning area, the overlapping area and the moving area;

3C is a partial schematic view of the height direction of the scanning area, the overlapping area and the moving area;

3D is another partial schematic diagram of the height direction of the scanning area, the overlapping area and the moving area;

FIG. 4 is a schematic diagram of a surface profile scanning method according to the present invention.

Description of reference numerals: 1-scanning unit; 10-vision module; 11-first lens; 12-spectroscope; 13-interference objective lens; 14-piezoelectric micro-actuator; 15-second lens; 16-light source; 160-test beam; 17-movement module; 18-integration unit; 20-test piece; 200-test position; 201-scanning area (first scanning area); 202-moving area; 203-scanning area (second scanning area) ); 204-reflected beam; 205-overlapping region; S1-S4-step.

Detailed ways

As shown in FIG. 1 , the present invention provides a surface contour scanning device, which includes a scanning unit 1 , a moving module 17 and an integrating unit 18 .

The scanning unit 1 has a vision module 10 , a first lens 11 , a beam splitter 12 , an interference objective lens 13 , a piezoelectric micro-actuator 14 , a second lens 15 , and a light source 16 .

The first lens 11 is located below the vision module 10 . The beam splitter 12 is located below the first lens 11 . Piezoelectric microactuator 14 is located below beam splitter 12 . The interference objective 13 is coupled to the piezoelectric microactuator 14 . The second lens 15 is located on one side of the beam splitter 12 . The light source 16 is located on the side of the second lens 15 away from the beam splitter 12 . The light source 16 is a white light, and the light source 16 can be optionally arranged inside the scanning unit 1 , or arranged outside the scanning unit 1 , and then guides the light beam to the scanning unit 1 .

The moving module 17 is coupled to the scanning unit 1 , and the moving module 17 controls the scanning unit 1 to move in an axial direction relative to a test piece 20 .

The integration unit 18 is connected with the scanning unit 1 and the moving module 17 .

As shown in FIG. 1 to FIG. 4 , the present invention also provides a surface profile scanning method, which includes the following steps:

Step S1, scan the test piece. A test piece 20 is moved to below the scanning unit 1 by being transferred on a stage (not shown). The piezoelectric micro-actuator 14 drives the interference objective lens 13 to move the interference objective lens 13 relative to a test piece 20 in an axial direction, so as to scan the surface profile of the test piece 20 .

In this step, as shown in FIG. 2 , the test piece 20 is divided into a plurality of test positions 200 . The above scanning may correspond to a single test position 200 or a plurality of test positions 200, and the surface profile obtained by scanning is used for setting the at least one scanning area 201, 203 and the at least one moving area 202 in step S2.

For further explanation, the moving module 17 drives the scanning unit 1 to move, so that the interference objective lens 13 moves relative to one of the test positions 200 of the test piece 20 along the large Z-axis (axial). The light source 16 provides a test beam 160 , the test beam 160 passes through the second lens 15 and the beam splitter 12 , the test beam 160 passes through the interference objective lens 13 , and is projected to the test position 200 of the test piece 20 to form a reflected beam 204 . The reflected light beam 204 passes through the interference objective lens 13 , the beam splitter 12 and the first lens 11 to be received by the vision module 10 . The receiving of the aforementioned test beam 160 , the reflected beam 204 and the vision module 10 is a scanning action. The integration unit 10 receives the image information of the reflected light beam 204 from the vision module 10 to obtain the surface profile of the test piece 20 .

Step S2, setting the scanning area. As shown in FIG. 2 , the test piece 20 has a plurality of test locations 200 .

As shown in FIG. 3A , the surface contour of each test position 200 of the test piece 20 is set as at least one scanning area 201 , 203 and at least one moving area 202 . For further explanation, as shown in FIG. 2 , the height direction (axial direction) of each test position 200 is set to at least one scanning area 201 , 203 and at least one moving area 202 . The scanning areas 201 , 203 are adjacent to the moving area 202 . Alternatively, the moving area 202 overlaps with the scanning areas 201 and 203 , that is, there is an overlapping area 205 between the moving area 202 and the scanning areas 201 and 203 , and the degree of overlap is a partial overlap. The aforementioned adjacency should be defined as if the scanning areas 201 and 203 are located in the upper and lower sections of each test position 200 , the moving area 202 is located in the middle range of each test position 200 , that is, the upper and lower sections of the moving area 202 are the scanning area 201 respectively. , 203, but not limited.

As shown in FIG. 3B , that is, the scanning area 201 may be adjacent to the moving area 202 , and the overlapping area 205 may optionally be present; or, the scanning area 203 may be adjacent to the moving area 202 without the overlapping area 205 . The aforementioned degree of overlap is complete overlap, which depends on the actuation direction of the piezoelectric micro-actuator 14 , so as to facilitate the measurement of the test position of the test piece 20 .

In another embodiment, the above-mentioned step S1 is not performed on the test piece 20 . As shown in FIG. 2 and FIG. 3A , the test piece 20 is divided into a plurality of test positions 200 , and each test position 200 is set as at least one scanning area 201 , 203 and at least one moving area 202 . As mentioned above, there is an overlap area 205 between the moving area 202 and the scanning areas 201 and 203 .

For ease of discussion, the above-mentioned at least one scanning area 201 may be regarded as the first scanning area 201 , and the above-mentioned at least one scanning area 203 may be regarded as the second scanning area 203 . The component symbols of the first scan area 201 and the second scan area 203 are the same as the component symbols of the at least one scan area 201 and 203 described above, which are specially stated first. The first scanning area 201 distinguishes the surface profile of each test position 200 with a first ratio. The second scanning area 202 distinguishes the surface profile of each test position 200 by a third ratio. The first ratio is equal to, greater than or less than the third ratio, which is set according to the actual situation, so it is not limited.

Similarly, the moving area 202 distinguishes the surface contour of each test position 200 by a second ratio. The first scanning area 201 is adjacent to the moving area 202 . The second scanning area 203 is adjacent to the moving area 202 . The moving area 202 is located between the first scanning area 201 and the second scanning area 203 .

Step S3, scan is performed. As shown in FIG. 1 and FIG. 2 , the scanning unit 1 scans a test position 200 of the test piece 20 .

As shown in FIG. 3A and FIG. 1 , the piezoelectric micro-actuator 14 drives the interference objective lens 13 to move the interference objective lens 13 relative to the test piece 20 in an axial direction. For ease of discussion, the axial movement here is defined as small Z-axis movement, but not limited.

When the interference objective lens 13 moves relative to the first scanning area 201 in a small Z-axis, the scanning unit 1 scans the first scanning area 201 and obtains scanning information, which can be regarded as the first scanning information.

After the first scanning area 201 is scanned, the scanning unit 1 stops scanning. The piezoelectric actuator 14 stops working. The moving module 17 drives the scanning unit 1, so that when the scanning unit 1 moves a predetermined distance relative to the moving area 202, the scanning unit 1 does not scan. And set a predetermined contour value corresponding to the moving area 202 . For the convenience of description, the predetermined distance moved may be defined as a large Z-axis movement, which will be discussed in the following paragraphs as a large Z-axis movement, but is not limited.

For further discussion, the moving module 17 drives the scanning unit 1 to move the scanning unit 1 relative to the moving area 202 in the large Z-axis, and a predetermined contour value corresponding to the moving area 202 has been set in advance, which is preset by the user. The predetermined contour value of the moving area 202 is determined.

After the scanning unit 1 has performed a large Z-axis movement, the piezoelectric micro-actuator 14 drives the interference objective lens 13 again, so that the interference objective lens 13 performs a small Z-axis movement relative to the second scanning area 203 . The scanning unit 1 scans the second scanning area 203, and obtains scanning information, which can be regarded as the second scanning information.

As shown in FIG. 1 , the integration unit 18 receives the first scan information and performs operations on the first scan information to form a first scan contour value corresponding to the first scan area 201 . The integration unit 18 receives the second scan information and performs operations on the second scan information to form a second scan profile value corresponding to the second scan area 203 .

As described above, in this step, the moving module 17 can make the scanning unit 1 move in the large Z-axis first, and the scanning unit 1 does not scan. When the piezoelectric micro-actuator 14 moves the interference objective lens 13 in the small Z-axis, the scanning unit 1 scans and captures the image of the test piece 20 . The moving module 17 controls the scanning unit 1 to move in a large Z-axis, and the scanning unit 1 does not scan. The piezoelectric micro-actuator 14 then makes the interference objective lens 13 move in a small Z-axis, and the scanning unit 1 scans.

Alternatively, the piezoelectric micro-actuator 14 first moves the interference objective lens 13 in a small Z-axis, and the scanning unit 1 performs scanning. The moving module 17 then controls the scanning unit 1 to move in the large Z-axis, and the scanning unit 1 does not scan. The piezoelectric micro-actuator 14 then controls the interference objective lens 13 to move in a small Z-axis, and the scanning unit 1 scans.

In summary, the sequence of the large Z-axis movement of the scanning unit 1 and the small Z-axis movement of the interference objective lens 13 is not limited to the embodiment of the present invention, and the large Z-axis movement and the small Z-axis movement are changed according to the actual situation. The sequence of moves.

The distance moved by the large Z-axis movement described above is greater than the distance moved by the small Z-axis movement. For further explanation, as shown in FIG. 3A , the above-mentioned length of the large Z-axis is the length of the moving area 202 . The length of the above-mentioned small Z axis is the length of the scanning areas 201 and 203 . Alternatively, the length of the above-mentioned large Z-axis is the distance between the two overlapping regions 205 . Alternatively, the length of the above-mentioned small Z is the length of the scanning areas 201 and 203 minus the length of the overlapping area 205 .

As shown in FIG. 3C , the piezoelectric micro-actuator 14 first moves the interference objective lens 13 in a small Z-axis, and the scanning unit 1 scans the first scanning area 201 . The moving module 17 then controls the scanning unit 1 to move in the large Z-axis, and the scanning unit 1 does not scan. As shown in FIG. 3C , when the moving module 17 controls the scanning unit 1 to perform a large Z-axis movement, the movement can be started by the moving area 202 . When the large Z-axis movement is performed, the piezoelectric micro-actuator 14 can also choose to make the interference objective lens 13 perform a small Z-axis movement or not move.

As shown in FIG. 3D , the moving module 17 then controls the scanning unit 1 to move in the large Z-axis, and the scanning unit 1 does not scan. The piezoelectric micro-actuator 14 then makes the interference objective lens 13 move in a small Z-axis, and the scanning unit 1 scans the second scanning area 203 . As shown in FIG. 3D , when the piezoelectric micro-actuator 14 makes the interference objective lens 13 move in a small Z-axis, the movement can be started by the second scanning area 203 . When the small Z-axis movement is in progress, the large Z-axis movement does not act.

As described above, as shown in FIGS. 3A to 3D , when the moving module 17 controls the scanning unit 1 to perform a large Z-axis movement, the piezoelectric micro-actuator 14 can selectively make the interference objective lens 13 perform a small Z-axis movement or no movement. If the piezoelectric micro-actuator 14 controls the interference objective lens 13 to perform small Z-axis movement and the scanning unit 1 scans, the moving module 17 does not work, that is, the moving module 17 does not control the scanning unit 1 to perform large Z-axis movement.

For further discussion, as shown in FIGS. 3A and 3B , when the moving module 17 controls the scanning unit 1 to perform a large Z-axis movement, the interference objective lens 13 is still within the range of the overlapping area 205 , so the piezoelectric micro-actuator 14 The interference objective lens 13 can still be moved by a small Z-axis, so that the scanning unit 1 can scan continuously or adjust the position of the interference objective lens 13 relative to the test position 200 of the test piece 20 .

In step S4, the surface profile is obtained. The integration unit 18 combines the first scanned profile value, the predetermined profile value and the second profile value to derive the surface profile of the scanned test location 200 of the test piece 1 . If the remaining test positions 200 are still to be scanned, go back to step S1. Stop if the remaining test locations 200 are not to be scanned.

To sum up the above, the present invention divides the axial height to be measured at each test position 200 of the test piece 200 into at least one scanning area 201 , 203 and at least one moving area 202 . The interferometric objective lens 13 performs a small Z-axis movement relative to the scanning areas 201, 203, so that the scanning unit 1 scans to obtain a scanning profile value. The scanning unit 1 performs a large Z-axis movement relative to the moving area 202 without scanning, and firstly sets a predetermined contour value. The integration unit 18 combines the predetermined profile values with the scanned profile values to derive the surface profile of the test piece 20 .

Since the scanning unit 1 does not scan in the moving area 202, and the scanning unit 1 only scans in the scanning areas 201 and 203, the present invention can only scan the characteristic areas of the test piece 20, that is, the scanning areas 201 and 203, so it can be The stroke of the measurement scan is greatly reduced, and is not limited by the height of the test piece 20 and the movement stroke of the piezoelectric actuator 14 .

Due to the small Z-axis movement of the piezoelectric micro-actuator 14 relative to the scanning areas 201 and 203, the interference objective lens 13 can be axially moved at a short distance relative to each position to be measured 200, so the piezoelectric micro-actuator can be reduced. Destruction rate of the actuator 14 .

The scanning unit 1 performs a large Z-axis movement relative to the moving area 202 and does not perform scanning, so the scanning unit 1 only scans the scanning areas 201 and 203, so the overall scanning time can be reduced. In addition, the number of images acquired by the vision module 10 of the scanning unit 1 can be reduced, so the difficulty in interpretation can be reduced.

To sum up, although the present invention is disclosed by the above examples, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope of the claims in this case.

Claims (10)

1. a surface profile scanning method, is characterized in that, comprises the following steps: setting a scanning area, and setting a test piece as at least one scanning area and at least one moving area; Scanning is performed, an interferometric objective lens set in a scanning unit moves in the scanning area, so that the scanning unit scans the test piece in the scanning area, and obtains a scanning information, and the scanning information is calculated to form A pair of scanning contour values of the scanning area; a moving module coupled to the scanning unit controls the scanning unit to move a predetermined distance in the moving area, and when the scanning unit is not scanning, a predetermined value corresponding to the moving area is set Contour value, a piezoelectric micro-actuator coupled to the interference objective lens drives the interference objective lens, so that the interference objective lens moves in an axial direction relative to the test piece, when the interference objective lens moves, the scanning unit scans the test piece to obtain the surface profile of the test piece; and A surface profile is derived, and the predetermined profile value is combined with the scanned profile value to derive the surface profile of the test piece. 2. surface profile scanning method as claimed in claim 1 is characterized in that: In the step of setting the scanning area, the scanning area is obtained by dividing the surface contour with a first scale, and then the surface contour is divided according to a second scale to obtain the moving area. The scanning area and the moving area are set in the step of setting the scanning area. 3. The surface contour scanning method of claim 1, wherein in the step of setting the scanning area, the scanning area is obtained by dividing the surface contour of the test piece with a first ratio, and then The moving area is obtained by dividing the surface profile at a second scale. 4. The surface profile scanning method as claimed in claim 2 or 3, wherein in the step of setting a scanning area, the test piece has a plurality of test positions, and the scanning area is respectively set at each test position with the mobile area. 5 . The surface contour scanning method of claim 4 , wherein, in the step of setting the scanning area, the surface contour is distinguished by a third ratio to obtain at least another scanning area, the third ratio is 5 . greater than, equal to or less than the first ratio; in the step of performing scanning, the interference objective lens moves in the other scanning area, the scanning unit scans the other scanning area to obtain another scanning information, the other scanning information A scan information forms another scan contour value corresponding to the other scan area; in the step of deriving the contour value, the predetermined contour value is combined with the scan contour value and the other scan contour value to obtain the surface profile. 6 . The surface contour scanning method of claim 1 , wherein in the step of performing scanning, the scanning unit scans the scanning area first, and then the scanning unit moves in the moving area; or the scanning unit precedes the scanning unit. 7 . The moving area moves, and the scanning unit then scans the scanning area. 7 . The surface profile scanning method of claim 2 , wherein in the step of scanning the test piece, the test piece is divided into a plurality of test positions, and the scanning unit scans a single test position or a plurality of test positions. 8 . 8 . The surface contour scanning method of claim 1 , wherein in the step of setting the scanning area, the scanning area is adjacent to the moving area, or the scanning area and the moving area overlap. 9 . 9. A surface profile scanning device, characterized in that it comprises: a mobile module; a scanning unit coupled to the moving module, the scanning unit having a vision module and an interferometric objective lens, the scanning unit having a piezoelectric micro-actuator coupled to the interferometric objective lens; and an integrated unit connected to the scanning unit; The moving module controls the scanning unit to move in an axial direction relative to a test piece; the piezoelectric micro-actuator drives the interference objective lens, so that the interference objective lens moves in an axial direction relative to the test piece. When the interference objective lens moves, the scanning unit scans the test piece; the test piece is set to at least one scanning area and at least one moving area; the scanning unit provides a test beam, and the test beam passes through the interference objective lens to project to the scanning area, and form a reflected beam, the reflected beam is guided to the vision module after passing through the interference objective lens and received by the vision module, thereby forming a scan information, the integration unit calculates the scan information to form a pair of scans of the scan area contour value; the moving module controls the scanning unit to move a predetermined distance in the moving area, and when the scanning unit is not scanning, a predetermined contour value corresponding to the moving area is set; the integration unit and the scanning contour value and the predetermined contour value The profile values are combined to derive the surface profile of the test piece. 10 . The surface contour scanning device of claim 9 , wherein the scanning unit has a first lens, a beam splitter, a second lens and a light source, the first lens is located below the vision module, 11 . The beam splitter is located below the first lens, the second lens is located on one side of the beam splitter, the light source is located on one side of the second lens, the piezoelectric micro-actuator is located below the beam splitter, the light source Provide the test beam, which is projected to the test piece after passing through the second lens, the beam splitter and the interference objective lens, and forms the reflected beam, and the reflected beam passes through the interference objective lens, the beam splitter and the first lens It is then received by the vision module.

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