Method, device and electronic device for determining objective lens optical axis position of exposure equipment

Abstract

The present application provides a method, device and electronic device for determining the position of the objective lens optical axis of an exposure device, the method comprising: using a sensor to detect the energy value of a first projection light spot, and determining the reference position of the objective lens optical axis within the range of the first projection light spot; using a sensor to detect the energy value of a second projection light spot, and determining the target position within the range of the second projection light spot; based on the target position, using a search algorithm to determine the offset position of the objective lens optical axis within the range of the second projection light spot; determining the offset distance of the offset position relative to the reference position, and using the offset distance to determine the position of the objective lens optical axis when the second mask is used alone. By adopting the above-mentioned method, device and electronic device for determining the position of the objective lens optical axis, the problem of cumbersome measurement process and low measurement efficiency caused by using a tooling mask for measurement every time when measuring the position of the objective lens optical axis is solved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a method, device and electronic device for determining the optical axis position of an objective lens of an exposure device. Background Art

[0002] With the continuous development of semiconductor technology, the requirements for the precision of exposure equipment are getting higher and higher. The early calibration of exposure equipment is crucial to improve the precision. Since the objective lens plays a very important role in the exposure equipment, the position calibration of the objective lens optical axis is also an important part of improving the precision of the exposure equipment. Before calibrating the position of the objective lens optical axis, it is first necessary to use hardware equipment to determine the position of the objective lens optical axis. The hardware equipment includes light source, tooling mask, special mask, sensor, shading mechanism, etc.

[0003] At present, the commonly used method for measuring the optical axis position of the objective lens is to load a high-precision tooling mask in the exposure equipment, and determine the optical axis position of the objective lens by using the position of the light beam passing through the light hole of the tooling mask and the projection spot behind the objective lens. However, the high-precision tooling mask is expensive and the disassembly and installation process is complicated. If the optical axis position of the objective lens is measured by loading the tooling mask every time, not only will the process be cumbersome, but it will also lead to low measurement efficiency and a rapid reduction in the service life of the tooling mask. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a method, device and electronic device for determining the optical axis position of the objective lens of an exposure device, so as to solve the problems of cumbersome measurement process and low measurement efficiency caused by using a tooling mask for measurement each time when measuring the optical axis position of the objective lens.

[0005] In a first aspect, an embodiment of the present application provides a method for determining an optical axis position of an objective lens of an exposure device, comprising:

[0006] The sensor is used to detect the energy value of the first projection light spot, and the reference position of the optical axis of the objective lens within the range of the first projection light spot is determined. The first projection light spot is a light spot formed after the light beam emitted by the light source passes through the central light hole of the first mask and the objective lens in sequence.

[0007] The sensor is used to detect the energy value of the second projection spot and determine the target position within the second projection spot. The second projection spot is a spot formed after the light beam emitted by the light source passes through the central light hole of the second mask and the objective lens in sequence. The production accuracy of the second mask is lower than that of the first mask.

[0008] Based on the target position, a search algorithm is used to determine the offset position of the objective lens optical axis within the second projection spot range;

[0009] The offset distance of the offset position relative to the reference position is determined, and the position of the objective lens optical axis when the second mask is used alone is determined using the offset distance.

[0010] Optionally, a sensor is used to detect the energy value of the first projection spot to determine the reference position of the objective lens optical axis within the range of the first projection spot, including: controlling the workpiece stage to move according to a first movement rule, wherein a sensor is fixedly arranged on the workpiece stage; receiving a first energy value collected by the sensor, and determining a first energy ratio value based on the first energy value, wherein the first energy value is an energy value collected by the sensor when the exposure device uses a first mask; determining whether the first energy ratio value exceeds a set threshold; if the first energy ratio value exceeds the set threshold, determining that the sensor is within the range of the first projection spot; controlling the workpiece stage to stop moving, and determining the position of the workpiece stage at this time as the first position; and determining the position of the sensor corresponding to the first position as the reference position of the objective lens optical axis.

[0011] Optionally, a sensor is used to detect the energy value of the second projection spot to determine the target position within the range of the second projection spot, including: controlling the workpiece stage to move according to a second movement rule; receiving the second energy value collected by the sensor, and determining a second energy ratio value based on the second energy value, the second energy value being the energy value collected by the sensor when the exposure device uses a second mask; determining whether the second energy ratio value exceeds a set threshold; if the second energy ratio value exceeds the set threshold, determining that the sensor is within the range of the second projection spot; controlling the workpiece stage to stop moving, and determining the position of the workpiece stage at this time as the second position; and determining the position of the sensor corresponding to the second position as the target position within the range of the second projection spot.

[0012] Optionally, the light hole of the second mask is square, and the second projection spot is a square spot; based on the target position, a search algorithm is used to determine the offset position of the objective lens optical axis within the range of the second projection spot, including: based on the target position, using a search algorithm to determine the positions of the four sides of the second projection spot; based on the positions of the four sides of the second projection spot, two diagonal lines of the second projection spot are determined; and the intersection of the two diagonal lines is determined as the offset position of the objective lens optical axis.

[0013] Optionally, based on the target position, a search algorithm is used to determine the positions of the four sides of the second projection spot, including: selecting four target path points outside the range of the second projection spot, two of the four target path points having the same horizontal coordinate as the target position in the measurement coordinate system, and the other two of the four target path points having the same vertical coordinate as the target position in the measurement coordinate system; for each target path point, a binary search algorithm is used to determine a straight line corresponding to the target path point; and the positions of four line segments obtained by the intersection of four straight lines corresponding to the four target path points are determined as the positions of the four sides of the second projection spot.

[0014] Optionally, for each target path point, a binary search algorithm is used to determine a straight line corresponding to the target path point, including: (A) determining the target path point as the path end point; (B) selecting the midpoint between the target position and the path end point as the target acquisition point; (C) controlling the movement of the workpiece stage to move the sensor to the target acquisition point; (D) receiving a preset number of second energy values ​​at the target acquisition point acquired by the sensor; (E) determining the average of the preset number of second energy values ​​as the energy average; (F) determining a straight line corresponding to the target path point based on the energy average.

[0015] Optionally, based on the energy mean, a straight line corresponding to the target path point is determined, including: based on the energy mean, a third energy ratio value is determined; whether the third energy ratio value exceeds a set threshold value; if it does not exceed the set threshold value, the midpoint between the target acquisition point and the target position is selected as the path end point, and the process returns to step (B); if it exceeds the set threshold value, interpolation processing is performed between the target acquisition point and the path end point corresponding to the target acquisition point to determine the boundary point of the second projection light spot corresponding to the target path point; a straight line passing through the boundary point and parallel to the target coordinate axis is determined, and the target coordinate axis is determined based on the positional relationship between the target path point and the target position; and a straight line parallel to the target coordinate axis is determined as a straight line corresponding to the target path point.

[0016] Optionally, the exposure device also includes a shading mechanism, which is arranged between the light source and the mask, and the second mask includes a plurality of light holes arranged in a dot matrix; before using a sensor to detect the energy value of a second projection spot emitted by the light source and passing through the central light hole of the second mask, and determining the target position within the range of the second projection spot, the method also includes: adjusting the center position of the window of the shading mechanism to be aligned with the center position of the central light hole of the second mask; adjusting the window size of the shading mechanism to be the same as the size of the central light hole of the second mask, so as to prevent the light emitted by the light source from passing through other light holes in the second mask except the central light hole.

[0017] In a second aspect, an embodiment of the present application further provides a device for determining the position of an objective lens optical axis, the device comprising:

[0018] A reference position acquisition module, used to detect the energy value of the first projection light spot by using a sensor, and determine the reference position of the optical axis of the objective lens within the range of the first projection light spot;

[0019] A target position acquisition module, used to detect the energy value of the second projection light spot using a sensor, and determine the target position within the range of the second projection light spot;

[0020] An offset position acquisition module is used to determine the offset position of the objective lens optical axis within the second projection spot range based on the target position by using a search algorithm;

[0021] The offset distance acquisition module is used to determine the offset distance of the offset position relative to the reference position, and to determine the position of the objective lens optical axis when the second mask is used alone by using the offset distance.

[0022] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate via the bus, and when the machine-readable instructions are executed by the processor, the steps of the method for determining the optical axis position of the objective lens as described above are performed.

[0023] The embodiments of the present application bring the following beneficial effects:

[0024] The embodiments of the present application provide a method, device and electronic device for determining the position of the objective lens optical axis of an exposure device. The method, device and electronic device can use sensors to respectively measure the reference position of the objective lens optical axis when the exposure device uses a first mask and the offset position of the objective lens optical axis when the exposure device uses a second mask. The accurate position of the objective lens optical axis when the second mask is used alone is determined by the reference position and the offset position. Compared with the method for determining the position of the objective lens optical axis in the prior art, the method solves the problems of cumbersome measurement process and low measurement efficiency caused by using a tooling mask for measurement each time when measuring the position of the objective lens optical axis.

[0025] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A flow chart showing a method for determining the optical axis position of an objective lens provided in an embodiment of the present application is shown;

[0028] Figure 2 A schematic diagram showing a first movement rule provided in an embodiment of the present application is shown;

[0029] Figure 3 A schematic diagram showing a second movement rule provided in an embodiment of the present application is shown;

[0030] Figure 4 A schematic diagram showing the position of a target collection point corresponding to a first target path point provided in an embodiment of the present application is shown;

[0031] Figure 5 A schematic diagram showing the structure of a device for determining the optical axis position of an objective lens provided in an embodiment of the present application is shown;

[0032] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0033] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0034] It is worth noting that before the present application was proposed, with the continuous development of semiconductor technology, the requirements for the precision of exposure equipment are getting higher and higher, and the early calibration of exposure equipment is crucial to improve the precision. Since the objective lens is in a very important position in the exposure equipment, the position calibration of the optical axis of the objective lens is also an important link to improve the precision of the exposure equipment. Before calibrating the position of the optical axis of the objective lens, it is first necessary to use hardware equipment to determine the position of the optical axis of the objective lens, and the hardware equipment includes a light source, a tooling mask, a special mask, a sensor, a shading mechanism, etc. At present, the commonly used method for measuring the optical axis position of the objective lens is to load a high-precision tooling mask in the exposure equipment, and use the position of the light beam passing through the tooling mask through the light hole and the projection spot behind the objective lens to determine the position of the optical axis of the objective lens. However, the tooling mask is expensive and the disassembly and installation process is complicated. If the position of the optical axis of the objective lens is measured by loading the tooling mask every time, not only the process is cumbersome, but also the measurement efficiency is low and the service life of the tooling mask is rapidly reduced.

[0035] Based on this, an embodiment of the present application provides a method for determining the objective lens optical axis position of an exposure device to simplify the measurement process of the objective lens optical axis and improve the measurement efficiency of the objective lens optical axis position.

[0036] First, the exposure equipment is introduced. The exposure equipment includes a light source, a shading mechanism, a mask, an objective lens and a workpiece stage. A sensor is inherently provided on the workpiece stage. The light beam emitted from the light source passes through the shading device, the mask and the objective lens in sequence, and then shines on the workpiece stage to form a projection spot.

[0037] See also Figure 1 , Figure 1 This is a flow chart of a method for determining the optical axis position of an objective lens of an exposure device provided in an embodiment of the present application. Figure 1 As shown, the method for determining the position of the objective lens optical axis of an exposure device provided in an embodiment of the present application includes:

[0038] Step S101: Detect the energy value of the first projection light spot by using a sensor to determine the reference position of the optical axis of the objective lens within the range of the first projection light spot.

[0039] In this step, the sensor may refer to a device for collecting the energy value of the light beam, and the sensor is fixed on the workpiece stage of the exposure device and can move with the workpiece stage. For example, the sensor may be a spot sensor.

[0040] Energy value may refer to the energy intensity of light, and energy value is used to determine energy ratio value.

[0041] The energy ratio value is used to determine whether the sensor is within the projection spot range. For example, when the energy ratio value is greater than 0.8, it can be considered that the sensor is within the projection spot range.

[0042] The first projection spot may refer to a projection spot formed after passing through the objective lens when the mask of the exposure device is the first mask, that is, the first projection spot is a spot formed after the light beam emitted by the light source passes through the central light hole of the first mask and the objective lens in sequence.

[0043] The first mask may refer to a high-precision tooling mask. Since the tooling mask is produced with high process precision and can be stuck in the middle of the pins of the mask table and installed in an accurate position, it is specifically used to position the optical axis of the objective lens. For example, the first mask may be a tooling mask with only one square light-transmitting hole with a side length of 2.8 mm.

[0044] The reference position may refer to the exact position of the optical axis of the objective lens, and the reference position is the position of the optical axis of the objective lens determined by a sensor when the exposure device uses the first mask.

[0045] In the embodiment of the present application, the light beam emitted by the light source of the exposure device passes through the shading mechanism, the first mask, and the objective lens in sequence, and then irradiates the workpiece stage to form a first projection light spot. At this time, the workpiece stage can be controlled to drive the sensor to move, and the sensor collects the energy value of the first projection light spot, and determines the reference position of the optical axis of the objective lens according to the collected energy value. Here, when the first mask is used, the shading mechanism is fully opened so that the light beam emitted by the light source passes through the shading mechanism.

[0046] In an optional embodiment, executing step S101 includes: controlling the workpiece stage to move according to a first movement rule, a sensor is fixedly installed on the workpiece stage; receiving a first energy value collected by the sensor, and determining a first energy ratio value based on the first energy value; determining whether the first energy ratio value exceeds a set threshold; if the first energy ratio value exceeds the set threshold, determining that the sensor is within the range of the first projection spot; controlling the workpiece stage to stop moving, and determining the position of the workpiece stage at this time as the first position; and determining the position of the sensor corresponding to the first position as the reference position of the objective lens optical axis.

[0047] Here, the first movement rule may refer to a search rule, and the first movement rule is used to determine the position of the first projection spot. As an example, the first movement rule may be a snake search rule.

[0048] The first energy value may refer to an energy value collected by a sensor when the exposure device uses a first mask, and the first energy value is used to determine a first energy ratio value.

[0049] The first energy ratio value may refer to a ratio of the first energy value to the light source energy value, and the magnitude of the first energy ratio value is used to determine whether the sensor is located within the first projection spot range.

[0050] The light source energy value may refer to the energy value at the light source, and the light source energy value may be obtained by measuring an energy sensor installed near the light source.

[0051] In an embodiment of the present application, a measurement coordinate system is first constructed, through which the positions of the workpiece stage and the sensor can be accurately recorded. The origin of the measurement coordinate system can be the center point of the workpiece stage when the workpiece stage is in the initial position. The origin of the measurement coordinate system does not move with the movement of the workpiece stage. The workpiece stage is a square. The horizontal axis of the measurement coordinate system is parallel to a set of sides of the workpiece stage, and the vertical axis of the measurement coordinate system is parallel to another set of sides of the workpiece stage. The center point of the workpiece stage is the intersection of the two diagonals of the workpiece stage. The position of the workpiece stage is represented by the center point of the workpiece stage. At the same time, the sensor is set at the center point of the workpiece stage, and the position of the workpiece stage is the position of the sensor.

[0052] Before controlling the work stage to move according to the first movement rule, the work stage is first controlled to move a first preset length in the horizontal direction from the initial position toward the first projection spot position, and the position of the work stage after moving by the first preset length is determined as the first search starting position. Here, the first preset length is preliminarily determined based on the distance between the initial position of the work stage and the position of the objective lens optical axis. Since the selected first preset length is not necessarily accurate, it is necessary to search for the reference position of the objective lens optical axis from the first search starting position.

[0053] Refer to the following Figure 2 Here we introduce the search process of the reference position of the physical optical axis.

[0054] Figure 2 A schematic diagram of a first movement rule provided in an embodiment of the present application is shown.

[0055] like Figure 2 As shown, point O is the origin of the measurement coordinate system, point 201 represents the first projection spot, point 202 is the first search starting position, and the search range 203 is selected. The search range 203 is a square with point 202 as the center point and including the first projection spot. The workpiece stage is controlled to search the lower half of the search range 203 from point 202. First, the workpiece stage is controlled to move horizontally to the right from point 202 until it moves to the right side of the search range 203, and then the workpiece stage is controlled to move vertically downward by the first search step length, and then the workpiece stage is controlled to move horizontally to the left until it moves to the left side of the search range 203, and then the workpiece stage is controlled to move vertically downward by the first search step length, and then the workpiece stage is controlled to move horizontally to the right until it moves to the right side of the search range 203. By analogy, the workpiece stage is controlled to complete the search of the lower half of the search range 203. The curve 204 in the figure is the search trajectory of the workpiece stage in the lower half of the search range 203. According to the above search process, the workpiece stage is controlled to return to point 202 to start searching the upper half of the search range 203. The curve 205 in the figure is the search trajectory of the workpiece stage in the upper half of the search range 203. The above search rule is a serpentine search rule. It can be understood that the serpentine search rule can also be to search the upper half of the search range 203 first, and then search the lower half.

[0056] Here, the first search step is determined according to the range parameter of the second projection spot. For example, if the second projection spot is a square, half of the side length of the second projection spot can be taken as the first search step.

[0057] It should be noted that the sensor moves with the workpiece stage during the entire search process, and the sensor collects the first energy value at a fixed frequency while moving, and calculates the ratio of the first energy value to the light source energy value in real time to obtain a first energy ratio value. Once the first energy ratio value exceeds the set threshold, for example: exceeds 80%, the workpiece stage is controlled to stop moving. At this time, the position of the sensor is the reference position of the objective lens optical axis.

[0058] Step S102: Utilize a sensor to detect the energy value of the second projection light spot and determine the target position within the range of the second projection light spot.

[0059] In this step, the second projection light spot is a light spot formed after the light beam emitted by the light source passes through the central light hole of the second mask and the objective lens in sequence.

[0060] The second mask may refer to a dedicated mask, and the production accuracy of the second mask is lower than the production accuracy of the first mask.

[0061] In an embodiment of the present application, the light beam emitted by the light source of the exposure device passes through the shading mechanism, the second mask, and the objective lens in sequence and then irradiates the workpiece stage to form a second projection spot. At this time, the workpiece stage can be controlled to drive the sensor to move, and the sensor collects the energy value of the second projection spot, and determines the reference position of the optical axis of the objective lens based on the collected energy value.

[0062] In an optional embodiment, executing step S102 includes: controlling the workpiece stage to move according to a second movement rule; receiving a second energy value collected by the sensor, and determining a second energy ratio value based on the second energy value; determining whether the second energy ratio value exceeds a set threshold; if the second energy ratio value exceeds the set threshold, determining that the sensor is located within the second projection spot range; controlling the workpiece stage to stop moving, and determining the position of the workpiece stage at this time as the second position; determining the position of the sensor corresponding to the second position as the target position within the second projection spot range.

[0063] Here, the second movement rule may refer to a search rule different from the first movement rule, and the second movement rule is used to determine the rough position of the second projection spot. Exemplarily, the second movement rule may be a spiral search rule.

[0064] The second energy value is an energy value collected by the sensor when the exposure device uses the second mask, and the second energy value is used to determine the second energy ratio value.

[0065] The second energy ratio value may refer to a ratio of the second energy value to the light source energy value, and the magnitude of the second energy ratio value is used to determine whether the sensor is located within the second projection spot range.

[0066] In an embodiment of the present application, before controlling the work stage to move according to the second movement rule, the work stage may also be controlled to move a second preset length in the horizontal direction from the initial position toward the second projection light spot position, and the position of the work stage after moving the second preset length is determined as the second search starting position. Here, the second preset length is preliminarily determined based on the distance between the initial position of the work stage and the position of the optical axis of the objective lens. Since the selected second preset length is not necessarily accurate, it is necessary to search for the rough position of the second projection light spot from the second search starting position. Among them, the rough position of the second projection light spot may refer to a position other than the center point of the second projection light spot.

[0067] It should be noted that the second preset length and the first preset length can be the same length or different lengths, and the second search starting position and the first search starting position can be the same position or different positions.

[0068] Refer to the following Figure 3 To introduce the search process of the target location.

[0069] Figure 3 A schematic diagram of the second movement rule provided in an embodiment of the present application is shown.

[0070] like Figure 3 As shown, point O is the origin of the measurement coordinate system, point 302 is the second search starting position, point 301 represents the second projection spot, and the workpiece stage is controlled to move horizontally to the left starting from point 302, and moves the second search step length. Then, the workpiece stage is controlled to move upward in the vertical direction by the second search step length, and then the workpiece stage is controlled to move horizontally to the right by two second search step lengths, and then the workpiece stage is controlled to move downward in the vertical direction by two second search step lengths, and then the workpiece stage is controlled to move horizontally to the left by three second search step lengths, and then the workpiece stage is controlled to move upward in the vertical direction by three second search step lengths, and so on. The workpiece stage is controlled to search according to the clockwise spiral search rule. The curve 303 in the figure is the search trajectory of the clockwise spiral search. Similarly, the spiral search can also be a counterclockwise spiral search rule.

[0071] It should be noted that during the entire spiral search process, the sensor moves with the workpiece stage, and the sensor collects the second energy value at a fixed frequency while moving, and calculates the ratio of the second energy value to the light source energy value in real time to obtain the second energy ratio value. Once the second energy ratio value exceeds the set threshold, for example: exceeds 80%, the workpiece stage is controlled to stop moving. At this time, the position of the sensor is the rough position of the second projection spot, and is also the target position within the range of the second projection spot.

[0072] Step S103: Based on the target position, a search algorithm is used to determine the offset position of the objective lens optical axis within the range of the second projection spot.

[0073] In this step, the offset position may refer to a position deviating from a reference position of the objective lens optical axis, and the offset position is used to determine a deviation between a position of the objective lens optical axis when using the second mask and a position of the objective lens optical axis when using the first mask.

[0074] In the embodiment of the present application, the center point of the second projection spot can be determined by the target position within the second projection spot, and the center point of the second projection spot is the offset position of the optical axis of the objective lens.

[0075] In an optional embodiment, the light hole of the second mask is square, and the second projection spot is a square spot; executing step S103 includes: based on the target position, using a search algorithm to determine the positions of the four sides of the second projection spot; based on the positions of the four sides of the second projection spot, determining the two diagonal lines of the second projection spot; and determining the intersection of the two diagonal lines as the offset position of the optical axis of the objective lens.

[0076] Here, when the light hole is square, the second projection spot obtained through the light hole is also square. The four sides of the second projection spot are first determined by the search algorithm. The four vertices of the second projection spot can be determined by these four sides. The two separated vertices are connected to obtain two diagonal lines. The intersection of these two diagonal lines is the center point of the second projection spot, which is also the offset position of the optical axis of the objective lens.

[0077] In an optional embodiment, based on the target position, a search algorithm is used to determine the positions of the four sides of the second projection spot, including: selecting four target path points outside the range of the second projection spot, two of the four target path points having the same horizontal coordinate as the target position in the measurement coordinate system, and the other two of the four target path points having the same vertical coordinate as the target position in the measurement coordinate system; for each target path point, a binary search algorithm is used to determine a straight line corresponding to the target path point; and the positions of four line segments obtained by the intersection of four straight lines corresponding to the four target path points are determined as the positions of the four sides of the second projection spot.

[0078] Here, the four target path points include a first target path point, a second target path point, a third target path point and a fourth target path point, wherein the first target path point and the third target path point are points outside the range of the second projection spot with the same longitudinal coordinate as the target position, and the second target path point and the fourth target path point are points outside the range of the second projection spot with the same horizontal coordinate as the target position.

[0079] In the embodiment of the present application, after determining the four target path points, a binary search algorithm is used to determine the first straight line corresponding to the first target path point, the second straight line corresponding to the second target path point, the third straight line corresponding to the third target path point, and the fourth straight line corresponding to the fourth target path point. The first straight line and the third straight line are parallel to the vertical direction of the measurement coordinate system, and the second straight line and the fourth straight line are parallel to the horizontal direction of the measurement coordinate system. The four straight lines intersect to form a square, and the four sides of the square are the four sides of the second projection light spot.

[0080] In an optional embodiment, for each target path point, a straight line corresponding to the target path point is determined using a binary search algorithm, including: (A) determining the target path point as the path end point; (B) selecting the midpoint between the target position and the path end point as the target acquisition point; (C) controlling the movement of the workpiece stage to move the sensor to the target acquisition point; (D) receiving a preset number of second energy values ​​at the target acquisition point collected by the sensor; (E) determining the average of the preset number of second energy values ​​as the energy average; (F) determining a straight line corresponding to the target path point based on the energy average.

[0081] Refer to the following Figure 4 Let's introduce the process of determining the straight line corresponding to the target path point.

[0082] Figure 4 A schematic diagram showing the positions of target collection points corresponding to the first target path point provided in an embodiment of the present application is shown.

[0083] like Figure 4 As shown, the dotted box represents the second projection spot, the target position 400 is located in the second projection spot, and outside the second projection spot there are the first target path point 401, the second target path point 402, the third target path point 403 and the fourth target path point 404. Taking the first target path point 401 as an example, the first target path point 401 is the end point of the path, and the midpoint between the target position 400 and the first target path point 401 is selected as the target acquisition point, that is, point 411 is selected as the target acquisition point, and the workpiece stage is controlled to move to point 411. Since the sensor is located at the center point of the workpiece stage, the sensor also moves to point 411. The sensor collects the second energy values ​​of the preset number at point 411, and the average of the second energy values ​​of the preset number at point 411 is used as the energy average. The straight line corresponding to the first target path point is determined according to this energy average. Those skilled in the art can select the specific value of the preset number according to actual conditions, and this application is not limited here.

[0084] In an optional embodiment, based on the energy mean, a straight line corresponding to the target path point is determined, including: based on the energy mean, determining a third energy ratio value; determining whether the third energy ratio value exceeds a set threshold; if it does not exceed the set threshold, selecting the target acquisition point as the path end point, and returning to execute step (B); if it exceeds the set threshold, interpolating between the target acquisition point and the path end point corresponding to the target acquisition point to determine the boundary point of the second projection light spot corresponding to the target path point; determining a straight line passing through the boundary point and parallel to the target coordinate axis, the target coordinate axis being determined based on the positional relationship between the target path point and the target position; and determining a straight line parallel to the target coordinate axis as a straight line corresponding to the target path point.

[0085] Here, the third energy ratio value may refer to a ratio of an energy mean value to an energy value of a light source, and the third energy ratio value is used to determine a boundary point of the second projection light spot.

[0086] The target coordinate axis is used to determine the direction of the straight line corresponding to the target path point. If the horizontal coordinates of the target path point and the target position are the same, the horizontal coordinate axis will be selected as the target coordinate axis. If the vertical coordinates of the target path point and the target position are the same, the vertical coordinate axis will be selected as the target coordinate axis.

[0087] Below is still Figure 4 The following takes the process of determining the straight line corresponding to the first target path point as an example to introduce.

[0088] The ratio of the energy mean value to the light source energy value is determined as the third energy ratio value, and whether the third energy ratio value exceeds 80% is determined. If it does not exceed 80%, point 411 is selected as the end point of the path, and the midpoint between point 411 and the target position 400 is selected as the target collection point, that is, point 421 is selected as the target collection point, and the workpiece stage is controlled to move to point 421. The sensor collects a preset number of energy values ​​at point 421, and the ratio of the mean of the preset number of energy values ​​at point 421 to the real-time collected light source energy value is used as the third energy ratio value to determine whether the third energy ratio value is If it exceeds 80%, then point 421 is selected as the end point of the path, and the midpoint between point 421 and target position 400 is selected as the target collection point, that is, point 431 is selected as the target collection point, and the workpiece stage is controlled to move to point 431. The sensor collects a preset number of energy values ​​at point 431, and the ratio of the average of the preset number of energy values ​​at point 431 to the light source energy value collected in real time is used as the third energy ratio value to determine whether the third energy ratio value exceeds 80%. If it exceeds 80%, interpolation processing is performed between point 431 and point 421. Interpolation processing refers to selecting the midpoint between the two points as the interpolation point, interpolating between point 431 and point 421, and using the interpolation point as the boundary point of the second projection light spot corresponding to the first target path point, determining a straight line passing through the boundary point and parallel to the ordinate axis, and determining the straight line as the straight line where one side of the second projection light spot is located.

[0089] In an optional embodiment, the exposure device also includes a shading mechanism, which is arranged between the light source and the mask, and the second mask includes a plurality of light holes arranged in a dot matrix; before using a sensor to detect an energy value of a second projection spot emitted by the light source and passing through a central light hole of the second mask, and determining a target position within the range of the second projection spot, the method also includes: adjusting a center position of a window of the shading mechanism to be aligned with a center position of a central light hole of the second mask; and adjusting a window size of the shading mechanism to be the same as a size of a central light hole of the second mask, so as to prevent light emitted by the light source from passing through other light holes in the second mask except the central light hole.

[0090] Here, the shading mechanism may refer to a device for blocking the light beam emitted by a light source, including four baffles on the top, bottom, left and right sides. The four baffles are driven by a motor. By adjusting the four baffles, the size, position and shape of the light-transmitting window of the shading mechanism can be adjusted.

[0091] When the second mask has 9 light holes arranged in a dot matrix or 25 light holes arranged in a dot matrix, only the central light hole of the second mask needs to be used to determine the position of the optical axis of the objective lens. In order to prevent the sensor from collecting the energy value of other light beams that have not passed through the central light hole, it is necessary to block the excess light beams. Here, a shading mechanism can be used so that only a part of the light beam emitted by the light source passes through the shading mechanism and irradiates the second mask. The purpose of the adjustment is to make the window size of the shading mechanism the same as the size of the central light hole of the second mask, the center position of the window of the shading mechanism is aligned with the center position of the central light hole of the second mask, and the shape of the window of the shading mechanism is the same as the shape of the central light hole of the second mask.

[0092] Step S104, determining an offset distance of the offset position relative to the reference position, and using the offset distance to determine the position of the optical axis of the objective lens when the second mask is used alone.

[0093] In this step, the offset distance includes a lateral offset distance and a longitudinal offset distance. The lateral offset distance may refer to the horizontal distance between the reference position of the objective lens optical axis and the offset position of the objective lens optical axis, and the longitudinal offset distance may refer to the vertical distance between the reference position of the objective lens optical axis and the offset position of the objective lens optical axis.

[0094] In the embodiment of the present application, after the reference position of the objective lens optical axis and the offset position of the objective lens optical axis are determined, the offset distance between the two positions can be calculated, that is, the difference between the horizontal coordinates of the reference position and the offset position is used as the horizontal offset distance, and the difference between the vertical coordinates of the reference position and the offset position is used as the vertical offset distance. The horizontal offset distance and the vertical offset distance jointly determine the offset distance between the reference position and the offset position. In this way, when determining the position of the objective lens optical axis, it is not necessary to use the first mask for measurement, and it is only necessary to determine the offset position through the second mask, and then determine the reference position of the objective lens optical axis through the offset position and the offset distance.

[0095] It can be seen that, through the objective lens optical axis position determination method of the present application, the reference position of the objective lens optical axis can be determined by using only the second mask, which simplifies the process of determining the objective lens optical axis position and improves measurement efficiency.

[0096] Compared with the method for determining the position of the objective lens optical axis in the prior art, the present application can use sensors to measure the reference position of the objective lens optical axis when the exposure device uses the first mask, and the offset position of the objective lens optical axis when the exposure device uses the second mask, and determine the exact position of the objective lens optical axis when the second mask is used alone through the reference position and the offset position, thereby solving the problem of cumbersome measurement process and low measurement efficiency caused by using a tooling mask for measurement each time when measuring the position of the objective lens optical axis.

[0097] Based on the same inventive concept, an embodiment of the present application also provides an objective lens optical axis position determination device for an exposure device corresponding to the objective lens optical axis position determination method for an exposure device. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the objective lens optical axis position determination method for the exposure device in the above-mentioned embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0098] See also Figure 5 , Figure 5 This is a schematic diagram of the structure of a device for determining the optical axis position of an objective lens of an exposure device provided in an embodiment of the present application. Figure 5 As shown in , the objective lens optical axis position determination device 500 of the exposure device includes:

[0099] A reference position acquisition module 501 is used to detect the energy value of the first projection light spot by using a sensor to determine the reference position of the optical axis of the objective lens within the range of the first projection light spot;

[0100] A target position acquisition module 502 is used to detect the energy value of the second projection light spot using a sensor to determine the target position within the range of the second projection light spot;

[0101] An offset position acquisition module 503 is used to determine the offset position of the objective lens optical axis within the second projection spot range based on the target position by using a search algorithm;

[0102] The offset distance acquisition module 504 is used to determine the offset distance of the offset position relative to the reference position, and use the offset distance to determine the position of the objective lens optical axis when the second mask is used alone.

[0103] Optionally, the reference position acquisition module 501 is specifically used to: control the workpiece stage to move according to a first movement rule, a sensor is fixedly arranged on the workpiece stage; receive a first energy value collected by the sensor, and determine a first energy ratio value based on the first energy value, the first energy ratio value is an energy value collected by the sensor when the exposure device uses a first mask; determine whether the first energy ratio value exceeds a set threshold; if the first energy ratio value exceeds the set threshold, determine that the sensor is within the range of the first projection spot; control the workpiece stage to stop moving, and determine the position of the workpiece stage at this time as the first position; determine the position of the sensor corresponding to the first position as the reference position of the objective lens optical axis.

[0104] Optionally, the target position acquisition module 502 is specifically used to: control the workpiece stage to move according to a second movement rule; receive a second energy value collected by the sensor, and determine a second energy ratio value based on the second energy value, the second energy value being the energy value collected by the sensor when the exposure device uses a second mask; determine whether the second energy ratio value exceeds a set threshold, and if the second energy ratio value exceeds the set threshold, determine that the sensor is located within the second projection spot range; control the workpiece stage to stop moving, and determine the position of the workpiece stage at this time as the second position; determine the position of the sensor corresponding to the second position as the target position within the second projection spot range.

[0105] Optionally, the light hole of the second mask is square, and the second projection spot is a square spot; the offset position acquisition module 503 is specifically used to: based on the target position, determine the positions of the four sides of the second projection spot using a search algorithm; based on the positions of the four sides of the second projection spot, determine the two diagonals of the second projection spot; and determine the intersection of the two diagonals as the offset position of the optical axis of the objective lens.

[0106] Optionally, the offset position acquisition module 503 is also used to: select four target path points located outside the range of the second projection spot, two of the four target path points have the same horizontal coordinate as the target position in the measurement coordinate system, and the other two of the four target path points have the same vertical coordinate as the target position in the measurement coordinate system; for each target path point, determine a straight line corresponding to the target path point using a binary search algorithm; and determine the positions of four line segments obtained by the intersection of four straight lines corresponding to the four target path points as the positions of the four sides of the second projection spot.

[0107] Optionally, the offset position acquisition module 503 is also used to: (A) determine the target path point as the path end point; (B) select the midpoint between the target position and the path end point as the target acquisition point; (C) control the movement of the workpiece stage so that the sensor moves to the target acquisition point; (D) receive a preset number of second energy values ​​at the target acquisition point collected by the sensor; (E) determine the average of the preset number of second energy values ​​as the energy average; (F) determine a straight line corresponding to the target path point based on the energy average.

[0108] Optionally, the offset position acquisition module 503 is further used to: determine a third energy ratio value based on the energy mean; determine whether the third energy ratio value exceeds a set threshold; if it does not exceed the set threshold, select the midpoint between the target acquisition point and the target position as the path end point, and return to execute step (B); if it exceeds the set threshold, perform interpolation processing between the target acquisition point and the path end point corresponding to the target acquisition point to determine the boundary point of the second projection light spot corresponding to the target path point; determine a straight line passing through the boundary point and parallel to the target coordinate axis, the target coordinate axis is determined based on the positional relationship between the target path point and the target position; and determine a straight line parallel to the target coordinate axis as a straight line corresponding to the target path point.

[0109] Optionally, the exposure device also includes a shading mechanism, which is arranged between the light source and the mask, and the second mask includes a plurality of light holes arranged in a dot matrix; the objective lens optical axis position determination device 500 of the exposure device also includes a shading module (not shown in the figure), and the shading module is used to: adjust the center position of the window of the shading mechanism to align with the center position of the central light hole of the second mask; adjust the window size of the shading mechanism to be the same as the size of the central light hole of the second mask, so as to prevent the light emitted by the light source from passing through other light holes in the second mask except the central light hole.

[0110] See also Figure 6 , Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 6 As shown in , the electronic device 600 includes a processor 610 , a memory 620 and a bus 630 .

[0111] The memory 620 stores machine-readable instructions executable by the processor 610. When the electronic device 600 is running, the processor 610 communicates with the memory 620 via the bus 630. When the machine-readable instructions are executed by the processor 610, the above-mentioned Figure 1 The steps of the method for determining the position of the objective lens optical axis of the exposure device in the method embodiment shown in the figure, and the specific implementation manner can be found in the method embodiment, which will not be repeated here.

[0112] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0113] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0114] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0115] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0116] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0117] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for determining the optical axis position of an objective lens of an exposure device, characterized in that: include: The sensor is used to detect the energy value of the first projection light spot, and the reference position of the optical axis of the objective lens within the range of the first projection light spot is determined, wherein the first projection light spot is a light spot formed after the light beam emitted by the light source passes through the central light hole of the first mask and the objective lens in sequence; The sensor is used to detect the energy value of the second projection spot, and the target position within the second projection spot is determined, wherein the second projection spot is a spot formed after the light beam emitted by the light source passes through the central light hole of the second mask and the objective lens in sequence, and the production accuracy of the second mask is lower than that of the first mask; Based on the target position, a search algorithm is used to determine the offset position of the objective lens optical axis within the second projection spot range; An offset distance of the offset position relative to the reference position is determined, and the position of the optical axis of the objective lens when the second mask is used alone is determined using the offset distance.

2. The method according to claim 1, characterized in that The method of detecting the energy value of the first projection light spot by using a sensor to determine the reference position of the optical axis of the objective lens within the range of the first projection light spot comprises: Controlling the workpiece platform to move according to a first movement rule, wherein a sensor is fixedly arranged on the workpiece platform; receiving a first energy value collected by a sensor, and determining a first energy ratio value based on the first energy value, wherein the first energy value is an energy value collected by the sensor when the exposure device uses a first mask; determining whether the first energy ratio value exceeds a set threshold; If the first energy ratio value exceeds a set threshold, it is determined that the sensor is within the range of the first projection spot; Controlling the workpiece stage to stop moving, and determining the position of the workpiece stage at this time as the first position; The position of the sensor corresponding to the first position is determined as the reference position of the objective lens optical axis.

3. The method according to claim 1, characterized in that The method of detecting the energy value of the second projection light spot by using a sensor to determine the target position within the range of the second projection light spot includes: Controlling the workpiece table to move according to the second moving rule; receiving a second energy value collected by the sensor, and determining a second energy ratio value based on the second energy value, wherein the second energy value is an energy value collected by the sensor when the exposure device uses a second mask; determining whether the second energy ratio value exceeds a set threshold; If the second energy ratio value exceeds a set threshold, it is determined that the sensor is located within the second projection spot range; Controlling the workpiece stage to stop moving, and determining the position of the workpiece stage at this time as a second position; The position of the sensor corresponding to the second position is determined as the target position within the range of the second projection spot.

4. The method according to claim 1, characterized in that The light hole of the second mask is square, and the second projection spot is a square spot; The method of determining the offset position of the objective lens optical axis within the second projection spot range by using a search algorithm based on the target position includes: Based on the target position, using a search algorithm to determine the positions of the four sides of the second projection spot; Determine two diagonal lines of the second projection light spot based on the positions of the four sides of the second projection light spot; The intersection of the two diagonal lines is determined as the offset position of the objective lens optical axis.

5. The method according to claim 4, characterized in that The method of determining the positions of the four sides of the second projection light spot based on the target position by using a search algorithm comprises: Selecting four target path points outside the range of the second projection spot, two of the four target path points having the same horizontal coordinate as the target position in the measurement coordinate system, and the other two of the four target path points having the same vertical coordinate as the target position in the measurement coordinate system; For each target path point, a binary search algorithm is used to determine a straight line corresponding to the target path point; The positions of four line segments obtained by intersecting four straight lines corresponding to the four target path points are determined as the positions of the four sides of the second projection light spot.

6. The method according to claim 5, characterized in that The method of determining a straight line corresponding to each target path point by using a binary search algorithm includes: (A) determining the target path point as the path end point; (B) Select the midpoint between the target position and the end point of the path as the target collection point; (C) controlling the workpiece stage to move so that the sensor moves to the target acquisition point; (D) receiving a preset number of second energy values ​​at the target collection points collected by the sensor; (E) determining an average of the preset number of second energy values ​​as an energy average; (F) Based on the energy mean, determine a straight line corresponding to the target path point.

7. The method according to claim 6, characterized in that The step of determining a straight line corresponding to the target path point based on the energy mean value includes: Based on the energy mean, determining a third energy ratio value; determining whether the third energy ratio value exceeds a set threshold; If it does not exceed the set threshold, the target collection point is selected as the path end point and the process returns to step (B); If it exceeds the set threshold, interpolation processing is performed between the target acquisition point and the path end point corresponding to the target acquisition point to determine the boundary point of the second projection light spot corresponding to the target path point; Determine a straight line passing through the boundary point and parallel to a target coordinate axis, wherein the target coordinate axis is determined based on a positional relationship between the target path point and the target position; The straight line parallel to the target coordinate axis is determined as a straight line corresponding to the target path point.

8. The method according to claim 1, characterized in that: The exposure device further comprises a shading mechanism, which is arranged between the light source and the mask, and the second mask comprises a plurality of light holes arranged in a dot matrix; Before using the sensor to detect the energy value of the second projection light spot emitted by the light source and passing through the central light hole of the second mask to determine the target position within the range of the second projection light spot, the method further includes: Adjusting the center position of the window of the shading mechanism to be aligned with the center position of the central light hole of the second mask; The window size of the shading mechanism is adjusted to be the same as the size of the central light hole of the second mask, so as to prevent the light emitted by the light source from passing through other light holes in the second mask except the central light hole.

9. A device for determining the position of an objective lens optical axis of an exposure device, characterized in that: include: A reference position acquisition module, used to detect the energy value of the first projection light spot by using a sensor, and determine the reference position of the optical axis of the objective lens within the range of the first projection light spot; A target position acquisition module, used to detect the energy value of the second projection light spot using a sensor, and determine the target position within the range of the second projection light spot; An offset position acquisition module, used to determine the offset position of the objective lens optical axis within the second projection spot range based on the target position by using a search algorithm; The offset distance acquisition module is used to determine the offset distance of the offset position relative to the reference position, and use the offset distance to determine the position of the objective lens optical axis when the second mask is used alone.

10. An electronic device, characterized in that: include: A processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the storage medium via the bus, and the processor executes the machine-readable instructions to perform the steps of the method for determining the optical axis position of an objective lens as described in any one of claims 1 to 8.

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