Laser positioning device and wafer inspection system

Abstract

This disclosure presents a laser positioning device and a wafer inspection system. The laser positioning device includes a stage, an orthogonal test feedback element, and an optical path element. The stage includes a moving mechanism, a support member, and a measuring mirror. The moving mechanism drives the support member to move in a first direction and a second direction. The measuring mirror is mounted on the support member, with a first measuring surface intersecting the first direction and a second measuring surface intersecting the second direction. The orthogonal test feedback element has a first measuring head and a second measuring head. The first measuring head emits a first laser beam along the first direction toward the first measuring surface, and the second measuring head emits a second laser beam. The optical path element splits the second laser beam into multiple third laser beams and directs them toward the second measuring surface along the second direction. High-precision positioning at multiple points can be achieved through the first laser beam and the multiple third laser beams.

Description

Technical Field

[0001] This disclosure belongs to the field of semiconductor technology, and in particular relates to a laser positioning device and a wafer inspection system. Prior Technology

[0002] With the development of semiconductor technology, higher requirements are placed on semiconductor equipment. When inspecting or performing other operations on wafers, it is necessary to accurately position the stage that carries the wafers, thereby improving the measurement accuracy and defect detection rate in advanced processes.

[0003] In related technologies, a super-large stage carries the wafer, and the stage can move the wafer to meet the displacement requirements of wafer inspection. The stage is positioned using a grating ruler; however, when positioning the wafer using the grating ruler, the distance between the grating ruler and the wafer is large, resulting in Abbe error in the measurement. Summary of the Invention

[0004] This disclosure provides a laser positioning device and a wafer inspection system, which can improve positioning accuracy.

[0005] In a first aspect, this disclosed embodiment provides a laser positioning device, which includes a stage, an orthogonality test feedback element, and an optical path element; the stage includes a moving mechanism, a carrier, and a measuring mirror, the moving mechanism is used to drive the carrier to move in a first direction and a second direction, the measuring mirror is mounted on the carrier, the first measuring surface of the measuring mirror intersects the first direction, and the second measuring surface of the measuring mirror intersects the second direction; the orthogonality test feedback element is provided with a first measuring head and a second measuring head, the first measuring head emits a first laser beam toward the first measuring surface along the first direction, and the second measuring head emits a second laser beam; the optical path element is used to divide the second laser beam into multiple third laser beams and direct them toward the second measuring surface along the second direction.

[0006] Optionally, the optical path element includes a beam splitter and a reflector; the beam splitter is located in the optical path of the second laser beam and is used to split the second laser beam into a first reflected laser beam and a third laser beam; the reflector is located in the optical path of the first reflected laser beam and is used to reflect the first reflected laser beam into another third laser beam.

[0007] Optionally, the beam splitting component includes a first beam splitter, one side of which contains the second laser beam and the first reflected laser beam, and the other side of which contains the third laser beam; the reflecting component includes a reflector, one side of which contains the first reflected laser beam and the third laser beam.

[0008] Optionally, the beam splitter further includes a second beam splitter located between the first beam splitter and the reflector, for transmitting the first reflected beam and forming a third laser beam.

[0009] Optionally, the angle between the first reflected laser beam and the second laser beam is 90°; the angle between the first reflected laser beam and the third laser beam is 90°.

[0010] Optionally, the transmission-to-reflection ratio of the first beam splitter is 1:2, and the transmission-to-reflection ratio of the second beam splitter is 1:1.

[0011] Optionally, the carrier includes a mounting plate and a suction cup; the mounting plate is mounted on the moving mechanism, and the suction cup is mounted on the mounting plate; the measuring mirror is mounted on the mounting plate, the height of the measuring mirror is lower than the height of the suction cup, the first measuring surface of the measuring mirror is perpendicular to the first direction, the second measuring surface of the measuring mirror is perpendicular to the second direction, and the first measuring surface is perpendicular to the second measuring surface.

[0012] Optionally, the moving mechanism includes a first moving mechanism and a second moving mechanism; the first moving mechanism is provided with a first grating ruler, the first moving mechanism is used to move in the first direction, and the first grating ruler is used to provide operation control for the first moving mechanism; the second moving mechanism is mounted on the first moving mechanism, the second moving mechanism is provided with a second grating ruler, the second moving mechanism is used to move in the second direction, and the second grating ruler is used to provide operation control for the second moving mechanism.

[0013] Secondly, this disclosure provides a wafer inspection system, which includes a main body and a laser positioning device; the main body is provided with a plurality of inspection heads, which are located above the stage and are used to inspect the wafers on the stage, and the inspection points of the plurality of inspection heads are respectively located at the intersection of the first laser beam path and the third laser beam path.

[0014] Optionally, the detection head includes a first detection head, a second detection head, and a third detection head; the first detection head is an electro-optical detection head, the second detection head is a geometrical optical detection head, and the third detection head is a deep ultraviolet geometrical optical detection head.

[0015] This disclosure provides a laser positioning device and a wafer inspection system. The laser positioning device includes a stage, an orthogonal test feedback element, and an optical path element. The stage can move the wafer in a first direction and a second direction. A measuring mirror is mounted on the stage and can provide a positioning reference for the orthogonal test feedback element. The first measuring head of the orthogonal test feedback element emits a first laser beam toward a first measuring surface. The second laser beam emitted by the second measuring head is split into multiple third laser beams by the optical path element and directed toward a second measuring surface. This allows for precise positioning of the first laser beam and the multiple third laser beams at the intersection of the optical paths, improving positioning accuracy and reducing Abbe error in the measurement.

[0016] This disclosure provides a method, apparatus, medium, and product for determining mask patterns, which can correct etching deviations in curve patterns and thus efficiently complete the design of mask patterns.

[0017] On the one hand, this disclosure provides a method for determining a mask pattern, including:

[0018] A first target etching pattern and a plurality of first sampling points for characterizing the pattern contour of the first target etching pattern are obtained; the pattern contour includes a curve contour.

[0019] Optical proximity correction is applied to the first target etching pattern to obtain the first mask pattern;

[0020] The first mask pattern is subjected to photolithography simulation to obtain a first photolithography pattern, and the first mask pattern is subjected to photolithography etching simulation to obtain a first etched pattern;

[0021] For each of the first sampling points, the first etching deviation data at the corresponding positions of the first sampling points on the first lithographic pattern and the first etched pattern are determined respectively;

[0022] For each of the first sampling points, based on the first etching deviation data, the etching deviation of the first sampling point is corrected to obtain multiple second sampling points;

[0023] Based on the multiple second sampling points, the target mask pattern is determined.

[0024] On the other hand, based on the plurality of second sampling points, the target mask pattern is determined, including:

[0025] Based on the multiple second sampling points, a target lithographic pattern is generated;

[0026] The target lithographic pattern is corrected for optical proximity effect to obtain a second mask pattern;

[0027] A photolithography simulation is performed on the second mask pattern to obtain a second photolithography pattern, and a photolithography etching simulation is performed on the second mask pattern to obtain a second etched pattern;

[0028] For each second sampling point, second etching deviation data at the corresponding position of the second sampling point on the second lithographic pattern and the second etched pattern are determined respectively;

[0029] If the second etching deviation data does not meet the preset conditions, the etching deviation of the first sampling point is corrected based on the second etching deviation data to obtain the third sampling point;

[0030] The process involves replacing multiple second sampling points with the third sampling point and returning to the step of generating the target lithography pattern based on the multiple second sampling points; this continues until the second etching deviation data meets the preset conditions.

[0031] If the second etching deviation data meets the preset conditions, the current second mask pattern is determined as the target mask pattern.

[0032] On the other hand, based on the plurality of second sampling points, the target mask pattern is determined, including:

[0033] Based on the multiple second sampling points, a target lithographic pattern is generated;

[0034] Optical proximity correction is applied to the target lithographic pattern to obtain the target mask pattern.

[0035] On the other hand, optical proximity correction is applied to the first target etching pattern to obtain a first mask pattern, including:

[0036] The first target etched pattern is Manhattanized to obtain the corresponding Manhattan pattern;

[0037] The Manhattan pattern is corrected for optical proximity effect to obtain the first mask pattern.

[0038] On the other hand, the graphic contour also includes a straight line contour;

[0039] Acquiring the plurality of first sampling points used to characterize the pattern contour of the first target etched pattern includes:

[0040] For the straight line contour in the first target etched pattern, at least one point on the straight line is obtained as a feature point;

[0041] For the curve contour in the first target etched pattern, curve contour points are acquired at preset intervals;

[0042] The feature points and the curve contour points are determined as the first sampling points.

[0043] On the other hand, for each of the first sampling points, the first etching deviation data at the corresponding position on the first lithographic pattern and the first etched pattern at the first sampling point is determined, including:

[0044] For each of the first sampling points, the offset distance and offset direction at the corresponding positions on the first lithographic pattern and the first etched pattern are determined respectively;

[0045] Correspondingly, for each of the first sampling points, based on the first etching deviation data, etching deviation correction is performed on the first sampling point to obtain multiple second sampling points, including:

[0046] Each of the first sampling points is moved by the corresponding offset distance in the opposite direction of its respective offset direction to obtain a plurality of second sampling points.

[0047] On the other hand, obtaining the first photolithographic pattern after photolithographic simulation of the first mask pattern, and obtaining the first etched pattern after photolithographic simulation and etching simulation, includes:

[0048] The first mask pattern is input into the photolithography simulation model to obtain the first photolithography pattern;

[0049] The first photolithographic pattern is input into the etching simulation model to obtain the first etched pattern.

[0050] On the other hand, the etching simulation model includes a fusion unit, a neural network unit, and at least one physical effect analog unit;

[0051] The first photolithographic pattern is input into the etching simulation model to obtain the first etched pattern, including:

[0052] The first lithographic pattern is input into the at least one physical effect analogy unit to obtain at least one first sub-image, and the first lithographic pattern is input into the neural network unit to obtain a second sub-image; the neural network unit is trained based on lithographic pattern samples and corresponding etching image labels.

[0053] The first etched pattern is obtained by fusing the at least one first sub-image and the second sub-image based on the fusion unit.

[0054] In another aspect, this disclosure provides a mask pattern determination device, including: a processor and a memory storing computer program instructions;

[0055] When the processor executes the computer program instructions, it implements the mask pattern determination method described above.

[0056] In another aspect, this disclosure provides a computer-readable storage medium storing computer program instructions, which, when executed by a processor, implement the mask pattern determination method described above.

[0057] In another aspect, this disclosure provides a computer program product in which instructions, when executed by a processor of an electronic device, cause the electronic device to perform the mask pattern determination method as described above.

[0058] The mask pattern determination method disclosed in this embodiment determines the target mask pattern based on multiple second sampling points. These second sampling points are obtained by correcting the etching deviation of the first sampling points based on the first etching deviation data between the first lithographic pattern and the first etched pattern at the corresponding positions. Since the first sampling point can characterize the outline of the first target etched pattern, this disclosure, by correcting multiple sampling points separately, can accurately correct the etching deviation of the curve outline. Therefore, this embodiment can efficiently complete the design of the mask pattern corresponding to the curve pattern. Simple Explanation of the Diagram

[0059] To more clearly illustrate the technical solutions of the embodiments disclosed herein, the accompanying drawings used in the embodiments disclosed herein will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 is a schematic diagram of the structure of a laser positioning device according to some embodiments of this disclosure from one view. Figure 2 is a structural schematic diagram of the laser positioning device according to some embodiments of this disclosure from another perspective; Figure 3 is a schematic diagram of the structure of optical path elements in some embodiments of this disclosure; Figure 4 is a schematic diagram of the structure of optical path elements in some other embodiments of this disclosure. Implementation

[0060] The features and exemplary embodiments of various aspects of this disclosure will now be described in detail. To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description, in conjunction with the accompanying drawings and specific embodiments, will provide a further detailed description. It should be understood that the specific embodiments described herein are intended only to explain this disclosure and not to limit it. For those skilled in the art, this disclosure can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this disclosure by illustrating examples.

[0061] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0062] With the development of semiconductor technology and the advancement of process technology, the linewidth of integrated circuits is becoming increasingly smaller, which places higher and more difficult demands on the circuit manufacturing process technology. At the same time, in order to reduce costs, increase efficiency, improve production efficiency, and increase the utilization rate of cleanrooms, semiconductor foundries are placing higher demands on semiconductor equipment.

[0063] When optical inspection, exposure, and other equipment inspect or perform other operations on wafers, it is necessary to achieve full-range positioning and measurement of the stage supporting the wafers, thereby improving the measurement accuracy and defect detection rate in advanced processes. During wafer inspection, inspection equipment typically integrates multiple inspection modes, inspecting wafers on the same stage under various modes. Each inspection mode corresponds to a specific inspection head, and each inspection head has a certain volume. In the assembly design, to avoid interference when multiple inspection heads are installed, adjacent inspection heads are spaced apart; furthermore, the stage's bearing surface has a certain size (e.g., a 300mm × 300mm square bearing surface), thus allowing the inspection points of multiple inspection heads to be distributed in different positions, forming multiple inspection points.

[0064] In related technologies, the stage includes an X-axis moving mechanism and a Y-axis moving mechanism, and positioning is achieved by controlling the displacement of the X-axis and Y-axis moving mechanisms using a grating ruler. However, when positioning multiple detection points on a wafer, the grating ruler is far from the wafer, resulting in Abbe error in the measurement. Therefore, this disclosure provides a laser positioning device and a wafer inspection system.

[0065] Please refer to Figures 1 to 4. Figure 1 is a structural schematic diagram of a laser positioning device according to some embodiments of the present disclosure from one view; Figure 2 is a structural schematic diagram of a laser positioning device according to some embodiments of the present disclosure from another view; Figure 3 is a structural schematic diagram of an optical path element according to some embodiments of the present disclosure; and Figure 4 is a structural schematic diagram of an optical path element according to other embodiments of the present disclosure.

[0066] In a first aspect, as shown in Figures 1 and 2, this disclosed embodiment provides a laser positioning device, which includes a stage 1, an orthogonality test feedback element 2, and an optical path element 3. The stage 1 includes a moving mechanism 11, a support member 12, and a measuring mirror 13. The support member 12 is mounted on the moving mechanism 11, which drives the support member 12 to move in a first direction X and a second direction Y. The measuring mirror 13 is mounted on the support member 12, with its first measuring surface 131 intersecting the first direction X and its second measuring surface 132 intersecting the second direction Y. The orthogonality test feedback element 2 has a first measuring head 21 and a second measuring head 22. The first measuring head 21 emits a first laser beam 5 along the first direction X toward the first measuring surface 131, and the second measuring head 22 emits a second laser beam 6. The optical path element 3 receives the second laser beam 6 emitted by the second measuring head 22 and divides it into multiple third laser beams 7, which are then directed along the second direction Y toward the second measuring surface 132.

[0067] The stage 1 moves in the first direction X and the second direction Y via the moving mechanism 11. The first direction X intersects the second direction Y (for example, the first direction X can be perpendicular to the second direction Y), thereby enabling the carrier 12 to move in the plane. The carrier 12 is mounted on the moving mechanism 11 and serves as a carrier for the workpiece (e.g., wafer 4). The measuring mirror 13 is mounted on the carrier 12 and receives the first laser beam 5 through the first measuring surface 131 and the third laser beam 7 through the second measuring surface 132, providing positioning references for the first laser beam 5 and the third laser beam 7.

[0068] The orthogonality test feedback element 2 may include an orthogonality test feedback body 23, a first measuring head 21, and a second measuring head 22. Each orthogonality test feedback body 23 is connected to a first measuring head 21 and a second measuring head 22. The first measuring head 21 and the second measuring head 22 can cooperate with the orthogonality test feedback body 23 to achieve distance measurement. For example, a first laser beam 5 emitted by the first measuring head 21 reaches the first measuring surface 131 and returns; a second laser beam 6 emitted by the second measuring head 22 reaches the second measuring surface 132 and returns along the same path. The returning laser beams form an interference pattern within the orthogonality test feedback body 23. When the position of the stage 1 changes, the optical path difference between the first laser beam 5 and the second laser beam 6 changes, causing a change in the interference pattern. The orthogonality test feedback body 23 can calculate the displacement of the stage 1 by monitoring and analysis. The orthogonality test feedback element 2 may employ a laser interferometer.

[0069] Each orthogonality test feedback element 2 has only one first measuring head 21 and one second measuring head 22. The first measuring head 21 and the second measuring head 22 emit laser beams to directly achieve planar positioning of a single detection point, which cannot meet the requirements for positioning multiple detection points. To address this, the first measuring head 21 emits a first laser beam 5 along the first direction X toward the first measuring surface 131, enabling precise positioning of multiple detection points along the first direction X. The second measuring head 22 emits a second laser beam 6, which is directed toward the optical path element 3. The optical path element 3 can split the second laser beam 6 into multiple third laser beams 7, and direct these multiple third laser beams 7 along the second direction Y toward the second measuring surface 132, enabling precise positioning of multiple detection points along the second direction Y. A single first laser beam 5 and multiple third laser beams 7 can form multiple intersection points on the optical path, thus achieving full-area positioning of multiple detection points. Both the first laser beam 5 and the third laser beams 7 are located on the straight line of the detection point positioning direction, thereby reducing Abbe error.

[0070] Optical path element 3 receives the second laser beam 6 and splits the second laser beam 6 into multiple third laser beams 7. The multiple third laser beams 7 and a first laser beam 5 can form multiple intersection points on the optical path, and the number of intersection points is the same as the number of third laser beams 7.

[0071] In the technical solution of the above embodiment, the laser beam positioning device includes a stage 1, an orthogonality test feedback element 2, and an optical path element 3. The stage 1 serves as a support and positioning reference. The orthogonality test feedback element 2 and the optical path element 3 can form a first laser beam 5 and multiple third laser beams 7. The first laser beam 5 and the multiple third laser beams 7 form multiple intersection points on the optical path, and each intersection point corresponds to a detection point, thereby enabling the positioning of multiple detection points. The first laser beam 5 and the third laser beams 7 are both located on a straight line in the positioning direction of the detection point, thereby reducing the Abbe error during measurement, improving positioning accuracy, and providing precise positioning for multiple detection points.

[0072] In some embodiments, as shown in FIG3, the optical path element 3 includes a beam splitter 31 and a reflector 32. The beam splitter 31 is located in the optical path of the second laser beam 6 and is used to split the second laser beam 6 into a first reflected laser beam 8 and a third laser beam 7. The reflector 32 is located in the optical path of the first reflected laser beam 8 and is used to reflect the first reflected laser beam 8 into another third laser beam 7.

[0073] The beam splitter 31 is located in the optical path of the second laser beam 6, and the reflector 32 is located in the optical path of the first reflected laser beam formed by the specular reflection of the second laser beam 6 on the beam splitter 31. The second laser beam 6 illuminates the beam splitter 31, which can split the second laser beam 6 into two beams: a first reflected laser beam 8 and a third laser beam 7. The first reflected laser beam 8 illuminates the reflector 32, which can change the transmission direction of the first reflected laser beam 8, resulting in a third laser beam 7.

[0074] The beam splitter 31 and the reflector 32 work together to split a second laser beam 6 into two third laser beams 7. For example, the beam splitter 31 can be a beam splitter mirror, and the reflector 32 can be a reflector mirror 321. The beam splitter mirror realizes the change in the number of laser beams and the change in the propagation path, and the reflector mirror 321 realizes the change in the propagation path of the laser beams.

[0075] In the above embodiment, the beam splitting element 31 and the reflecting element 32 can split a second laser beam 6 into two third laser beams 7, and the two third laser beams 7 illuminate the second measuring surface 132 along the second direction Y. The two third laser beams 7 and a first laser beam 5 can form two intersection points in the optical path, thereby providing accurate positioning for the two detection points.

[0076] In some embodiments, as shown in FIG3, the beam splitting assembly 31 includes a first beam splitter 311, one side of which is a second laser beam 6 and a first reflected laser beam 8, and the other side of which is a third laser beam 7. The reflecting assembly 32 includes a reflector 321, one side of which is the first reflected laser beam 8 and the third laser beam 7.

[0077] The second laser beam 6 illuminates the first beam splitter 311, which transmits and reflects the second laser beam 6. After transmission, a third laser beam 7 is formed, and after reflection, a first reflected laser beam 8 is formed. The first reflected laser beam 8 is directed towards the reflector 321, which performs mirror reflection on the first reflected laser beam, changing its propagation path to form another third laser beam 7.

[0078] In the above embodiment, the second laser beam 6 and the first reflected laser beam 8 are located on the same side of the first beam splitter 311. The mirror reflection facilitates the determination of the optical path, thereby making it convenient to arrange the position and angle of the reflector 321.

[0079] In some embodiments, as shown in FIG4, the beam splitter 31 further includes a second beam splitter 312, which is located between the first beam splitter 311 and the reflector 321, and is used to transmit the first reflected beam and form a third laser beam 7.

[0080] The second beam splitter 312 is located in the optical path of the first reflected laser beam 8. The first reflected laser beam 8 is directed toward the second beam splitter 312. The second beam splitter 312 transmits a portion of the first reflected beam onto the reflector 321 and reflects the other portion of the first beam, changing the propagation path to become the third laser beam 7.

[0081] The third laser beam 7 formed at the first beam splitter 311 is formed by transmission from the first beam splitter 311; the third laser beam 7 formed at the second beam splitter 312 is formed by reflection from the second beam splitter 312; and the third laser beam 7 formed at the reflector 321 is formed by reflection from the reflector 321.

[0082] In the above embodiment, the optical path element 3 includes a first beam splitter 311, a second beam splitter 312, and a reflector 321. After the second laser beam 6 is directed toward the optical path element 3, it can form three third laser beams 7. The three third laser beams 7 and one first laser beam 5 can form three intersection points on the optical path, thereby enabling precise positioning of the three detection points.

[0083] In some embodiments, as shown in FIG4, the angle between the first reflected laser beam 8 and the second laser beam 6 is 90°; the angle between the first reflected laser beam 8 and the third laser beam 7 is 90°.

[0084] The first reflected laser beam 8 and the second laser beam 6 are arranged perpendicularly. The first beam splitter 311 is a 90° beam splitter, which can split the incident light at a 90° angle (the second laser beam 6 is split into a third laser beam 7 and a first reflected laser beam 8 at a 90° angle). The first reflected laser beam 8 and the third laser beam 7 are arranged perpendicularly. The second beam splitter 312 is a 90° beam splitter, which can split the incident light at a 90° angle (the first reflected laser beam 8 is split into a third laser beam 7).

[0085] In the above embodiment, the first reflected laser beam 8 is perpendicular to the second laser beam 6 and the third laser beam 7 respectively. The second laser beam 6 and the third laser beam 7 are perpendicular to each other, which facilitates the control of the optical path of the laser beam. The arrangement of the first beam splitter 311, the second beam splitter 312 and the third beam splitter is more convenient.

[0086] In some embodiments, as shown in FIG4, the transmission-to-reflection ratio of the first beam splitter 311 is 1:2, and the transmission-to-reflection ratio of the second beam splitter 312 is 1:1.

[0087] When facing the incident light beam, the first beam splitter 311 transmits one-third of the incident light beam intensity and reflects two-thirds, while the second beam splitter 312 transmits half of the incident light beam intensity and reflects half. When the second laser beam 6 is directed towards the first beam splitter 311, it is transmitted through the first beam splitter 311 to form a first third laser beam 7 and reflected to form a first reflected laser beam 8. The intensity of the third laser beam 7 is one-third of the intensity of the second laser beam 6, and the intensity of the first reflected laser beam 8 is two-thirds of the intensity of the second laser beam 6. The first reflected laser beam 8 is directed towards the second beam splitter 312 and reflected at the second beam splitter 312 to form a second third laser beam 7. The intensity of the third laser beam 7 is half of the intensity of the first reflected laser beam 8. The remaining half of the intensity of the first reflected laser beam 8 is reflected by the mirror 321 after passing through the second beam splitter 312 to form the third third laser beam 7.

[0088] In the above embodiment, the transmission-to-reflection ratio of the first beam splitter 311 is 1:2, the transmission-to-reflection ratio of the second beam splitter 312 is 1:1, and the three third laser beams 7 formed by the second laser beam 6 through the first beam splitter 311, the second beam splitter 312, and the reflector 321 have equal light intensity, which can improve the positioning accuracy.

[0089] In some embodiments, as shown in Figures 1 and 2, the carrier 12 includes a mounting plate and a suction cup. The mounting plate is mounted on the moving mechanism 11, and the suction cup is mounted on the mounting plate. The measuring mirror 13 is also mounted on the mounting plate, and the height of the measuring mirror 13 is lower than the height of the suction cup. The first measuring surface 131 of the measuring mirror 13 is perpendicular to the first direction X, and the second measuring surface 132 of the measuring mirror 13 is perpendicular to the second direction Y. The first measuring surface 131 and the second measuring surface 132 are perpendicular to each other.

[0090] The mounting plate is installed on the moving mechanism 11, providing mounting positions for the suction cup and measuring mirror 13. The suction cup, mounted on the mounting plate, can adsorb and fix the wafer 4 onto the suction cup. The measuring mirror 13, mounted on the mounting plate, can be spaced apart from the suction cup or attached to it. When the suction cup is mounted on the mounting plate, the distance between the bearing surface of the suction cup and the mounting plate is H1; when the measuring mirror 13 is mounted on the mounting plate, the distance between the top surface of the measuring mirror and the mounting plate is H2, where H1 > H2.

[0091] The measuring mirror 13 can be a one-piece structure or a split structure. For example, when the measuring mirror 13 is a one-piece structure, it can be divided into two mutually perpendicular parts. A first measuring surface 131 is located on the first part, and a second measuring surface 132 is located on the second part. One end of the first part is connected to one end of the second part, and the first part is perpendicular to the second part. When the measuring mirror 13 is a split structure, it can include a first measuring mirror and a second measuring mirror. The first measuring surface 131 is located on the first measuring mirror, and the second measuring surface 132 is located on the second measuring mirror. The first measuring mirror is perpendicular to the second measuring mirror.

[0092] In the above embodiment, the first measuring surface 131 of the measuring mirror 13 is perpendicular to the first direction X, and thus the first measuring surface 131 is perpendicular to the first laser beam 5; the second measuring surface 132 of the measuring mirror 13 is perpendicular to the second direction Y, and thus the second measuring surface 132 is perpendicular to the third laser beam 7, which can improve positioning accuracy. The height of the measuring mirror 13 is lower than the height of the suction cup, which can avoid contact with the wafer 4 and prevent the wafer 4 from being bumped.

[0093] In some embodiments, as shown in Figures 1 and 2, the moving mechanism 11 includes a first moving mechanism 112 and a second moving mechanism 111. The first moving mechanism 112 is provided with a first grating ruler 1121, and the first moving mechanism 112 is used to move in a first direction X. The first grating ruler 1121 is used to provide operational control for the first moving mechanism 112. The second moving mechanism 111 is mounted on the first moving mechanism 112, and the second moving mechanism 111 is provided with a second grating ruler 1111, and the second moving mechanism 111 is used to move in a second direction Y. The second grating ruler 1111 is used to provide operational control for the second moving mechanism 111.

[0094] The first moving mechanism 112 translates in the first direction X, and the second moving mechanism 111 translates in the second direction Y. The first direction X and the second direction Y are perpendicular, enabling the moving mechanism 11 to translate within a plane. The first grating ruler 1121 can be connected to a host computer to control the moving distance of the first moving mechanism 112; the second grating ruler 1111 can be connected to a host computer to control the moving distance of the second moving mechanism 111.

[0095] The first laser beam 5 is perpendicular to the first measuring surface 131, and the third laser beam 7 is perpendicular to the second measuring surface 132. The first measuring surface 131 is perpendicular to the second measuring surface 132, and a rectangular coordinate system can be established for positioning.

[0096] In the technical solution of the above embodiment, the moving mechanism 11 can achieve independent control of translation in the first direction X and the second direction Y by setting the first moving mechanism 112 and the second moving mechanism 111, and the displacement of the suction cup can be controlled by the first grating ruler 1121 and the second grating ruler 1111, thereby improving the displacement accuracy of the suction cup.

[0097] Secondly, as shown in Figure 2, this disclosed embodiment provides a wafer inspection system, which includes a main body 9 and the laser positioning device provided in the above-mentioned technical solution. The main body 9 is equipped with multiple inspection heads located above the stage 1 for inspecting the wafers 4 on the stage 1. The inspection points of the multiple inspection heads are respectively located at the intersection of the optical paths of the first laser beam 5 and the third laser beam 7.

[0098] The main body 9 of the equipment is the component that mainly performs the inspection function of the wafer 4 inspection system, and also provides the mounting base for the laser positioning device. The inspection head serves as the port for inspecting wafer 4 in the main body 9 of the equipment. During inspection, the inspection point coincides with the intersection of the optical paths of the first laser beam 5 and the third laser beam 7.

[0099] In the technical solution of the above embodiment, the intersection of the optical path of the first laser beam 5 and the optical path of the third laser beam 7, thereby enabling the laser positioning device to provide accurate positioning for multiple detection points and reduce the Abbe error present during wafer 4 detection.

[0100] In some embodiments, as shown in FIG2, the detection head includes a first detection head 91, a second detection head 92, and a third detection head 93; the first detection head 91 is an electro-optical detection head, the second detection head 92 is a geometrical optical detection head, and the third detection head 93 is a deep ultraviolet geometrical optical detection head.

[0101] On the main body 9 of the device, multiple detection heads are not located in one place in space, but rather there is a center distance deviation between adjacent detection heads. Multiple detection points of multiple detection heads are located on a straight line, and this straight line coincides with the optical path of the first laser beam 5. The first laser beam 5 can provide positioning for multiple detection points in the first direction X. Each third laser beam 7 corresponds to one detection point, thereby providing positioning for multiple detection points in the second direction Y.

[0102] The electron optical inspection head, together with the main body of the equipment 9, can perform feature dimension measurement to detect the size of the photoresist pattern on the wafer 4; it can perform defect detection to detect tiny defects on the surface of the wafer 4; and it can also be equipped with an energy scattering spectrometer to perform compositional analysis to analyze the elemental composition on the surface of the wafer 4.

[0103] The geometric optical inspection head, together with the main body 9 of the equipment, can perform appearance and structural inspection, observe the appearance morphology of wafer 4, and detect defects such as scratches, cracks, and contamination on the surface of wafer 4; it can perform failure site analysis, observe the surface morphology of the failure site, and determine the cause of failure; it can perform metallographic analysis, and analyze parameters such as grain size, shape, and distribution of wafer 4.

[0104] The deep ultraviolet geometric optical inspection head, together with the main body of the equipment 9, can use deep ultraviolet light as a light source to focus, transmit and control the light, and inspect the size, surface finish, flatness, thickness and shape of the wafer 4.

[0105] In the technical solution of the above embodiment, the main body 9 of the device is equipped with an electro-optical detection head, a geometrical optical detection head, and a deep ultraviolet geometrical optical detection head, which can perform various forms of detection on the wafer 4. The detection points formed by the electro-optical detection head, the geometrical optical detection head, and the deep ultraviolet geometrical optical detection head when detecting the wafer 4 are positioned one-to-one by the first laser beam 5 and multiple third laser beams 7, which can improve the positioning accuracy during detection.

[0106] In some embodiments, as shown in Figures 1, 2, and 4, the wafer inspection system includes a main body 9 and a laser positioning device. The main body 9 is equipped with a first inspection head 91, a second inspection head 92, and a third inspection head 93. The first inspection head 91 is an electro-optical inspection head, the second inspection head 92 is a geometrical optics inspection head, and the third inspection head 93 is a deep ultraviolet geometrical optics inspection head. The inspection modes of the wafer inspection system include SEM (electro-optical) mode, OM (geometrical optics) mode, and DUV (deep ultraviolet geometrical optics) mode. The center distance deviation between the first inspection head 91 and the second inspection head 92 is a first center distance L1, and the center distance deviation between the first inspection head 91 and the third inspection head 93 is a second center distance L2. The laser positioning device is mounted on the main body 9 and includes a stage 1, an orthogonal test feedback element 2, and an optical path element 3. The stage 1 includes a moving mechanism 11, a carrier 12, and a measuring mirror 13. The moving mechanism 11 includes a first moving mechanism 112 (equipped with a first grating ruler 1121) that translates in the first direction X, and a second moving mechanism 111 (equipped with a second grating ruler 1111) that translates in the second direction Y. The second moving mechanism 111 is mounted on the first moving mechanism 112, and the second direction Y is perpendicular to the first direction X. The mounting plate of the carrier 12 is mounted on the second moving mechanism 111, the suction cup is mounted on the mounting plate, and the measuring mirror 13 is mounted on the mounting plate. The top surface of the measuring mirror 13 is lower than the bearing surface of the suction cup. The first measuring surface 131 and the second measuring surface 132 of the measuring mirror 13 are perpendicular to each other. The first measuring surface 131 is perpendicular to the first direction X, and the second measuring surface 132 is perpendicular to the second direction Y. In the second direction Y, the length of the first measuring surface 131 is 300 mm; in the first direction X, the length of the second measuring surface 132 is 300 mm, which can provide a positioning reference for a wafer 4 with a diameter of 300 mm. The optical path element 3 includes a first beam splitter 311, a second beam splitter 312, and a reflector 321.

[0107] The first laser beam 5 emitted by the first measuring head 21 is directed perpendicularly to the first measuring surface 131 along the first direction X, providing the positioning of the detection points of the first detection head 91, the second detection head 92, and the third detection head 93 on the wafer 4 in the first direction X. The second laser beam 6 emitted by the second measuring head 22 is directed towards the first beam splitter 311, and is transmitted through the first beam splitter 311 to form a first third laser beam 7. This third laser beam 7 is directed perpendicularly to the second measuring surface 132 along the second direction Y, providing the positioning of the detection point of the first detection head 91 on the wafer 4 in the second direction Y. The second third laser beam 7 is reflected by the second beam splitter 312 to form a second third laser beam 7. This third laser beam 7 is directed perpendicularly to the second measuring surface 132 along the second direction Y, providing the positioning of the detection point of the second detection head 92 on the wafer 4 in the second direction Y. The third laser beam 7 is formed by reflection on the reflector 321. The third laser beam 7 is directed perpendicularly to the second measurement surface 132 along the second direction Y, which can provide the positioning of the detection point of the third detection head 93 on the wafer 4 in the second direction Y.

[0108] When positioning the first detection head 91, the second detection head 92, and the third detection head 93, the first laser beam 5 is located on the straight line of positioning in the first direction X, the first laser beam is located on the straight line of positioning in the second direction Y, the second laser beam is located on the straight line of positioning in the second direction Y, and the third laser beam is located on the straight line of positioning in the second direction Y. This reduces Abbe error and improves positioning accuracy. Positioning is achieved by using a set of orthogonal test feedback elements 2 and a set of optical path elements 3 in conjunction, which is simple to operate, has low material costs, high positioning accuracy, and stable and reliable positioning accuracy.

[0109] The above description is merely a specific embodiment of this disclosure. Those skilled in the art will readily understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the scope of protection of this disclosure is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this disclosure, and these modifications or substitutions should all be covered within the scope of protection of this disclosure.

[0110] 1: Stage 11: Mobile mechanism 111: Second moving mechanism 1111: Second grating ruler 112: First moving mechanism 1121: First grating ruler 12: Bearing components 13: Measuring mirror 131: First measuring surface 132: Second measuring surface 2: Orthogonality Test Feedback Component 21: First measuring head 22: Second measuring head 23: Orthogonality Test Feedback Subject 3: Optical path components 31: Spectrometer 311: First beam splitter 312: Second beam splitter 32: Reflection Component 321: Reflector 4: Wafer 5: First laser beam 6: Second laser beam 7: Third laser beam 8: First reflected laser beam 9: Main body of the equipment 91: First detection head 92: Second detection head 93: Third detection head L1: First center distance L2: Second center distance X: First direction Y: Second direction

Claims

1. A laser positioning device, comprising: A stage includes a moving mechanism, a carrier, and a measuring mirror. The moving mechanism drives the carrier to move in a first direction and a second direction. The measuring mirror is mounted on the carrier, with its first measuring surface intersecting the first direction and its second measuring surface intersecting the second direction. An orthogonality test feedback element includes a first measuring head and a second measuring head. The first measuring head emits a first laser beam along the first direction toward the first measuring surface, and the second measuring head emits a second laser beam. An optical path element is used to split the second laser beam into multiple third laser beams and direct them toward the second measuring surface along the second direction. The first laser beam and the third laser beams are both located on a straight line along the detection point positioning direction. The first laser beam and the multiple third laser beams form multiple intersection points on the optical path, each intersection point corresponding to a detection point, thus achieving the positioning of multiple detection points.

2. The laser positioning device as claimed in claim 1, wherein, The optical path element includes a beam splitter and a reflector; the beam splitter is located in the optical path of the second laser beam and is used to split the second laser beam into a first reflected laser beam and a third laser beam; the reflector is located in the optical path of the first reflected laser beam and is used to reflect the first reflected laser beam into another third laser beam.

3. The laser positioning device as described in claim 2, wherein, The beam splitter includes a first beam splitter, one side of which is the second laser beam and the first reflected laser beam, and the other side of which is the third laser beam; the reflector includes a reflector, one side of which is the first reflected laser beam and the third laser beam.

4. The laser positioning device as described in claim 3, wherein, The beam splitter further includes a second beam splitter located between the first beam splitter and the reflector, for transmitting the first reflected laser beam and forming the third laser beam.

5. The laser positioning device as described in claim 3, wherein, The angle between the first reflected laser beam and the second laser beam is 90°; the angle between the first reflected laser beam and the third laser beam is 90°.

6. The laser positioning device as claimed in claim 4, wherein, The transmission-to-reflection ratio of the first beam splitter is 1:2, and the transmission-to-reflection ratio of the second beam splitter is 1:

1.

7. The laser positioning device as claimed in claim 1, wherein, The carrier includes a mounting plate and a suction cup; the mounting plate is mounted on the moving mechanism, and the suction cup is mounted on the mounting plate; the measuring mirror is mounted on the mounting plate, the height of the measuring mirror is lower than the height of the suction cup, the first measuring surface of the measuring mirror is perpendicular to the first direction, the second measuring surface of the measuring mirror is perpendicular to the second direction, and the first measuring surface is perpendicular to the second measuring surface.

8. The laser positioning device as claimed in claim 1, wherein, The moving mechanism includes a first moving mechanism and a second moving mechanism; the first moving mechanism is provided with a first grating ruler, the first moving mechanism is used to move in a first direction, and the first grating ruler is used to provide operation control for the first moving mechanism; the second moving mechanism is mounted on the first moving mechanism, the second moving mechanism is provided with a second grating ruler, the second moving mechanism is used to move in a second direction, and the second grating ruler is used to provide operation control for the second moving mechanism.

9. A wafer inspection system, comprising: The main body of the equipment and the laser positioning device as described in any one of claims 1 to 8; The main body of the device is equipped with multiple detection heads, which are located above the stage and are used to detect the wafers on the stage. The detection points of the multiple detection heads are respectively located at the intersection of the first laser beam path and the third laser beam path.

10. The wafer inspection system as described in claim 9, wherein, The detection head includes a first detection head, a second detection head, and a third detection head; the first detection head is an electro-optical detection head, the second detection head is a geometrical optical detection head, and the third detection head is a deep ultraviolet geometrical optical detection head.

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