An inspection system, an inspection control method, a defect inspection apparatus, and an inspection method

Abstract

The present application relates to the technical fields of semiconductor front-end detection, relates to differential interference detection technology, and particularly relates to a detection system, a detection control method, a defect detection device and a detection method. The size of a shaped light spot can be adjusted according to detection requirements, so that the interference signal is enhanced, and the accuracy of detection results and the detection efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor front-end detection, and relates to differential interference detection technology, and in particular to a detection system, a detection control method, a defect detection device and a detection method. BACKGROUND

[0002] In the existing semiconductor front-end defect detection method, a coherent signal reflected by a sample surface can be obtained in the light path of the differential interference contrast method, and different defect sizes, defect reflectivity differences and shapes have different influences on the detection results. SUMMARY

[0003] Therefore, the present application aims to provide a detection system, a detection control method, a defect detection device and a detection method, which can adjust the light path of the detection system according to the detection requirements, so as to enhance the interference signal.

[0004] In a first aspect, an embodiment of the present application provides a detection system, comprising: a beam splitting prism, which splits an incident light beam into a first beam and a second beam, the first beam and the second beam have a circular cross section, and form corresponding first and second light spots on a surface of a measured object, the first and second light spots have different polarization directions; and a controller, which is configured to adjust the center distance and the cross-sectional size of the first and second light spots, so that the center distance of the first and second light spots is greater than the defect size, and the center distance of the first and second light spots is less than the light spot diameter, and the defect size is determined based on a detection task.

[0005] In some specific implementations, the controller adjusts the beam splitting angle of the beam splitting prism to change the center distance of the first and second light spots.

[0006] In some specific implementations, the beam splitting prism comprises a beam splitting prism array, and the array comprises a plurality of Nomarski prisms with different beam splitting angles.

[0007] In some specific implementations, an amplifier is arranged in the light propagation path of the incident light beam, and the amplifier is configured to expand the incident light beam to make the incident light beam have a corresponding entrance pupil diameter and then enter the beam splitting prism.

[0008] In some specific implementations, the amplifier adjusts the expansion parameter to change the entrance pupil diameter, and the controller adjusts the cross-sectional size of the first and second light spots based on the change of the entrance pupil diameter.

[0009] In some specific implementations, the amplifier comprises any one of an expander mirror and a variable diaphragm.

[0010] In some embodiments, the entrance pupil diameter is changed by adjusting a divergence angle of the beam expander.

[0011] In some embodiments, the entrance pupil diameter is changed by adjusting an aperture of the variable aperture.

[0012] In some embodiments, the first beam and the second beam are projected on a surface of an object to be measured after passing through an objective lens group, the controller is connected to the objective lens group, and the cross-sectional size of the first spot and the second spot is changed by adjusting a focal length of the objective lens group.

[0013] In some embodiments, a laser is further included for generating the incident light beam, the controller is connected to the laser, and the cross-sectional size of the first spot and the second spot is changed by adjusting a wavelength of the laser.

[0014] In a second aspect, a detection control method is provided, the method comprising: emitting an incident light beam; splitting the incident light beam into a first beam and a second beam, the first beam and the second beam having a circular cross-section; determining a defect size based on a detection task, and adjusting a cross-sectional size and a relative position relationship of the first beam and the second beam, so that a difference between a center distance and a spot diameter of a first spot and a second spot formed on a surface of an object to be measured is less than the defect size.

[0015] In some embodiments, the adjusting the cross-sectional size of the first beam and the second beam comprises one or more of adjusting a splitting angle, adjusting an entrance pupil diameter of the incident light beam, adjusting a focal length of an objective lens group, and adjusting a wavelength of the incident light beam.

[0016] In some embodiments, the adjusting the entrance pupil diameter of the incident light beam comprises adjusting a divergence angle of a beam expander.

[0017] In some embodiments, the adjusting the entrance pupil diameter of the incident light beam comprises an aperture of a variable aperture.

[0018] In a third aspect, a defect detection device is provided, comprising: a processor configured to determine a detection task, determine a target defect size based on the detection task, and send the target defect size to a controller; the controller configured to perform any of the detection control methods described above, and based on any of the detection systems described above, emit a first spot and a second spot having a target size to a surface of an object to be measured, and form an interference light on the surface to be measured; and a detection assembly configured to receive the interference light and obtain an interference light intensity distribution in the interference light.

[0019] In some specific implementation manners, the interference light intensity distribution is combined from the interference light intensity distribution of the first light spot and the interference light intensity distribution of the second light spot.

[0020] In a fourth aspect, a defect detection method is provided, which comprises: determining a target defect size based on a detection task; determining target light spot sizes of a first light spot and a second light spot based on the target defect size; emitting an incident light beam and dividing the incident light beam into a first beam and a second beam, and the first beam and the second beam are beams with different polarization directions; adjusting the cross-sectional sizes of the first beam and the second beam to the target light spot sizes, and forming interference light on a surface to be detected; receiving the interference light and obtaining an interference light intensity distribution in the interference light.

[0021] In some specific implementation manners, the target defect size is determined based on the detection task, comprising: determining a target defect size range based on the detection task; and taking a middle value of the target defect size range as the target defect size.

[0022] The embodiments of the present application have the following beneficial effects:

[0023] The embodiments of the present application provide a detection system, a detection control method, a defect detection device and a detection method, which can adjust the size of a forming light spot according to detection requirements, so that the interference signal is enhanced, and the accuracy and efficiency of the detection result are improved.

[0024] Other features and advantages of the present disclosure will be described in the following description, or can be learned from the description, or can be determined without doubt, or can be known by implementing the above-mentioned technologies of the present disclosure.

[0025] In order to make the above-mentioned purposes, features and advantages of the present disclosure more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0027] The methods, systems and / or programs in the drawings will be further described according to the exemplary embodiments. These exemplary embodiments will be described in detail with reference to the drawings. These exemplary embodiments are non-limiting exemplary embodiments, in which the example numbers represent similar mechanisms in each view of the drawings.

[0028] Figure 1A light intensity distribution diagram provided for the embodiment;

[0029] Figure 2 Another light intensity distribution diagram provided for the embodiment;

[0030] Figure 3 A detection system structure diagram provided for the embodiment;

[0031] Figure 4 A detection method flow diagram provided for the embodiment;

[0032] Figure 5 A defect detection device structure diagram provided for the embodiment;

[0033] Figure 6 A principle light path diagram provided for the embodiment;

[0034] Figure 7 A defect detection method flow diagram provided for the embodiment. DETAILED DESCRIPTION

[0035] In order to better understand the above technical solutions, the technical solutions of the present application will be described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, and are not limitations of the technical solutions of the present application. In the case of no conflict, the technical features in the embodiments of the present application and the embodiments can be combined with each other.

[0036] In the following detailed description, many specific details are set forth in order to provide a thorough understanding of relevant guidance. However, it is obvious to those skilled in the art that the present application can be implemented without these details. In other cases, well-known methods, procedures, systems, components and / or circuits have been described at a relatively high level without details, in order to avoid unnecessary obscuring aspects of the present application.

[0037] The flowchart in the present application illustrates the execution processes performed by the system according to the embodiments of the present application. It should be explicitly understood that the execution processes of the flowchart can not be executed in sequence. On the contrary, these execution processes can be executed in reverse order or simultaneously. In addition, at least one other execution process can be added to the flowchart. One or more execution processes can be deleted from the flowchart.

[0038] Embodiments of the present application provide a DIC (Differential Interference Contrast) imaging detection system, which is applied to a semiconductor front-end detection scenario and is particularly used for defect detection on a wafer surface. In this regard, the working principle of the DIC detection system is to use a prism to separate polarized incident white light into two beams of light, which are generally o light and e light. The two beams of light are reflected from the surface of a sample and then pass through the prism again before being combined. The recombined beams of light interfere with each other to form elliptically polarized light. Through this interference, the small height changes of the surface and structure of the wafer can be observed.

[0039] In this regard, the "wafer" in the embodiments generally refers to a substrate formed of a semiconductor or non-semiconductor material. Examples include, but are not limited to, monocrystalline silicon, gallium arsenide, gallium nitride, and indium phosphide. Such substrates can generally be found and / or processed in a semiconductor manufacturing facility. In some cases, the wafer can include only a substrate (i.e., a bare wafer). Alternatively, the wafer can include one or more layers of different materials formed on the substrate. One or more layers formed on the wafer can be "patterned" or "unpatterned". For example, the wafer can include a plurality of dies having repeatable pattern features.

[0040] Referring to Figure 1 , a detection light beam and a corresponding light intensity distribution state result. Referring to Figure 1 a, the two sub-beams after polarization splitting are in an independent state, that is, the polarized light after splitting forms two sub-beams in a non-overlapping relationship. The black dot indicates that the defect will cause reflectivity and phase delay. In this figure, the defect is located on one sub-beam alone, and the other sub-beam does not irradiate the defect.

[0041] The light intensity distribution signal obtained based on this case is shown in Figure 1 b, Figure 1 b is the light intensity distribution generated after the interference of the two sub-beams. The left side of b respectively shows the light intensity distributions of the two sub-beams. Since one of the sub-beams does not irradiate the defect, it does not have a light intensity loss. Therefore, the interference light intensity obtained is the interference signal shown on the right side of b.

[0042] Referring to Figure 2 , another detection light beam and a corresponding light intensity distribution state result. Referring to Figure 2 a, the two sub-beams after polarization splitting and Figure 1 are different in that they are in an overlapping relationship, and the corresponding defects are in an overlapping position. That is, both of the two sub-beams irradiate the defect position. The light intensity distribution corresponding to the detection light beam is shown in Figure 2 b, the result of Figure 2 b shows that for the same defect, the light intensity signal obtained by using the detection light beam in this way is Figure 1 twice the detection light beam.

[0043] Therefore, for the detection system provided in the embodiment of the present application, based on the differential interference detection method, the relative position of the shaped light spots is controlled to maximize the light intensity of the finally obtained interference signal, thereby improving the detection effect and detection efficiency.

[0044] Wherein, the control logic thereof is to control the overlap of the shaped light spots of the two sub-beams, and the overlap area should be larger than the spot size.

[0045] Therefore, referring to Figure 3 For the detection system 30 of the embodiment, at least includes a beam splitter prism 32 and a controller 33 connected with the beam splitter prism, and a laser 31 is also needed to be arranged to generate an incident light beam.

[0046] Wherein, the beam splitter prism is a basic optical component of the differential interference observation method, which is used to split the incident light beam to form a first beam and a second beam, and this setting has a circular cross section to form corresponding first and second light spots on the surface of the object to be measured, i.e. the wafer surface, wherein the first and second light spots have different polarization directions.

[0047] Specifically, in the embodiment, the first light spot is o light and the second light spot is e light.

[0048] The setting of the beam splitter prism is a basic optical component in the differential interference method, which will not be described again. For the controller, it is the main component in the embodiment, which is used to adjust the cross-sectional size of the first and second light spots to form an overlap area by overlapping the first and second light spots, and the overlap area should be larger than the defect size.

[0049] Specifically, for the controller to adjust the center distance of the first and second light spots, the difference between the center distance and the spot diameter should be larger than the defect size, and the center distance should be smaller than the spot diameter. That is, the overlap of the two light spots is realized by adjusting the center distance of the first and second light spots, and the area after overlap should be larger than the defect of the wafer to be detected.

[0050] Wherein, the defect size is determined based on the detection task, i.e. first determine the defect type and the size of the defect type through the detection task, and then control through the controller.

[0051] In the embodiment, the center distance of the o light and the e light is determined based on the following formula: y = f tan θ, wherein f is the focal length of the mirror group and θ is the separation angle of the beam splitter prism. It can be known from the formula that under the condition that the focal length is unchanged, the center distance of the first and second light spots can be adjusted by controlling the separation angle of the beam splitter prism.

[0052] Therefore, in the embodiment, the center distance of the first light spot and the second light spot is adjusted by adjusting the splitting angle of the beam splitter prism.

[0053] Specifically, the beam splitter prism in the embodiment includes a beam splitter prism array, and each beam splitter prism in the array has a different splitting angle, i.e., a separation angle. The defect size is determined by the detection task, the center distance of the first light spot and the second light spot is determined based on the defect size, the separation angle range of the beam splitter prism is determined, and a beam splitter prism in the separation angle range is selected to receive the incident light beam and form the first light spot and the second light spot with the target center distance.

[0054] In the embodiment, the movement of each beam splitter prism in the beam splitter prism array is based on a configured motor, i.e., the motor drives the beam splitter prism into or out of the optical path in the detection system.

[0055] Through the above structure, the first light spot and the second light spot with the target center distance can be obtained, but it is worth noting that the size of the light spot is defaulted to be larger than the defect size in the above structure. However, in actual situations, the size of the light spot also needs to be adjusted according to different defect types and corresponding defect sizes, so that the size of the first light spot and the second light spot should be larger than the defect size.

[0056] However, it is worth noting that if only the separation angle of the beam splitter prism is adjusted, the adjustment of the light spot size cannot be realized.

[0057] Therefore, in order to solve the technical problem, an optical device capable of adjusting the size of the shaped light spot is also provided in the detection system.

[0058] In an embodiment, the optical device is an expander 34. By providing the expander, the incident light beam is expanded, so that the incident light beam produces a corresponding entrance pupil diameter after entering the beam splitter prism array for center distance adjustment.

[0059] The control of the expander changes the entrance pupil diameter by adjusting the expansion parameter of the expander, and changes the cross-sectional size of the first light spot and the second light spot based on the change of the entrance pupil diameter.

[0060] Specifically, the expander in the embodiment includes any one or more of an expander mirror and a variable diaphragm. For adjusting the light spot size by using the expander mirror, the entrance pupil diameter is changed by controlling the divergence angle of the expander mirror; for adjusting the light spot size by using the variable diaphragm, the entrance pupil diameter is changed by controlling the diaphragm aperture of the variable diaphragm.

[0061] Setting the amplifier to adjust the spot size is one embodiment, and is not the only way to achieve this embodiment. The embodiment also provides some other embodiments to achieve the adjustment of the spot size.

[0062] Specifically, according to the calculation formula of the spot diameter size: It can be seen that λ is the wavelength of the incident light beam, f is the focal length of the lens group, and p is the entrance pupil diameter. For the change of the spot size, in addition to changing the size of the entrance pupil diameter, the incident light beam wavelength and the focal length of the lens group can also be adjusted.

[0063] Therefore, in another embodiment, the adjustment of the incident light beam wavelength is achieved by setting a multi-wavelength light source. Therefore, for the laser 31, a multi-wavelength laser is preferred in this embodiment, and the adjustment of the incident light beam wavelength is achieved by adjusting the set wavelength of the laser.

[0064] In addition to the above embodiments, the adjustment of the spot size can also be achieved by setting a zoom lens group 32 with adjustable focal length.

[0065] Specifically, the zoom lens group is set before the test object, i.e. after the beam splitter prism, to adjust the focal length and thus adjust the size of the formed spot.

[0066] Among them, the zoom lens group in this embodiment is an objective lens group that can change the focal length of the light beam, and the change of the focal length of the incident light beam is achieved by adjusting the relative distance of the optical lenses of the objective lens group, so as to adjust the cross-sectional size of the first spot and the second spot. It is worth noting that the combination of optical lenses of this objective lens group can meet the requirement of adjustable focal length, and the combination of optical lenses in this embodiment is not limited, and the implementation means can be any objective lens group with adjustable focal length in the prior art; it can also be any optical device with adjustable focal length in the prior art. As long as the focal length can be changed, it falls within the protection scope of this embodiment.

[0067] According to the above structure, it can be known that at least one beam splitter prism array capable of adjusting the center distance between the first spot and the second spot should be included in this embodiment, and a plurality of beam splitter prisms are arranged in the array, each beam splitter prism corresponds to a different separation angle range, and the center distance between the first spot and the second spot is adjusted by selecting the beam splitter prism corresponding to the separation angle, so that the first spot and the second spot have an overlapping area; one or more devices capable of adjusting the spot size should also be included, which are amplifiers, multi-wavelength lasers and zoom lens groups, respectively, to adjust the size of the first spot and the second spot, so that the difference between the center distance of the finally formed first spot and second spot and the spot diameter is greater than the defect size, and the center distance between the first spot and the second spot is less than the spot diameter.

[0068] Referring toFigure 4 According to the detection system, a detection control method is also provided, comprising the following steps:

[0069] Step 41. Emit an incident light beam.

[0070] Step S42. Divide the incident light beam into a first beam and a second beam.

[0071] In this embodiment, the first beam and the second beam can also be referred to as a first light beam and a second light beam, wherein the first beam and the second beam both have a circular cross section.

[0072] Step S43. Determine a defect size based on a detection task, and adjust the cross-sectional size and relative position relationship of the first beam and the second beam, so that the difference between the center-to-center distance and the spot diameter of the first spot and the second spot formed on the surface of the object to be detected is greater than the defect size, and the center-to-center distance of the first spot and the second spot is less than the spot diameter.

[0073] Wherein, the first spot and the second spot are respectively formed by the first beam / first light beam and the second beam / second light beam on the surface of the object to be detected. In this embodiment, the object to be detected is a wafer, and the surface of the object to be detected is the surface of the wafer.

[0074] In this embodiment, by controlling the formed size and distance difference of the first spot and the second spot on the surface of the wafer, the optical information of the corresponding type of defects on the surface of the wafer is collected.

[0075] Wherein, the adjustment of the cross-sectional size of the first beam and the second beam is realized by adjusting one or more of the following: the beam splitting angle, the entrance pupil diameter of the incident light beam, the focal length of the objective lens group, and the wavelength of the incident light beam.

[0076] Specifically, the center-to-center distance of the first spot and the second spot is adjusted by adjusting the beam splitting angle, and the size of the first spot and the second spot is adjusted by adjusting the entrance pupil diameter, the focal length of the objective lens group, and the wavelength of the incident light beam, so that the difference between the center-to-center distance and the spot diameter of the first spot and the second spot is greater than the defect size, and the center-to-center distance of the first spot and the second spot is less than the spot diameter.

[0077] In one embodiment, the adjustment of the entrance pupil diameter of the incident light beam is realized by adjusting the divergence angle of the beam expander.

[0078] In another embodiment, the adjustment of the entrance pupil diameter can also be realized by adjusting the aperture of the variable diaphragm.

[0079] The above two implementation manners can be implemented as the embodiments of the present embodiment, and the combination of the above two implementation manners can also be implemented as the embodiments of the present embodiment.

[0080] Referring to Figure 5 For the above detection system, the present embodiment further provides a defect detection device 50, which is configured based on the detection system, and is further configured with a processor 51 and a detector assembly 54.

[0081] The processor is configured to determine a detection task, determine a target defect size based on the detection task, configure a corresponding target spot feature based on the target defect size, and issue the target spot feature information to a controller in the detection system.

[0082] The controller receives the above spot feature information, and performs detection control based on steps S41-S42, emits a shaped spot with the target spot feature to the wafer surface through the detection system, and forms a signal light to the detector assembly through the wafer surface reflection.

[0083] The detector assembly is configured to receive the generated interference light signal and obtain the interference light intensity distribution in the interference light signal.

[0084] The interference light signal received by the detector assembly is realized by a beam splitter prism 52 arranged in the reflection path, that is, the beam splitter prism makes the incident light beam pass through and enter the beam splitter prism in the incident light path, and the reflected light passing through the beam splitter prism in the reflection light path is subjected to beam splitting processing to form reflected light in orthogonal relationship with the original reflection light path and received by the detector.

[0085] Specifically, the beam splitter prism in the present embodiment is a non-polarized beam splitter prism, which realizes the beam splitting processing of the reflection light path. This scheme can also use any optical device for receiving light signals in the prior art, as long as it can process the reflection light path into the detector assembly without affecting the propagation of the incident light beam.

[0086] In addition, a polarizer 53 is arranged in the beam-splitting reflection light path for forming interference light. Specifically, the polarizer has a polarization direction of 45°, and the polarizer is used to generate interference light of o light and e light in this direction, so that the signal light received by the detector assembly is interference signal, and the light intensity is interference signal light intensity.

[0087] In the present embodiment, the target spot feature is the first spot target size and the second spot target size, and the center distance between the first spot and the second spot.

[0088] The interference light intensity distribution is composed of the interference light intensity distribution of the first spot and the interference light intensity distribution of the second spot.

[0089] In the embodiment, the defect detection device performs detection based on differential interference method, and a corresponding defect detection result is determined based on the obtained interference signal light intensity distribution. The interference signal light intensity distribution is determined based on the field intensity distribution and the phase delay distribution.

[0090] Specifically, for the interference signal light intensity distribution determination process, please refer to Figure 6 , Figure 6 The defect detection device detection logic diagram.

[0091] The xy plane is the focusing plane of the beam splitter prism or the entrance pupil plane of the objective lens, Up is the complex field distribution of the plane, and P is the aperture distribution of the plane. The uv plane is the sample surface to be detected, Uo is the complex field distribution of o light of the plane, Ue is the complex field distribution of e light of the plane, R is the reflection distribution of the plane, and D is the reflection phase delay distribution caused by the defect of the plane. The x'y' plane is the focusing plane of the Nomarski prism or the entrance pupil plane of the objective lens after reflection of the light path.

[0092] The ξη plane is the detector surface, Uo' is the complex field distribution of o light of the plane, Ue' is the complex field distribution of e light of the plane, f is the objective lens in front of the sample, and f_detector is the condenser in front of the signal collection of the detector.

[0093] It is worth noting that the above view is an equivalent description diagram, which is used to facilitate the expression of the light path relationship. In the actual scene, the light path is a reflection light path rather than a transmission light path.

[0094] The starting condition is that the field intensity distribution of the incident light of the xy plane is Up, which can be a Gaussian distribution or a flat-top beam. The complex field calculation process of each plane o light and e light is as follows:

[0095] Specifically, the light beam propagates from the xy plane to the uv plane. In the case of no defect, the field intensity distribution has the following characteristics:

[0096]

[0097] ; wherein +m and +n are the spot center distance deviations caused by the difference in the incident angles of o light and e light introduced by the beam splitter prism.

[0098] The uv plane has a defect, which introduces a phase delay, which is represented based on the following formula: Φ(u,v) = knΔ(u,v) + k[Δ h -Δ(u,v)], which is equivalent to a multiplied phase transformation represented as:

[0099] The uv plane with a defect also causes a change in reflectivity. In the current case, the field distribution of the reflected o light and e light becomes:

[0100]

[0101] The propagation of the uv plane light beam to the ξ plane is a first imaging relationship, satisfying the Fourier integral theorem.

[0102] The reflected light path passes through the beam-splitting prism again, resulting in a fixed phase difference. The beam-splitting prism can further process the e light in the ξ plane by -m, -n to obtain the following e light complex field distribution:

[0103]

[0104] The o light and e light field intensity distributions received by the detector can be calculated through the above processing. By setting a polarizer with a 45° direction, interference light of the o light and e light in the direction can be generated. The interference light intensity can be calculated using the currently calculated field intensity distribution and phase delay distribution. The calculation process can be implemented based on the existing technical solutions, and will not be described in detail in the embodiments of the present application.

[0105] Referring to Figure 7 Based on the above defect detection device, the embodiment further comprises a detection method, comprising the following steps:

[0106] Step S71. Determine the target defect size based on the detection task.

[0107] Step S72. Determine the target spot size of the first spot and the second spot based on the target defect size.

[0108] Step S73. Emit an incident light beam, and divide the incident light beam into a first beam and a second beam, wherein the first beam and the second beam are beams with different polarization directions.

[0109] Step S74. Adjust the cross-sectional size of the first beam and the second beam to the target spot size, and form interference light on the surface to be measured.

[0110] Step S75. Receive the interference light and obtain the interference light intensity distribution in the interference light.

[0111] In the embodiment, the detection task is to detect the defect type and the corresponding defect size range. The detection task is configured based on the front end, which can be understood as a detection instruction issued to the processor, and the detection instruction includes the target defect size. The detection task is constructed based on all defect types and corresponding defect sizes obtained in the actual scene. The actual scene is not limited to all defect data recorded by the defect detection equipment, but also includes defect data recorded by other defect detection equipment and possible defect data obtained by inference. Therefore, the detection task includes all actual and possible defect types and corresponding defect size data in the actual scene.

[0112] As to how to determine the detection task, both automatic mode and manual mode are included. In the automatic mode, the corresponding detection task is automatically generated by selecting the defect type, which has been configured with the corresponding defect size range. In the manual mode, the detection task is determined by manually selecting the defect size range to be detected. However, the strategy of setting the upper limit and lower limit of the detection task is also included in the manual mode. The strategy reduces the problem of inaccurate detection results caused by the too large or too small defect size range selected manually.

[0113] In the embodiment, the target defect size is determined based on the defect size range in the received detection task instruction. Because the defect configured in the detection task is range data, the range data needs to be converted to numerical data when determining the target defect size. The specific processing method is to take the middle value of the target defect size range as the target defect size, and determine the target spot size of the first spot and the second spot based on the target defect size. Finally, the wafer to be detected is scanned based on the target spot size, the interference light is obtained, and the defect is detected according to the interference light intensity distribution of the interference light.

[0114] The embodiment of the application provides a detection system, a detection control method, a defect detection equipment and a detection method. The size of the shaped spot can be adjusted according to the detection requirement, so that the interference signal is enhanced, and the accuracy and efficiency of the detection result are improved.

[0115] Notably, the processor in the present embodiments includes any processing element known in the art. In this sense, the processor can include any microprocessor-type device configured to execute algorithms and / or instructions. In one embodiment, the one or more processors can be comprised of a desktop computer, a mainframe computer system, a workstation, a graphics computer, a parallel processor, or any other computer system (e.g., networked computers) configured to execute a program configured to operate a system / device as described throughout the present disclosure. It should be further recognized that the term "processor" can be broadly defined to encompass any device having one or more processing elements that execute program instructions from a non-transitory memory medium. Accordingly, the above description should not be interpreted as a limitation on the present application but merely an illustration.

[0116] The memory medium can include any storage medium suitable for storing program instructions executable by the associated one or more processors. By way of non-limiting example, the memory medium can include a non-transitory memory medium. By way of further non-limiting example, the memory medium can include, but is not limited to, read-only memory, random access memory, magnetic or optical storage devices (e.g., diskettes, magnetic tapes, solid state drives, etc.). It should further be noted that the memory can be housed in a common controller housing with the one or more processors. In alternative embodiments, the memory can be remotely located relative to the physical location of the one or more processors and controller. For example, the one or more processors of the controller can access a remote memory (e.g., a server) that can be accessed over a network (e.g., the Internet, an intranet, etc.).

[0117] Those skilled in the art will recognize that the components, operations, devices, objects, and the discussion accompanying them are used as examples for the sake of conceptual clarity and that various configuration modifications are contemplated. Consequently, as used herein, the specification is intended to be understood to be a description of the underlying inventive concepts and their broader classes and not a specific, limiting description for the sole purpose of enabling the application. Accordingly, the description intended to be illustrative and not restrictive, and the scope of the application is to be determined not with reference to the accompanying text describing the exemplary embodiments, but rather with reference to the claims.

[0118] With respect to the use of substantially any plural and / or singular terms herein, those having skill in the art can translate the plural and / or singular terms to a singular and / or plural form, as appropriate, in view of the context in which the plural and / or singular terms are used. For the sake of clarity, various singular / plural permutations are not expressly set forth.

[0119] The subject matter described herein is sometimes illustrated using different components contained within, or connected with, other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other to achieve the particular functionality, irrespective of architectures or intermediate components. Likewise, any two components that are so associated can also be viewed as being "connected" or "coupled" to each other to achieve the particular functionality, and any two components that are so connectable can also be viewed as being "couplable" to each other to achieve the particular functionality. Specific examples of couplable include but are not limited to physically mateable and / or physically interacting components and / or wirelessly interactable and / or wirelessly interacting components and / or logically interacting and / or logically interactable components.

[0120] Moreover, it is to be understood that the invention is defined by the appended claims. Those skilled in the art will appreciate that, in general, the use of the terms "including", "containing" or "comprising" and the like in the detailed description, specification, and claims, is used expansively and does not exclude other components, additives, ingredients, or steps. As used herein, the indefinite articles "a" and "an" are intended to have the same meaning and to be equivalent to the definite article "the" unless otherwise noted. As used herein, the term "plurality" is intended to mean two or more. As used herein, the term "comprising" is intended to mean including, but not limited to, and the like. As used herein, the term "including" is intended to mean "comprising" or "consisting of," and the like. As used herein, the term "consisting of" is intended to mean "including," "comprising," or "consisting," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like. As used herein, the term "consisting essentially of" is intended to mean "including," "comprising," or "consisting of," and the like.It will be further understood by those skilled in the art that virtually any disjunctive language, such as any of the terms "or," "and," "at least," "etc.," occurring in the description, claims, or drawings is intended to mean either the listed term or any of the singular items in the list exclusive, or in the alternatives (alternatives) of the listed term. For example, "A or B" is intended to mean either "A" or "B" or "A and B."

[0121] It is believed that many advantages of the present disclosure, and its attendant benefits, will be appreciated and understood by those of ordinary skill in the art upon reading the foregoing description and upon inspecting the accompanying drawings. It will be understood by those within the art that while the application has been fully described by example with reference to various drawing figures, the description is illustrative and the application is not limited to the specific embodiments disclosed. One skilled in the art will readily devise their own methods, structures, and materials based on the preceding description and illustrations. The application is to be limited only by the claims.

Claims

1. A detection system, characterized in that, include: A beam splitter prism splits the incident beam into a first beam and a second beam. The first beam and the second beam have circular cross-sections and form corresponding first and second light spots on the surface of the object to be measured. The first light spot and the second light spot have different polarization directions. The controller is used to adjust the center-to-center distance and cross-sectional size of the first and second light spots, such that the difference between the center-to-center distance and the spot diameter is greater than the defect size, and the center-to-center distance between the first and second light spots is less than the spot diameter; the defect size is determined based on the detection task.

2. The detection system according to claim 1, characterized in that, The controller adjusts the beam splitting angle of the beam splitting prism to change the center distance between the first light spot and the second light spot.

3. The detection system according to claim 2, characterized in that, The beam splitter includes a beam splitter array, which includes multiple Normask prisms or Wollaston prisms with different beam splitting angles.

4. The detection system according to claim 1, characterized in that, An amplifier is provided in the light propagation path of the incident beam. The amplifier is used to expand the incident beam so that the incident beam produces a corresponding entrance pupil diameter before entering the beam splitter prism.

5. The detection system according to claim 4, characterized in that, The entrance pupil diameter is changed by adjusting the amplification parameters of the amplifier, and the cross-sectional dimensions of the first and second light spots are changed based on the change in the entrance pupil diameter.

6. The detection system according to claim 5, characterized in that, The amplifier includes either a beam expander or a variable aperture.

7. The detection system according to claim 6, characterized in that, The entrance pupil diameter is changed by adjusting the divergence angle of the beam expander.

8. The detection system according to claim 6, characterized in that, The entrance pupil diameter is changed by adjusting the aperture diameter of the variable aperture.

9. The detection system according to claim 1, characterized in that, The first beam and the second beam are projected onto the surface of the object to be measured after passing through the objective lens group. The controller is connected to the objective lens group and the cross-sectional size of the first spot and the second spot is changed by adjusting the focal length of the objective lens group.

10. The detection system according to claim 1, characterized in that, It also includes a laser for generating an incident beam, and the controller is connected to the laser to change the cross-sectional dimensions of the first and second light spots by adjusting the wavelength of the laser.

11. A detection and control method, characterized in that, The method includes: Emitting an incident beam; The incident beam is divided into a first beam and a second beam, the first beam and the second beam having circular cross-sections; The defect size is determined based on the detection task, and the cross-sectional dimensions and relative positional relationship of the first beam and the second beam are adjusted so that the difference between the center distance of the first spot and the second spot formed on the surface of the object to be tested and the spot diameter is greater than the defect size, and the center distance of the first spot and the second spot is less than the spot diameter.

12. The detection and control method according to claim 11, characterized in that, Adjusting the cross-sectional dimensions of the first beam and the second beam includes: adjusting the beam splitting angle, adjusting the entrance pupil diameter of the incident beam, adjusting the focal length of the objective lens group, and adjusting one or a combination of the wavelengths of the incident beam.

13. The detection and control method according to claim 12, characterized in that, The adjustment of the entrance pupil diameter of the incident beam includes: adjusting the divergence angle of the beam expander.

14. The detection and control method according to claim 12, characterized in that, The adjustment of the entrance pupil diameter of the incident beam includes: adjusting the aperture diameter of the variable aperture.

15. A defect detection device, characterized in that, include: The processor is used to determine the detection task, determine the target defect size based on the detection task, determine the target spot features based on the target defect size, and send the target spot feature information to the controller; A controller is configured to execute the detection control method according to any one of claims 11-14, and based on the detection system according to any one of claims 1-10, to emit a first light spot and a second light spot having target light spot characteristics onto the surface of the object to be tested, and to form interference light through the surface of the object to be tested; A detection component is used to receive the interference light and obtain the intensity distribution of the interference light in the interference light.

16. The defect detection equipment according to claim 15, characterized in that, The interference intensity distribution is composed of the interference intensity distribution of the first spot and the interference intensity distribution of the second spot.

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