Repair using 2D and 3D combinations

Abstract

A repair system may use a laser to repair defects, such as excess material defects and open circuit defects. The repair system may use a method of repairing the defect that combines a 2D image and a 3D measurement during the repair. Combining the 2D image and the 3D measurement during the repair can reduce defect repair time while repairing the finest portion of the defect.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 611,771, filed December 19, 2023, entitled “Repair using combined 2D and 3D,” which is incorporated herein by reference in its entirety, pursuant to 35 USC § 119(e). Technical Field

[0003] This disclosure generally relates to printed circuits, and more specifically, to the repair of printed circuits. Background Technology

[0004] Printed circuits may contain defects from the manufacturing process, such as excess material defects (e.g., short-circuit defects) or missing material defects (e.g., open-circuit defects). Defective printed circuits are either discarded or repaired. Repairing defects is expected to improve yield and reduce waste. Therefore, it would be advantageous to provide an apparatus, system, and method for addressing the disadvantages described above. Summary of the Invention

[0005] A repair system is described according to one or more embodiments of the present disclosure. The repair system may include: a light source configured to generate illumination; a laser generator configured to generate laser light; a biaxial scanner configured to redirect the laser light; a sample stage configured to support a sample; an objective lens configured to pass through the objective lens to the sample to perform repair on a defect located at a defect site on the sample; a detector configured to generate a 2D image of the defect site based on collected light, wherein the collected light is reflected or emitted from the defect site, passes through the objective lens to the detector; and a controller comprising one or more processors configured to execute program instructions stored in a memory, the program instructions causing the controller to: generate a 3D measurement of the defect site; determine a 3D shape of the defect by comparing the 3D measurement with an expected design of the defect site; ablate the 3D shape of the defect by repeatedly performing the following operations: ablate the defect shape by causing the laser light to scan the defect shape in the current layer; locate residues of the defect in the 2D image; and ablate the residues of the defect.

[0006] In some aspects, focus rangefinding is used to generate the 3D measurements.

[0007] In some aspects, the detector is configured to generate multiple 2D images with multiple image-to-image offsets in a focal plane; wherein the 3D measurements are generated from the multiple 2D images.

[0008] In some aspects, the inter-image offset in the focal plane can be reduced toward the substrate of the sample.

[0009] In some aspects, the repair system may include a 3D camera; wherein the controller is configured to cause the 3D camera to generate the 3D measurement.

[0010] In some respects, the program instructions cause the controller to segment the 3D shape into multiple defect shapes stacked together.

[0011] In some aspects, the program instructions cause the controller to determine that the 3D shape has been ablated using open-loop conditions.

[0012] In some aspects, the open-loop condition is the ablation depth at the current layer estimated by the controller using the energy density of the laser light.

[0013] In some aspects, the repair system ablates the 3D shape without generating additional 3D measurements.

[0014] In some respects, the residue of the defect is below the 3D accuracy limit of the 3D measurement.

[0015] In some aspects, the program instructions cause the controller to repeatedly generate the 2D image of the defect location, locate the residue of the defect, and ablate the residue of the defect.

[0016] In some aspects, the program instructions cause the controller to repeatedly generate the 2D image of the defect location, locate the residue of the defect, and ablate the residue of the defect until the controller determines that the residue of the defect is below the allowable defect size.

[0017] In some aspects, the program instructions cause the controller to refocus the laser beam at different depths while repeatedly generating the 2D image of the defect location, locating the residue of the defect, and ablating the residue of the defect.

[0018] In some aspects, the defect is an excess material defect; wherein the laser light repairs the excess material defect by ablating it.

[0019] In some aspects, the memory stores design files and defect reports, wherein the design files contain the intended design.

[0020] In some aspects, the collected light reflected from the sample comprises light emitted by the sample after being excited by at least one of the illumination or the laser light.

[0021] In some aspects, the illumination is directed to the sample in a light field configuration; wherein the illumination and the laser light are configured to pass through the objective lens to the sample.

[0022] In some aspects, the illumination is directed to the sample according to the dark field configuration.

[0023] In some aspects, the controller is configured to ablate the 3D shape of the defect by repeatedly performing the following operations: ablating the defect shape by causing the laser light to scan the defect shape in the current layer; and refocusing the laser light down to the next layer.

[0024] In some aspects, the controller is configured to ablate the defect shape by scanning the defect shape of the defect in the current layer once before refocusing the laser light down to the next layer.

[0025] In some aspects, the controller is configured to ablate the defect shape by scanning the defect shape of the defect in the current layer multiple times before refocusing the laser light down to the next layer.

[0026] In some aspects, the controller is configured to ablate the defect shape by causing the laser light to scan the defect shape of the defect in the current layer multiple times, without refocusing the laser light down to the next layer.

[0027] In some aspects, the controller is configured to: generate additional 3D measurements of the defect location, wherein the additional 3D measurements indicate that the defect is still at the defect location; determine the 3D shape of the defect from the additional 3D measurements; and ablate the 3D shape of the defect.

[0028] According to one or more embodiments of this disclosure, a method is described. The method may include: generating a 3D measurement of a defect location; determining a 3D shape of a defect by comparing the 3D measurement with an expected design of the defect location; ablating the 3D shape of the defect by repeatedly performing the following operations: ablating the defect shape by scanning the defect shape in a current layer with laser light; generating a 2D image; locating residues of the defect in the 2D image; and ablating the residues of the defect. Attached Figure Description

[0029] Those skilled in the art will better understand the many advantages of this disclosure by referring to the accompanying drawings, in which:

[0030] Figure 1 A block diagram depicting a repair system according to one or more embodiments of the present disclosure.

[0031] Figure 2 A flowchart depicting a method for repair using a combination of two-dimensional (2D) images and three-dimensional (3D) measurements according to one or more embodiments of the present disclosure.

[0032] Figure 3A A 2D image depicting the top of a sample having a substrate, excess material defects, and a pair of conductors at the defect locations according to one or more embodiments of the present disclosure.

[0033] Figure 3B A side view depicting a 3D measurement of a sample at the location of a defect according to one or more embodiments of the present disclosure.

[0034] Figure 3C A top view depicting the shape of a defect scanned at the defect location during an ablation cycle according to one or more embodiments of the present disclosure.

[0035] Figure 3D A 2D image depicting the top of a sample at the defect location after scanning the defect shape during an ablation cycle, according to one or more embodiments of the present disclosure, wherein the remaining excess material defect is below the 3D accuracy limit.

[0036] Figure 3E A 2D image depicting the top of a sample at the defect location after scanning based on a previous 2D image, according to one or more embodiments of the present disclosure. Detailed Implementation

[0037] This disclosure has been specifically shown and described with respect to certain embodiments and their particular features. The embodiments set forth herein should be considered illustrative rather than restrictive. It will be readily apparent to those skilled in the art that various changes and modifications in form and detail may be made without departing from the spirit and scope of this disclosure. The disclosed subject matter will now be described in detail with reference to the accompanying drawings.

[0038] The repair system can use lasers to repair defects such as excess material (“short circuit”) and missing material (“open circuit”) defects. The repair system can employ methods for repairing defects that combine 2D imaging and 3D measurement during the repair process. Combining 2D imaging and 3D measurement during repair reduces defect repair time while repairing the finest parts of the defect and eliminating thin residues.

[0039] U.S. Patent No. 8,290,239 entitled "Automatic repair of electric circuits", U.S. Patent No. 2006 / 0226865 entitled "Automatic defect repair system", Chinese Patent No. 114521061 entitled "Method and equipment for repairing short circuit of printed circuit board by using laser", Chinese Patent No. CN217412792U entitled "Laser processing system", and Chinese Patent No. CN113231732A entitled "Laser processing system and control method thereof" are each incorporated herein by reference in their entirety.

[0040] For reference Figure 1 Repair system 100 is described according to one or more embodiments of this disclosure. Repair system 100 may be a repair tool. Repair system 100 includes one or more components, such as, but not limited to, light source 102 (e.g., axial light source), light source 102a (e.g., diffuse light source), beam splitter 104, beam splitter 106, laser generator 108, dual-axis scanner 110 (e.g., fast-turning mirror, a pair of galvanometer scanners, dual-axis acousto-optic deflector, and the like), objective lens 112, sample stage 114, detector 116, controller 118, user interface 120, z-axis positioner 126, z-axis positioner 128, z-axis positioner 130, and the like.

[0041] In an embodiment, the restoration system 100 includes one or more subsystems. Light source 102, light source 102a, beam splitter 104, beam splitter 106, and objective lens 112 may constitute an illumination subsystem. Laser generator 108, dual-axis scanner 110, beam splitter 106, and objective lens 112 may constitute a laser processing subsystem. Objective lens 112, beam splitter 106, beam splitter 104, and detector 116 may constitute an image acquisition subsystem. The illumination subsystem, laser processing subsystem, and image acquisition subsystem may share a common optical path. For example, the illumination subsystem, laser processing subsystem, and image acquisition subsystem may jointly include objective lens 112. As another example, the laser processing subsystem and image acquisition subsystem may jointly share beam splitter 106. The image acquisition subsystem and laser processing subsystem may be combined to reduce cost, size, and restoration time. In this respect, the restoration system 100 can be considered an integrated restoration and vision system.

[0042] The repair system 100 may include a light source 102. The light source 102 may be an illumination source. The light source 102 may generate illumination 103. Illumination 103 may include light of one or more selected wavelengths, including, but not limited to, vacuum ultraviolet (VUV), deep ultraviolet (DUV), ultraviolet (UV) radiation, visible radiation, or infrared (IR) radiation. Illumination 103 may include any range of selected wavelengths. In an embodiment, the light source 102 may include a spectrally tunable illumination source for generating illumination 103 with a tunable spectrum. Illumination 103 includes one or more optical properties. For example, the optical properties of illumination source 103 may include, but are not limited to, the angle of incidence, the angle of collection of illumination reflected from sample 115, one or more wavelengths, and the like.

[0043] The repair system 100 may include a beam splitter 104. The beam splitter 104 may be a beam combiner, splitter / combiner, or the like. In an embodiment, the light source 102 may guide illumination 103 to the beam splitter 104 via illumination path 105. Illumination 103 from the light source 102 can pass through the beam splitter 104. Illumination 103 may be coaxial after passing through the beam splitter 104. For example, the beam splitter 104 may combine illumination 103 from the light source 102 such that illumination 103 is coaxial with detector 116 and / or sample 115. Illumination 103 coaxial with detector 116 and / or sample 115 may be in a bright-field configuration. In an embodiment, the beam splitter 104 may make illumination 103 parallel to the optical axis of objective lens 112. Illumination 103 may be configured to pass through objective lens 112 to sample 115. Illumination 103 may be guided to sample 115 in a bright-field configuration. The beam splitter 104 can be oriented such that the light source 102 can simultaneously direct the illumination 103 to the sample 115 and enable the detector to collect the illumination reflected from the sample 115.

[0044] Although the restoration system 100 is described as including a beam splitter 104 and the illumination 103 is described as being coaxial or in a bright-field configuration, this is not intended to be a limitation of this disclosure. In embodiments, the restoration system 100 may include a light source 102a. The discussion of light source 102 is incorporated herein by reference to light source 102a. Light source 102a may produce illumination 103a. Illumination 103a may be off-axis. Illumination 103a may be directed to sample 115 in a dark-field configuration. The restoration system 100 may include a light source 102 that produces illumination 103 and / or a light source 102a that produces illumination 103a. Therefore, the restoration system 100 may include bright-field and / or dark-field configurations.

[0045] The repair system 100 may include a laser generator 108. The laser generator 108 may generate laser light 109. The laser generator 108 may be a pulsed laser generator and the laser light 109 may be a pulsed beam.

[0046] The laser beam 109 may include one or more optical properties. These optical properties may include, for example, the optical properties of the laser beam 109 manipulated by various optical elements of the restoration system 100 (e.g., objective lens 112, etc.) and / or the beam of the laser beam 109. For instance, the optical properties of the laser beam 109 may include spot size, energy density, waist position, beam profile, wavelength, Rayleigh length, energy, defocus, diameter, and the like.

[0047] The laser beam 109 may include a selected spot size. The spot size may also be a waist radius, spot area, focal point, ω0, or similar. The objective lens 112 can focus the laser beam 109 to the spot size. The spot size may be the minimum beam radius of the laser beam 109. The spot size may be located at the waist position. The beam radius of the laser beam 109 may increase away from the waist position.

[0048] The laser beam 109 may contain a selected energy density. The energy density may depend on the spot size and the laser energy. For example, the energy density may be the laser energy per unit area of ​​the spot size. The energy density may be highest at the waist position and may decrease as the beam cross-section increases away from the waist position. At the waist position, the peak energy density may be laterally located at the peak of the energy cross-section. For example, a Gaussian beam may have a peak energy density at the waist position (i.e., at the maximum value of the energy distribution). The energy density controls the depth to which the laser beam 109 ablates into the material. A laser with a higher energy density can ablate more material.

[0049] The laser beam 109 may include a selected waist position. The waist position may be the location of the minimum spot size. The dual-axis scanner 110 may allow the waist position to be rotated laterally.

[0050] The laser beam 109 may include a selected beam profile. The beam profile may include a tapered cross-section. In one embodiment, the laser beam 109 may have a Gaussian distribution. In another embodiment, the laser beam 109 may have a non-Gaussian distribution, such as a flat-top spot, a uniform intensity spot, or the like.

[0051] Laser light 109 may contain at least one wavelength. Laser light 109 may contain any wavelength, such as, but not limited to, 266 nm, 355 nm, 532 nm, 1064 nm, or the like. In embodiments, laser generator 108 may be a tunable laser generator. For example, laser generator 108 may tune laser light 109 between multiple wavelengths. Laser generator 108 may have tunable wavelengths. For example, laser generator 108 may be tuned within a range or selectable from a set of wavelengths (e.g., 1064 nm, 532 nm, 355 nm, 266 nm). Controller 118 may cause laser generator 108 to change the wavelength of laser light 109. Changing the wavelength of laser light 109 may change Rayleigh length, spot size, and the like. Changing the wavelength of laser light 109 does not affect the focusing of detector 116 and / or the properties of 2D image 117. If an optical element with high wavelength dependence is used in conjunction with a laser generator 108 having a tunable wavelength, then the tunable wavelength can be used to change the waist position of the laser beam 109.

[0052] The laser beam 109 may include a selected Rayleigh length. The Rayleigh length may be the distance from the waist position where the beam radius is smallest to the position where the radius of the laser beam 109 is increased by a multiple of 2 square roots.

[0053] The repair system 100 may include a dual-axis scanner 110. The dual-axis scanner 110 may be a dual-axis scanner, a dual-axis fast-turn mirror (FSM), a pair of single-axis galvanometer scanners, or the like. A laser beam 109 can pass through the dual-axis scanner 110. The dual-axis scanner 110 can redirect the laser beam 109 within a region of a defect on the sample 115. The dual-axis scanner can scan within a field of view. For example, the field of view may be a circle with a diameter of about 1 micrometer to 1000 micrometers or less. A controller 118 can provide control signals operated to manipulate the dual-axis scanner 110 to redirect the laser beam 109. The dual-axis scanner 110 can redirect the laser beam 109 in two dimensions (X and Y dimensions). The dual-axis scanner 110 may have independent control for X and Y positioning. The laser beam 109 can be redirected to illuminate defects placed on the sample 115, thereby performing laser repair operations, such as ablation of parasitic conductor deposits.

[0054] The repair system 100 may include a beam splitter 106. In an embodiment, a laser generator 108 may direct laser light 109 to the beam splitter 106. The laser light 109 may be directed to the beam splitter 106 via a laser path 111. The laser light 109 from the laser generator 108 may pass through the beam splitter 106. The beam splitter 106 may also combine the optical path of the laser light 109 with illumination 103 from the light source 102.

[0055] Repair system 100 may include objective lens 112. Objective lens 112 may include one or more optical elements, which may be reflective, refractive, or both. Objective lens 112 may include any suitable lens. In an embodiment, objective lens 112 may include an F-θ lens. Illumination 103 and laser light 109 may share objective lens 112. Illumination 103 and laser light 109 can pass through objective lens 112. Objective lens 112 may direct illumination 103 and laser light 109 onto sample 115. Specifically, objective lens 112 may direct laser light 109 onto defects on sample 115. The (partial) common optical path of illumination 103 and laser light 109 can be used to achieve accurate calibration and avoid positioning errors. Therefore, laser light 109 may be configured to pass through objective lens 112 to sample 115 to perform repair on defects located at defect location 123 on sample 115.

[0056] The repair system 100 may include a z-axis positioner 126. The z-axis positioner 126 may be coupled to an objective lens 112. The z-axis positioner 126 may change the position of the objective lens 112 along the z-axis. A controller 118 may cause the z-axis positioner 126 to change the position of the objective lens 112. The z-axis may be coaxial and / or orthogonal to the sample 115. For example, the height of the objective lens 112 relative to the sample 115 may be defined as its position along the z-axis. Changing the position of the objective lens 112 along the z-axis may shift the focal plane of the detector 116 (i.e., the sample height where the 2D image 117 is focused) and shift the position of the laser beam 109 relative to the waist of the sample 115.

[0057] The restoration system 100 may include an optical medium between the objective lens 112 and the sample 115. The optical medium may include any suitable optical medium, such as, but not limited to, air, immersion liquid (e.g., water, oil, etc.) and the like.

[0058] The repair system 100 may include a sample stage 114. The sample stage 114 may support a sample 115. The repair system 100 may be configured to translate various subsystems relative to the sample stage 114 and the sample 115. For example, the sample stage 114 may be configured to control the XY positioning of the sample 115 relative to illumination 103, illumination 103a, and / or laser light 109.

[0059] The sample stage 114 can control the Z-position of the sample 115 relative to illumination 103, illumination 103a, and / or laser beam 109. The repair system 100 may include a z-axis positioner 128. The z-axis positioner 128 is coupled to the sample stage 114. The z-axis positioner 128 can change the position of the sample 115 along the z-axis. The controller 118 can cause the z-axis positioner 128 to change the position of the sample 115. Changing the position of the sample 115 along the z-axis can shift the focal plane of the detector 116 (i.e., the sample height where the 2D image 117 is focused) and shift the position of the laser beam 109 relative to the waist of the sample 115.

[0060] Sample 115 may contain defects. Defects may include excess material defects (e.g., short-circuit defects) and / or missing material defects (e.g., open-circuit defects). Excess material defects may be excess conductive material (e.g., copper) or excess insulating material (e.g., substrate, solder resist, or solder mask). Defects may be protrusions, scratches, islands, short circuits, open circuits, and the like. Repair system 100 can be used to repair defects in sample 115. For example, laser beam 109 can ablate excess material defects to repair sample 115. Laser beam 109 can repair excess material defects by ablating excess solid material.

[0061] In an embodiment, the repair system 100 may include collected light 119. Illumination 103 and / or illumination 103a may be reflected or emitted from the defect location 123 of the sample 115 as collected light 119. Laser light 109 may also be reflected or emitted from the defect location 123 of the sample 115 as collected light 119. The collected light 119 reflected or emitted from the defect location 123 of the sample 115 may also include fluorescence emitted from the defect location 123 of the sample 115 after excitation by illumination 103, illumination 103a, and / or laser light 109. Illumination 103, illumination 103a, and / or laser light 109 may cause a portion of the defect location 123 of the sample 115 to fluoresce. Therefore, the collected light 119 may include specular reflection from coaxial illumination, diffuse reflection from off-axis illumination, reflected laser light, and / or fluorescence emitted from the defect location 123 of the sample 115 after excitation. The collected light 119 may differ from illumination 103, illumination 103a and / or laser light 109 in spectrum, optical power and / or direction.

[0062] The collected light 119 can be reflected or emitted from the defect location 123 of the sample 115 along the light collection path 113. The collected light 119 can be reflected or emitted from the sample 115 through the objective lens 112, beam splitter 106 and / or beam splitter 104. The collected light 119 can be reflected or emitted from the defect location 123 of the sample 115 to the detector 116.

[0063] The repair system 100 may include a detector 116. The detector 116 may be configured to capture collected light 119. In this respect, the detector 116 may receive collected light 119 reflected, emitted, or scattered (e.g., via specular reflection, diffuse reflection, and the like) from the defect location 123 of the sample 115. The detector 116 may be a camera. The detector 116 may include any type of optical detector suitable for measuring the light received from the sample 115. For example, the detector 116 may include, but is not limited to, a CCD detector, a TDI detector, a light multiplier tube (PMT), an avalanche photodiode (APD), a complementary metal-oxide-semiconductor (CMOS) sensor, or the like.

[0064] Detector 116 can be configured to generate a 2D image 117 of defect location 123 based on collected light 119. 2D image 117 may include a reflected image of defect location 123 of sample 115 or an image of fluorescence emitted by defect location 123 of sample 115. The reflected image may be, for example, an image of the defect scanned by laser light 109. Different reflected images may be acquired under different configurations of illumination 103, illumination 103a, and / or laser light 109. Fluorescent images can provide high contrast between a fluorescent substrate and a non-fluorescent conductor. For example, a fluorescent image may indicate an edge between copper and the substrate. The fluorescent image may be illuminated with violet or ultraviolet light, and the violet / UV light may be filtered to capture fluorescence from sample 115 instead of violet / UV light. Controller 118 can be configured to detect the edge between copper and the substrate. Controller 118 may use the edge between copper and the substrate to detect the 2D shape of the defect.

[0065] The repair system 100 may include a filter 134. The filter 134 may be disposed in a light-collecting path 113. For example, the filter 134 may be disposed in the light-collecting path 113 between the detector 116 and the beam splitter 104. The filter 134 may include, but is not limited to, a high-pass filter, a low-pass filter, a band-pass filter, and / or a notch filter. The filter 134 may be configured to filter the collected light 119. For example, the filter 134 may be configured to filter violet / UV light from the collected light 119, thereby allowing the detector 116 to capture fluorescence from the sample 115 instead of violet / UV light.

[0066] The repair system 100 may include a z-axis positioner 130. The z-axis positioner 130 may be coupled to a detector 116. The z-axis positioner 130 may change the position of the detector 116 along the z-axis. A controller 118 may cause the z-axis positioner 130 to change the position of the detector 116. Changing the position of the detector 116 along the z-axis may shift the focal plane of the detector 116 (i.e., the focus of the 2D image 117) but may not shift the waist position of the laser beam 109. The z-axis positioner 130 may be used in combination with z-axis positioners 126 and / or 128 to maintain the focus of the detector 116 while shifting the waist position of the laser beam 109. The z-axis positioner 130 may be used in combination with z-axis positioners 126 and / or 128 to change the focus of the detector 116 while maintaining the waist position of the laser beam 109 on the sample 115.

[0067] The repair system 100 can be configured to generate a 3D measurement 121. The 3D measurement 121 can be a three-dimensional measurement associated with the sample 115. The 3D measurement 121 can distinguish the height of the sample 115, also referred to as depth. For example, the 3D measurement 121 can include the height profile of defective regions on the sample 115. The height profile of the sample 115 can include the height of conductors, excess material defects, and / or substrate of the sample 115. The 3D measurement 121 may or may not distinguish the material of the sample 115. For example, the 3D measurement 121 may not distinguish between conductors, excess material defects, and substrate of the sample 115.

[0068] 3D measurement 121 may be generated within and / or outside the light-collecting path 113. 3D measurement 121 may or may not be based on the collected light 119. For example, 3D measurement 121 may be generated within the light-collecting path 113 based on the collected light 119. The restoration system 100 may be configured to generate 3D measurement 121 using focus ranging, interferometry, color confocal microscopy, or the like. As depicted, 3D measurement 121 is generated by the 3D camera 132 and received by the controller 118, although this is not intended to be limiting. Further consideration is that 3D measurement 121 may be generated by the controller 118 from a 2D image 117 using focus ranging.

[0069] In an embodiment, the restoration system 100 may be configured to use focus ranging to generate 3D measurements 121. The restoration system 100 may generate a stack of 2D images 117, wherein there is an inter-image offset of the focal plane between each pair of consecutive 2D images 117. The inter-image offset of the focal plane between the 2D images 117 may or may not be equal across all 2D images 117. The inter-image offset of the focal plane may decrease toward the substrate of the sample 115. For example, the inter-image offset of the focal plane between 2D image pairs 117 that are further away from the substrate may be larger and the inter-image offset of the focal plane between 2D image pairs 117 that are closer to the substrate may be smaller. Thus, higher resolution can be provided near the substrate. The restoration system 100 may control the offset of the focal plane of the 2D images 117 by moving the objective lens 112 using z-axis locator 126, moving the sample 115 using z-axis locator 128, and / or moving the detector 116 using z-axis locator 130. Pixels in a 2D image 117 focused at the depth of the focal plane can indicate the depth of pixels in a sample 115 (e.g., a conductor, excess material defect, or substrate of sample 115) at the focal plane. 3D measurements 121 can be generated from a stack of 2D images 117 with offset focal planes using focus ranging. Pixel depth estimation does not need to coincide with any of the focal planes of the stack of 2D images 117 and can be performed at depths across the various 2D images 117.

[0070] In an embodiment, the repair system 100 may be configured to use a 3D camera 132 to generate a 3D measurement 121. The repair system 100 may include a 3D camera 132. A controller 118 may cause the 3D camera 132 to generate the 3D measurement 121. The 3D camera 132 may include an interferometer, a confocal microscope (e.g., a color confocal microscope), or the like. For example, the interferometer may include a white light interferometer (WLI), a phase-shifting interferometer (PSI), a vertical scanning interferometer (VSI), a coherent scanning interferometer (CSI), a shearing interferometer, or the like. The 3D camera 132 may or may not share the illumination path 105, the laser path 111, the objective lens 112, the detector 116, and / or the light-collecting path 113. For clarity, a specific configuration in which the 3D camera 132 shares the illumination path 105, the laser path 111, and / or the light-collecting path 113 is not depicted.

[0071] 3D measurement 121 may have a 3D accuracy limit. The 3D accuracy limit may be the minimum depth at which 3D measurement 121 can be compared. The 3D accuracy limit may be based on the wavelength of the light used to generate 3D measurement 121. For example, the 3D accuracy limit may be a sub-wavelength of the light used to generate the 3D measurement. For example, the 3D accuracy limit may be a sub-wavelength of illumination 103, where 3D measurement 121 is generated from 2D image 117 (e.g., from collected light 119). 3D measurement 121 can detect depths above the 3D accuracy limit but may not be able to detect depths below the 3D accuracy limit. For example, 3D measurement 121 may have a 3D accuracy limit of 100 nanometers. 3D measurement 121 may be able to detect excess material defects on the substrate of sample 115 that are thicker than 100 nanometers, but the presence of minute short circuits between conductors with a thickness less than or equal to 100 nanometers cannot be ruled out. Using 3D measurement 121 during repair using laser light 109 may result in minute short circuits remaining between conductors. However, minor short circuits can be further repaired using 2D images 117, as will be further described in this article.

[0072] The repair system 100 may include a controller 118. The controller 118 may include one or more processors 122 configured to execute program instructions stored in memory 124. In this respect, the one or more processors 122 of the controller 118 may perform any of the various process steps described herein.

[0073] In an embodiment, memory 124 may contain a design file. The design file may represent the design to which sample 115 should be attached. The design file may contain design resolution for the lines. The design resolution may contain two-dimensional (2D) data about the lines. For example, the design resolution may contain line width. The design resolution may also contain three-dimensional (3D) data about the lines. For example, the design resolution may contain line thickness, also referred to as depth. The design file may also contain the thickness of the substrate. The design file may be exported from computer-aided manufacturing (CAM). The design file may be a CAM file or CAM data. The design file may contain a contour plot corresponding to the circuit to be tested, i.e., the edges between the conductors and the substrate. The design file may contain information about the cross-section of the conductors (e.g., the angle and / or ratio between the pattern lines and space).

[0074] Controller 118 can process design documents to understand the design content. Controller 118 can understand which parts of the design are wires, pads, paths, and the like. For example, controller 118 can measure the nearest neighbor conductor at each point in the design document. A coarser design may have a greater distance from the nearest neighbor conductor. A finer design may have a smaller distance from the nearest neighbor conductor.

[0075] In an embodiment, memory 124 may contain defect reports. Controller 118 may receive defect reports from an automated optical inspection (AOI) system or the like and store the defect reports in memory 124. The AOI system may be an upstream tool that can inspect sample 115 and determine the location of defect candidates. The defect report may also refer to an AOI report or the like. The defect report may contain the defect location 123 of one or more defects on sample 115. The defect report may contain repair assistance information, such as the type of defect, the number of laser pulses to be delivered, the laser energy density, and the like. Although the defect report is described as containing the number of laser pulses to be delivered and the laser energy density, this is not intended to be a limitation of this disclosure. The number of laser pulses to be delivered, the laser energy density, and the like may be part of a repair formulation.

[0076] Controller 118 is communicatively coupled to detector 116. Controller 118 can be configured to receive data including, but not limited to, 2D images 117, 3D measurements 121, and the like from detector 116. Controller 118 can cause detector 116 to generate a 2D image 117 of defect location 123 of one or more defects on sample 115. For example, controller 118 can cause detector 116 to generate a 2D image 117 of defect location 123 from a defect report at the defect location. Controller 118 can also generate 3D measurements 121. Controller 118 can cause repair system 100 to generate a 3D measurement of defect location 123 at the defect location. Controller 118 can cause repair system 100 to generate 3D measurements 121 from 2D images 117 by generating a stack of 2D images 117 with a focal plane offset and determining focus distance and / or using a 3D camera 132.

[0077] Repair system 100 can load a defect report, including the panel design and coordinates of the defect, into memory 124. Sample 115 can be loaded onto sample stage 114. Repair system 100 can proceed to defect location 123 on sample 115 based on the defect report. For example, repair system 100 can use an XY positioner to position objective lens 112 above defect location 123 and proceed to defect location 123 on sample 115. Repair system can use a combination of 2D image 117 and 3D measurement 121 at defect location 123 to perform closed-loop short-circuit repair. For example, repair system 100 can generate 3D measurement 121, ablate the 3D shape of excess material determined by 3D measurement 121 up to the 3D accuracy limit, generate 2D image 117 to identify residue below the 3D accuracy limit, and ablate the residue. Repair system can then proceed to the next defect in the defect report.

[0078] In one embodiment, the repair system 100 may include a user interface 120. The user interface 120 may be communicatively coupled to a controller 118. In one embodiment, the user interface 120 may include, but is not limited to, one or more desktop computers, laptop computers, tablet computers, and the like. In one embodiment, the user interface 120 may include a display for displaying data from the repair system 100 to a user. The display of the user interface 120 may include any display known in the art. For example, the display may include, but is not limited to, a liquid crystal display (LCD), an organic light-emitting diode (OLED) based display, or a CRT display. Those skilled in the art will recognize that any display device capable of being integrated with the user interface 120 is suitable for implementation in this disclosure. In another embodiment, a user may input selections and / or instructions in response to data displayed to the user via a user input device of the user interface 120.

[0079] Illumination path 105, laser path 111, and / or light-collecting path 113 may include additional optical components. These additional optical components may be adapted to modify and / or adjust illumination 103, illumination 103a, laser light 109, and / or collected light 119. For example, one or more optical components may include, but are not limited to, objective lens assembly 136, zoom actuator 138, aperture 140, variable beam expander 142, diffractive optical element 144, lens, polarizer, filter, beam splitter, diffuser, homogenizer, apodizer, shaper, shutter (e.g., mechanical shutter, electro-optic shutter, acousto-optic shutter, or the like), aperture stop, field stop, and the like. The repair system 100 may include any combination of optical components. For example, controller 118 can control any of the objective lens assembly 136, zoom actuator 138, aperture 140, variable beam expander 142 and / or diffractive optical element 144 to change the optical properties of illumination 103, laser light 109 and / or collected light 119 based on open-loop conditions (e.g., a predefined repair flowchart) or based on closed-loop conditions (e.g., feedback from 2D image 117 and / or 3D measurement during defect repair).

[0080] Objective lens assembly 136 may include multiple objectives 112. Objectives 112 may include magnification, numerical aperture, and the like. Objective lens assembly 136 may be modulated between objectives 112. Controller 118 may cause objective lens assembly 136 to be modulated between objectives 112 through which illumination 103 and / or laser light 109 and / or collected light 119 are configured. Modifying objectives 112 may refer to placing objectives 112 in the path of illumination 103 and / or laser light 109 and / or collected light 119. For example, objective lens assembly 136 may be rotatable between objectives 112, wherein objective lens assembly 136 is an objective lens mount. As another example, objective lens assembly 136 may be linearly translated between lenses 112, wherein objective lens assembly 136 includes a linear stage for objective lens assembly 136. Changing the objective lenses 112 can alter the field of view, image magnification, numerical aperture, image pixel size, image depth of field, Rayleigh length of the laser beam, spot size, and the like. The repair system 100 can then be modified between the objective lenses 112 to handle conductors with significantly different spacing between adjacent conductors.

[0081] In an embodiment, the repair system 100 may use multiple objectives 112. The repair system 100 may include a first objective for illumination 103 and a second objective for laser light 109. The first objective may be used for 3D measurement or to obtain a high-resolution 2D image 117. For example, the first objective may be used when obtaining a 3D measurement of a defect or when acquiring a 2D image 117 for accurate defect identification. The first objective may have a higher magnification than the second objective. Higher magnification is not desirable for repair because it reduces the laser spot size below a minimum size. Reducing the laser spot size below a minimum size can significantly decrease repair speed and increase energy density (e.g., penetration depth). In this respect, the resolution of the collected light 119 can be varied without changing the spot size of the laser light 109.

[0082] A zoom actuator 138 may be coupled to objective lens 112. The zoom actuator 138 may control the magnification of objective lens 112. A controller 118 may cause the zoom actuator to control the magnification of objective lens 112. For example, objective lens 112 may be a zoom objective lens. Changing the magnification of objective lens 112 may change the field of view, image magnification, numerical aperture, Rayleigh length, spot size, and the like. The zoom actuator 138 may include a zoom motor, an electric field generator, or the like. For example, objective lens 112 may change its magnification when an electric field is applied by the zoom actuator 138.

[0083] Aperture 140 may be positioned in the pupil plane or its conjugate plane of objective lens 112. Aperture 140 controls the numerical aperture of objective lens 112. Aperture 140 may be external to or internal to objective lens 112. When aperture 140 is internal to objective lens 112, objective lens 112 may be a variable aperture objective lens. Controller 118 may cause aperture 140 to change the aperture of objective lens 112. For example, controller 118 may use an actuator or the like to change the aperture of aperture 140. Changing the aperture of objective lens 112 changes image intensity, numerical aperture, Rayleigh length, spot size, and the like.

[0084] The variable beam expander 142 can change the diameter of the laser beam 109 and subsequently change the laser spot size, Rayleigh length, and the like. The controller 118 can cause the variable beam expander 142 to change the diameter of the laser beam 109. The variable beam expander 142 does not affect the focusing of the detector 116 and / or the properties of the 2D image 117.

[0085] Diffractive optical element 144 may be located within laser path 111. For example, diffractive optical element 144 may be located within laser path 111 between laser generator 108 and dual-axis scanner 110. Controller 118 may control diffractive optical element 144. For example, diffractive optical element 144 may be inserted into or removed from laser path 111. Diffractive optical element 144 may include a tunable phase element or the like. Diffractive optical element 144 may alter the beam profile of laser light 109. Controller 118 may cause diffractive optical element 144 to alter the beam profile of laser light 109. Altering the beam profile may improve ablation depth uniformity (e.g., using a top-cap profile) or prevent damage to the patterned conductor (e.g., using a Gaussian profile). Most applications prefer a Gaussian distribution. Diffractive optical element 144 may also transform the beam profile of laser light 109 into a non-Gaussian distribution. For example, diffractive optical element 144 may transform the beam profile into a flat-top spot or a uniform intensity spot. The diffractive optical element 144 does not affect the focusing of the detector 116 and / or the properties of the 2D image 117.

[0086] For reference Figure 2 Method 200 is described according to one or more embodiments of this disclosure. Method 200 may be a method for closed-loop short-circuit repair using a combination of 2D and 3D methods. The embodiments and implementation techniques previously described in the context of repair system 100 should be interpreted as extensions to this method. However, it should be further noted that the method is not limited to the architecture of repair system 100.

[0087] In step 210, the expected design at the defect location can be received. The expected design may include a two-dimensional and / or three-dimensional design at defect location 123. For example, the expected design may include a three-dimensional design with depth. Controller 118 may receive a design file for sample 115. The design file may be the expected design (e.g., a panel design). Controller 118 may also receive a defect report for the sample. Controller 118 may receive a defect report for sample 115 from an AOI system or similar. The defect report may include the defect location 123 on sample 115. The expected design may be a 3D measurement of the design, a model of the design, or the like.

[0088] In step 220, a top view of the 2D shape of the excess material defect at the defect location can be found by comparing the 2D image with the design. For example, 2D image 117 can be compared with the design document of sample 115 at defect location 123 to determine a top view of the 2D shape of the excess material defect. Repair system 100 can generate 2D image 117. Detector 116 can generate 2D image 117 at defect location 123. 2D image 117 may contain a panel image or the like. Controller 118 can identify the defect by comparing the actual pattern at defect location 123 in 2D image 117 with the expected pattern at defect location 123 in the design document. For example, controller 118 can identify the size (e.g., size (XY)) of the defect from the top view of the 2D shape of the excess material defect. Finding a top view of the 2D shape of the excess material defect can be an optional step. For example, 2D image 117 may or may not be captured. Although method 200 is described as finding a top view of a 2D shape, this is not intended to be a limitation of this disclosure. Finding a top view of the 2D shape is an optional step.

[0089] In step 230, a 3D measurement of the defect location can be generated. For example, the repair system 100 can be used to generate a 3D measurement 121 of the defect location 123. The 3D measurement may include the defect and / or one or more conductors adjacent to the defect location 123. The controller 118 may generate the 3D measurement 121 from multiple 2D images 117 and / or cause the 3D camera 132 to generate the 3D measurement 121.

[0090] In step 240, the 3D shape of the excess material defect can be determined by comparing the 3D measurement with the design. The 3D shape can be found by subtracting the design from the 3D measurement. The remainder after the subtraction can be the 3D shape of the excess material up to the limit of 3D accuracy. For example, controller 118 can determine the 3D shape of the excess material defect by comparing 3D measurement 121 with the design of sample 115 at defect location 123. The 3D shape of the defect can be the thickness at each XY pixel.

[0091] The 3D shape of excess material defects can be cut into multiple defect shapes. The defect shapes can be a stack of layers of 3D shapes of excess material defects to be removed. The defect shapes can be removed in one or more ablation cycles. The 3D shape can be cut into any integer number of defect shapes. The number of defect shapes can be based on the depth of the 3D shape of the defect and the ablation depth of the laser beam 109. A single 3D measurement 121 can produce defect shapes for ablation cycles up to the limit of 3D accuracy.

[0092] In step 250, the defect shape can be ablated by scanning the defect shape of the defect in the current layer with a laser beam. For example, excess material defects can be ablated by scanning the defect shape with laser beam 109. Laser beam 109 can ablate excess material defects at defect location 123 to remove the layer of excess material defects.

[0093] The repair system 100 can focus the laser beam 109 onto the excess material at the top of the excess material defect. The repair system 100 can determine the top of the excess material defect from its 3D shape. For example, the top of the defect can be determined from the highest focal plane where the defect is focused.

[0094] Similarly, the repair system 100 can determine the defect shape of the excess material defect from the 3D shape. For example, the 3D shape can be segmented into stacked defect shapes. The uppermost of the defect shapes can be ablated by scanning the laser beam 109 along the pattern of the defect shape. For example, the laser beam 109 can scan the uppermost defect shape in the stack of layers to remove the uppermost layer of the defect. The layers may correspond to the uppermost shape of the 3D shape of the excess material defect. As the laser beam 109 is directed by the dual-axis scanner 110 to scan along the layers, the repair system 100 can control the waist position of the laser beam 109. For example, the waist position of the laser beam 109 can be controlled in the XY plane. Scanning the laser beam 109 along the pattern of the defect shape can prevent the laser beam 109 from scanning portions of the defect below the current layer. The defect may not contain a uniform depth. Scanning portions of the defect below the current layer can cause the laser beam 109 to defocus at that location. When the laser beam is in the air, the laser beam 109 can be defocused and illuminate a larger area on the defect and / or cause the laser beam 109 to strike a reference conductor or substrate. Therefore, the repair system 100 can achieve speed and quality advantages by following a pattern that causes the laser beam 109 to scan according to the shape of the defect, rather than by scanning the laser beam 109 in the air above the next layer of the defect.

[0095] The repair system 100 achieves further speed advantages by combining XY scanning of the defect shape with real-time Z adjustment so that the removed layer follows the top surface of the defect instead of being planar. The repair system 100 can control the waist position of the laser beam 109 as it scans along the defect. For example, the controller 118 can guide the waist position, causing the laser beam 109 to follow the height profile of the defect. The repair system 100 can focus the waist position of the laser beam 109 to follow the height profile. Each pulse of the laser beam 109 can follow the height profile. Focusing the waist position of the laser beam 109 along the height profile reduces the number of pulses required for repair, resulting in a shorter repair time. Controlling the waist position while the laser beam 109 scans along the 3D profile can reduce the number of scans performed by the repair system 100, and similarly reduce the repair time.

[0096] The layer may contain a selected depth of excess material. The excess material can be ablated using a laser beam 109 with one or more optical properties. The optical properties determine the selected depth of the current ablation layer. The optical properties can be set according to the ablation formulation or the like.

[0097] The pattern of the laser beam 109 pulses can be performed sequentially or non-sequentially in the air. For example, the pattern of the pulses can be scanned sequentially. As another example, the pattern of the pulses can be non-sequentially guided by using an acousto-optic deflector that directs the pulses to different coordinates in a discontinuous manner. As used herein, scanning can refer to either sequentially or non-sequentially guided pulses. However, the pattern of the laser beam 109 pulses can be a defect shape.

[0098] In step 260, the laser beam can be refocused down to the next layer. For example, laser beam 109 can be refocused down to the next layer. Repair system 100 can refocus laser beam 109 down to the next layer for ablating excess material. Repair system 100 can then ablate the defect by removing one or more layers of excess material at the next layer.

[0099] The controller 118 can be configured to ablate a defect shape by scanning the laser beam 109 one or more times with the defect shape of the defect in the current layer before refocusing the laser beam 109 down to the next layer. For example, the controller 118 can ablate a defect shape by scanning the laser beam 109 once with the defect shape of the defect in the current layer before refocusing the laser beam 109 down to the next layer. As another example, the controller 118 can ablate a defect shape by scanning the laser beam 109 multiple times with the defect shape of the defect in the current layer before refocusing the laser beam 109 down to the next layer. The laser beam 109 can have a higher energy density when scanning the defect shape once before refocusing the laser beam 109 down to the next layer, and a lower energy density when scanning the defect shape multiple times before refocusing the laser beam 109 down to the next layer. A lower energy density of the laser beam 109 can help reduce debris caused by defect ablation.

[0100] Although controller 118 is described as refocusing laser beam 109 down to the next layer, this is not intended as a limitation of this disclosure. The controller can ablate the defect shape multiple times and perform repairs by altering other properties without refocusing on any layer. For example, controller 118 can perform multiple ablations while varying the energy density or spot size without refocusing. Therefore, the focal plane of laser beam 109 can be fixed while ablating multiple layers.

[0101] The repair system 100 ablates the 3D shape of the defect by repeatedly ablating the defect and refocusing the laser beam 109 down to the next layer. The repair system 100 can repeatedly guide the pulses of the laser beam 109 and refocus them to ablate the 3D shape determined from the 3D measurement 121. The repair system 100 can focus the laser beam 109 to perform multi-layer scanning of the laser beam 109 from the top of the excess material defect to ablate the 3D shape.

[0102] The controller 118 can determine the 3D shape of excess material that has been ablated using one or more open-loop and / or closed-loop conditions. For example, the controller 118 can use the energy density of the laser beam 109 as an open-loop condition to estimate the ablation depth at the current layer. The open-loop condition can be the ablation depth at the current layer estimated by the controller 118 using the energy density of the laser beam 109. The defect thickness (T) to be removed. The ablation area can be automatically adjusted according to the expected thickness removed in each iteration. The defect thickness (T) can be known from the 3D measurement 121. The pulse of the laser beam 109 can remove the thickness (t) of the excess material defect. The thickness (t) can be a function of the energy density and the spot size (which is itself a function of the waist size and defocus (if any)). The number of ablation cycles can be based on the defect thickness (T) and the thickness (t) removed in the current ablation layer. The defect thickness (T) is expected to be ablated over (n) iterations, where each iteration removes a thickness (t) such that n = T / t. The thickness (t) can vary for each coordinate within the defect region because the defect region can be non-planar, thus the laser spot size can be defocused at some coordinates. Since the defect profile is known from 3D measurement 121, the controller 118 can adjust (t) according to coordinates and estimate (n) according to coordinates, even for non-planar defects with different thicknesses and different defocuses. Ablation and defocus removal are performed by comparing the 3D measurement 121 initially determined before ablation with the 3D shape determined by the intended design. Therefore, the repair system 100 can ablate excess material defects and refocus down to the next working depth without generating additional 3D measurements 121. For example, no additional 3D measurements are generated when repeatedly ablating the defect shape in the current layer and refocusing the laser beam 109 down to the next layer.

[0103] In an embodiment, the repair system 100 may perform several scans at a given focal point before refocusing. For example, when the total removal depth at the focal position is less than an order of magnitude of the Rayleigh length of the laser beam 109, the repair system 100 may use the laser beam 109 to perform repeated ablation. Performing repeated scans between focal adjustments is expected to reduce the number of refocusing actions, thereby saving time and / or improving accuracy. When the total removal depth from the previous focal position is approximately the Rayleigh length of the laser beam 109, the repair system 100 may refocus the laser beam 109. For example, if the Rayleigh length is 2 μm and 0.5 μm of material is ablated, the repair system 100 may refocus the laser beam 109 every four ablations. Therefore, the laser beam 109 can be refocused as needed.

[0104] The 3D shape of a defect removed by ablation and refocusing may not encompass the entire defect. Residue from the defect may remain after ablation and refocusing to ablate the 3D shape from the defect. This residue may be below the 3D accuracy limit of 3D measurement 121. The residue may not be visible to 3D measurement 121. Performing additional 3D measurement 121 may fail to identify the residue. Additional 3D measurement 121 following an ablation cycle does not improve the 3D accuracy limit of 3D measurement 121. Repeated ablation and refocusing to ablate the 3D shape can ablate the defect up to the 3D accuracy limit. For example, the residue from the defect may be a fine short circuit. Therefore, repair using 3D measurement 121 may result in a fine short circuit.

[0105] In step 265, additional 3D measurements of the defect location may be generated. For example, the repair system 100 may be used to generate additional 3D measurements 121 of the defect location 123. The additional 3D measurements 121 may indicate whether the defect remains at the defect location or whether no defect remains at the defect location. If the 3D measurements 121 indicate that the defect remains at the defect location, the method may return to the step of determining the 3D shape of the defect. Generating the additional 3D measurements 121 of the defect location 123 may be an optional step.

[0106] In step 270, a 2D image of the defect location may be generated. For example, a 2D image 117 of defect location 123 may be generated. For example, controller 118 may cause detector 116 to generate 2D image 117. 2D image 117 may be a top view of the defect at defect location 123. 2D image 117 may contain residue of the defect below the 3D accuracy limit of 3D measurement. 2D image 117 may be acquired after one or more laser scans.

[0107] In step 280, the residue of the defect can be located by comparing the 2D image with the expected design at the defect location 123. For example, the residue of the defect can be located by finding the edge between the residue of the defect and the substrate in the 2D image 117. The edge can be compared with the edge in the expected design at the defect location 123. The residue of the defect can then be located by comparing the edge in the 2D image 117 with the edge in the expected design.

[0108] If additional 3D measurement 121 at defect location 123 indicates no residue at the defect location and the residue is found by comparing 2D images due to the defect height being below the 3D accuracy limit of 3D measurement 121, it can be determined that the height of the defect residue is below the 3D accuracy limit of 3D measurement 121. The energy density of the laser beam 109 can then be adjusted to ablate the thickness below the 3D accuracy limit of 3D measurement 121.

[0109] In step 290, the residue of the defect can be ablated by scanning the defect location with laser light based on a 2D image. For example, the residue of the defect can be ablated by scanning the defect location 123 with laser light 109 based on a 2D image 117. Regions near the substrate below the 3D accuracy limit can be ablated.

[0110] A portion of the defect residue may or may not remain after ablation of the defect residue. The repair system 100 may repeatedly generate 2D images 117 of the defect location 123, locate the defect residue, and ablate it. The repair system 100 may perform multiple scans of a laser beam 109 directed at the defect residue. The repair system 100 may focus the laser beam 109 on the defect residue. Additional 2D images 117 may be acquired after each scan. The repair system 100 may repeatedly acquire 2D images of the defect location, locate the defect residue, and ablate it until at least one criterion is met. The criterion may include determining that the defect has been repaired. For example, the controller 118 may determine that the defect has been repaired by detecting that the defect is no longer present at the defect location 123 in the 2D image 117 (e.g., from a fluorescence image). As another example, the controller 118 may determine that the defect residue is below an acceptable defect size. Therefore, the repair system 100 can use the 2D image 117 to induce laser light 109 to remove defects up to the substrate of the sample 115, as determined from the 2D image 117.

[0111] When repeatedly generating 2D images 117 of defect location 123, locating defect remnants, and ablating defect remnants, the repair system 100 may or may not refocus the laser beam 109 at different depths. For example, the repair system 100 may be unable to determine that the depth of the defect remnant is below the 3D accuracy limit, making refocusing impossible. Further consideration is that the repair system 100 may refocus the laser beam 109 based on open-loop feedback. Open-loop feedback may include refocusing the laser beam 109 based on the 3D accuracy limit from the top of the substrate and the ablation depth of the laser beam 109. For example, the laser beam 109 may be focused above the top of the substrate according to the 3D accuracy limit and then refocused on the next layer based on the ablation depth.

[0112] In an embodiment, the repair system 100 may repeatedly execute one or more steps of the method to repair a known defect (e.g., a defect in a defect report). For example, the repair system 100 may load a panel design (e.g., CAM) and the coordinates of the defect from a defect report. A sample 115 may be loaded onto a sample stage 114. The repair system 100 may then proceed to the defect coordinates of the defect in the defect report and execute the steps of the method to repair the known defect.

[0113] The repair system 100 can combine accuracy and speed using 2D images 117 and 3D measurements 121. Using 3D measurements 121 to perform scanning of the laser beam 109 up to the 3D accuracy limit, and then using 2D images 117 to perform scanning of the laser beam 109, can provide speed and / or accuracy improvements when repairing defects at defect location 123. The repair system 100 can use higher speeds when further repairing defect areas from the substrate. Starting with 3D measurements can save multiple cycles of imaging and processing time. For example, generating 3D measurements 121 can be slower than generating 2D images 117 on a per-measurement basis. However, one 3D measurement 121 can exist during the repair process compared to using multiple 2D images 117 to perform repair up to the 3D accuracy limit of the 3D measurements. The total time for generating 2D images 117 (image acquisition and calculation) can be longer than the total time for generating 3D measurements 121. Compared to methods such as using focus-based approaches to determine defect depth, calculating the edge between excess material and the substrate in 2D image 117 allows for computationally dense analysis. Repair system 100 also achieves high accuracy in defect regions close to the substrate. 2D image 117 provides high contrast for accurate identification of substrate defects near sample 115. Limited 3D accuracy can be addressed by acquiring fluorescence images at least at the end of the repair process to detect any minor short circuits and remove all unacceptable residues. By using information from 3D measurement 121 and 2D image 117, repair benefits from both time savings from 3D measurement 121 and accuracy from 2D image 117. Repair system 100 offers increased throughput compared to using only 2D image 117 to repair excess material defects. Repair system 100 offers increased accuracy compared to using only 3D measurement to repair excess material defects. 2D image 117 can be used to ablate residual defects with sensitivity lower than that of 3D measurement systems.

[0114] For reference Figures 3A to 3E According to one or more embodiments of this disclosure, an example of repairing a defect at defect location 123 of a sample using a combination of 2D and 3D repair methods is described. Defect location 123 may include a substrate 302, a conductor 304, and an excess material defect 306, or the like. The conductor 304 and the excess material defect 306 may be disposed on the substrate 302 of the sample 115. The conductor 304 may include a selected linewidth and a selected space width. The linewidth may refer to the width of the body 304. The space width may refer to the width of the space between the bodies 304. The excess material defect 306 may be disposed between the conductors 304. The excess material defect 306 may be a short circuit between the conductors 304. The conductors 304 and the excess material defect 306 may be formed of a conductive material (e.g., copper) or the like.

[0115] The repair system 100 can generate a 3D measurement 121. The 3D measurement 121 may include a substrate 302, a conductor 304, and an excess material defect 306. The 3D shape of the excess material defect can be determined by comparing the 3D measurement 121 with the expected design. The repair system 100 can determine a defect shape 308 to remove from the excess material defect 306. The defect shape 308 may include a defect polygon or the like. For example, the repair system 100 can determine defect shapes 308-1 to 308-m, where m is an integer. In the depicted example, six defect shapes 308 are determined from the 3D measurement 121, although this is not intended to be limiting. The sum of defect shapes 308-1 to 308-m may be the 3D shape determined from the 3D measurement 121.

[0116] Defect shape 308 indicates the shape of the excess material defect 306 removed when the excess material defect 306 is scanned with laser light 109 to ablate the excess material defect 306. Defect shape 308-1 indicates the uppermost defect shape to be ablated, and defect shape 308-m indicates the lowermost defect shape to be ablated. Because the area of ​​the excess material defect 306 changes along the depth of the excess material defect, the area of ​​defect shape 308 can change with ablation cycles. The area of ​​defect shape 308 can increase as defect shape 308 becomes closer to substrate 302. For example, defect shape 308-m closer to substrate 302 can have an area larger than defect shape 308-1.

[0117] Repair system 100 can generate laser light 109 and direct the laser light 109 to excess material defect 306. For example, repair system 100 can generate laser light 109 in multiple pulses (depicted as dashed lines). Repair system 100 can ablate the excess material defect 306 to which the laser light 109 is focused at the current layer. For example, the current layer can be in defect shape 308-m. Repair system 100 can ablate the shape of defect shape 308-m from excess material defect 306 with multiple pulses. Repair system 100 can then refocus laser light 109 on the next layer (e.g., defect shape 308-(m-1)) and ablate the next layer. Repair system 100 can continue to ablate and refocus defect shape 308-m to defect shape 308-1. Laser light 109 can ablate the 3D shape of excess material defect 306 determined from 3D measurement 121. Excess material defect 306 can be ablated up to the 3D accuracy limit of 3D measurement 121, leaving a residue after ablation. For example, defect shape 308-1 can be positioned at the 3D accuracy limit of 3D measurement 121. The residue of the defect can be below defect shape 308-1 and below the 3D accuracy limit of 3D measurement 121.

[0118] The repair system 100 can generate a 2D image 117. The 2D image 117 may contain residue of the excess material defect 306. The repair system 100 can ablate the residue of the excess material defect 306 based on the 2D image 117. The repair system 100 can repeatedly generate the 2D image 117 and ablate the residue of the excess material defect 306 based on the 2D image 117 until the excess material defect 306 has been repaired. For example, in Figure 3E In the image 117, the 2D image can indicate that the residue of the excess material defect 306 is below the allowable defect size, thus the excess material defect 306 has been repaired.

[0119] Referring again generally to the figures. In this embodiment, controller 118 may be configured to alter one or more optical properties of illumination 103, illumination 103a, laser light 109, and / or collected light 119 based on feedback from 2D image 117 of detector 116. Controller 118 may alter one or more components of illumination path 105, laser path 111, and / or light collection path 113 to change the optical properties of illumination 103, illumination 103a, laser light 109, and / or collected light 119. For example, controller 118 may control the optical properties of laser light 109 to change spot size, energy density, waist position, beam profile, wavelength, Rayleigh length, and the like. The controller 118 can alter the optical properties of the laser light 109 by vertically moving the objective lens 112, changing the zoom setting of the objective lens 112, changing the objective lens 112, changing the numerical aperture of the objective lens 112, changing the beam diameter of the laser light 109, changing the spot energy profile of the laser light 109, changing the wavelength of the laser light 109, or similar methods. Similarly, the controller 118 can control the optical properties of the illumination 103, illumination 103a, and / or the collected light 119, such as field of view, focus, and similar methods. The controller 118 can alter the optical properties of the illumination 103, illumination 103a, laser light 109, and / or the collected light 119 during defect repair.

[0120] In an embodiment, controller 118 may identify the most minute features of the design of sample 115. Controller 118 may identify these minute features through a process such as computer-aided manufacturing (CAM) learning. In an embodiment, controller 118 may be configured to modify the optical properties of laser light 109 based on the most minute features of sample 115. Although controller 118 is described as setting the optical properties of laser light 109 based on the most minute features of sample 115, this is not intended to be a limitation of this disclosure.

[0121] In one embodiment, the controller 118 may alter the optical properties of the laser beam 109 during defect repair of the sample 115. For example, the controller 118 may alter the optical properties of the laser beam 109 during the repair of the sample 115 based on the size of the defect in the 2D image 117. As another example, the controller 118 may preset the optical properties of the laser beam 109 based on the expected size of the defect at defect location 123 according to the design resolution in the design document.

[0122] In embodiments, the restoration system 100 may configure one or more of the optical properties of the laser beam 109 on a pulse-by-pulse basis. For example, the restoration system 100 may configure energy, defocus, and / or diameter on a pulse-by-pulse basis. For example, a laser spot guided to be adjacent to a “reference” conductor may have a different energy than a laser spot guided to be further away from the “reference” conductor. In embodiments, the restoration system 100 may perform per-spot focusing. The restoration system 100 may perform per-spot focusing by moving the objective lens 112, moving the sample 115, using variable-focus optics, and the like. Configuring optical properties on a pulse-by-pulse basis may involve changing the properties at each pulse, every other pulse, or at a slower rate.

[0123] In an embodiment, the repair system 100 may repeatedly configure one or more of the optical properties of the laser light 109 during defect repair. The repair system 100 may deliver the laser light 109 to the defect location 123. The energy density of the laser light 109 may be selected such that the laser light 109 does not damage the substrate of the sample 115, even if the laser light 109 does not completely remove the excess material after it is initially applied to the excess material. After the initial repair operation is completed, the repair system 100 may acquire an additional 2D image 117 of the defect location 123. For example, the repair system 100 may acquire the 2D image 117 of the defect location 123 after performing ablation based on 3D measurement 121. The repair system 100 may determine, based on the 2D image 117, that a portion of the defect still exists at the defect location 123. For example, the repair system 100 may determine that a portion of the defect exists at the defect location 123 in the 2D image 117 (e.g., from a fluorescence image). The repair system 100 can adjust the optical properties of the laser beam 109 and use the adjusted optical properties to deliver the laser beam 109 to the defect location 123. Adjusting the optical properties may include reducing the energy density of the laser beam 109. Reducing the energy density of the laser beam 109 can help reduce the likelihood of laser damage to the substrate 302. The process of verifying the presence of the defect, adjusting the optical properties, and automatically performing the repair operation can be repeated until the controller 118 determines that the defect has been repaired. The controller 118 can determine that the defect has been repaired by detecting that the defect is no longer present at the defect location in a 2D image 117 (e.g., from a fluorescence image). Upon determining that the defect has been repaired, the repair system 100 can reposition itself to the next defect location 123.

[0124] While this disclosure is largely intended to repair excess material defects, it is not intended to be a limitation thereof. The repair system 100 may also repair lost material defects. The repair system 100 may include material application hardware for repairing lost material defects. The material application hardware may include chemical vapor deposition (CVD) hardware, solid or liquid application hardware, laser-induced forward transfer (LIFT), inkjet, or other guided material deposition systems. The repair system 100 may perform various repair operations. Repair operations include, for example, ablation of parasitic portions of a conductor, removal of oxides formed on conductor portions, and / or processes for locally depositing additional conductor material or additional substrate material. The additional conductor material may be deposited and then irradiated by laser light 109 to connect the additional conductor material to a printed circuit. Although not depicted, the repair system may also include functionality for depositing conductor portions at defect locations 123 where a portion of the conductor is lost or deformed, and / or functionality for depositing substrate portions at locations where a portion of the substrate is lost or deformed. For example, the repair system may include an inkjet device.

[0125] One or more processors may comprise any processor or processing element known in the art. For the purposes of this disclosure, the terms “processor” or “processing element” may be broadly defined to cover any device having one or more processing or logic elements (e.g., one or more microprocessor devices, one or more application-specific integrated circuit (ASIC) devices, one or more field-programmable gate arrays (FPGAs), or one or more digital signal processors (DSPs)). In this sense, one or more processors may comprise any device configured to execute algorithms and / or instructions (e.g., program instructions stored in memory). In one embodiment, one or more processors may embody a desktop computer, a host computer system, a workstation, a graphics computer, a parallel processor, a networked computer, or any other computer system configured to execute a program. Furthermore, different subsystems of the system may contain processors or logic elements suitable for performing at least a portion of the steps described in this disclosure. Therefore, the foregoing description should not be construed as limiting the embodiments of this disclosure but is merely illustrative. Moreover, the steps described throughout this disclosure may be performed by a single controller or alternatively by multiple controllers.

[0126] In embodiments, the controller may comprise one or more controllers housed within a common housing or multiple housings. In this way, any controller or combination of controllers can be individually packaged as a module suitable for integration into a system. For example, the controller may analyze data received from a detector and feed the data to additional components inside or outside the system.

[0127] The memory may comprise any storage medium known in the art suitable for storing program instructions executable by one or more associated processors. For example, the memory may comprise non-transitory memory. As another example, the memory may comprise, but is not limited to, read-only memory (ROM), random access memory (RAM), magnetic or optical storage devices (e.g., magnetic disks), magnetic tape, solid-state drives, and the like. It should be further noted that the memory may be housed together with one or more processors in a common controller housing. In one embodiment, the memory may be remotely located relative to the physical location of one or more processors and the controller. For example, one or more processors of the controller may access remote memory (e.g., a server) accessible via a network (e.g., the Internet, an intranet, and the like).

[0128] As used throughout this disclosure, the term "sample" generally refers to a substrate formed of a semiconductor or non-semiconductor material (e.g., thin-film glass, ceramic, organic laminate, or the like). For example, semiconductor or non-semiconductor materials may include, but are not limited to, single-crystal silicon, gallium arsenide, indium phosphide, organic substrates (e.g., Ajinomoto deposited film (ABF)), or glass materials. A sample may contain one or more layers. For example, such layers may include, but are not limited to, resists (including photoresists), dielectric materials, conductive materials, and semiconducting materials. Many different types of such layers are known in the art, and the term "sample" as used herein is intended to cover samples on which all types of such layers can be formed. The one or more layers formed on a sample may be patterned or unpatterned. For example, a sample may contain multiple dies, each having repeatably patterned features. The formation and processing of such material layers can ultimately result in a finished device. Many different types of devices can be formed on a sample, and the term "sample" as used herein is intended to cover samples on which any type of device known in the art is manufactured. Furthermore, for the purposes of this disclosure, the terms sample, panel, and wafer should be interpreted as interchangeable. Additionally, for the purposes of this disclosure, the terms patterning apparatus, mask, and photomask should be interpreted as interchangeable.

[0129] Furthermore, upon further consideration, each of the embodiments of the methods described above may include any other step of any other method described herein. Additionally, each of the embodiments of the methods described above may be performed by any of the systems described herein.

[0130] Those skilled in the art will recognize that, for the sake of clarity, the components, operations, devices, objects, and accompanying discussions described herein are used as examples and various configuration modifications may be considered. Therefore, the specific examples and accompanying discussions used herein are intended to represent their more general categories. In general, the use of any specific example is intended to represent its category, and the omission of specific components, operations, devices, and objects should not be considered limiting.

[0131] As used herein, directional terms such as “top,” “bottom,” “above,” “below,” “up,” “upward,” “down,” “facing downward,” and “downward” are intended to provide relative positions for descriptive purposes and are not intended to specify an absolute frame of reference. Those skilled in the art will understand that various modifications to the described embodiments are possible, and that the general principles defined herein can be applied to other embodiments.

[0132] Regarding the use of virtually any plural and / or singular terms in this document, those skilled in the art can translate plural to singular and / or singular to plural depending on the context and / or application. For clarity, various singular / plural arrangements are not explicitly described herein.

[0133] The topics described herein sometimes refer to different components contained within or connected to other components. It should be understood that such depicted architectures are merely exemplary, and in fact, many other architectures can be implemented to achieve the same functionality. Conceptually, any arrangement of components used to achieve the same functionality is effectively “associated” to achieve the desired functionality. Therefore, any two components combined herein to achieve a particular functionality can be considered “associated” with each other to achieve the desired functionality, regardless of the architecture or intermediate components. Similarly, any two such associated components can also be considered “connected” or “coupled” with each other to achieve the desired functionality, and any two components that can be suchly associated can also be considered “coupleable” with each other to achieve the desired functionality. Specific examples of coupleability include, but are not limited to, physically hybrid and / or physically interactive components and / or wirelessly interactive and / or logically interactive components.

[0134] Furthermore, it should be understood that the invention is defined by the appended claims. Those skilled in the art will understand that, generally, the terms used herein, and especially in the appended claims (e.g., the body of the appended claims), are generally intended as “open-ended” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “at least having,” the term “includes” should be interpreted as “including but not limited to,” and so on). Those skilled in the art will further understand that if it is intended to introduce a specific number of claim statements, then this intention will be explicitly stated in the claims, and if such a statement is not present, then this intention does not exist. For example, as an aid to understanding, the appended claims may contain the use of the introductory phrases “at least one” and “one or more” to introduce claim statements. However, the use of such phrases should not be construed as implying that the introduction of a claim statement by the indefinite article “a(a)” or “an” limits any particular claim containing such an introduction to an invention containing only one such statement, even if the same claim contains the introductory phrase “one or more” or “at least one” and indefinite articles such as “a(a)” or “an” (e.g., “a(a)” and / or “an” should generally be interpreted as “at least one” or “one or more”); the same applies to the use of definite articles used to introduce a claim statement. Furthermore, even if a specific number of claim statements is explicitly stated to be introduced, those skilled in the art will recognize that such a statement should generally be interpreted as indicating at least the number stated (e.g., a bare statement of “two statements” without other modifiers generally indicates at least two statements or two or more statements). Furthermore, in examples where the convention of "at least one of A, B, and C and similar" is used, this construction is generally intended to be understood by those skilled in the art (e.g., "a system having at least one of A, B, and C" includes, but is not limited to, systems having only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C, and similar systems). In examples where the convention of "at least one of A, B, or C and similar" is used, this construction is generally intended to be understood by those skilled in the art (e.g., "a system having at least one of A, B, or C" includes, but is not limited to, systems having only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C, and similar systems). Those skilled in the art should further understand that virtually any extractive terms and / or phrases presenting two or more alternatives, whether in the detailed description, claims, or drawings, should be understood to contemplate the possibility of including one, two, or both of the stated terms.For example, the phrase “A or B” should be understood as including the possibility of “A” or “B” or “A and B”.

[0135] It is believed that this disclosure and its many accompanying advantages will be understood from the foregoing description, and it should be understood that various changes can be made to the form, construction, and arrangement of the components without departing from the disclosed subject matter or without sacrificing all its substantial advantages. The described forms are merely illustrative, and the following claims are intended to cover and encompass such changes. Furthermore, it should be understood that the invention is defined by the appended claims.

Claims

1. A repair system comprising: A light source, configured to produce illumination; A laser generator configured to produce laser light; A dual-axis scanner configured to redirect the laser beam; A sample stage, configured to support the sample; An objective lens, wherein the laser light is configured to pass through the objective lens to the sample to perform repair on a defect located at a defect site on the sample; A detector configured to generate a 2D image of the defect location based on collected light, wherein the collected light is reflected or emitted from the defect location, passes through the objective lens to the detector; and A controller includes one or more processors configured to execute program instructions stored in memory, the program instructions causing the controller to: 3D measurement of the defect location is generated; The 3D shape of the defect is determined by comparing the 3D measurements with the expected design of the defect location; The 3D shape of the defect is ablated by repeatedly performing the following operations: The defect shape is ablated by scanning the defect shape in the current layer with the laser light; Generate the 2D image; Locate any remnants of the defect in the 2D image; and The residue from the ablation of the defect.

2. The repair system of claim 1, wherein focusing rangefinding is used to generate the 3D measurement.

3. The restoration system of claim 2, wherein the detector is configured to generate a plurality of 2D images having an inter-image offset in a focal plane; wherein the 3D measurement is generated from the plurality of 2D images.

4. The restoration system of claim 3, wherein the inter-image offset in the focal plane decreases toward the substrate of the sample.

5. The repair system of claim 1, comprising a 3D camera; wherein the controller is configured to cause the 3D camera to generate the 3D measurement.

6. The repair system of claim 1, wherein the program instructions cause the controller to segment the 3D shape into a plurality of defect shapes stacked together.

7. The repair system of claim 1, wherein the program instructions cause the controller to determine that the 3D shape has been ablated using open-loop conditions.

8. The repair system of claim 7, wherein the open-loop condition is the ablation depth at the current layer estimated by the controller using the energy density of the laser light.

9. The repair system of claim 7, wherein the repair system ablates the 3D shape without generating additional 3D measurements.

10. The repair system of claim 1, wherein the residue of the defect is below the 3D accuracy limit of the 3D measurement.

11. The repair system of claim 1, wherein the program instructions cause the controller to repeatedly generate the 2D image of the defect location, locate the residue of the defect, and ablate the residue of the defect.

12. The repair system of claim 11, wherein the program instructions cause the controller to repeatedly generate the 2D image of the defect location, locate the residue of the defect, and ablate the residue of the defect until the controller determines that the residue of the defect is below an allowable defect size.

13. The repair system of claim 11, wherein the program instructions cause the controller to refocus the laser light at different depths while repeatedly generating the 2D image of the defect location, locating the residue of the defect, and ablating the residue of the defect.

14. The repair system of claim 1, wherein the defect is an excess material defect; wherein the laser light repairs the excess material defect by ablating the excess material defect.

15. The repair system of claim 1, wherein the memory stores design files and defect reports, wherein the design files include the intended design.

16. The repair system of claim 1, wherein the collected light reflected from the sample includes light emitted by the sample after being excited by at least one of the illumination or the laser light.

17. The restoration system of claim 1, wherein the illumination is directed to the sample in a bright field configuration; wherein the illumination and the laser light are configured to pass through the objective lens to the sample.

18. The repair system of claim 1, wherein the illumination is guided to the sample according to a dark field configuration.

19. The repair system of claim 1, wherein the controller is configured to ablate the 3D shape of the defect by repeatedly performing the following operations: The defect shape is ablated by scanning the defect shape in the current layer with the laser light; and The laser beam is then refocused downwards onto the next layer.

20. The repair system of claim 19, wherein the controller is configured to ablate the defect shape by scanning the defect shape of the defect in the current layer once with the laser light before refocusing the laser light down to the next layer.

21. The repair system of claim 19, wherein the controller is configured to ablate the defect shape by scanning the defect shape of the defect in the current layer multiple times before refocusing the laser light down to the next layer.

22. The repair system of claim 19, wherein the controller is configured to ablate the defect shape by causing the laser light to scan the defect shape of the defect in the current layer multiple times, without refocusing the laser light down to the next layer.

23. The repair system of claim 1, wherein the controller is configured to: Generate additional 3D measurements of the defect location, wherein the additional 3D measurements indicate that the defect is still at the defect location; The 3D shape of the defect is determined from the additional 3D measurements; and The 3D shape of the defect is ablated.

24. A method comprising: 3D measurement of the defect location is generated, wherein the defect is located at the defect location on the sample; The 3D shape of the defect is determined by comparing the 3D measurements with the expected design of the defect location; The 3D shape of the defect is ablated by repeatedly performing the following operations: The defect shape is ablated by scanning the defect shape in the current layer with laser light; Generate 2D images; Locate any remnants of the defect in the 2D image; and The residue from the ablation of the defect.

Images