Substrate positioning for deposition machine

Abstract

A deposition apparatus is described. A deposition apparatus has a substrate support and a laser imaging system disposed to image a portion of a substrate located on the substrate support. The laser imaging system includes a laser source and an imaging unit, and the laser imaging system is coupled to a deposition assembly disposed across a substrate support.

Description

Cross-reference to related applications

[0001] This application claims priority to U.S. Provisional Patent Application Serial No. 62 / 872,501, filed July 10, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Embodiments of the present invention generally relate to deposition apparatuses. Specifically, a deposition apparatus having an attached but movable operating table is described. Background Technology

[0003] Inkjet deposition is common in office and home printers, as well as in industrial printers used for manufacturing displays, depositing large written materials, incorporating materials into finished products such as printed circuit boards, and constructing biological products such as tissues. Most commercial or industrial inkjet deposition machines, and some consumer printers, employ a dispenser to apply material to a substrate. The dispenser jets a controlled amount of deposited material onto the substrate at a controlled time and speed so that the deposited material reaches the target location on the substrate and forms a mark of the desired size and shape.

[0004] In some applications, such as in the display manufacturing industry, very high-precision deposition is achieved by depositing minute amounts of material in extremely precise locations. In some cases, the volume can be as small as 10 μm, deposited in areas as small as 15 μm. To achieve this level of placement accuracy on the substrate, the substrate must be precisely positioned and / or its exact location must be known. Camera-based vision systems are typically used to photograph the substrate and pinpoint its location, but image acquisition and processing are very time-consuming. Therefore, a better method is needed to precisely determine the position of substrates used in inkjet printing. Summary of the Invention

[0005] The embodiments described herein provide a deposition apparatus including: a substrate support; and a deposition assembly including a laser imaging system disposed on the substrate support.

[0006] Other embodiments described herein provide a method for imaging a feature on a substrate, comprising: scanning the substrate relative to a laser imaging system including a laser source and an imaging unit; activating the imaging unit before an end of the feature reaches an illumination field of the laser source; activating the laser source when a portion of the feature reaches the illumination field; turning off the laser source after an activation time; and turning off the imaging source after an imaging time, wherein the imaging time includes the activation time.

[0007] Other embodiments described herein provide a deposition apparatus including a substrate support and a deposition assembly including a laser imaging system disposed on the substrate support. The laser imaging system includes: a laser source fiber coupled to an optical assembly to guide laser radiation from a laser source to the substrate support; and an imaging unit configured to acquire laser radiation reflected through the optical assembly. Attached Figure Description

[0008] To gain a more detailed understanding of the features described above, reference can be made to embodiments that provide a more specific description of the disclosure, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only exemplary embodiments and should not be construed as limiting their scope; other equivalent embodiments are permissible.

[0009] Figure 1 This is an isometric top view of a deposition apparatus according to one embodiment.

[0010] Figure 2 This is a block diagram of a location acquisition system according to one embodiment.

[0011] Figure 3 This is an algorithm diagram of an ink droplet ejection algorithm according to one embodiment.

[0012] Figure 4 This is a flowchart of the method according to one embodiment.

[0013] Figure 5 This is a flowchart of a method that can be used with the apparatus described herein and other methods.

[0014] Figure 6 This is an isometric top view of a deposition apparatus according to another embodiment.

[0015] For ease of understanding, the same reference numerals are used where possible to denote common elements in the figures. It is conceivable that elements and features in one embodiment can be directly used in other embodiments without further detail. Detailed Implementation

[0016] The deposition apparatus described herein has an operating table that can be configured above the worktable of the deposition apparatus and stored at a height at least partially below a reference elevation of the worktable near its end to allow for substrate loading and unloading. Figure 1This is an isometric top view of a deposition apparatus 100 according to one embodiment. The deposition apparatus has a base support 102, a deposition assembly 104, and a retainer assembly 106 for manipulating the deposition base. The deposition apparatus 100 includes a base 108, which is typically a large object to minimize vibration transmission to the actuators of the deposition apparatus 100. In one example, the base 108 is a granite block. The deposition assembly 104 includes a deposition assembly support 116, which includes supports 120 located on each side of the base 108 and guide rails or beams 117 extending across the base support 102 between the supports 120.

[0017] The substrate support 102 has a first portion 102A, a second portion 102B, and a third portion 102C located between the first and second portions 102A and 102B. The first and second portions 102A and 102B are transit areas for substrate entry and exit from the deposition apparatus 100, while the third portion 102C is a working area for positioning the substrate to be treated relative to the deposition assembly support 116. The substrate support 102 has a worktable 110 and means for making the worktable 110 substantially frictionless. Here, the worktable 110 is an air cushion platform that provides an air cushion function, such as air, oxygen-free air, dry air, nitrogen, or other suitable gas that allows the substrate to float on it. The worktable 110 is characterized by having a plurality of holes (not shown) that allow gas jets to exit, thereby providing an upward force to hold the substrate at a desired height above the worktable 110. Some of the holes also allow controlled extraction of gas from the air cushion floating on the substrate support, thereby precisely and locally controlling the height of the substrate. In one embodiment, the third part 102C has an air supply port and an air extraction port. The air supply port and the air extraction port independently control the gas in the air cushion, thereby controlling the floating height of the base above the base worktable 110.

[0018] The deposition assembly 104 includes a distributor assembly 114 coupled to a crossbeam 117. The distributor assembly 114 includes a distributor housing 119 coupled to a deposition carriage 122, which travels along the crossbeam 117 to position the distributor assembly 114 relative to a substrate disposed on a third portion 102C of the substrate support 102. The distributor housing 119 contains one or more distributors (not shown) that spray a quantity of deposited material onto the substrate located on the substrate support 102 below the deposition assembly 104.

[0019] The substrate is positioned below the deposition assembly 104 by a retainer assembly 106. The retainer assembly 106, upon loading, firmly contacts the substrate and moves the substrate along the substrate support 102 to position the substrate relative to the deposition assembly 104, thereby precisely dispensing printing material onto the substrate. In this configuration, the retainer assembly 106 typically extends along the substrate support 102 in a first direction to translate the substrate in that direction during deposition. Figure 1 In the diagram, the first direction is indicated by arrow 124. The dispenser assembly 114 generally moves in a second direction substantially perpendicular to the first direction, as defined by a crossbeam 117 extending substantially in the second direction. Figure 1 The direction 126 is indicated by arrow 126. The second direction 126 is sometimes referred to as the "x direction", while the crossbeam 117 is referred to as the "x beam".

[0020] Controller 132 is operatively coupled to fixture assembly 106 and deposition assembly 104 to control the movement of a substrate positioned on a substrate support and the deposition on the substrate. Controller 132 may directly control the actuators of fixture assembly 106 and deposition assembly 104, or controller 132 may be operatively coupled to a fixture assembly controller coupled to fixture assembly 106 and a deposition assembly controller coupled to deposition assembly 104. Controller 132 controls the movement and positioning of the substrate (if any) on substrate support 102. Controller 132 also controls the movement of distributor assembly 114 along crossbeam 117 and the spraying of deposited material from distributor assembly 114 onto the substrate.

[0021] Laser imaging system 150 is coupled to distributor assembly 114. Laser imaging system 150 includes a laser source 152 and an imaging unit 154. Laser source 152 directs laser radiation onto a substrate located on a substrate support 102 below distributor assembly 114. Imaging unit 154 detects the laser radiation reflected by the substrate. Imaging unit 154 may include a digital camera or other high-precision imaging acquisition component. Imaging unit also includes optics for focusing the radiation onto the imaging acquisition component. Laser source 152 and imaging unit are configured such that laser source 152 provides an illumination field on the substrate, wherein the substrate is located within the imaging field of imaging unit 154.

[0022] Laser source 152 can emit laser radiation selected to minimize its impact on other aspects of deposition apparatus 100 and the processes performed by deposition apparatus 100. For example, in many cases, deposition apparatus 100 is used to deposit curable materials onto a substrate. Such materials are typically cured using short-wavelength electromagnetic radiation, such as ultraviolet radiation. These materials are sensitive to short-wavelength visible light radiation in terms of frequency, and less sensitive to longer-wavelength visible light radiation. Since uniform processing is important for achieving high precision in industries such as display manufacturing, a laser source emitting long-wavelength radiation can be selected to minimize the impact on the deposited material. For this purpose, laser sources emitting wavelengths of 650 nm or higher are practical. In one example, the laser source has an emission wavelength of 650 nm. In another example, the laser source has an emission wavelength of 800 nm. The laser source can be a laser diode, or an assembly of laser diodes, such as a laser diode bar. A combination of laser source and imaging acquisition component can also be selected to maximize the sensitivity of the imaging acquisition component to the radiation emitted by the laser source. For example, the Dalsa Nano M2020 camera has near-peak sensitivity at a wavelength of 650 nm. Silicon-based NIR imaging acquisition units typically have peak sensitivity around 800 nm.

[0023] In this configuration, the laser source 152 is fiber-coupled to direct laser radiation to an emitting plane that can be positioned close to the substrate. Therefore, the divergence of the laser radiation can be managed to produce an illumination field of the desired size. For many display applications, the substrate has positioning features, such as reference markers, which can be used to precisely calibrate the substrate's position. These markers can be very small, such as 1-5 mm in size. In some cases, the markers are cross-shaped. Fiber coupling allows the radiation emitting plane to be positioned such that the divergence of the radiation produces a spot of light that contains all or most of the field of view needed to determine the marker's position.

[0024] The laser imaging system 150 is configured to acquire images as the substrate and distributor assembly 114 move relative to each other. In some cases, the relative motion can be as fast as 1 m / sec. An imaging controller 158 is operatively coupled to the laser source 152 and the imaging acquisition unit 154 to drive image acquisition while the relative movement is in progress. Here, the laser source has a pulse capability of at least 5 μsec, meaning that the average intensity of the emitted radiation field increases, reaches half of its maximum value at the pulse start time, then decreases, reaches half of its maximum value at the pulse end time, and within one pulse duration, defined as the duration from the pulse start time to the pulse end time, is approximately 5 μsec. In some cases, a laser source with a pulse capability of at least 1 μsec is used. The imaging controller 158 is implemented in a printed circuit board containing digital circuitry that transmits commands to the imaging acquisition unit 154 to start and stop image acquisition, and to the laser source 152 to turn on and off, or alternatively, to emit pulses with a defined duration. Imaging controller 158 is operatively coupled to controller 132 and optionally coupled to other controllers, such as fixator assembly controllers and distributor assembly controllers, to send and receive signals representing information for controlling substrate imaging. Imaging controller 158 is configured to send image signals representing images acquired by imaging acquisition unit 154 to controller 132 for analysis. When features of the substrate (such as positioning features) are expected to be within the field of view of imaging acquisition unit 154, imaging controller 158 is also configured to control imaging acquisition unit 154 and laser source 152 to acquire images based on information received from controller 132, such as the expected location of the features and the speed of movement of the substrate.

[0025] Figure 2 This is a front view of a position acquisition system 200 according to one embodiment. The position acquisition system 200 includes a laser imaging system 150 and a base 202 disposed on a base support 102 for processing. As described above, the laser imaging system 150 is operatively coupled to an imaging controller 158, which is further operatively coupled to a system controller 132. The laser imaging system 150 can also be operatively coupled to a positioning controller 204, which can control and adjust the position of the laser imaging system 150. The positioning controller 204 can be relative to... Figure 1 The distributor in the distributor housing 119 is used to adjust the position of the laser imaging system 150.

[0026] In this configuration, the laser imaging system 150 includes a laser source 206 and an imaging unit 208. An optical assembly 210 optically couples the laser source 206 and the imaging unit 208 to a substrate 202 for imaging. The optical assembly may include lenses and mirrors for guiding focused light reflected from the substrate into the imaging unit 208. An optical fiber 212 transfers laser radiation emitted from the laser source 206 to an emission point 214, which may be located at an end of the optical assembly 210 away from the substrate support 102, extend beyond the end of the optical assembly 210 to a position closer to the substrate support 102 than the end of the optical assembly 210, or be recessed within the optical assembly 210. The optical fiber 212 is supported by a support 216 that holds the position of the emission point 214. Laser radiation is emitted from the optical fiber 212 at the emission point 214 and passes through the gap between the emission point 214 and the substrate 202 to provide an illumination field 218. The size of the illumination field 218 can be controlled by controlling the position of the emission point 214 relative to the substrate 202. During processing, the substrate is typically scanned relative to the laser imaging system 150 to illuminate the portion of the substrate to be imaged, as schematically indicated by arrow 220. The laser source 206 is activated when the portion of the substrate to be imaged is partially or entirely within the illumination field 218 during the relative scan, and is deactivated when the portion to be imaged has traversed the illumination field 218 for a sufficient period to acquire the desired image of the entire area to be imaged. This may occur when the first portion of the area to be imaged leaves the illumination field 218, or when the last portion of the area to be imaged leaves the illumination field 218.

[0027] Figure 3 This is an algorithm diagram of an image acquisition control algorithm 300 according to one embodiment. The image acquisition control algorithm 300 is used with a deposition apparatus such as device 100. The image acquisition control algorithm 300 creates triggers for initiating image acquisition of features on substrate 301 via an image acquisition unit, and for initiating illumination of an illumination unit. The illumination unit may be a laser, but in any case, it is capable of generating short radiation pulses within the illumination field. The pulse duration is approximately 1 μsec or less, enabling the acquisition of images of small features on the substrate at relative motion speeds up to 1 m / sec.

[0028] Algorithm 300 uses position markers and position signals from the base fixture to determine when the image acquisition unit begins acquiring images and when the laser source begins irradiation. Typically, this algorithm employs a defined coordinate system, which the controller uses to execute Algorithm 300. The base has a defined origin 302, located relative to the also known original position 304 of the fixture (x, y, y). H ,y H The known position (x) of ) S ,y S Features on the substrate (x) F,y F The design position 306 of the fixture is known relative to the origin 302 of the substrate. In an embodiment where the substrate moves along the y-direction during processing, the y-position of the fixture, the origin of the substrate, and the feature are respectively y h y s and y f They are offset by the same distance 308 from their original positions in the y-direction. If the laser imaging system moves during processing, the position of the illumination field 310 is always y. i The design dimension of the feature is Δx. F and Δy F The illumination field 310 generated by the laser imaging system has a known position (x) relative to the original position of the fixture. I ,y I The illumination field also has a size Δx. I and Δy I Therefore, in the y-direction, the illumination field from Extend to Or if the laser imaging system moves, the illumination field will shift from... Extend to At any time during the process, the y-position of the fixation is... h All of this can be determined from the actuator location.

[0029] Various position markers are provided to the controller, such as controller 132. The algorithm determines when to activate the image acquisition unit and the laser source to acquire an image of the feature based on the expected location of the feature. The size of the illumination field is set to provide sufficient coverage such that any offset between the expected location and the actual location of the feature is less than the amount required to keep the entire feature within the illumination field during exposure.

[0030] Let the relative velocity between the substrate and the laser imaging system in the y-direction be v, and the pulse duration be t. The algorithm calculates the illumination event to illuminate feature 306. The illumination event can be calculated when the entire feature 306 is within the illumination field 310. This is in the y-direction. This occurs when the fixation position is offset by y relative to the base origin in the y direction. HS Then, when lit, the position of the retainer is The lighting event can be calculated based on the fixture location, time, or any other parameters that can be determined from the parameters of the deposition operation. If the lighting event is displayed as a time, it will be... The time.

[0031] The duration of the light illumination is minimized to avoid image distortion. The substrate and laser imaging system can move relative to each other during image acquisition. Illuminating the scene for a duration longer than the time required to acquire the desired image may result in reduced image sharpness. The algorithm calculates the light-off event after the illumination event, once the features have traversed the illumination field. This is in the y-direction. This occurs at certain times. Algorithm 300 can calculate the position of the light-off retainer as... Or calculated as The duration of the pulse is chosen as the time it takes for the feature to travel through the illumination field, i.e.

[0032] The laser imaging system is positioned in a way that makes the x-position of the illumination field the same as the x-position of the feature design.

[0033] Figure 4 This is a flowchart outlining a method 400 for acquiring images of positional features on a substrate. In 402, the substrate is situated on a substrate support of a processing apparatus. Typically, the processing apparatus is used to perform processes, such as adding or removing material from the substrate, and the positioning features of the substrate are used to guide the process. Positional features can be special features, such as markings or structures, specifically added to the substrate for positioning, or they can be features added to the substrate for some other purpose and used here for positioning the substrate.

[0034] At position 404, the substrate is positioned for imaging by the laser imaging system. The substrate can be moved into place relative to the laser imaging system by using a substrate holder. In some cases, the substrate support includes a frictionless surface, allowing the substrate holder to move the substrate with almost no resistance. In some cases, the laser imaging system can also be moved. For example, an air bearing coupled to a guide rail can be used to configure the laser imaging system on the positioning system. The laser imaging system includes a laser source oriented to direct laser radiation towards the imaging area. The imaging unit is positioned close to the laser source to image the laser radiation reflected from the substrate.

[0035] The substrate is positioned for imaging at a location determined by the expected location of a positioning feature. The expected location of the positioning feature is a predetermined position on the substrate where the feature is expected to be found. The laser imaging system and the substrate are positioned relative to each other such that the expected location is close to the illumination field of the laser source.

[0036] At position 406, the substrate is scanned relative to the laser imaging system. The desired location of the positioning feature is moved toward the edge of the illumination field of the laser source. When the desired location is a predetermined distance from the edge of the illumination field, the imaging unit is activated to begin acquiring image data. At this time, the laser source is not activated. Typically, the processing device has a housing that isolates the substrate support and the laser imaging system, so any light source other than the laser source is minimized.

[0037] At point 408, the laser source is activated when the imaging unit can acquire an image of the positioning feature. The laser source can be activated when a portion of the positioning feature is expected to enter the illumination area, or when a small portion of the positioning feature within the illumination field of the laser source is expected to be at its maximum, or when the entire positioning feature is initially expected to be within the illumination field of the laser source. In one case, the laser source is activated when the leading edge of the positioning feature is expected to reach the edge of the illumination field. The expected position of the positioning feature can be at its end or at its center. If the expected position of the positioning feature is at its end, the laser source can be activated when the expected position of the positioning feature is expected to reach the edge of the illumination field. If the expected position of the positioning feature is at its center, the expected position of the end of the positioning feature can be determined using the known size of the positioning feature, and the laser source is activated when the end of the positioning feature is expected to reach the edge of the illumination area.

[0038] In other cases, the laser source can be activated when the positioning feature, or most of the positioning feature, is expected to be entirely within the illumination field of the laser source. In this case, the laser source is activated when the trailing edge of the positioning feature is expected to reach the edge of the illumination area, determined by the known geometry and expected position of the positioning feature. Activating the laser source only when the majority or all of the positioning feature is within the illumination field minimizes the exposure time for image acquisition, thereby minimizing substrate movement during image acquisition. Minimizing substrate movement during image acquisition produces the sharpest possible image.

[0039] At 410°, the substrate and the laser imaging system scan each other, causing the positioning feature, or a portion thereof, to pass through the illumination field of the laser source within the transmission time. The transmission time can be defined in several ways. In one case, the transmission time is the time between the first end of the positioning feature entering the illumination field of the laser source and the last end of the positioning feature leaving the illumination field. In another case, the transmission time is the time between the last end of the positioning feature entering the illumination field (after which no other end of the positioning feature enters the illumination field) and the first end of the positioning feature leaving the illumination field. In either case, all or only a portion of the positioning feature can pass through the illumination field. The transmission may occur in as little as 1 μsec. The transmission time can be determined using the known size of the illumination field and the transmission velocity.

[0040] At position 412, the laser source is turned off. The activation time of the laser source is defined as the time between activating and deactivating the laser source. The activation time of the laser source can be the same as or different from the transmission time. The activation time of the laser source can coincide with or be simultaneous with the transmission time, overlap with the transmission time, or include the transmission time. In one case, the activation time and the transmission time coincide and overlap. In another case, the activation time and the transmission time are contiguous and overlap. In yet another case, the activation time and the transmission time occur simultaneously, and the activation time can overlap with or include the transmission time. In any case, both the activation time and the transmission time are related to the desired portion of the positioning feature illuminated during the transmission time.

[0041] In cases where an image of the entire localization feature is required but cannot be acquired in a single exposure, the substrate and laser imaging system can be repositioned for a second exposure due to factors such as the size of the illumination field of the laser source or the size of the imaging field of the imaging unit, to acquire other parts of the localization feature in a manner similar to method 400.

[0042] At position 414, the imaging unit is turned off. Imaging time can be defined as the time between activating and deactivating the imaging unit. The imaging time is longer than the activation time of the laser source because obtaining a short laser pulse is more direct than obtaining useful exposure within a short exposure time. In the embodiments described herein, the positioning features can be on the order of approximately 1 μm, and the substrate scanning speed can be up to 1 m / sec. Therefore, in some cases, images can be acquired within a duration of 1 μsec using the methods and apparatus described herein. Such short exposures are easier to achieve using a short laser activation time of 1 μsec than using a longer imaging time of 1 msec or longer.

[0043] Method 400 can be repeated to image multiple positioning features. In each case, the expected location of the positioning feature is known, and the substrate and laser imaging system are positioned such that the expected location is placed near the illumination field of the laser source. It should be noted that due to placement errors of the substrate, placement errors of the laser imaging system, errors in applying the positioning feature to the substrate, and thermal displacement and deformation, images taken based on the expected location of the positioning feature may not capture the desired image. In this case, the acquired images can be analyzed to determine the magnitude and direction of the position correction that can be taken. Method 400 can then be repeated, applying the position correction before or during the execution of method 400. Typically, the expected location of the positioning feature is modified by position correction before repeating method 400, but in addition to modifying the expected location of the positioning feature, or instead of modifying the expected location of the positioning feature, a deviation may also be applied to the position of the substrate and / or the laser imaging system.

[0044] Figure 5This is a flowchart summarizing method 500, which can be used with the apparatus described herein and other methods. Method 500 is a method for determining the location and orientation of positioning features of a substrate based on a laser-irradiated image. At 502, an image of the substrate region is obtained at the location where the positioning features are expected to be found, the image being obtained using the laser imaging system described herein.

[0045] At position 504, a set of grid points is defined within the image. These grid points are defined by their x and y coordinates in a common coordinate system of points within the image; that is, the image is captured by positioning the imaging system at these coordinate-defined points. The geometry of the imaging system determines the boundary coordinates of the image in the coordinate system. The grid points are demarcated between these coordinates of the image boundary. Any number of grid points can be used; a larger number of grid points is helpful when locating features with complex shapes.

[0046] The intended shape and size of a location feature are typically defined by coordinates in the same coordinate system. For example, the vertices of a polygonal location feature can be defined by an ordered set of coordinate pairs, where adjacent coordinate pairs define the positions of vertices connected by edges. For non-polygonal shapes with curved profiles, coordinates can define adjacent points on the edge contours of the shape. More points in the shape definition of such shapes improve shape definition by minimizing the error of the assumed straight edges between adjacent points.

[0047] At point 506, for each grid point defined in 504, multiple lines are defined through that grid point. These lines can be defined as a set of coordinate pairs representing individual pixels in the image along those lines, or they can be defined as a set of endpoints. The number of lines is predetermined based on the complexity of the shape being imaged, and the number of lines can be increased if the localization features defined in the image by the first execution of method 500 are unsatisfactory. These lines are typically chosen to uniformly cover the plane, for example, radiating from the origin at equal angles.

[0048] At position 508, for each line defined at position 506, determine the brightness variation along that line from pixel to pixel in the image. For each pixel P along that line... 1 The pixel is defined by a set of coordinate pairs that define the line. Defining the brightness of pixels It is certain. There is at least one adjacent pixel P on this line. 2 In coordinates Brightness at the location It is also certain. Subtracting the two brightness values, that is... Determine pixel P 1 The brightness change at a given point. This is usually expressed as an absolute value. This type of brightness change is a "positive" brightness change. Alternatively, a "reverse" brightness change can be used, where P... 1With the preceding pixel P 0 In contrast, or by using an "intermediate" brightness variation, that is, from P... 0 To P 1 To P 2 The average brightness change.

[0049] Brightness variations are generally used to indicate the location of boundaries in an image. Among 510 types, a predetermined number of pixels with the highest brightness variation, along with points on lines having the highest brightness variation amplitude, are recorded as candidate pixels or points representing shape boundaries within the image. For all grid points defined in the image, the operations 506 (defining the line), 508 (analyzing the brightness variation along the line), and 510 (recording the maximum brightness variation amplitude) are repeated to obtain a set of points representing candidate points for defining the edges of shapes captured in the image.

[0050] At point 512, the recorded points are analyzed to determine which points lie on the image boundaries defined as features. Any number of shape recognition algorithms can be used to determine which points can be used to define the boundaries of shapes in the image. The known shape of the localized features influences the choice of algorithm. For example, if the shape is known to be circular or approximately circular, equidistant distances to points can be used as a search criterion. For more complex shapes, distance-based distinctive features can be computed in the matching algorithm. For example, a test shape defined by the known shape and size of the localized features can be defined by coordinates, and the distances between the recorded points and the test shape can be determined. The test shape can then be searched within the defined range of known shape and size, significantly reducing distance statistics. The results of this search can be improved by excluding statistical outliers to obtain a "best" score for each test shape, and the test shape with the best total score can be identified as the most likely representative shape in the image.

[0051] Based on this optimal test shape, the shape can be further refined. For example, if the boundary of the test shape is defined by the coordinate pairs of pixels on the boundary, a curvature metric can be applied pixel by pixel to improve the test shape to fit the recorded points. At 514, based on the analysis at 512, a set of coordinates is defined to represent the boundaries of the localized features in the image.

[0052] After defining the boundaries of localized features in an image using coordinates, the characteristics of those features can be determined. At coordinate 516, the centroid of the coordinates defining the boundaries of the localized feature can be calculated as the "center" of the feature. This location can be recorded in the system as the actual position of the localized feature on the basis. Alternatively, the maximum or minimum x-value and the maximum or minimum y-value can be used as the position of the localized feature. When the position is defined at 516, the positional error of the localized feature can be determined at 518. The positional error is the difference between the coordinates of the localized feature defined by image analysis and the expected coordinates of the localized feature. This positional error can be used to adjust the basis processing scheme.

[0053] At 520, the rotation error of the localization feature can be defined. A rotation transformation can be applied to the coordinate set that defines the boundary of the localization feature in the image. For example, the rotation angle can be defined in radians, and the xy offset of each pixel in the coordinate set defining the boundary of the localization feature in the image can be defined based on the radial coordinate of each pixel. After applying the rotation transformation, the difference between the rotated coordinate set of the image boundary and the expected coordinate set of the localization feature boundary can be calculated. The degree of rotation that minimizes this difference can be used as the rotation error of the image. The rotation error can be calculated before or after adjustments for any positional errors identified at 518.

[0054] At position 522, the deformation error of the positioning feature can be defined. The deformation error describes the distortion of the positioning feature relative to its expected shape. If the deformation error is not detected and compensated for, it introduces processing errors based on the assumption that the positioning feature's shape is correct. For example, if a corner of a square positioning feature is misaligned, making the feature less square, the feature might be found and positioned, but the processing system might incorrectly record its position based on the odd shape. The deformation error is typically determined after compensating for any positional and rotational errors. The pixel-wise errors of the position-compensated and rotation-compensated images can be calculated and denoted as the deformation error. To process the substrate, the recorded position of the positioning feature can be adjusted based on the identified deformation error.

[0055] Method 500 can be used to locate and define multiple positioning features of a substrate. Errors detected in the multiple positioning features can be analyzed to identify placement and orientation system errors of the substrate in the processing system. For example, similar rotational or positional errors among multiple positioning features can represent an overall rotational or positional error in the substrate placement. Different rotational or positional errors can represent deformation of the substrate or misalignment of positioning features on the substrate. Method 500 and its variations are executed using a digital processing system programmed with instructions suitable for representing the various coordinates and operations mentioned in Method 500. The digital processing system receives data representing an image from an imaging unit and automatically identifies the boundaries of features in the image, and optionally, the positional, rotational, and deformation errors of the positioning features in the image. The results of Method 500 can be used for applications such as... Figure 1 The deposition equipment 100 is used to control the precise deposition of materials on the substrate.

[0056] Figure 6 This is an isometric top view of a deposition apparatus according to another embodiment. Figure 6 The device in the middle is similar to Figure 1 The device in it is different in that Figure 6The apparatus does not include the laser imaging system 150. The first laser imaging system 650 is movably coupled to an imaging rail 604, which is part of the deposition assembly support 616. Figure 1 The deposition assembly support 616, like the one in the model, includes a beam or rail 117, in this case a deposition rail. The deposition assembly support 616 includes an extension 620 that supports the first imaging system 650 and the second imaging system 652. The extension 620 includes a first post 622 extending from a first end 624 of the deposition rail 117 and a second post 626 extending from a second end 628 of the deposition rail 117. The extension 620 also includes an imaging rail 604 extending from the first post 622 to the second post 626, substantially parallel to the deposition rail 117.

[0057] Each of the first imaging system 650 and the second imaging system 652 is substantially identical to imaging system 150. The first imaging system 650 is coupled to imaging rail 604 via a first imaging carriage 654. The second imaging system 652 is coupled to imaging rail 604 via a second imaging carriage 656. A distributor housing 119 is located between the first imaging system 650 and the second imaging system 652. Each of the first imaging carriage 654 and the second imaging carriage 656 has a lateral extension that supports the first and second imaging systems 650 and 652 at a certain gap from imaging rail 604. This gap allows each of the first and second imaging systems 650 and 652 to move substantially along the entire length of imaging rail 604 without interference from the deposition housing 119.

[0058] The device 600 has four independently movable imaging systems. The first two imaging systems, 650 and 652, are located on the first side of the deposition support assembly 616. The device 600 has a third imaging system 660 and a fourth imaging system 662, each of which is a laser imaging system, similar to imaging systems 650 and 652. Here, imaging rail 604 is the first imaging rail, while the second imaging rail 664 is part of the deposition support assembly 616. In this case, both the first and second imaging rails 604 and 664 are mounted on two columns 622 and 626, and extend parallel to each other between the two columns 622 and 626. Imaging systems 660 and 662 are each supported on the second imaging rail 664 by an imaging carriage. Specifically, a third imaging carriage 674 is coupled to the second imaging rail 664 to support the third imaging system 660, and a fourth imaging carriage 676 is coupled to the second imaging rail 664 to support the fourth imaging system 662. The spacing between imaging rails 604 and 664 allows the first and second carriages 654 and 656 to move along the first imaging rail 604 without interference from the third and fourth carriages 674 and 676. In this way, all four imaging systems can be positioned substantially along the entire length of the deposition support assembly 616. Using multiple imaging systems allows for the acquisition of a large number of images in a shorter time, thereby accelerating processing dependent on this imaging.

[0059] Any number of the laser imaging systems described herein can be used in this device. Figure 6 The diagram illustrates four imaging systems, but any number of such systems can be used. For example, two imaging systems can be used on one of two imaging rails, or one imaging system can be used on each imaging rail. Imaging systems can be added to one or two imaging rails simply by placing the carriage of the imaging system on the desired imaging rail. In some cases, because the carriage is coupled to the imaging rail via an air bearing, the air bearing of the added imaging system can be activated, allowing the added imaging system to move along the selected imaging rail. Configuring multiple laser imaging systems allows the device to simultaneously image multiple locations using the imaging accuracy of laser radiation, thereby improving the imaging speed of various parts of the substrate. Using multiple imaging devices can also improve the imaging accuracy of a single location on the substrate if it is necessary to acquire and compare two or more images of a location.

[0060] Although embodiments of the invention have been described above, other further embodiments of the present disclosure may be conceived without departing from its basic scope, the scope of which is defined by the appended claims.

Claims

1. A deposition apparatus comprising: Base support components; and A deposition assembly, the deposition assembly including an optically coupled laser imaging system disposed on the substrate support.

2. The deposition apparatus of claim 1, wherein the deposition assembly includes a guide rail attached to a support located on an opposite side of the substrate support, and a dispenser assembly movably coupled to the guide rail.

3. The deposition apparatus of claim 2, wherein the dispenser assembly houses the laser imaging system.

4. The deposition apparatus of claim 1, wherein the laser imaging system comprises a laser source having an emission wavelength of approximately 600 nm.

5. The deposition apparatus of claim 4, wherein the laser imaging system further comprises an imaging unit having a sensitivity distribution matching the emission wavelength of the laser source.

6. The deposition apparatus of claim 5, wherein the laser source has a pulse duration of 1 μsec or less.

7. The deposition apparatus of claim 6 further includes a controller configured to scan a substrate positioned on the substrate support relative to the laser imaging system, activate the imaging unit for an imaging time, and activate the laser source for an activation time, wherein the activation time is included in the imaging time.

8. The deposition apparatus according to claim 7, wherein the laser source is a laser diode.

9. The deposition apparatus of claim 1, wherein the laser imaging system is one of a plurality of laser imaging systems coupled to the deposition assembly.

10. A method for imaging features on a substrate, comprising: The laser imaging system includes a laser source and an imaging unit, relative to the laser imaging system scanning the substrate; The imaging unit is activated before the end of the feature reaches the illumination field of the laser source; When a portion of the feature reaches the illumination field, the laser source is activated; After the activation time, the laser source is turned off; and After the imaging time, the imaging source is turned off, wherein the imaging time includes the activation time.

11. The method of claim 10, wherein the activation time is less than 5 μsec.

12. The method of claim 11, wherein the imaging unit is a camera having a sensitivity matching the emission wavelength of the laser source.

13. The method of claim 12, further comprising positioning the substrate and the laser imaging system relative to each other based on the expected location of the features.

14. The method of claim 13 further includes automatically identifying the boundaries of features in the image.

15. The method of claim 14, further comprising automatically identifying the positional error of the feature.

16. The method of claim 14, further comprising automatically identifying rotational errors of the features.

17. The method of claim 10, wherein the laser imaging system is a first laser imaging system, and the method further comprises: A first image of the feature is acquired using the first laser imaging system; as well as A second image of the feature is acquired using a second laser imaging system.

18. The method of claim 17, wherein the first laser imaging system and the second laser imaging system are coupled to a support extending across a substrate support, the substrate being disposed on the substrate support for imaging.

19. A deposition apparatus, comprising: Base support components; and Deposition assembly, the deposition assembly including a laser imaging system disposed on the substrate support, the laser imaging system comprising: A laser source fiber coupled to an optical assembly to direct laser radiation from the laser source to the substrate support; and An imaging unit is configured to collect laser radiation reflected by the optical components.

20. The deposition apparatus of claim 19, further comprising a position controller for positioning the laser imaging system.

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