Apparatus for positioning substrate for deposition machine and method thereof

Abstract

To provide a method for accurately measuring a position of a substrate in ink jet printing.SOLUTION: A deposition assembly of a deposition apparatus comprises: a rail 117 extending between supports 120 located on both sides of a substrate support portion 102, a dispenser assembly 104 movably connected to the rail, and an imaging system 150 connected to the rail and comprising an LED light source. The deposition method also is a method for imaging a shape on the substrate, and the method includes: scanning the substrate relative to an imaging system including an LED light source 152 and an imaging unit 154; activating the imaging unit before an extreme edge of the shape reaches an illumination area of the LED light source; activating the LED light source when a portion of the shape reaches the illumination area; and deactivating the LED light source after an activation period of time, and deactivating the imaging unit after the imaging period of time, where the imaging time encompasses the activation time.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims priority based on U.S. Provisional Application No. 63 / 198,555, having a filing date of October 27, 2021, and incorporates the same herein by reference in its entirety.

[0002] Embodiments of the present invention generally relate to deposition apparatuses. In particular, a deposition apparatus having a movably attached work platform is described.

Background Art

[0003] Inkjet - based deposition for lamination is common in office and home printers, as well as in industrial printers used for display manufacturing, deposition of large - scale writing materials, adding materials to manufactured articles such as printed circuit boards, and construction of biological articles such as living tissues. In most commercial and industrial inkjet - based deposition machines and some consumer printers, a dispenser for adding material to a substrate is used. This dispenser ejects a controlled amount of deposition material towards the substrate at a controlled time and speed so that the deposition material reaches the target location on the substrate and forms a mark having a desired size and shape.

[0004] In some cases, such as in the display manufacturing industry, extremely precise deposition is achieved by depositing a very small amount of material at a very precise location. The diameter of the deposited area is, in some cases, deposited in the range of about 10 μm to about 15 μm. In order to place the material so precisely on the substrate, the substrate must be precisely positioned and / or the position of the substrate must be precisely known. An image - processing system using a camera is commonly used to photograph the substrate and accurately measure its position, but acquiring and processing multiple images is time - consuming. A better method for accurately measuring the position of the substrate for inkjet printing is needed.

Summary of the Invention

[0005] According to the embodiments described in this specification, there is provided a deposition apparatus including a substrate support portion and a deposition assembly provided with an imaging system disposed between one side and the other side of the substrate support portion, the imaging system including an LED light source.

[0006] According to another embodiment described in this specification, there is provided a method for imaging a pattern on a substrate. The method includes scanning the substrate with an imaging system including an LED light source and an imaging unit, activating the imaging unit before the outermost end of the pattern reaches the irradiation region of the LED light source, activating the LED light source when a part of the pattern reaches the irradiation region, stopping the LED light source after an operation time, stopping the imaging unit after an imaging time, and the imaging time including the operation time.

[0007] According to another embodiment described in this specification, there is provided a deposition apparatus including a substrate support portion and a deposition assembly provided with an imaging system disposed between one side and the other side of the substrate support portion. The imaging system includes an LED light fiber coupled to an optical assembly that guides light rays from an LED light source toward the substrate support portion, and an imaging unit disposed to capture the light rays reflected through the optical assembly.

Brief Description of the Drawings

[0008] To understand the features of the present disclosure described above in detail, a more detailed description of the present disclosure briefly summarized above is provided by referring to the embodiments. Some of those embodiments are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings merely illustrate exemplary embodiments and thus do not limit the scope, and may also be applied to other equally effective embodiments.

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[0015] For ease of understanding, the same reference numerals are used for the same components common to multiple figures where possible.

[0016] The elements and features of one embodiment are understood to be beneficially incorporated into other embodiments without further description.

Mode for Carrying Out the Invention

[0017] In this specification, a deposition apparatus having a work platform is described that can be fed above the work surface of the deposition apparatus so that a substrate can be loaded and unloaded, and can be stored adjacent to an end of the work surface at a height at least partially below the reference height of the work surface. FIG. 1 is a perspective view from above of a deposition apparatus 100 according to an embodiment. The deposition apparatus has a substrate support 102, a deposition assembly 104, and a holder assembly 106 for manipulating the substrate for deposition. The deposition apparatus 100 includes a base 108, typically a massive body, to minimize the transmission of vibrations to the operating parts of the deposition apparatus 100. In one example, the base 108 is a block of granite. The deposition assembly 104 includes a deposition assembly support 116, and the deposition assembly support 116 includes stands 120 disposed on each side of the base 108 and a rail or beam 117 extending between the stands 120 from one side of the substrate support 102 to the other.

[0018] The substrate support part 102 has a first section 102A, a second section 102B, and a third section 102C between the first section 102A and the second section 102B. The first section 102A and the second section 102B are intermediate preparation areas (staging areas) for substrates entering and exiting the deposition apparatus 100, and the third section 102C is a working area for positioning the substrate to be processed with respect to the deposition assembly support part 116. The substrate support part 102 has a working surface 110 and means for substantially eliminating friction on the working surface 110. Here, the working surface 110 is, for example, a gas cushion table that provides a gas cushion for floating the substrate, such as air, low-oxygen air, dry air, nitrogen, or other suitable gases. The working surface 110 is provided with a plurality of holes (not shown in the drawings) capable of emitting a gas jet, thereby providing an upward pushing force for holding the substrate at a desired height above the working surface 110. Further, the height of the substrate may be precisely locally controlled by enabling the controlled recovery of gas from the gas cushion that is floating the substrate from some of the holes. In one embodiment, the third section 102C has a gas supply hole and a gas recovery hole. The gas supply hole and the gas recovery hole individually control the gas in the gas cushion, and thus control the height at which the substrate floats on the substrate working surface 110.

[0019] The deposition assembly 104 includes a dispenser assembly 114 coupled to a beam 117. The dispenser assembly 114 includes a dispenser housing 119 coupled to a deposition carriage 122, and the deposition carriage 122 moves along the beam 117 to position the dispenser assembly 114 with respect to the substrate disposed in the third section 102C of the substrate support part 102. The dispenser housing 119 houses one or more dispensers (not shown), and these dispensers discharge deposition material onto the substrate positioned on the substrate support part 102 under the deposition assembly 104.

[0020] In actual operation, the substrate is positioned below the deposition assembly 104 by the holder assembly 106. The holder assembly 106 firmly holds the loaded substrate and moves the substrate along the substrate support 102 to position the substrate relative to the deposition assembly 104 so that the printing material is accurately dispensed onto the substrate. The holder assembly 106 in this case generally extends in a first direction along the substrate support 102 and translates the substrate in the first direction while deposition is taking place. This first direction is indicated by arrow 124 in FIG. 1. Generally, the dispenser assembly 114 moves in a second direction substantially perpendicular to the first direction along a beam 117 that extends substantially in the second direction indicated by arrow 126 in FIG. 1. This second direction 126 may be referred to as the "x-direction", and the beam 117 may be referred to as the "x-beam".

[0021] The control unit 132 is operatively coupled to the holder assembly 106 and the deposition assembly 104 and controls the movement of the substrate positioned on the substrate support and the deposition onto the substrate. The control unit 132 may directly control the actuators of the holder assembly 106 and the deposition assembly 104. Alternatively, the control unit 132 may be operatively coupled to a holder assembly control unit coupled to the holder assembly 106 and a deposition assembly control unit coupled to the deposition assembly 104. The control unit 132 controls the movement and positioning of the substrate on the substrate support 102. Further, the control unit 132 controls the movement of the dispenser assembly 114 on the beam 117 and the ejection of the deposition material from the dispenser assembly 114 onto the substrate.

[0022] Imaging system 150 is coupled to dispenser assembly 114. Imaging system 150 includes an LED light source 152 and an imaging unit 154. LED light source 152 emits light rays toward a substrate positioned on substrate support 102 located under dispenser assembly 114. Imaging unit 154 detects the illumination light rays reflected from the substrate. Imaging unit 154 can include a digital camera or other high-precision image acquisition components. Further, imaging unit 154 includes optical components for focusing light rays into the image acquisition components. LED light source 152 and imaging unit 154 are arranged such that LED light source 152 forms an irradiation area on the substrate within the imaging area of imaging unit 154.

[0023] LED light source 152 may emit light rays selected to minimize the impact on other aspects of deposition apparatus 100 and the processes performed by deposition apparatus 100. For example, in many cases, a curable material is deposited on a substrate using deposition apparatus 100. Such materials can typically be cured using short-wavelength electromagnetic radiation such as ultraviolet light. These materials often also react to short-wavelength visible light and may be less reactive to longer-wavelength visible light. In industries such as the display manufacturing industry, uniform processing may be important to achieve high-precision results, so an LED light source that emits long-wavelength light can be selected to minimize any impact on the deposited material. In this regard, a light source having an emission wavelength of 650 nm or greater is useful. In one example, the light source has an emission wavelength of 650 nm. In other examples, the light source has an emission wavelength of 800 nm.

[0024] The LED light source may be an array of a plurality of LEDs arranged to provide a desired illumination area so that the imaging system can acquire an image in a very short time. By imaging in a very short time, it becomes possible to acquire a clear image of any range of the moving substrate. Further, the combination of the light source and the image acquisition component can be selected so as to maximize the sensitivity of the image acquisition component to the light rays emitted by the LED light source. For example, the Dalsa Nano M2020 camera has a sensitivity close to the peak at a wavelength of 650 nm. Silicon-based NIR image acquisition units typically have a peak sensitivity around 800 nm. A plurality of LED light sources having a radiation spectrum that peaks at these wavelengths or wavelengths in the vicinity thereof can be used.

[0025] The LED light source 152 can be fiber-coupled to transfer the LED emitted light to a radiation surface that can be placed close to the substrate. By using a plurality of LED light sources, high brightness and a high-speed transition of the peak brightness that does not require reduction of laser light correlation are provided. For many display applications, the substrate has a positioning feature such as a fiducial mark that can be used to accurately calibrate the position of the substrate. This mark may be of a small size, for example, from 0.5 mm to 5 mm. This mark may be cross-shaped. By fiber coupling, the light emitting surface can be positioned so as to form a uniformly bright spot that encompasses all or an essential part of the field of view necessary for the light rays to confirm the position of the mark.

[0026] The imaging system 150 is configured to acquire an image while the substrate and the dispenser assembly 114 move relative to each other. This relative movement can be at a high speed, such as 1 m / s in some cases. The imaging control unit 158 is operatively coupled to the LED light source 152 and the imaging unit 154 to drive image acquisition during the relative movement. Here, the LED light source has a short pulse emission ability of at least several μsec. That is, at a pulse duration of several μsec, defined as the duration from the start to the end of the pulse, or in some cases shorter than 1 μsec, the average luminance of the area of the emitted light beam increases to reach half of the maximum value at the start of the pulse and decreases to reach half of the maximum value at the end of the pulse. The imaging control unit 158 is realized by a printed circuit board including a digital circuit. This digital circuit transmits commands for starting and stopping image acquisition to the imaging unit 154, and transmits commands to turn on and off a switch, or alternatively, commands to oscillate a pulse having a predetermined duration, to a switch electrically coupled between a power source or the power source and the LED light source 152. The imaging control unit 158 is operatively coupled to the control unit 132 to transmit and receive signals indicating information used to control the imaging of the substrate, and is optionally also operatively coupled to other control units such as a holder assembly control unit and a dispenser assembly control unit. The imaging control unit 158 is configured to transmit a signal indicating the image acquired by the imaging unit 154 to the control unit 132 for analysis. Further, the imaging control unit 158 is configured to control the imaging unit 154 and the LED light source 152 to acquire an image when a form of the substrate, such as a positioning form, is expected to be within the field of view of the imaging unit 154, based on information received from the control unit 132, such as the predicted position of the form and the moving speed of the substrate.

[0027] The LED light source is electrically coupled to a power supply configured to supply a voltage to the LED light source that achieves a desired luminance for imaging during the above-described duration. A plurality of LED emitters in the LED light source may be selected to have a total lumen such that a clear image can be obtained during the short duration as described above. In one example, the LED array may be an array of 24 LEDs that emit light at 610 nm to 650 nm, where each LED has a luminous output of about 65 lumens at an applied voltage of about 1.8V. LEDs that can be used are, for example, LUXEON (registered trademark) Star LXZ1-PH01 LEDs manufactured by Lumileds located in San Jose, California. In one example, 40 such LEDs are assembled into a 5x8 array. In a further example, 24 such LEDs are assembled into a 4x6 array. In other examples, 40 LEDs can be assembled in a circular shape. In still other examples, more LEDs can be used. For example, in one example, 50 LEDs can be used as a light source.

[0028] FIG. 2 is a perspective view of a position acquisition system 200 according to an embodiment. The position acquisition system 200 includes an imaging system 150 that places a substrate 202 on a substrate support portion 102 for processing. As described above, the imaging system 150 is operatively coupled to an imaging control unit 158, and the imaging control unit 158 is further operatively coupled to a system control unit 132. Also, the imaging system 150 may be operatively coupled to a positioning control unit 204 that can control and adjust the position of the imaging system 150. The positioning control unit 204 can adjust the position of the imaging system 150 with respect to the dispenser in the dispenser housing 119 of FIG. 1.

[0029] In this case, the imaging system 150 includes an LED light source 206 and an imaging unit 208. An optical assembly 210 optically couples the LED light source 206 and the imaging unit 208 to the substrate 202 for imaging. The optical assembly 210 may include one or more lenses, prisms, fibers, and / or mirrors for guiding and / or condensing the light reflected from the substrate 202 into the imaging unit 208. An optical fiber 212 transfers the light beam emitted by the LED light source 206 to a radiation point 214. The radiation point 214 may be at one end of the optical assembly 210 spaced from the substrate support 102, extend beyond the end of the optical assembly 210 to a location closer to the substrate support 102 than the end of the optical assembly 210, or be embedded within the optical assembly 210. The optical fiber 212 is supported by a support 216 that maintains the position of the radiation point 214. At the radiation point 214, a light beam is emitted from the optical fiber 212 and passes through the gap between the radiation point 214 and the substrate 202 to form an irradiation region 218. The size of the irradiation region 218 can be controlled by controlling the location of the radiation point 214 relative to the substrate 202. During processing, the substrate 202 is typically scanned relative to the imaging system 150 as schematically indicated by the arrow 220 to irradiate the substrate portion of the object to be imaged. The LED light source 206 is activated when the substrate portion of the object to be imaged is partially or completely within the irradiation region 218 during the relative scanning, and is stopped for a time sufficient to acquire a desired image of the entire range of the object to be imaged when the portion of the object to be imaged passes through the irradiation region 218. This may be when the first portion of the range of the object to be imaged exits the irradiation region 218, or when the last portion of the range of the object to be imaged exits the irradiation region 218. The LED light source 206 can be activated by closing a switch electrically coupled between a power source (not shown) and the LED light source 206. This switch can be controlled by a signal transmitted from the control unit 132 (FIG. 1) or a local control unit for the LED light source 206, or a combination thereof.

[0030] Figure 3 is an algorithm diagram of an image acquisition control algorithm 300 according to an embodiment. The image acquisition control algorithm 300 is used in a deposition apparatus such as the apparatus 100. The image acquisition control algorithm 300 generates a trigger for starting image acquisition of a pattern on the substrate 202 by the imaging unit and a trigger for starting illumination by the illumination unit. The illumination unit can generate uniform light rays of short pulses within the irradiation area. The duration of this pulse is about 1 μsec or shorter, thereby enabling acquisition of an image of a small pattern on the substrate at a relative moving speed of up to 1 m / sec. For this LED light source, for example, an array in which a plurality of LED light sources having a radiation wavelength adapted to the spectral sensitivity of the imaging unit and a light emission output sufficient to acquire a clear image with a short exposure time as described above can be used.

[0031] The algorithm 300 uses position markers together with a position signal from the substrate holder to determine when to start image acquisition by the imaging unit and when to start illumination by the illumination light source. Generally, this algorithm uses a predetermined coordinate system used by a control unit that executes the algorithm 300. The substrate has a predetermined origin 302 located at a known position (x H , y H ) with respect to the home position 304 (x S , y S ) of a known holder. The location 306 (x F , y F ) of the pattern on the substrate is grasped with respect to the origin 302 of the substrate. In an embodiment where the substrate is moved in the y direction during processing, the holder, the origin of the substrate, and the y position of the pattern are y h , y s , and y f , respectively. These are shifted by the same distance 308 from their respective home positions in the y direction. When the imaging system is moved during processing, the position of the irradiation area 310 at any point in time is y i . The pattern is Δx F and Δy Fhas the size of the design. The irradiation area 310 generated by the imaging system is at a known location (x I , y I ) with respect to the home position of the holder. Also, the irradiation area has a size of Δx I and Δy I . Thus, in the y - direction, the irradiation area ranges from y I -(1 / 2)Δy I to y I +(1 / 2)Δy I , or when moving the imaging system, it ranges from y i -(1 / 2)Δy I to y i +(1 / 2)Δy I . At any point in the process, the y - position y h of the holder is determined from the position of the actuator.

[0032] Various position markers are supplied to a control unit such as the control unit 132. In this algorithm, based on the predicted location of the object, it is determined when to activate the imaging unit and the illumination light source to acquire an image of the object. The size of the irradiation area is set such that the deviation between the predicted position of the object and the actual position of the object is within a range sufficient for the entire object to remain within the irradiation area during exposure in any case.

[0033] Let the speed of the relative movement in the y - direction between the substrate and the imaging system be v, and the pulse duration be t. The algorithm calculates the light - emitting event for irradiating the object 306. This light - emitting event may be calculated when the entire object 306 is within the irradiation area 310. This occurs when, in the y - direction, y f -(1 / 2)Δy F =y i -(1 / 2)Δy I . If the holder position is displaced by y HS from the substrate origin in the y - direction, then the holder position at the time of light emission is y i -(1 / 2)Δy I -y f +(1 / 2)ΔyF +y S +y HS It is. The emission event can be calculated in relation to the holder position, time, or any other parameter that can be measured from the deposition job parameters. When the emission event is expressed as time, vt = y i -(1 / 2)Δy I -y f +(1 / 2)Δy F is the time point.

[0034] The emission duration is minimized to avoid image distortion. The substrate and the imaging system may move relative to each other during image acquisition. If an attempt is made to acquire a desired image and irradiate the area for longer than necessary, the sharpness of the image may be reduced. By the algorithm, when the object passes through the irradiation area after the emission event, an extinction event is calculated. In the y direction, this occurs when y f +(1 / 2)Δy F =y i +(1 / 2)Δy I is. By algorithm 300, the extinction holder position is y i +(1 / 2)Δy I -y f -(1 / 2)Δy F +y S +y HS or vt = y i +(1 / 2)Δy I -y f -(1 / 2)Δy F at the time point. The duration of the pulse is selected such that the time for the object to move through the irradiation area, i.e., t = (1 / v)(Δy I -Δy F ).

[0035] The imaging system is positioned such that the x-position of the irradiation region is the same as the x-position of the designed form. The imaging system uses a plurality of illumination light sources that can transition from zero to peak luminance and from peak luminance to zero in a time considerably shorter than the pulse duration. Since the plurality of LED light sources can transition at the same speed as the potential of each LED light source can transition from one to the other, the plurality of LED light sources can emit pulses in the short durations described herein. Also, the plurality of LED light sources emit uniform light rays and in most cases do not require further homogenization to clarify the image.

[0036] Figure 4 is a flowchart showing an overview of a method 400 for acquiring an image of a positioning form on a substrate. At 402, the substrate is positioned on the substrate support of the processing apparatus. Typically, the processing apparatus is used to perform processing such as addition or removal of material to the substrate, and the positioning form of the substrate is used as a guide for this processing. The positioning form may be a special form such as a mark or structure provided to the substrate solely for the purpose of positioning the substrate. Alternatively, the positioning form may be a form provided to the substrate that is for some other purpose but is used here for positioning the substrate.

[0037] At 404, the substrate is positioned for imaging by the imaging system. By applying a substrate holder that moves the substrate, the substrate can be moved to a position relative to the imaging system. In some cases, the substrate support has a frictionless surface so that the substrate holder can move the substrate with little resistance. Further, in some cases, the imaging system can also be moved. For example, the imaging system may be deployed on a positioning system using an air bearing coupled to a rail. The imaging system may include an LED light source oriented to direct an illumination light ray in the direction of the imaging range. The imaging unit is positioned in the vicinity of the LED light source to image the light ray reflected from the substrate.

[0038] The substrate is positioned for imaging at a location determined by the expected location of the positioning feature. The expected location of the positioning feature is a predetermined location on the substrate where the positioning feature is expected to be found. The imaging system and the substrate are positioned relative to each other such that this expected location is in the vicinity of the illumination area of the illumination source.

[0039] In 406, the substrate is scanned relative to the imaging system. The expected location of the positioning feature is moved towards the edge of the illumination area of the illumination source. When this expected location reaches a predetermined distance from the edge of the illumination area, the imaging unit is activated to start acquiring image data. At this time, the illumination source is not operating. Typically, the processing device includes a cover that isolates the substrate support and the imaging system to minimize any light source other than the illumination source.

[0040] In 408, when it becomes possible to acquire an image of the positioning feature by the imaging unit, the illumination source is activated. The illumination source may be activated when a part of the positioning feature is expected to enter the illumination area, when the ratio of the positioning feature inside the illumination area of the illumination source is expected to be maximum, or when the entire positioning feature is first expected to be within the illumination area of the illumination source. In one example, the illumination source is activated when the leading edge of the positioning feature is expected to reach the edge of the illumination area. The expected position of the positioning feature may be the outermost end of the positioning feature or the central part of the positioning feature. When the expected position of the positioning feature is its outermost end, the illumination source can be activated when the expected position of the positioning feature is expected to reach the edge of the illumination area. When the expected position of the positioning feature is its central part, the expected position of the outermost end of the positioning feature can be determined using the known size of the positioning feature, and the illumination source can be activated when the expected position of the outermost end of the positioning feature is expected to reach the edge of the illumination area.

[0041] In other examples, the illumination light source can be activated when the positioning feature or most of it is expected to be entirely within the illumination area of the illumination light source. In this case, when the trailing edge of the positioning feature is expected to reach the edge of the illumination area, as determined by the known geometric shape and expected location of the positioning feature, the illumination light source is activated. By waiting to activate the illumination light source until the maximum or all of the positioning feature is within the illumination area of the illumination light source, the exposure time for image acquisition is minimized, and thus the movement of the substrate during image acquisition is minimized. Minimizing the movement of the substrate during image acquisition results in the sharpest images.

[0042] 410, the substrate and the imaging system are scanned relative to each other such that the positioning feature or a portion thereof traverses the illumination area of the illumination light source during the traversal time. This traversal time can be determined in many ways. In one example, this traversal time is the time between when the first extreme end of the positioning feature enters the illumination area of the illumination light source and when the last extreme end of the positioning feature exits the illumination area of the illumination light source. In another example, this traversal time is the time between when the last extreme end of the positioning feature enters the illumination area and there are no other extreme ends of the positioning feature that enter the illumination area thereafter, and when the first extreme end of the positioning feature exits the illumination area. In either case, only all or a portion of the positioning feature may traverse the illumination area. The time during which the traversal occurs can be as short as about 1 μsec. This traversal time can be determined using the known size of the illumination area and the speed of the traversal.

[0043] At 412, stop the illumination light source. The operating time of the illumination light source is defined as the time between when the illumination light source is activated and when the illumination light source is stopped. This operating time of the illumination light source may be equal to the transition time, or may be different. This operating time of the illumination light source may match and be simultaneous with the transition time, or may overlap with the transition time, or may include the transition time. In one example, the operating time matches and overlaps with the transition time. In another example, the operating time is continuous and overlaps with the transition time. In yet another example, the operating time is parallel to the transition time and can overlap with the transition time or include the transition time. In any case, the operating time and the transition time are correlated to irradiate a desired portion of the positioning form during the transition time.

[0044] An image of the entire positioning form is desired. However, for example, if the size of the irradiation area of the illumination light source or the size of the imaging area of the imaging unit makes it impossible to capture an image in a single exposure, the substrate and the imaging system can be repositioned and a second exposure can be performed in a manner similar to method 400 to additionally capture a portion of the positioning form.

[0045] At 414, stop the imaging unit. The imaging time can be defined as the time between when the imaging unit is activated and when the imaging unit is stopped. This imaging time is longer than the operating time of the illumination light source. This is because obtaining a short emission pulse is easier than obtaining a useful exposure with a short exposure time. In the embodiments described in this specification, the positioning form may be on the order of 1 μm in size, and the speed of scanning the substrate may be on the order of 1 m / second. Thus, in some cases, an image is acquired using the methods and apparatus described in this specification in a time of 1 μsec. Such a short-time exposure is more easily achieved by using a short operating time of 1 μsec and a longer imaging time of 1 msec or more.

[0046] This method 400 may be repeated to image a plurality of positioning forms. In each instance, the expected position of the positioning form is known, and the substrate and the imaging system are positioned such that the expected position is disposed near the illumination area of the illumination source. It should be noted that due to the placement error of the substrate, the placement error of the imaging system, the error in applying the positioning form to the substrate, as well as thermal displacement and deformation, the image captured using the expected location of the positioning form may not capture the desired image. In such a case, the acquired image is analyzed to determine the scale and direction of the applicable position correction. Before or during the implementation of method 400, position correction can be applied to repeat method 400. Typically, prior to the iteration of method 400, the expected position of the positioning form is corrected by position correction, but in addition to or instead of correcting the expected position of the positioning form, the positions of the substrate and / or the imaging system can also be biased.

[0047] FIG. 5 is a flowchart showing an overview of method 500 and other methods that can be used with the apparatus described herein. Method 500 is a method for determining the position and orientation of a positioning form of a substrate from a pulse-irradiated image. At 502, an image of any area of the substrate is acquired at a location where the positioning form is expected to be found. The image is acquired using the imaging system described herein.

[0048] At 504, a set of grid points is defined within the image. These grid points are defined by x-y coordinates in a common coordinate system with the points within the image. That is, the image is acquired by placing the imaging system at points defined by coordinates. The coordinates of the boundaries of the image in the coordinate system are determined by the geometric arrangement of the imaging system. Grid points are defined between the coordinates of the boundaries of the image. Any number of grid points can be used, and the more grid points there are, the more effective it is when the positioning form has a more complex shape.

[0049] Furthermore, the expected shape and size of the positioning feature are typically defined by coordinates in the same coordinate system. For example, the vertices of a polygonal positioning feature can be defined by an ordered set of coordinate pairs, where in this case, adjacent coordinate pairs define the location of vertices connected by an edge. For non-polygonal shapes with a curved outer shape, the coordinates may be such that they define adjacent points on the edge of the shape. Using more points for the shape definition of such shapes improves the accuracy of shape definition by minimizing the error of assuming a linear edge between adjacent points.

[0050] In 506, for each grid point defined in 504, a plurality of line segments passing through that grid point are defined. These line segments can be defined as a set of coordinate pairs indicating each pixel of the image on the line segment, or alternatively, these line segments can be defined as a set of end points. The number of line segments is predetermined based on the complexity of the shape being imaged and can be increased if the definition of the positioning feature in the image was insufficient in the initial implementation of method 500. The line segments are generally selected to evenly cover the plane, for example, extending radially at equal angles from the origin.

[0051] In 508, for each line segment defined in 506, the change in brightness from pixel to pixel along that line segment in the image is measured. For each pixel P on the line segment defined by the set of coordinate pairs (x P1 , y P1 ) belonging to the set of coordinate pairs defining the line segment, the brightness of pixel B 1 is checked. The brightness B P1 of at least one adjacent pixel P P2 , y P2 ) on the line segment at the coordinates (x 2 ) is also checked. The two brightnesses are subtracted to measure the change in brightness at pixel P P2 as B P2 - B P1 . Typically, the absolute value is used. This type of brightness change is a "forward" brightness change. Alternatively, instead of P 1 , using the pixel P that precedes 1 ​0 The "rear" brightness change compared to it, and P 0 starting from P 1 from P 2 It is also possible to use the "central" brightness change, which is the average of the brightness changes from P to P.

[0052] The change in brightness is generally used to indicate where there can be a boundary in the image. At 510, pixels with a predetermined number of brightness changes being the highest, that is, points on the line segment having the maximum brightness change, are recorded as candidates for the boundary of the shape within the image. The calculation 506 for defining the line segment, the calculation 508 for analyzing the brightness change along the line segment, and the calculation 510 for recording the maximum brightness change are repeated for all grid points defined for the image. From this process, a set of points indicating candidate points for defining the edge of the shape obtained in the image is obtained.

[0053] At 512, the recorded points are analyzed to determine which points exist on the boundary of the image of the positioning reference object. Several shape recognition algorithms for determining which points can be used to define the location of the boundary edge of the object in the image may be used. The selection of the algorithm can be influenced by the known shape of the positioning reference object. For example, when the shape is known to be circular or approximately circular, the equality of the distance from any point can be used as a search criterion. For more complex shapes, in the matching algorithm, a distance-based signature can be calculated. For example, a plurality of test shapes defined by the known shape and dimensions of the positioning reference object are defined by coordinates, and the distance from the recorded points to the test shape can be measured. Then, within the limits of the known shape and dimensions, the test shape can be obtained, thereby minimizing the distance statistics. The results of such a search can be improved by excluding statistically outlying values to clarify the "best" score for each test shape, and the test shape with the best overall score can be identified as the closest representation to the shape in the image.

[0054] From such a best test shape, the shape can be further refined. For example, if the test shape has a boundary defined by a pair of coordinates of pixels on the boundary, a curvature metric can be applied to each pixel to improve the test shape that fits the recorded points. In 514, based on the analysis in 512, a set of coordinates is defined as indicating the boundary of the positioning form in the image.

[0055] After defining the boundary of the positioning form in the image, the features of the positioning form in the image can be measured. In 516, the centroid of the coordinates defining the boundary of the positioning form can be calculated as the "center" of the form. This location can be recorded in the system as the actual location of the positioning form on the substrate. Alternatively, the maximum or minimum x value and the maximum or minimum y value can be used as the location of the positioning form. After defining this location in 516, in 518, the position error of the positioning form can be determined. The position error is the difference between the coordinates of the positioning form determined from the image analysis and the expected coordinates of the positioning form. This position error can be used to adjust the processing plan regarding the substrate.

[0056] In 520, the rotation error can be clarified for the positioning form. A rotation transformation can be applied to the set of coordinates defining the boundary of the positioning form in the image. For example, the rotation angle can be defined in radians, and the x - y shift of each pixel in the set of coordinates defining the boundary of the positioning form in the image can be determined based on the radial coordinates of each pixel. After applying the rotation transformation, the difference between the set of coordinates of the boundary of the rotated image and the expected set of coordinates of the boundary of the positioning form can be calculated. The degree of rotation that minimizes this difference can be used as the rotation error of the image. This rotation error can be calculated before or after the adjustment regarding any position error identified in 518.

[0057] In 522, for the positioning form, the forming error can be clarified. This forming error proves the deformation from the expected shape of the positioning form. If this forming error is not detected and corrected, the positioning form may be assumed to be properly formed, which may cause a processing error. For example, when one corner of a square positioning form is provided in an inappropriate location and the positioning form is no longer square, it is possible to find and identify the location of this positioning form, but based on this forming mistake, the location may be wrongly recorded in the processing system. This forming error is typically determined after correction for any position error and rotation error. The error for each pixel of the image after position correction and rotation correction can be calculated and recorded as the forming error. The recorded location of the positioning form can be adjusted based on the identified forming error for the purpose of substrate processing.

[0058] Method 500 can be used to identify and define the locations of multiple positioning forms of a substrate. The errors detected in the multiple positioning forms can be analyzed to identify system errors in the placement and orientation of the substrate in the processing system. For example, similar rotation errors or position errors in the multiple positioning forms may indicate an overall rotation error or position error in the placement of the substrate. Different rotation errors or position errors may indicate deformation of the substrate or a placement mistake of the positioning forms on the substrate. This method 500 and its variations are implemented using a digital processing system programmed with instructions appropriate to represent the various coordinates and operations mentioned in method 500. This digital processing system receives data representing an image from an imaging unit, automatically identifies the boundaries of the form in the image, and optionally identifies position errors, rotation errors, and forming errors of the positioning form in the image. Using the results of method 500, precise deposition of material onto a substrate, for example using the deposition apparatus 100 of FIG. 1, can be controlled.

[0059] FIG. 6 is a perspective view from above of a deposition apparatus according to another embodiment. The apparatus of FIG. 6 is similar to the apparatus of FIG. 1, but differs in that there is no imaging system 150. Instead, a first imaging system 650 is movably coupled to an imaging rail 604 that is part of the deposition assembly support. The deposition assembly support is similar to the deposition assembly support 116 of FIG. 1 and includes a beam or rail 117, which is a deposition rail in this example. The deposition assembly support includes an extension portion that supports the first imaging system 650 and the second imaging system 652. The extension portion includes a first upright portion 622 extending from the first end 624 of the beam 117 and a second upright portion 626 extending from the second end 628 of the beam 117 that is opposite the first end 624. The extension portion further includes an imaging rail 604 that extends substantially parallel to the beam 117 from the first upright portion 622 to the second upright portion 626.

[0060] The first imaging system 650 and the second imaging system 652 are each substantially the same as the imaging system 150. The first imaging system 650 is coupled to the imaging rail 604 by a first imaging carriage 654. The second imaging system 652 is coupled to the imaging rail 604 by a second imaging carriage 656. There is a dispenser housing 119 between the first imaging system 650 and the second imaging system 652. The first imaging carriage 654 and the second imaging carriage 656 each have a lateral extension that supports the first imaging system 650 and the second imaging system 652 at a clearance from the imaging rail 604. This clearance allows the first imaging system 650 and the second imaging system 652 to each move along substantially the entire length of the imaging rail 604 without interference from the dispenser housing 119.

[0061] Apparatus 600 has four individually movable imaging systems. The two imaging systems 650 and 652 described above are installed on the first side of the deposition assembly support. Apparatus 600 has a third imaging system 660 and a fourth imaging system 662, each of which is an imaging system similar to imaging systems 650 and 652. Here, imaging rail 604 is the first imaging rail, and second imaging rail 602 is part of the deposition assembly support. In this example, both the first imaging rail 604 and the second imaging rail 602 are provided on two rising portions 622 and 626, and extend parallel to each other between the two rising portions 622 and 626. Imaging systems 660 and 662 are each supported by the second imaging rail 602 by an imaging carriage. In particular, the third imaging carriage is coupled to the second imaging rail 602 to support the third imaging system 660, and the fourth imaging carriage is coupled to the second imaging rail 602 to support the fourth imaging system 662. The space between imaging rail 604 and imaging rail 602 allows the first imaging carriage 654 and the second imaging carriage 656 to move along the first imaging rail 604 without being affected by interference from the third imaging carriage and the fourth imaging carriage. In this way, all four imaging systems can be positioned substantially over the entire length of the deposition assembly support. By using multiple imaging systems, it becomes possible to acquire a large number of images in a shorter time, thus accelerating the speed of processes that depend on such imaging.

[0062] For such a device, any number of the imaging systems described in this specification can be used. In FIG. 6, four imaging systems are illustrated, but any number of such imaging systems can be used. For example, two imaging systems can be used on one of the two imaging rails, or two imaging systems can be used, one on each imaging rail. The imaging system can be added to one or both imaging rails simply by placing the carriage of the imaging system on the desired imaging rail. In some cases, these carriages can be coupled to the imaging rails using air bearings to drive the air bearings of the added imaging systems and move the added imaging systems along the selected imaging rails. By deploying multiple imaging systems using LED light sources, the device can simultaneously image multiple locations using bright, uniform, and high pulse-time LED light rays, thus increasing the imaging speed of various parts of the substrate. Further, by using multiple imaging devices, the imaging accuracy at a single location on the substrate can be increased when acquiring and comparing two or more images at that location.

[0063] The foregoing relates to embodiments of the invention, but other further embodiments of the disclosure may be devised without departing from the basic scope thereof, which is defined by the scope of the claims that follow.

Claims

1. A deposition apparatus, comprising: A substrate support; a deposition assembly disposed over the substrate support; The deposition assembly comprises: a rail extending between supports located on either side of the substrate support; a dispenser assembly movably connected to the rail; an imaging system coupled to the rail, the imaging system including an LED light source and an imaging unit; an optical assembly for optically coupling the LED light source and the imaging unit to a substrate disposed on the substrate support and directing light reflected from the substrate to the imaging unit, the optical assembly including an optical fiber disposed within the optical assembly for transferring light emitted from the LED light source to a light emission point for illuminating a portion of the substrate; A deposition apparatus comprising:

2. The deposition apparatus of claim 1 , wherein the dispenser assembly houses the imaging system.

3. 10. The deposition apparatus of claim 1, wherein the imaging system comprises an array of LEDs having an emission wavelength of at least about 600 nm.

4. The deposition apparatus of claim 3 , wherein the imaging system further comprises an imaging unit having a sensitivity profile adapted to the emission wavelengths of the plurality of LEDs.

5. 5. The deposition apparatus of claim 4, wherein the LED light source has a pulse duration of 1 [mu]sec or less.

6. 6. The deposition apparatus of claim 5, further comprising a controller configured to scan a substrate positioned on the substrate support relative to the imaging system, activate the imaging unit for an imaging time, and activate the LED light source for an activation time, the activation time being subsumed within the imaging time.

7. The deposition apparatus of claim 6 , wherein the LED light source is coupled to a fiber waveguide.

8. 10. The deposition apparatus of claim 1, wherein the imaging system is one of a plurality of imaging systems coupled to the deposition assembly, and each imaging system of the plurality of imaging systems comprises an LED light source.

9. 1. A deposition apparatus, comprising: A substrate support; a deposition assembly comprising an imaging system disposed over the substrate support; The imaging system includes: an LED light source fiber connected to an optical assembly, the LED light source fiber being optically coupled to the optical assembly by an optical fiber disposed within the optical assembly and directing emitted light from the LED light source to the substrate support; an imaging unit coupled to the optical assembly to capture light reflected through the optical assembly.

10. The deposition apparatus of claim 9 , further comprising a positioning control for positioning the imaging system.

Images