Pattern transfer system, dual lane production line, and pattern transfer method

Abstract

Pattern transfer printing (PTP) systems and methods and dual lane production lines are provided to improve the quality, accuracy, and throughput of pattern transfer printing. A PTP system includes a tape handling unit configured to handle a tape and move the tape in a step and repeat pattern from a supply roll to a take-up roll, the tape including a plurality of pattern transfer sheets as segments thereof, the pattern transfer sheets having respective trench patterns, the tape handling unit configured to controllably convey the pattern transfer sheets for paste filling and, in succession, for pattern transfer printing; a paste filling unit configured to fill conductive printing paste into the trenches of the conveyed pattern transfer sheets; a wafer handling unit configured to controllably convey at least one wafer to a location proximate the pattern transfer sheets for pattern transfer printing; and a paste transfer unit configured to transfer the conductive printing paste from the pattern transfer sheets to the conveyed wafer at the location by releasing the conductive printing paste from the trenches of the pattern transfer sheets filled with the conductive printing paste under irradiation of a laser beam.

Description

Technical Field

[0001] This invention relates to the field of pattern transfer printing (pattern transfer) technology, and more specifically, to the field of photovoltaic cell manufacturing. Background Technology

[0002] U.S. Patent Application Publication No. 2017 / 013724, incorporated herein by reference in its entirety, discloses an apparatus for generating a transfer pattern used in a transfer printing process. A pattern is formed on a substrate, which may be a mesh substrate and has one or more grooves. A filler to be transferred, such as a high-viscosity metal paste, is filled into the grooves of the mesh substrate. After the filler has filled the grooves of the substrate, a filling head, which may include a squeegee and a scraper, translates in a synchronized motion within a working area, such that the filling head remains in full contact with the substrate during the translational motion.

[0003] Lossen et al. (2015), Pattern Transfer Printing (PTP) for Metallization of c-Si Solar Cells TM The 5th Symposium on Metallization of Crystalline Silicon Solar Cells (Lossen et al. (2015), Pattern Transfer Printing (PTP) TM )for c-Si solar cell metallization,5 th The entire contents of the Workshop on Metallization for Crystalline Silicon Solar Cells (Energy Procedia 67:156-162) are incorporated herein by reference, and disclose pattern transfer printing (PTP). TM This is a non-contact printing technology for advanced front-side metallization of c-Si PV solar cells, based on laser-induced deposition on polymer substrates.

[0004] There is a need to improve the accuracy, efficiency, and capacity of existing PTP systems. Summary of the Invention

[0005] The following is a brief overview to provide a preliminary understanding of the invention. This summary is not necessarily considered a key element, nor does it limit the scope of the invention, but is merely a preliminary introduction to the following description.

[0006] One aspect of the present invention provides a pattern transfer (PTP) system, comprising: a strip processing unit configured to process a strip comprising a plurality of pattern transfer sheets as segments, the pattern transfer sheets having respective groove patterns, and the strip processing unit configured to controllably convey the pattern transfer sheets for paste filling and sequential pattern transfer; a paste filling unit configured to fill conductive printing paste into the grooves on the conveyed pattern transfer sheets; a wafer processing unit configured to controllably convey at least one wafer to a position adjacent to the pattern transfer sheets for pattern transfer; and a paste transfer unit configured to transfer conductive printing paste from the pattern transfer sheets to the conveyed wafer by releasing the conductive printing paste from the grooves of the pattern transfer sheets filled with the conductive printing paste under laser beam irradiation; wherein the strip processing unit is configured to move the strip from a feed roller to a take-up roller in a step-and-repeat pattern. Optionally, the strip is cleaned and dried during the post-transfer conveying process.

[0007] Another aspect of the invention provides a pattern transfer (PTP) system comprising a wafer handling system wherein each of two parallel x, z platforms includes two chucks for holding the wafer, each chuck ensuring the wafer is movable along the y, θ axes, thereby enabling faster wafer handling and continuous wafer transport during the pattern transfer process. Multiple cameras photograph the transported wafer, enabling more accurate wafer alignment within the transfer system, thus more accurately aligning the printed grid lines onto the wafer pattern.

[0008] The disclosed PTP system is optimized to improve equipment efficiency and throughput during pattern transfer by continuously supplying wafers and / or using a dual-chuck wafer platform. Furthermore, alignment accuracy is improved by using multiple cameras to align the wafer, more accurately aligning the transfer sheet at the transfer location, and positioning the paste filling unit in a near-vertical position, thereby reducing the time between paste filling and pattern transfer.

[0009] The above aspects of the present invention, including additional and / or other aspects and / or advantages, are set forth in the description below; anything that can be inferred from the description below, and / or learned through exemplary embodiments of the present invention, is within the scope of protection of the present invention. Attached Figure Description

[0010] To better understand embodiments of the invention and to illustrate how they can be implemented, reference will now be made purely by way of example to the accompanying drawings, in which corresponding elements or portions are indicated by the same reference numerals.

[0011] In the attached diagram:

[0012] Figure 1AThis is a high-level schematic diagram of a pattern transfer (PTP) system according to some embodiments of the present invention.

[0013] Figure 1B and Figure 1C This is a high-level schematic diagram of the maintenance options and layout of a PTP system in a dual-channel production line according to some embodiments of the present invention.

[0014] Figure 2A and Figure 2B These are high-level side view and front view schematic diagrams of units and elements of a PTP system according to some embodiments of the present invention.

[0015] Figure 3A This is a high-level side view schematic diagram with a processing unit according to some embodiments of the present invention.

[0016] Figures 3B to 3E This is a high-level schematic diagram of a tape containing a pattern transfer sheet and a pattern transfer stage according to some embodiments of the present invention.

[0017] Figure 4 This is a high-level schematic diagram with reusable units according to some embodiments of the present invention.

[0018] Figure 5A and Figure 5B This is a high-level schematic diagram of a slurry filling unit according to some embodiments of the present invention.

[0019] Figures 5C to 5E This is a high-level schematic diagram of a printhead according to some embodiments of the present invention.

[0020] Figures 6A to 6C This is a high-level schematic diagram of a wafer processing unit and its operation according to some embodiments of the present invention.

[0021] Figure 6D and Figure 6E This is a high-level schematic diagram of a wafer measurement unit according to some embodiments of the present invention.

[0022] Figures 7A to 7C This is a high-level schematic diagram of a tensioning unit and a groove alignment monitoring unit according to some embodiments of the present invention.

[0023] Figure 8 This is a high-level schematic diagram of a print quality control unit according to some embodiments of the present invention.

[0024] Figure 9A This is a high-level flowchart illustrating the PTP method according to some embodiments of the present invention.

[0025] Figure 9BThis is a high-level flowchart illustrating the parallel processing procedures in a pattern transfer printing (PTP) method according to some embodiments of the present invention.

[0026] Figure 10 This is a high-level block diagram of an example computing device that can be used with embodiments of the present invention.

[0027] It will be understood that, for the sake of simplicity and clarity, the elements shown in the figures are not necessarily drawn to scale. For example, the dimensions of some elements may be enlarged relative to others for clarity. Furthermore, where appropriate, the same reference numerals may be repeated in the figures to indicate corresponding or similar elements. Detailed Implementation

[0028] Various aspects of the invention are described below. For clarity, specific constructions and details of the invention are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without the specific details set forth herein. Furthermore, well-known features may have been omitted or simplified so as not to obscure the invention. In specific reference to the accompanying drawings, emphasis is placed on the details shown as examples only and for illustrative purposes only, based on providing a description of the principles and concepts of the invention that is considered most readily and effectively understood. In this regard, no attempt is made to show structural details beyond those necessary for a basic understanding of the invention; the description, taken in conjunction with the drawings, enables those skilled in the art to clearly understand how various forms of the invention manifest in practice.

[0029] Before explaining at least one embodiment of the present invention in detail, it should be understood that the application of the present invention is not limited to the construction details and component arrangements set forth in the following description or shown in the accompanying drawings. The present invention is applicable to other embodiments that can be practiced or implemented in various ways, as well as combinations of the disclosed embodiments. Furthermore, it should be understood that the wording and terminology used herein are for illustrative purposes and should not be considered restrictive.

[0030] Unless otherwise specified, it will be apparent from the following discussion that throughout the discussion of the description, the use of terms such as “processing,” “computing,” “counting,” “determining,” “enhancing,” “deriving,” or similar terms refers to the behavior and / or process of a computer or computing system or similar electronic computing device that can manipulate and / or convert data (such as electronic quantities) in the registers and / or memory of the computing system into other data in similar physical quantities in the memory, registers, or other such information storage, transmission, or display devices of the computing system.

[0031] Embodiments of the present invention provide efficient and economical methods and mechanisms for pattern transfer printing, thereby providing improvements to the field of electrical contact generation, particularly to the field of photovoltaic cell production. Pattern transfer (PTP) systems and methods are provided to improve the quality, accuracy, and throughput of pattern transfer printing. The PTP system includes a tape handling unit for handling tapes with pattern transfer sheets, moving the tape from a feed roller to a take-up roller, and controllably feeding the pattern transfer sheets one by one for paste filling and continuous pattern transfer. The PTP system also includes: a paste filling device that can continuously fill paste using a support roller opposite to the paste filling head; a wafer handling unit that controllably feeds wafers for pattern transfer in parallel to increase throughput; and a paste transfer unit that has higher accuracy and efficiency due to precise monitoring and wafer alignment, as well as print quality control. The PTP system can be configured for a dual-channel configuration with two parallel wafer flows, allowing tape and paste replacement and maintenance in each system to be performed from its front side.

[0032] Figure 1A This is a high-level schematic diagram of a pattern transfer (PTP) system 100 according to some embodiments of the present invention. Figure 1B and Figure 1C This is an advanced schematic diagram of the maintenance options and layout of the PTP system 100 of a dual-channel production line 101 according to some embodiments of the present invention. Figure 1A This is a schematic forward-view stereoscopic view of the PTP system 100. Figure 1B This is a schematic perspective view of the front 102 of the PTP system 100, which is easy to maintain. Figure 1C This is a schematic top view of a PTP system 100 arranged with a dual-channel production line 101. Figure 2A and Figure 2B These are high-level side view and front view schematic diagrams of units and elements in a PTP system 100 according to some embodiments of the present invention. Figure 2A A highly schematic side view provides an illustration of the components in the processing unit 200 relative to the paste filling unit 120 (performing paste filling step 203) and the paste transfer unit 350 (performing paste transfer step 353, see example). Figure 2A and Figure 2B Non-restrictive examples of the arrangement of ), and Figure 2B The highly schematic front view provides a non-limiting example of the arrangement of components in the wafer processing unit 400 relative to the wafer processing unit 200. A brief description follows. Figure 2A and Figure 2B The units and elements shown are provided in further detail in a non-limiting embodiment within a series of figures. One or more control units 105 (see, for example) Figure 2A and Figure 2BIt can be configured as a unit to monitor and / or control the PTP system 100, possibly via various processors, and to coordinate the operation of the PTP system 100.

[0033] The PTP system 100 applies a pattern of conductive material onto a wafer using non-contact printing. The PTP system 100 includes a strip processing unit 200 for processing strips 205 (see, for example...). Figure 2A The belt 205 includes multiple pattern transfer sheets 205A, 205B, each having its own groove pattern, as segments thereof (see example...). Figure 2A The PTP system 100 also includes a pattern transfer sheet 205A for paste filling and a successive pattern transfer sheet 205B for pattern transfer, which can be controllably conveyed separately. The belt handling unit 200 is configured to move the belt 205 in a step-repeating manner (one sheet after another) from the feed roller 222 to the take-up roller 242. The PTP system 100 further includes a paste filling unit 120 configured to fill the grooves on the conveyed pattern transfer sheet 205A with conductive printing paste. The belt handling unit 200 can be further configured to feed pattern transfer sheets one by one for paste filling (indicated sheet 205A) and / or for pattern transfer (indicated sheet 205B), continuously monitoring tension and the machine orientation (MD, along the belt) and lateral machine orientation (CMD, perpendicular to MD) position of the belt 205. The PTP system 100 also includes a wafer handling unit 400 configured to controllably convey a plurality of wafers 90 (see, for example...). Figure 2B This allows for pattern transfer at a location very close to the pattern transfer sheet (e.g., within a range of 0.1 mm to 0.5 mm). The PTP system 100 also includes a paste transfer unit 350 configured to transfer the pattern via a laser beam 80 (e.g., ...). Figure 3A Under irradiation (as shown in the diagram), the printing paste is released from the trench to transfer the conductive printing paste from the corresponding pattern transfer sheet 205B to the corresponding wafer 90B in place.

[0034] The cells of the PTP system 100 are mounted in a compact manner on a rigid frame to minimize the system's footprint. As a general design feature, tape processing is performed along a vertical direction (indicated as "Z") and along a horizontal direction (indicated as "y", called the machine direction, MD), while wafer processing is performed along a direction perpendicular to it, for example, in another horizontal direction (indicated as "x", called the lateral machine direction, CMD).

[0035] The processing unit 200 can be configured to convey pattern transfer sheets (e.g., pattern transfer sheet 205A) one sheet at a time for paste filling by means of a moving paste filling head 122 in paste filling method step 203 and / or for pattern transfer (e.g., pattern transfer sheet 205B) by means of a moving scanning device 355 (e.g., an optical head movable along the x and y axes and optionally tiltable at an angle θ, or possibly scanning along the y axis, movable along the x axis and optionally tiltable at an angle θ), see example Figure 2A The following text provides details about tape 205 and the pattern transfer sheet thereon. Note that in Figure 2A In the diagram, the pattern transfer sheet 205A is schematically shown on the drawing plane, and it is located almost vertically in the paste filling unit 120. For example, the planes of the paste filling unit 120 and the pattern transfer sheet 205A can be set at an angle of 0-30° away from the vertical xz plane.

[0036] In some implementations, one or more top adjusters 225 and bottom adjusters 245 (see example) Figure 2A The feed rollers 222 and 245 can be configured to buffer the stepping and repetitive movements of the belt 205 from the feed roller 222 to the take-up roller 242, ensuring that these occur while the respective pattern transfer sheets 205A are in a stationary position, as the pattern transfer sheet 205A is filled with paste and / or the paste is transferred to the pattern transfer sheet 205B. The top adjuster 225 and / or the bottom adjuster 245 can be configured to maintain tension in the belt 205, wherein the belt movement passes through at least a portion of the PTP system 100.

[0037] It is worth noting that in the PTP system 100, the paste filling unit 120 is positioned almost vertically (along the Z-axis) to ensure a short travel distance from the paste-filled pattern transfer sheet 205A to the pattern transfer sheet 205B of the paste transfer unit 350, thereby minimizing changes in the state of the filling paste (e.g., due to pre-printing drying). For example, the near-vertical position can be configured to minimize the travel distance of the pattern transfer sheet from state 205A to state 205B, thereby optionally positioning the laser scanner directly behind the vertical filling unit, closer to the roller 227A located between 205A and 205B. Figure 2A The near-vertical position of the paste filling unit 120 is advantageous relative to the prior art horizontal position of the paste filling unit because it reduces the distance between the paste filling position (205A) and the paste transfer position (205B) of the pattern transfer sheet 205.

[0038] like Figure 1BAs schematically shown, the front side 102 of the PTP system 100 can be configured with easily accessible feed rollers 222 and take-up rollers 242 to meet replacement and maintenance requirements, and with an easily accessible slurry filling unit 120 (from the same front side 102) to meet slurry filling and maintenance requirements. Furthermore, as... Figure 1C As schematically illustrated, the PTP system 100 can be arranged back-to-back as a dual-channel production line 101, with each of the PTP systems 100A, 100B having easily accessible front sides 102 for maintenance. The dual-channel production line 101 can be configured to include two channels 101A, 101B, each channel having one or more (tandemly arranged) PTP systems 100A, 100B operating on two (or more) paths of the wafer 90 (e.g., independent paths for higher throughput), thereby using a relatively small footprint.

[0039] PTP system 100 may also include a reuse unit 250 (see example) Figure 2A The belt reusability unit 250 is configured to clean the pattern transfer sheet after pattern transfer to provide a reusable pattern transfer sheet. For example, the belt reusability unit 250 may include a belt cleaning unit 252, wherein the belt 205 can be cleaned mechanically, for example, using a scraper, ultrasonic waves, and / or other methods, and / or chemically using a cleaning solution; it also includes a belt drying unit 255 having idle rollers 244, 246 positioned as needed to maintain safe belt movement. The belt 205 may be moved by one or more belt drive motors 230 (schematically shown) and further supported by one or more rollers 227 along the path of the belt 205 through the PTP system 100. A non-limiting example of the belt handling unit 200 is shown below. Figures 3A to 3E More details are shown in the non-limiting example with reusable unit 250. Figure 4 More details are shown below.

[0040] Slurry filling unit 120 (see example) Figure 2A The slurry filling unit 120 may include a movable slurry filling head 122 and a movable opposing roller 125 configured to support the back side of the pattern transfer sheet 205A during slurry filling. A non-limiting example of the slurry filling unit 120 is shown below. Figures 5A to 5E More details are shown below.

[0041] In some embodiments, the wafer processing unit 400 may include at least one platform 410 (hereinafter referred to as an xz platform) movable along the x and z axes. Each platform 410 includes at least one retainer (e.g., a chuck) 415, and each retainer supports the wafer 90 and is capable of moving the wafer along the y and θ axes (the θ axis relates to the wafer's rotation about the xy plane). In some embodiments, the two xz platforms 410 of the wafer processing unit 400 may be configured to operate in parallel relative to each other. Each platform 410 may include two retainers 415 for holding the wafer 90, each retainer 415 ensuring movement of the wafer along the y and θ axes, thereby enabling faster wafer processing and continuous wafer movement during pattern transfer. Multiple cameras image the incoming wafer, enabling more accurate wafer alignment within the printing system, thereby more accurately aligning printed conductive lines onto the wafer pattern.

[0042] Chip processing unit 400 (see example) Figure 2B The device may include two platforms 410A and 410B, each platform 410 supporting two wafers 90, for example, via wafer holders 415A and 415B (e.g., vacuum chucks). Each platform 410 may support at least one wafer holder (chuck) 415, for example, two or three holders (chucks) 415. As a non-limiting example, two holders (chucks) 415A and 415B are shown for each of the two platforms 410A and 410B. Platform 410 may be configured to be movable along the x-axis and z-axis, while each holder (chuck) 415 may be configured to support the wafer 90 and be capable of additional wafer movement at least along the y-axis and θ-axis, as described below.

[0043] The wafer processing unit 400 can be configured to alternate between the two platforms 410A and 410B during operation to enable parallel operation of the wafer 90 by different units of the PTP system 100. For example, the position of wafer 90A can be measured by the wafer alignment unit 420, while wafer 90B receives paste transferred by the paste transfer unit 350 and wafer 90C is inspected by the print quality control unit 450, as disclosed herein. During the exchange of platforms 410, the two wafers 90 can be processed by their respective units, increasing the total throughput of the PTP system 100. For example, the wafer processing unit 400 can be configured to simultaneously provide: (i) wafer measurement of two wafers 90A (a first wafer and a second wafer, respectively mounted on holders (chucks) 415A and 415B on platform 410A), (ii) pattern transfer to a third wafer 90B (a holder (chuck) 415A mounted on platform 410B), and (iii) print quality control of a fourth wafer 90C (a holder (chuck) 415B mounted on platform 410B). The wafer processing unit 400 can then be configured to move platforms 410A and 410B according to arrow 411A, such that wafers are moved for continuous operation (e.g., wafer 90A is moved from wafer measurement to pattern transfer, wafer 90B is moved from pattern transfer to print quality control, wafer 90C is removed from the system, and a new wafer is transferred to wafer measurement). After moving along the linear platform of CMD, platforms 410A and 410B (arrow 411B) can be switched to further process wafer 90, and the movement cycle repeats, as follows. Figure 6C (Illustrative illustration).

[0044] The wafer processing unit 400 may also include mechanical components, such as an input wafer conveyor 412 for supplying wafers 90 and mounting them onto a wafer holder 415 of a corresponding platform 410, and an output wafer conveyor 419 for receiving printed wafers 90 from the wafer holder 415 of the corresponding platform 410. A non-limiting example of the wafer processing unit 400 and an illustrative description of its operation are provided in... Figures 6A to 6C It is shown in more detail below.

[0045] Wafer alignment unit 420 (e.g., 420A and 420B, see...) Figure 2B It can be configured to detect and measure features on the wafer and adjust the wafer position accordingly based on the pattern transfer—in Figure 6D and Figure 6E The non-restrictive examples are shown in more detail.

[0046] In some embodiments, the wafer processing unit 400 may include more than two platforms 410, with corresponding additions of the wafer alignment unit 420, paste transfer unit 350 and / or print quality control unit 450—to further increase the productivity of the PTP system 100.

[0047] PTP system 100 may also include a tensioning unit 270 (see example) Figure 2A and Figure 7A The tape stretching unit 270 is configured to fix and flatten the corresponding pattern transfer sheet 205B during paste pattern transfer from the pattern transfer sheet 205B to the wafer 90B. The PTP system 100 may also include a trench alignment monitoring unit 300, configured to monitor the position (e.g., in the x, y, and θ (tilt) directions) and deformation of the trenches prior to pattern transfer. Non-limiting examples of the tape stretching unit 270 and the trench alignment monitoring unit 300 are provided in... Figures 7A to 7C More details are shown below.

[0048] The paste transfer unit 350 (e.g., a laser scanning device) may include a laser scanning device (scanning head) 355 (e.g., movable along the CMD via a linear platform, ball screw platform, etc.), the laser scanning device (scanning head) 355 being configured to control the irradiation of the pattern transfer sheet 205B via a laser beam to deposit paste from the patterned grooves of the pattern transfer sheet 205B.

[0049] The PTP system 100 may also include a print quality control unit 450 (e.g., 450A and 450B, see below). Figure 2B This is configured to control the printing quality of pattern transfer, particularly to detect minute defects, such as openings or gaps within printed grid lines transferred onto the wafer, or other defects in the pattern. For example, the print quality control unit 450 may be based on an imaging camera, which transmits acquired images of the inspected wafer to a processor 452 for imaging processing. Non-limiting examples of the print quality control unit 450 are shown in... Figure 8 It is shown in more detail below.

[0050] Figure 3A This is a high-level schematic side view of a belt handling unit 200 according to some embodiments of the present invention. The belt handling unit 200 can be configured to move the belt 205 while sequentially feeding pattern transfer sheets 205A for paste filling (at the paste filling unit 120, see, for example...) by continuously controlling the belt tension and the precise position of the sheets in the MD and CMD coordinates. Figure 2A ) and / or for pattern transfer (in pattern transfer unit 350). Figures 3B to 3E It is a pattern transfer sheet 205B according to some embodiments of the present invention (see, for example) Figure 2A Advanced schematic diagram of the 205 and paste pattern transfer unit 350.

[0051] The CMD positions of the feed roller 222 and take-up roller 242 can be continuously controlled and corrected if necessary, with the assistance of one or more control units 105, for example, by controlling their drive motors. The top adjuster 225 and bottom adjuster 245 can be configured to support the rapid stepping movement of the pattern transfer sheets 205A, 205B (as segments of belt 205) to various positions of paste filling and pattern transfer. Idle rollers 227 (some indicated only) can be configured to guide the belt movement via the belt handling unit 200.

[0052] The tape processing unit 200 can be configured to quickly and accurately supply and replace tape segments (pattern transfer sheets) for printing wafers. The tape processing unit 200 can be further configured with a compact design that minimizes space requirements and is housed within a stable and rigid frame or chassis to support its operation and facilitate easy maintenance. The tape reuse unit 250 can be located within the frame and in the path of the tape 205, enabling the tape 205 to be reused—making the entire process more efficient and economical.

[0053] Figures 3B to 3E This is a high-level schematic diagram of a strip 205 with a pattern transfer sheet 205B and a pattern transfer unit 350 according to some embodiments of the present invention. Further details of the pattern transfer unit and the strip are disclosed in Chinese Patent Application Nos. 202111034191X and 202122130645.5, the entire contents of which are incorporated herein by reference.

[0054] Height indication Figure 3B This describes the use of laser illumination provided by a laser scanning device 355 to transfer patterned ink from a pattern transfer sheet 205B to a receiving substrate (e.g., a wafer) 90B. The pattern transfer sheet 205B includes a plurality of trenches 210 arranged in a specified pattern and configured to receive the printing ink and release the printing ink from the trenches 210 when the laser beam 80 irradiates the receiving substrate, such as the wafer 90B. Figure 3B and Figure 3E The diagram schematically illustrates the filling of grooves 110 on an empty pattern transfer sheet 205 with paste to create a filled pattern transfer sheet 205A, which is then further moved within the PTP system 100 to release paste from grooves 210 of the pattern transfer sheet 205B onto the wafer 90B. It should be noted that while the strip is generally designated by the numeral 205, segments of the strip 205 designed as pattern transfer sheets are designated by the numeral 205A when they are in the paste filling step 203, and by the numeral 205B when they are in the paste pattern transfer step 353 (in...). Figure 3B (Illustrated by an arrow).

[0055] The pattern transfer sheet may also include at least one trace mark 220 located outside the designated pattern of the groove 210 and configured to receive printing paste. The trace mark 220 is aligned relative to the corresponding groove 210 and is wider than the width of the laser beam 80. When irradiated by the laser beam 80, only a portion of the paste in the trace mark 220 (from the pattern transfer sheet 205B) is released because the width of the trace mark 220 is greater than the width of the laser beam 80, thus creating a gap that can be used to detect the actual position of the laser beam relative to the corresponding groove.

[0056] The pattern transfer sheet may also include multiple working window markers 223 located outside the designated pattern of the grooves 210 and configured to receive printing paste. The working window markers 223 are set with a specified offset relative to the designated grooves 210 of the designated pattern, wherein different working window markers 223 are set with different offsets. The working window markers 223 can be used to monitor the power of the laser beam 80 required to release paste from all grooves.

[0057] In some embodiments, the pattern transfer sheet may include trace markers 220 and working window markers 223, which may be configured to enable explicit detection via image processing (e.g., via groove alignment monitoring unit 300).

[0058] The pattern transfer sheet may also include a plurality of alignment marks (not shown) located outside the designated pattern of the groove 210, aligned with the corresponding groove 210, configured to receive printing paste, and used to provide initial alignment of the laser scanning device with respect to the designated pattern of the groove 210.

[0059] The groove alignment monitoring unit 300 can be configured to optically monitor the pattern transfer process, for example, by detecting the transfer of printing paste onto the substrate through the clearing of grooves 210 and marks 220, 223, as explained herein. One or more processors 356 or controllers (communicating with control unit 105) can communicate with one or more laser scanning devices 355 (in the paste transfer unit 350) and one or more imaging units 300, and are configured to adjust the optical parameters of laser irradiation by modifying the power and position settings of the laser scanning devices 355 based on image analysis of images captured by the imaging units 300. These adjustments and modifications improve the quality and accuracy of the pattern transfer step 353. For example, processor 356 or controller may be configured to calculate the alignment of laser beam 80 based on traces on the pattern transfer sheet (after paste is released from it), for example, detecting misalignment of laser scanning device 355 when asymmetrical traces are detected, as disclosed in Chinese Patent Applications Nos. 202111034191X and 2021221306455, which are incorporated herein by reference. Processor 356 and controller may also be configured to calculate the effective working window for laser irradiation using remaining working window markers 223 on the pattern transfer sheet (after paste is released from it), and adjust the laser power of laser scanning device 355 accordingly. Additional non-limiting details of the PTP system 100 are provided, for example, in U.S. Patent No. 9,616,524.

[0060] The disclosed PTP system 100 and band 205 can be used to print fine lines 92 formed from thick metal paste to create circuits, such as wires, pads, or other features on laminates for PCBs or other printed circuit boards, or on silicon wafers for photovoltaic (PV) cells, for example. Other applications may include creating conductive features during the manufacturing process of mobile phone antennas, decorative and functional automotive glass, semiconductor integrated circuits (ICs), semiconductor IC package connections, printed circuit boards (PCBs), PCB component assembly, optical, biological, chemical, and environmental sensors and detectors, radio frequency identification (RFID) antennas, organic light-emitting diode (OLED) displays (passive or active matrices), OLED lighting sheets, printed cells, and other applications. For example, in non-limiting solar energy applications, the metal paste may include one or more metal powders, optional glass frits and one or more modifiers, one or more volatile solvents and one or more non-volatile polymers and / or one or more resins. Non-limiting examples of pastes include those from Heraeus TM SOL9651B TM .

[0061] Figure 3CThis is a high-resolution cross-sectional schematic diagram of a strip (pattern transfer sheet) 205 according to some embodiments of the present invention. In some embodiments, the strip 205 may be transparent to allow laser irradiation and includes at least a top polymer layer 214, including grooves 210 and markings 220, 223 (in...). Figure 3B (Illustrated schematically), it is formed thereon by embossing, pneumatic forming or laser forming. In the non-limiting example shown, the cross-section of the groove 210 is shown as trapezoidal.

[0062] The band 205 may include at least one polymer layer, which may be selected from at least one of the following materials: polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, fully aromatic polyester, other copolyesters, polymethyl methacrylate, other copolyacrylates, polycarbonate, polyamide, polysulfone, polyethersulfone, polyetherketone, polyamide-imide, polyether-imide, aromatic polyimide, alicyclic polyimide, fluorinated polyimide, cellulose acetate, cellulose nitrate, aromatic polyamide, polyvinyl chloride, polyphenols, polyarylates, polyphenylene sulfide, polyphenylene ether, polystyrene.

[0063] It should be noted that, although the illustration Figure 3C Periodic grooves 210 are shown, but markings 220 and / or 223 ( Figure 3B (Illustrated schematically) may include grooves, recesses, and / or indentations imprinted into the top polymer layer 214 in a similar manner and may have similar or different profiles. For example, grooves 210, trace marks 220, and / or work window marks 223, as well as alignment marks, may have various profiles (cross-sectional shapes), such as trapezoidal, circular, square, rectangular, and / or triangular profiles. In various embodiments, the pattern of grooves 210 on strip 205 may include an array of continuous grooves 210 and / or separated indentations. It should be noted that the term "groove" should not be construed as limiting the shape of groove 210 to linear elements, but is understood broadly to include grooves 210 of any shape.

[0064] The strip 205 may include a top polymer layer 214 and a bottom polymer layer 212, the bottom polymer layer 212 having a melt temperature higher than the imprinting temperature of the top polymer layer 214. In some embodiments, the top polymer layer 214 may be made of a semi-crystalline polymer and have a melt temperature, for example, below 150°C, below 130°C, below 110°C, or an intermediate value. In some embodiments, the top polymer layer 214 may be made of an amorphous polymer and have a glass temperature below 160°C, for example, below 140°C, below 120°C, below 100°C, or an intermediate value. The bottom polymer layer 212 may have a melt temperature higher than the melt temperature or glass transition temperature of the top polymer layer 214. For example, the bottom polymer layer 212 may have a melt temperature above 150°C, above 160°C (e.g., biaxially oriented polypropylene), above 170°C, and up to 400°C (e.g., certain polyimides), or an intermediate value.

[0065] In some embodiments, the thicknesses of the top polymer layer 214 and the bottom polymer layer 212 (respectively) can be between 10 μm and 100 μm, for example, between 15 μm and 80 μm, between 20 μm and 60 μm, between 25 μm and 45 μm, or other intermediate values, with the bottom polymer layer 212 preferably being at least as thick as the top polymer layer 214. The polymer layers can be bonded by an adhesive layer 213 that is thinner than 10 μm (e.g., thinner than 8 μm, thinner than 6 μm, thinner than 4 μm, thinner than 2 μm, or intermediate values) and is also transparent to laser illumination. For example, in some embodiments, the top polymer layer 214 can be several μm thicker than the depth of the trench 210, for example, 5 μm, 3-7 μm, 1-9 μm, or up to 10 μm. For example, the trench 210 may be 20 μm deep, the top polymer layer 214 may be 20-30 μm thick, and the thickness of the bottom polymer layer 212 may be in the range of 25 μm to 45 μm (note that a thicker bottom polymer layer provides better mechanical properties). It should be noted that the term "trench" should not be interpreted as limiting the shape of the trench 210 to a linear element, but rather is understood broadly to include trenches 210 of any shape.

[0066] The temperature and thickness of the top and bottom polymer layers (214 and 212, respectively) can be designed so that the top polymer layer 214 has good molding properties, ductility, and a certain mechanical strength, while the bottom polymer layer 212 has good mechanical strength. Both the top and bottom polymer layers (214 and 212, respectively) can be designed to have good adhesive properties.

[0067] Figure 3D and Figure 3EThis is a high-level schematic diagram of a dynamic PTP system 100 according to some embodiments of the present invention. The dynamic PTP system 100 includes at least one laser scanning device (optical head) 355 configured to irradiate a pattern transfer sheet 205B with a laser beam 80, wherein grooves 210 are arranged in a first pattern 206 and hold printing paste in filled grooves 92, and then release the printing paste onto a wafer 90 upon irradiation by the laser beam 80 from the laser scanning device 355. The laser scanning device 355 is configured to have a rapid scanning axis along a machine direction 87 (y-axis, MD) and is movable along a transverse machine direction 85 (x-axis, CMD). The pattern transfer step 353 is performed by releasing the paste from the grooves, which in... Figure 3D and Figure 3E The arrows indicate the meaning.

[0068] The dynamic PTP system 100 may include a movable platform 410, to which a wafer holder 415 holds the wafer 90 (e.g., by vacuum suction clamping) during the release of printing paste 92 from the pattern transfer sheet 205B. The movable platform 410 may include any type of platform or wafer holder capable of holding and moving the wafer 90. The movable platform 410 may be moved by any type of actuator, such as a linear or stepper motor.

[0069] The dynamic PTP system 100 may also include a controller and / or processor 357, which may be associated with the control unit 105 and configured to control a laser scanning device 355 (e.g., an optical head) along the trench 20 (along the machine direction 87—MD) to guide the laser beam 80 and across the trench 210 along the transverse machine direction 85 (CMD, scanning direction). The processor 357 may also be configured to move a movable platform 410 (motion schematically represented by numeral 417) to generate a second pattern 96 of deposited paste on the wafer 90, which is different from the first pattern 206 of the trench 210 on the pattern transfer sheet 205B. Advantageously, compared to current practices which are limited to transferring the same pattern (e.g., lines) as the pattern transfer sheet 205B to the wafer 90, various embodiments of the dynamic PTP system 100 enable the transfer metal paste deposited onto the wafer 90 to have a pattern (second pattern 96) different from the first pattern 206 of the trench 210 on the pattern transfer sheet 205B.

[0070] like Figure 3EAs schematically shown, wafer 90B may include a pattern arranged at a generally parallel linear position with a specific receiving pitch p2 for receiving paste released from trench 210 of pattern transfer sheet 205B. Wafer 90B (e.g., in the range of 0.1 mm to 0.5 mm) is adjacent to pattern transfer sheet 205B, wherein a first trench on pattern transfer sheet 205B is positioned exactly opposite a first linear position on wafer 90B. The trench pattern 206 filled with paste on pattern transfer sheet 205B is sequentially scanned from the first trench to the last trench with laser beam 80, such that paste is deposited on designated positions on wafer 90B to produce a deposited paste of designated pattern 96. As processor 357 and / or control unit 105 moves wafer 90B during scanning (movement schematically indicated by numeral 417), paste is deposited at different pitches (p2 ≠ p1), which depends on the direction and speed of movement.

[0071] It should be noted that scanning along the x-axis can be performed in the forward and / or backward directions, and the corresponding movement 417 of the wafer 90 can be adjusted accordingly. In the case of this disclosure, the transverse machine direction 85 is shown as a direction as a non-limiting example.

[0072] For example, the first pattern 206 of the trench 210 on the pattern transfer sheet 205B may have a first pitch (“p1”), and the second pattern 96 of the deposited paste on the wafer 90 may have a second pitch (“p2”), which may be less than or greater than the first pitch (“p1”), for example, p1 > p2 or p1 < p2. It should be noted that the second pattern 96 may differ from the first pattern 206 over a portion of the wafer 90 or over the entire wafer 90. In some examples, pattern differences may include p1 > p2 in some regions of the wafer 90, while p1 > p2 in other regions of the wafer 90. <p2。

[0073] In some implementations, to make the first pitch p1 greater than the second pitch p2 (p1 > p2), the processor 357 can be configured to move the movable platform 410 along the scanning direction 85 (CMD, denoted as 417A) at a forward velocity set to convert the first pitch p1 into the second pitch p2. For example, the forward velocity is denoted as v. F And the time between continuous line depositions is expressed as t, p2 = p1 - v F •t. Alternatively or additionally, the scanning speed across trench 210 is expressed as v. S =p1 / t, the approximate relationship between the intervals is p2 = p1·(v S -v F ) / v S .

[0074] In some implementations, to make the first pitch p1 smaller than the second pitch p2 (p1 < p2), the processor 357 can be configured to cause the movable platform 410 to move in the opposite direction to the scan direction 85 (CMD) (denoted as 417B) at a backward velocity set to convert the first pitch p1 into the second pitch p2. For example, the backward velocity is denoted as v. B And the time between continuous line depositions is expressed as t, p2 = p1 + v B •t. Alternatively or additionally, the scanning speed across trench 210 is expressed as v. S =p1 / t, the approximate relationship between the intervals is p2 = p1·(v S +v B ) / v S .

[0075] Figure 4 This is a high-level schematic diagram of a reusable unit 250 according to some embodiments of the present invention. The cleaning unit 252 of the reusable unit 250 may include a pre-cleaning compartment 252A and a cleaning compartment 252B, configured to remove slurry residues with different properties (e.g., pre-cleaning can remove coarser slurry clumps, while cleaning can remove finer slurry residues), and may be fronted with a scraper device for removing slurry stains. Cleaning can be performed physically, such as by turbulent liquid flow, agitation, application of ultrasound, etc., and / or chemically, such as by applying a suitable solvent. The introduction of fluid into and out of the pre-cleaning compartments 252A and / or the cleaning compartments 252B can be managed by a recirculation unit 254 (schematically shown), including, for example, pumps and filters for reusing the respective cleaning solutions. A belt drying unit 255 may be located behind a belt cleaning unit 252 and configured to dry the belt 205 and prepare it for future use before winding it onto a take-up roller 242. Idle rollers 244, 246 and optional additional rollers may be configured to guide the belt movement through and after the belt reuse unit 250. During the belt segment advance movement, one or more idle rollers 248, shown at the bottom of unit 250, may move upwards to function as regulators (similar to regulators 225, 245) for smooth belt movement and continuous tension control. After the segment advance is complete, rollers 248 may descend due to their own weight. Alternatively or additionally, the belt reuse unit 250 may include one or more regulators configured to maintain tension on the belt 205 moving positively through the belt reuse unit 250.

[0076] Figure 5A and Figure 5B This is a high-level schematic diagram of a slurry filling unit 120 according to some embodiments of the present invention. Figure 5AIt's a 3D image. Figure 5B It is a side view. Figures 5C to 5E This is a high-level schematic diagram of a filling head 122 according to some embodiments of the present invention. Figure 5C and Figure 5E This is a schematic cross-sectional side view. Figure 5D This is a stereoscopic view taken from below the filling head 122.

[0077] like Figure 5A and Figure 5B As schematically shown, the slurry filling unit 120 may include a frame on which a slurry filling head 122 and a bottom roller 125 are mounted, and which move simultaneously relative to the frame. The movement of the slurry filling head assembly may be controlled by one or more control units 105, for example, by controlling a corresponding flexible frame 126 attached to the slurry filling head 122, the drive motor 124, and / or the frame motion system 128.

[0078] The bottom roller 125 can be configured to resist the paste filling head 122 and support the pattern transfer sheet 205A during paste filling of the pattern transfer sheet 205A by the paste filling head 122. The bottom roller 125 can be configured to roll during operation, possibly in a controlled manner.

[0079] The slurry filling unit 120 can be configured to rapidly, uniformly, and precisely fill high-viscosity slurry into trenches with a high aspect ratio. The slurry filling unit 120 can be further configured to clean the surface of the belt 205 after filling, for example, as disclosed in WIPO Publication No. 2015128857, which is incorporated herein by reference in its entirety.

[0080] like Figures 5C to 5E As schematically shown in, and further details disclosed in Chinese patent applications Nos. 2021106730065 and 2021213505781, which are incorporated herein by reference in their entirety, the filling head 122 of the slurry filling unit 120 may include: at least two supply openings 161, 169, an inner cavity 165, and at least one dispensing opening 160, which are in fluid communication (e.g., see...). Figure 5D and Figure 5EThe pressurized ink supply unit 155 is configured to circulate ink 190 through the printhead 150. The pressure in the pressurized ink supply unit can be regulated to maintain continuous circulation of ink through supply openings 161, 169 and the cavity 165 and to control ink dispensing through the dispensing opening 160. For example, the pressurized ink supply unit 155 may include an ink pump 152 and a pressurized ink reservoir 154 in fluid communication with the cavity 165 of the printhead 150, the pressurized ink reservoir 154 and the ink pump 152 configured to circulate ink. In a non-limiting example, the ink pump 152 may include a rotary pressure-sealed displacement system with a self-sealing rotor / stator design for dispensing precise volumes, such as those from DyMAX. TM eco-PEN450 TM .

[0081] In various embodiments, the slurry filling unit 120 includes at least one pressure sensor 140 configured to measure the pressure of the circulating slurry; for example, as a non-limiting example, in Figures 5C to 5E The pressure sensor 140, schematically shown and associated with the slurry mixer 130, or... Figure 5C Pressure sensors 140A and 140B are schematically shown at either end of the printhead 150. Alternatively or additionally, pressure measurement can be implemented within components of the pressurized slurry supply unit 155, such as the slurry pump 152 and / or the slurry reservoir 154. The slurry filling unit 120 may also include (in...) Figure 5E (Illustrated schematically) at least one controller and / or processor 167 (in) Figure 5E (Illustrated schematically), the at least one controller and / or processor 167 communicates with the control unit 105 and is configured to adjust the pressure in the pressurized slurry supply unit 155 (or a component of the pressurized slurry supply unit 155) based on a measured pressure of the circulating slurry. The slurry filling unit 120 may also include one or more slurry mixers 130 configured to mix the circulating slurry. The slurry mixer 130 may, for example, be a static mixer that mixes the slurry by utilizing its pressurization. In a non-limiting example, the slurry mixer 130 may include a disposable plastic static mixer made of a large-diameter plastic housing containing multiple mixing elements, such as those from Stamixco. TM GXF-10-2-ME TM .

[0082] The pressurized slurry supply unit 155 may also be configured to introduce slurry into the cavity 165 via at least one inlet opening 161 of the at least two supply openings and receive circulated slurry via at least one outlet opening 169 of the supply opening in the print head 150. Typically, the inlet opening 161 and outlet opening 169 are located at the top of the print head 150 opposite to the dispensing opening 160, which faces the pattern transfer sheet with grooves to be filled with slurry. Alternatively or additionally, the inlet opening 161 and / or outlet opening 169 may be located on the side and / or extension of the print head 150.

[0083] The pressurized slurry supply unit 155 may include a pressure-controlled slurry reservoir 154, a slurry pump 152, and a mixer 130, which are in fluid communication with each other. The pressure-controlled slurry reservoir 154 may be configured to deliver slurry to the slurry pump 152, which may be configured to deliver slurry to the inlet opening 161 via the mixer 130. The pressurized slurry supply unit 155 may be further configured to mix slurry exiting the outlet opening 169 with slurry delivered from the pressure-controlled slurry reservoir 154 to the slurry pump 152. For example, as... Figure 5C and Figure 5E As schematically shown, slurry 190 in slurry reservoir 154 can be conveyed (191) to slurry pump 152 and mixed (192) with slurry 197 exiting from outlet opening 169 of printhead 150 to be pumped into mixer 130 by slurry pump 152. Slurry 193 can be conveyed from mixer 130 to inlet opening 161 of printhead 150 (194), wherein slurry 196 moves along inner cavity 165, and some slurry 195 can be dispensed through dispensing opening 160 to form a pattern on transfer sheet 205A, such as lines subsequently (after tape movement, from transfer sheet 205B) printed on receiving substrate (e.g., wafer 90) (e.g., a pattern of silver grid lines about 20 μm wide on a silicon wafer for PV cells, see Lossen et al. 2015 as a non-limiting example). The remaining slurry 197 is then mixed with the slurry 191 from the slurry reservoir 154 (e.g., delivered via nozzle 163 at the junction 151) to compensate for the dispensing amount, and the slurry is circulated through the slurry filling unit 120 to maintain its mechanical properties and support continued mixing of the slurry to maintain its chemical homogeneity. In some embodiments, the slurry filling unit 120 may be further configured to alter the slurry composition, for example, by adding additives such as solvents, to maintain the homogeneity of the slurry, and pressure in the slurry filling unit 120 may also be monitored. For example, if desired, additives such as solvents may be added to the slurry entering the mixer 130.

[0084] In various embodiments, the dispensing slit, such as the opening 160 defined by the slit edge 162 (e.g., a metal slit lip), the printhead 150, and the cavity 165 can be elongated (see example...). Figure 5D It is constructed according to the slurry characteristics (e.g., viscosity value), the specified throughput and specified characteristics (e.g., length, width, and optional cross-section) of the lines or other elements dispensed by the printhead 150. In some embodiments, the dispensing opening 160 may include one or more slits, one or more openings, or a plurality of linearly arranged openings, such as one or more rows of circular or elliptical openings.

[0085] In various embodiments, the slurry may comprise a conductive silver-based metal slurry and is typically of high viscosity (e.g., in the range of tens to hundreds of Pa·s). For example, in non-limiting solar applications, the metal slurry may comprise metal powder, optional glass frit and modifiers, volatile solvents and non-volatile polymers and / or resins. Non-limiting examples of slurries include those from Heraeus TM SOL9651B TM .

[0086] The slurry filling unit 120 may include one or more pressure sensors 140, 140A, 140B configured to measure the pressure of the circulating slurry at one or more corresponding locations along the slurry circulation path. The pressure sensors 140, 140A, 140B may, for example, be configured to: be adjacent to the inlet opening 161, the outlet opening 169; be in fluid communication with the cavity 165 of the printhead 150; and / or be associated with any of the mixer 130, the slurry reservoir 154, and / or the slurry pump 152. Pressure-related indications from the pressurized slurry reservoir 154 and / or the slurry pump 152 may also be used to monitor slurry circulation through the slurry filling unit 120 and / or monitor and, possibly, modify slurry properties such as slurry viscosity, for example, by adding solvent. The slurry filling unit 120 may also include at least one controller (e.g., as part of or communicating with control unit 105) and / or as at least one computer processor 173, such as… Figure 10 As shown), the at least one controller communicates, for example, via a communication link with any component of the slurry filling unit 120, and is configured to adjust the pressure in the slurry reservoir 154 and / or the slurry pump 152 based on a measured pressure received, for example, from one or more pressure sensors 140, 140A, 140B of the circulating slurry. In a non-limiting example, any pressure sensor in the pressure sensor 140 may include, for example, a small-profile, media-compatible piezoresistive silicon pressure sensor (e.g., from TEconnectivity) encapsulated in a stainless steel housing. TMMEAS 86A TM (or equivalent sensor).

[0087] In various embodiments, the pressure-controlled slurry reservoir 154 and slurry pump 152 may open adjacent to the outlet opening 169 of the printhead 150, and the slurry filling unit 120 may include a conduit 135 connecting the outlet of the mixer 130 to the inlet opening 161 of the printhead 150. In some embodiments, the pressure-controlled slurry reservoir 154 and slurry pump 152 may open adjacent to the outlet opening 169 of the printhead 150, the mixer 130 may be adjacent to the inlet opening 161 of the printhead 150, and the conduit 135 may connect the slurry pump 152 to the mixer 130. A pressure sensor 140 may be associated with the mixer 130. The size and orientation of the slurry reservoir 154 and slurry pump 152 may vary; for example, both the slurry reservoir 154 and the slurry pump 152 may be configured perpendicular to the printhead 150 (see, for example, see...). Figure 5C Alternatively, one or both of the paste reservoir 154 and the paste pump 152 may be configured at an angle to the print head 150. For example, the paste pump 152 may be tilted to distribute the weight of the paste pump 152 more evenly across the print head 150, such as... Figures 5D to 5E The illustration is shown below.

[0088] In various embodiments, the conduit 135 can be adjusted to accommodate any arrangement of the slurry reservoir 154, the slurry pump 152, and the mixer 130 to make the slurry filling unit 120 more compact or to adjust the slurry filling unit 120 to meet given space and weight distribution requirements within the printing press. The retainer 145 is schematically illustrated (see, for example, [reference needed]). Figure 5C The retainer 145 serves as an attachment element for attaching the paste filling unit 120 to the printing press (for a non-limiting example, see, for example, U.S. Patent No. 9,616,524). In a non-limiting example, the conduit 135 may connect between the opening 131 in the mixer 130 and the opening 138 of the connector 137 located at the inlet opening 161 in the printhead 150 (see, for example, U.S. Patent No. 9,616,524). Figure 5C Alternatively, conduit 135 can be connected between opening 131 in slurry pump 152 and opening (inlet) 138 in mixer 130 (see, for example, [reference needed]). Figure 5E ).

[0089] Figures 6A to 6C This is a high-level schematic diagram of a wafer processing unit 400 and its operation according to some embodiments of the present invention. Figure 6A It is a side view. Figure 6B It is a partial 3D image. Figure 6C This is a schematic diagram of chip processing.

[0090] The wafer processing unit 400 is configured to increase the throughput of the PTP system 100 by processing different wafers 90 in parallel. Wafer holders 415A, 415B (see...) Figure 6B For example, a vacuum suction fixture can be configured to move in parallel (e.g., along the horizontal x-axis and the vertical z-axis) and perform wafer position correction along the horizontal y-axis and at a tilt angle (denoted as θ) relative to the wafer during movement. For example, each platform 410A, 410B can be configured to adjust two wafer holders 415A, 415B (which can adjust the wafer position) along the x-axis and z-axis. Accordingly, the wafer processing unit 400 may include one or more motors 413, such as a linear motor 413A (schematically shown) for moving platform 410A along the x-axis and a motor 418A (schematically shown) for adjusting the position of wafer platform 410A (with holders 415A and 415B) along the z-axis. The positions along the y-axis and θ-axis are adjusted by each holder 415 respectively. Therefore, a linear motor 413B (not shown), mounted parallel to motor 413A, moves platform 410B along the x-axis, and motor 418B adjusts wafer platform 410B (holders 415A and 415B) along the z-axis. Platforms 410A and 410B are operated parallel to each other along the x-axis by motors 413A and 413B, and are separated by motors 418A and 418B correspondingly changing their z-positions when moving in opposite directions.

[0091] In some embodiments, the wafer processing unit 400 may be configured to have two platforms operating in parallel, each platform being movable along the x and z directions. Each platform 410 may include two holders 415 for holding the wafer 90, each holder 415 ensuring the movement of the wafer along the y-axis and θ-axis (θ representing the rotation of the wafer about the xy-plane), thereby enabling faster wafer processing and continuous wafer movement during pattern transfer. Multiple cameras may be configured to capture images of the incoming wafer to achieve more accurate wafer alignment within the transfer system, thereby more accurately aligning the printed conductive grid lines onto the wafer pattern.

[0092] like Figure 6CAs schematically shown, the wafer processing unit 400 can be configured to move the wafer 90 from the input transport mechanism 412 through the pre-alignment platform (receiving the wafer at position 90A), the pattern transfer platform (receiving the wafer at position 90B), and the print quality control platform (receiving the wafer at position 90C) to the output transport mechanism 419, while parallel wafer processing allows the wafer supported by any of the platforms 410A, 410B to be processed in parallel. (For example, during pattern transfer 90B to wafer 1 on platform 1 (410A) (held by holder 415A), wafer 2 on platform 2 (410B) (held by holder 415B) can be pre-aligned (wafer 90A), while wafers 1 and 2 on platform 1 (410A) (held by holders 415A and 415B respectively) are pre-aligned (90A) and printed (90B), while wafer 1 on platform 2 (410B) (held by holder 415A) undergoes quality control (wafer 90C), and so on. The wafer processing unit 400 can be mounted on a granite base 405 (see example...) Figure 6B This stabilizes all modules and reduces inaccuracies that may be caused by frequent and rapid movements of the chip platform and other moving parts.

[0093] Wafer 90 may be a silicon wafer, for example, used to manufacture different types of PV cells, as described in detail, for example in Luque and Hegedus (EDS) 2011, Handbook of photovoltaic science and engineering, pp. 276-277, the entire contents of which are incorporated herein by reference.

[0094] Figure 6D and Figure 6E This is a high-level schematic diagram of a wafer alignment unit 420 according to some embodiments of the present invention. Each wafer 90A can be identified by its designated features, and its placement can be adjusted relative to the paste transfer unit based on the exact location of the designated features. For example, a selective emitter (SE) solar cell includes locally heavily doped lines (SE lines) on a silicon substrate, on which metal contacts are formed by paste transfer. The wafer alignment unit 420 can be configured to measure the position of the SE lines on the wafer 90A, and the wafer position can be adjusted such that paste transfer for each printed gate line is performed by the position of the paste transfer unit 350 relative to the SE lines, determined by the wafer alignment unit 420 to improve overall printing accuracy.

[0095] The wafer alignment unit 420 may include a camera array 430 with associated illumination, configured to measure the location of specific features on the wafer 90A, such as the location of SE lines. For example, the wafer alignment unit 420 may include multiple imaging cameras configured to capture at least a portion, possibly most or all, of the outer periphery of the wafer 90. The cameras in array 430 may be configured to image wafer corners (e.g., using four cameras for areas near wafer corners) and features in the middle of the wafer (e.g., using two or more cameras to image areas at two opposite ends of a specific feature, such as several trenches located in the middle of the wafer).

[0096] With each platform 410 having two wafer holders 415A, 415B for a corresponding wafer, the camera array 430 may include two corresponding subarrays 430A, 430B, for example, each subarray includes two rows of cameras, and each subarray is configured to measure wafer 90A at a corresponding location (e.g., as wafer 1 or wafer 2, such as...). Figure 6C (Illustrative illustration). In a non-limiting example, each camera subarray 430A, 430B may include six cameras 435 with corresponding illumination sources (e.g., four LED panels 422 of each subarray are configured to provide uniform illumination of the camera's field of view (FoV) with a high-contrast SE line image) – providing accurate x and θ coordinate values ​​of the SE line and the SE spacing even if the SE spacing is not uniform in the x-direction (CMD).

[0097] Camera array 430 can be mounted on a system base to ensure the stability and accuracy of its measurements. Processor 425 can receive images from camera array 430, apply high-resolution image processing algorithms to produce SE line measurements with an accuracy of one to several micrometers, and provide data to control unit 105 to adjust the position of the wafer relative to paste transfer unit 350. For example, camera 435 can be a 5Mpix CMOS type with an imaging lens, for example, a 25mm focusing length. It should be noted that the number of cameras 435 in each array 430 affects the accuracy of wafer-to-transfer sheet pattern alignment, thereby affecting the position of printed grid lines 92 on the SE lines of wafer 90B (see example...). Figure 3E As a non-limiting example, the number of cameras could be six, enabling the precise x, θ positions of the first and last SE lines to be determined by the four corner cameras, and the SE spacing along the CMD direction to be estimated with the help of the two intermediate cameras. In a non-limiting example, four LED panels 422 could be used to achieve uniform illumination of the FOV of all cameras through illumination close to the normal, enabling high-contrast imaging of the SE lines.

[0098] Figures 7A to 7CThis is a high-level schematic diagram of a tensioning unit 270 and a groove alignment monitoring unit 300 according to some embodiments of the present invention. Figure 7A It is a front view with an inserted side view (with 205 not shown). Figure 7B and 7C These are perspective views viewed from below (facing the front of the tensioning unit 270) and from above (facing the back of the tensioning unit 270 and the alignment monitoring unit 300). The tensioning unit 270 and the groove alignment monitoring unit 300 can be positioned relative to the plate 271 and fixed to the frame of the PTP system 100 by the support member 273.

[0099] The tape stretching unit 270 can be configured to stretch the tape 205 (e.g., the pattern transfer sheet 205B) during the pattern transfer step to keep the pattern transfer sheet (tape segment) 205B straight and flat, preventing deformation of the shape of the paste-filled grooves thereon and preventing direct contact between the pattern transfer sheet 205B and the wafer 90B on which the paste is transferred (e.g., maintaining a gap between the pattern transfer sheet 205B and the wafer 90B, for example, in the range of 100 μm to 500 μm). Furthermore, the tape stretching unit 270 can be configured to avoid interfering with wafer movement through the wafer processing unit 400. For example, Figure 7A and 7B The use of a vacuum bar 280 is schematically shown. The vacuum bar 280 is configured to fix and flatten the strip 205 using a vacuum application and stretching mechanism 275 and may include a groove 272 to apply a vacuum to the transfer sheet by maintaining its planarity.

[0100] The trench alignment monitoring unit 300 can be configured to monitor the x, θ position and deformation of the trench, for example, using multiple imaging cameras configured and / or positioned to capture the ends of the trench and at least the middle portion of the trench. For example, the trench alignment monitoring unit 300 can be configured to use camera 285 (e.g., four pairs of aligned cameras, one camera in each pair at each end of the trench) to measure the ends of the trench, and tilt camera 290 (see example...). Figure 7C A tilting camera 290 is shown, in Figure 7A The groove deformation in the middle of the groove is measured (shown at magnified scale in the partial side view on the left side of the image). The tilted imaging camera 290 can be tilted relative to the vertical z-direction to capture the middle portion of the groove without obstructing the illumination of the groove (e.g., not positioned above the pattern transfer sheet).

[0101] Corresponding image processing algorithms can be applied to the images from cameras 285, 290 in one or more processors 310 associated with control unit 105—to measure groove positions (e.g., x and θ positions) and deformations, and to optimize the positioning accuracy of laser beam 80 for some or each of the grooves filled with paste in pattern transfer sheet 205B during scanning. Measurements can be used to improve accuracy and / or reduce the required beam width (previously a wider beam 80 was used to compensate for inaccuracies). Groove alignment monitoring unit 300 may also include an illumination unit, such as an LED panel 287 located below the camera assembly (see, for example...). Figure 7A and 7C These are configured to provide the necessary trench illumination for the field of view of the respective cameras 285 and 290. In some embodiments, imaging cameras 285 and 290 may be assembled from the same CMOS camera and imaging lens used in the wafer alignment module.

[0102] The paste transfer unit 350 may include a high-power laser and an optical head 355, which form a laser beam 80 that releases paste from the grooves in the pattern transfer sheet 205B onto the wafer 90B.

[0103] The optical head 355 may be movable and configured to move along the CMD (x-axis), for example at a speed of approximately 0.5 m / s or higher. The optical head 355 is configured to focus the laser beam 80 onto a specified spot shape (effectively releasing paste from the grooves of the pattern transfer sheet 205B) and move this spot along the MD (y-axis) at a very high speed, for example, 500 m / s. The optical head 355 may move along the CMD (x-axis), for example, by adjusting the precise position of the laser beam 80 relative to the actual position of the grooves on the pattern transfer sheet 205B using a precise linear motor. (E.g., by the same or an additional motor) The optical head 355 may be controllably tilted to adjust the tilt of the pattern transfer sheet 205B, maintaining this tilt even during exposed tape stretching, and as measured by the groove alignment monitoring unit 300. The laser used in the pattern transfer unit 350 can be any of the following: a) CW, QCW, pulsed; b) infrared, near-infrared, visible light; c) solid-state, fiber optic, gaseous, laser diode. The scanning device for the MD axis can be a commercially available linear scanning device capable of scanning speeds of hundreds of meters per second. The motor assembly for the CMD axis movement of the optical head 355 can be based on a linear motor or a ball screw motor.

[0104] The paste transfer unit 350 can be controlled by the control unit 105 with respect to lighting and various motion parameters, which can be adjusted and monitored by the associated processor.

[0105] Figure 8This is a high-level schematic diagram of a print quality control (QC) unit 450 according to some embodiments of the present invention. The print quality control unit 450 can be configured to detect defects in pattern transfer using one or more cameras 455, which are configured to capture high-resolution images (e.g., having 20 megapixels or more) of the printed wafer 90C under appropriate lighting conditions (e.g., four dark-field LED panels along the X-direction—CMD, configured to provide uniform illumination across the entire wafer 90C). The print quality control unit 450 can be configured to provide high contrast and avoid or reduce optical noise.

[0106] The print quality control unit 450 may include two corresponding cameras 455A and 455B (the latter is schematically indicated by an arrow; camera 455B is opposite to camera 455A but...). Figure 8 (Not visible except in its FoV schematic diagram). Camera 455 is configured to be in the corresponding position (e.g., as chip 1 or chip 2, such as...). Figure 6C (Illustratively shown) Measuring wafer 90C. Processor 452 can receive images from camera 455, apply high-resolution image processing algorithms to detect minute printing defects, such as small cuts or localized printing errors, and provide the data to control unit 105 to correct process parameters. Cameras 455A and 455B, in a non-limiting example, can be 20Mpix CMOS type equipped with imaging lenses capable of achieving a field of view of approximately 230mm x 230mm. LED boards can be mounted on both sides and at two height levels to ensure uniform illumination of the entire wafer, such as... Figure 8 As shown schematically.

[0107] The elements in Figures 1-8 can be combined in any operable combination, and the illustrations of certain elements in some figures are not merely for illustrative purposes and are not restrictive.

[0108] Figure 9A This is a high-level flowchart illustrating a pattern transfer (PTP) method 500 according to some embodiments of the present invention. Figure 9B This is a high-level flowchart summarizing the parallel processes in a Pattern Transfer (PTP) method 500 according to some embodiments of the present invention. The method steps can be performed with respect to the described PTP system 100, which may optionally be configured to implement method 500. Method 500 may be implemented at least in part by at least one computer processor or by at least one control unit 105 (e.g., one or more personal computers, PCs, and / or one or more programmable logic controllers, PLCs, or combinations thereof). Some embodiments include a computer program product, including a computer-readable storage medium containing a computer-readable program and configured to perform the relevant steps of PTP method 500. PTP method 500 may include the following steps, regardless of their order.

[0109] like Figure 9A As shown, the PTP method 500 may include: processing a tape via a PTP system, the tape comprising a plurality of pattern transfer sheets as segments thereof, the pattern transfer sheets having their own groove patterns, to controllably transfer the pattern transfer sheets for paste filling (step 510); filling the grooves on the transferred pattern transfer sheets with conductive printing paste (step 520); controllably (one by one) transferring a plurality of wafers for pattern transfer (step 530); transferring the conductive printing paste of the plurality of groove-filled pattern transfer sheets to one wafer of the transport wafers by irradiating, for example, by scanning in the x and y two-dimensional directions with a laser beam to release the printing paste from the grooves (step 540).

[0110] PTP method 500 may also include cleaning the pattern transfer sheet after pattern transfer to provide a reusable pattern transfer sheet, and optionally reusing the cleaned pattern transfer sheet (step 560).

[0111] PTP method 500 may further include supporting the back side of the pattern transfer sheet by a relatively movable roller during slurry filling (step 522). PTP method 500 may further include performing groove filling in a nearly vertical position (step 524), for example, at a nearly vertical angle (ranging from 0 to 30° with respect to the vertical xz plane). For example, the slurry filling unit and the pattern transfer sheet plane may be set at an angle offset from the vertical xz plane by 0 to 30°.

[0112] PTP method 500 may further include using two alternating platforms to transport wafers, each platform supporting two wafers (step 532), controllably transporting the wafers to a position very close to the pattern transfer sheet (e.g., within a range of 0.1 mm to 0.5 mm) for pattern transfer (step 534), and simultaneously performing wafer measurement (before transfer), pattern transfer onto the wafer (during transfer), and printing QC inspection (after transfer) on at least three wafers (step 536), wherein at least two wafers are supported by the same platform. Wafers are then transported by continuously moving the platforms along the CMD. After the transferred wafers are released onto the output conveyor belt, these platforms can be alternated, and the printing process can be parallelized to increase throughput. In some embodiments, only two wafers (e.g., located on the same platform) are processed simultaneously, for a given pair of wafers, (i) exchanged between wafer alignment (before transfer) and pattern transfer onto the wafer (during transfer) and (ii) pattern transfer onto the wafer (during transfer) and printing QC inspection (after transfer).

[0113] PTP method 500 may further include fixing and flattening the corresponding pattern transfer sheet during pattern transfer (step 542) and / or monitoring the x, θ position and / or deformation of the grooves before pattern transfer (step 544).

[0114] PTP method 500 may also include detecting and measuring features on the wafer and adjusting the pattern transfer accordingly (step 546).

[0115] PTP method 500 may also include checking the printing quality of the transferred paste pattern (step 550), for example, by measuring the accuracy of the pattern transfer and / or detecting defects in the transferred pattern on the wafer.

[0116] like Figure 9B As shown, the PTP method 500 may include method steps implemented by the tape processing unit 200, the pattern transfer unit 350, and the wafer processing unit 400, as schematically shown and described in detail herein.

[0117] PTP method 500 may include moving a pattern transfer sheet from a feed roller to a paste filling unit (step 510A), filling grooves with paste (step 520), and moving the filled sheet to a pattern transfer unit (step 510B), such as stretching and securing the filled sheet in the transfer unit (step 542A), as disclosed herein. After removing paste from the sheet, PTP method 500 may include moving the used sheet to a reuse unit (step 514), cleaning and drying the sheet (step 560A), and moving the cleaned sheet to a take-up roller, possibly for future use (step 560B).

[0118] The PTP method 500 may further include: measuring the position of the trench by the trench alignment unit (step 544A), and scanning the trench with a laser to transfer the paste to the corresponding wafer 90 provided by the wafer processing unit (steps 540A, 540B, 540C, 540D) until the trench of the same sheet is laser scanned onto the last provided wafer (step 544B).

[0119] The PTP method 500 may further include processing the wafer using two platforms 410A and 410B, each platform performing the following steps: placing the wafer from the input transmitter onto the wafer holder (steps 530A and 530B), moving the wafer to the wafer alignment unit (steps 532A and 532B), determining the wafer position on the wafer holder (steps 534A and 534B), sequentially moving the wafer to the transfer unit, optionally during the previous wafer printing (steps 535A, 535B and 535C and 535D for the two platforms respectively), then moving the wafer to the print quality unit (steps 550A and 550B), then releasing the wafer to the output transmitter (steps 552A and 552B), and returning the platforms to their initial positions (steps 553A and 553B) to repeat steps 530-553.

[0120] Figure 10 This is a high-level schematic block diagram of an exemplary computing device 170 that can be used with embodiments of the present invention. The computing device 170 may include a controller or processor 173, which may be or include: for example, one or more central processing unit processors (CPUs), one or more graphics processing units (GPUs or general-purpose GPUs—GPGPUs), chips, or any suitable processing or computing device; an operating system 171; a memory 172; a storage system 175; an input device 176; and an output device 177. Any one and / or a portion of the PTP system 100, control unit 105, processors 310, 425, 452 may be or include a computer system, for example, such as... Figure 10 As shown. The processor may include multiple cores configured to process different tasks in parallel, such as processing images from all cameras in the wafer alignment unit and / or trench monitoring unit and / or print quality unit.

[0121] Operating system 171 may be or may include tasks designed and / or configured to perform operations involving coordination, scheduling, arbitration, supervision, control, or otherwise management of computing device 170, such as the execution of a scheduler. Memory 172 may be or may include, for example, random access memory (RAM), read-only memory (ROM), dynamic RAM (DRAM), synchronous DRAM (SD-RAM), dual data rate (DDR) memory chips, flash memory, volatile memory, non-volatile memory, cache memory, buffers, short-term memory cells, long-term memory cells, or other suitable memory cells or storage units. Memory 172 may be or may include multiple possible different memory cells. Memory 172 may store, for example, instructions for executing methods (e.g., code 174) and / or data such as user responses, interrupts, etc.

[0122] Executable code 174 can be any executable code, such as an application, program, process, task, or script. Executable code 174 can be executed by processor 173, possibly under the control of operating system 171. For example, according to embodiments of the invention, executable code 174 can cause computer code to be generated or compiled during execution, or executed by an application such as VR execution or inference. Executable code 174 can be code generated by the methods described herein. For the various modules and functions described herein, one or more computing devices 170 or components of computing device 170 can be used. Devices including components similar to or different from those included in computing device 170 can be used and can be connected to a network and used as a system. One or more processors 173 can be configured to execute embodiments of the invention by, for example, executing software or code.

[0123] Memory system 175 may be or may include, for example, a hard disk drive, floppy disk drive, optical disc (CD) drive, CD-R drive, Universal Serial Bus (USB) device, or other suitable removable and / or fixed storage unit. Data such as instructions, code, VR model data, parameters, etc., may be stored in memory system 175 and may be loaded from memory system 175 into memory 172, where it may be processed by processor 173. In some embodiments, Figure 10 Some of the components shown can be omitted.

[0124] Input device 176 may be, or may include, for example, a mouse, keyboard, touchscreen, or tablet computer, or any suitable input device. It will be appreciated that, as shown in box 176, any suitable number of input devices may be operatively connected to computing device 170. Output device 177 may include one or more displays, speakers, and / or any other suitable output device. It will be appreciated that, as shown in box 177, any suitable number of output devices may be operatively connected to computing device 170. Any suitable input / output (I / O) device may be connected to computing device 170, such as a wired or wireless network interface card (NIC), modem, printer or fax machine, universal serial bus (USB) device, or external hard drive may be included in input device 176 and / or output device 177.

[0125] Embodiments of the present invention may include one or more articles (e.g., memory 172 or memory system 175), such as a computer or processor non-transitory readable medium, or a computer or processor non-transitory storage medium, such as a memory, disk drive, or USB flash drive, encoding, including, or storing instructions, such as computer executable instructions, that perform the methods disclosed herein when executed by a processor or controller.

[0126] The various aspects of the present invention have been described above with reference to flowchart illustrations and / or partial diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each part of the flowchart illustrations and / or partial diagrams, and combinations of parts thereof, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, executable via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / actions specified in the flowchart illustrations and / or partial diagrams or their portions thereof.

[0127] These computer program instructions may also be stored in a computer-readable medium that can instruct a computer, other programmable data processing apparatus or other device in a particular manner to cause the instructions stored in the computer-readable medium to produce manufactured goods including instructions for functions / behaviors specified in flowcharts and / or partial diagrams or portions thereof.

[0128] Computer program instructions may also be loaded onto a computer, other programmable data processing apparatus or other equipment to perform a series of operational steps on the computer, other programmable apparatus or other equipment, thereby producing a process implemented by the computer. In this way, the instructions that execute on the computer or other programmable apparatus provide for implementing the functions / actions specified in the flowchart and / or partial diagram or parts thereof.

[0129] The foregoing flowcharts and schematic diagrams illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each part in the flowcharts or partial schematic diagrams may represent a module, segment, or code portion, which includes one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative embodiments, the functions indicated in this part may occur outside the order indicated in the figures. For example, two parts shown consecutively may actually be executed substantially simultaneously, or sometimes these parts may be executed in reverse order, depending on the functions involved. It should also be noted that each part of the partial schematic diagrams and / or flowcharts, and combinations of parts in the partial schematic diagrams and / or flowcharts, may be implemented by a system based on special-purpose hardware that performs the specified function or action, or by a combination of special-purpose hardware and computer instructions.

[0130] In the above description, embodiments are examples or implementations of the invention. Various presentations of “one embodiment,” “embodiment,” “some embodiments,” or “a number of embodiments” do not necessarily refer to the same embodiment. Although various features of the invention may be described in the context of a single embodiment, these features may also be provided individually or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment. Some embodiments of the invention may include features of the different embodiments disclosed above, and some embodiments may include elements of other embodiments described above. Elements of the invention disclosed in the context of a particular embodiment should not be considered as limiting to use in that particular embodiment. Furthermore, it should be understood that the invention can be carried out or practiced in various ways, and the invention may be implemented in some embodiments other than those outlined in the above description.

[0131] This invention is not limited to those figures or corresponding descriptions. For example, the process does not need to proceed through each shown box or state, or need to proceed in exactly the same order as shown and described. Unless otherwise specified, the technical and scientific terms used herein will be understood by one of ordinary skill in the art to which this invention pertains. Although the invention has been described with respect to a limited number of embodiments, these should not be construed as limiting the scope of the invention, but rather as examples of some preferred embodiments. Other possible variations, modifications, and applications are also within the scope of the invention. Therefore, the scope of the invention should not be limited by what has been described to date, but is limited by the appended claims and their legal equivalents.

Claims

1. A pattern transfer system, comprising: A belt processing unit is configured to process a belt comprising a plurality of pattern transfer sheets as segments thereof, the plurality of pattern transfer sheets having their own groove patterns, and the belt processing unit is configured to controllably convey the pattern transfer sheets for paste filling and sequential pattern transfer. A paste filling unit configured to fill conductive printing paste into grooves on the conveyed pattern transfer sheet; A wafer processing unit configured to controllably transfer at least one wafer to a position near the pattern transfer sheet for pattern transfer; A paste transfer unit is configured to transfer the conductive printing paste from the pattern transfer sheet to the wafer in place by releasing the conductive printing paste from the groove of the pattern transfer sheet filled with the conductive printing paste under the irradiation of a laser beam. The belt processing unit is configured to move the belt from the feed roller to the take-up roller in a step-by-step and repetitive pattern. The pattern transfer system further includes: A groove alignment monitoring unit is configured to monitor the position and deformation of the groove before the pattern transfer, wherein the groove alignment monitoring unit includes a plurality of first imaging cameras and at least two second imaging cameras, the plurality of first imaging cameras being configured to capture the ends of the groove, and the second imaging cameras being tilted relative to the vertical direction and configured to capture the middle portion of the groove; A wafer alignment unit configured to detect and measure features on a wafer and accordingly further adjust the wafer's position in the paste transfer unit, wherein the wafer alignment unit includes a plurality of imaging cameras configured to capture at least a portion of the wafer's outer periphery, the imaging cameras being configured to image features at the wafer's corners and center; and A stretching unit is provided, which is configured to fix and flatten the corresponding pattern transfer sheet during the pattern transfer.

2. The pattern transfer system according to claim 1, wherein, The processing unit is further configured to deliver the pattern transfer sheets one by one for paste filling and / or pattern transfer.

3. The pattern transfer system according to claim 1 or 2, wherein, The belt processing unit further includes at least one top adjuster and at least one bottom adjuster, the top adjuster and the bottom adjuster being configured to continuously maintain the tension of the belt.

4. The pattern transfer system according to claim 1 or 2 further includes a reusable unit configured to clean the pattern transfer sheet after the pattern transfer to provide a reusable pattern transfer sheet.

5. The pattern transfer system according to claim 4, wherein, The belt reuse unit includes a pre-cleaning compartment for removing slurry clumps, a cleaning compartment configured to remove fine slurry residues, and a drying unit for drying the belt before collection.

6. The pattern transfer system according to claim 5, wherein, The belt reuse unit further includes at least one regulator and / or roller configured to maintain the tension of the belt moving through the belt reuse unit.

7. The pattern transfer system according to any one of claims 1 to 2, 5 to 6, wherein, The slurry filling unit includes a movable slurry filling head and relatively movable rollers configured to support the back side of the pattern transfer sheet during slurry filling.

8. The pattern transfer system according to any one of claims 1 to 2, 5 to 6, wherein, The slurry filling unit is set at an angle within the range of 0-30° relative to the vertical axis.

9. The pattern transfer system according to any one of claims 1 to 2, 5 to 6, wherein, The wafer processing unit includes at least one platform capable of moving along the x-axis and z-axis, each of the at least one platform including at least one retainer, wherein each of the at least one retainer supports the wafer and enables the wafer to move along the y-axis and θ-axis.

10. The pattern transfer system according to any one of claims 1 to 2, 5 to 6, wherein, The paste transfer unit is configured to control the irradiation of the paste-filled grooves on the pattern transfer sheet by a laser beam.

11. The pattern transfer system according to claim 10, wherein, The irradiation of the slurry-filled trenches is performed one by one with the aid of an optical head that can perform laser scanning along the machine direction and can move along the transverse machine direction.

12. The pattern transfer system according to any one of claims 1 to 2, 5 to 6, and 11 further includes a print quality control unit configured to detect defects in the transferred pattern on the wafer.

13. A dual-channel production line comprising two pattern transfer systems as described in any one of claims 1 to 12, the pattern transfer systems being arranged back-to-back, each pattern transfer system having a feed roller and a take-up roller that are accessible for maintenance.

14. A pattern transfer method implemented by the pattern transfer system according to any one of claims 1 to 12, comprising: The pattern transfer system processes the belt and controllably conveys the pattern transfer sheet for paste filling and subsequent pattern transfer. The conductive printing paste is filled into the grooves on the conveyed pattern transfer sheet; Multiple wafers for pattern transfer can be controlled and transferred. as well as The conductive printing paste is transferred from the pattern transfer sheet to the conveyed wafer by releasing the conductive printing paste from the trench under the irradiation of a laser beam. The method further includes: Prior to the pattern transfer, a plurality of first imaging cameras and at least two second imaging cameras are used to monitor the position and deformation of the grooves. The plurality of first imaging cameras are configured to capture the ends of the grooves, and the second imaging cameras are tilted relative to the vertical direction and configured to capture the middle portion of the grooves. Multiple imaging cameras are used to detect and measure features on the wafer and accordingly adjust the transfer of conductive printing paste from the pattern transfer sheet to the conveyed wafer. The multiple imaging cameras are configured to capture at least a portion of the outer periphery of the wafer, and are configured to image features at the corners and center of the wafer; and During the pattern transfer process, the corresponding pattern transfer sheet is fixed and flattened.

15. The pattern transfer method according to claim 14, further comprising: Continuously monitor belt tension and belt position.

16. The pattern transfer method of claim 14 or 15 further includes cleaning the pattern transfer sheet after pattern transfer to provide a reusable pattern transfer sheet.

17. The pattern transfer method according to claim 14 or 15, further comprising supporting the back side of the pattern transfer sheet by a relatively movable roller during paste filling.

18. The pattern transfer method according to claim 14 or 15, further comprising: Simultaneously perform pre-printing wafer measurement, pattern transfer on wafers during printing, and post-printing quality control checks on at least three wafers, wherein at least two wafers are supported by the same platform.

19. The pattern transfer method according to claim 14 or 15 further includes checking the quality of the transferred paste pattern.

20. The pattern transfer method according to claim 14 or 15 further comprises arranging two of the pattern transfer systems back-to-back as a dual-channel production line, the dual-channel production line having parallel wafer transport, the belt, feed roller and take-up roller being configured to be accessible for replacement and maintenance from the front side of each pattern transfer system.

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