Abstract: Pattern transfer printing (PTP) systems and methods are provided to improve the quality, accuracy and throughput of pattern transfer printing. PTP systems comprise a tape handling unit for handling a tape with pattern transfer sheets sections and for controllably delivering the pattern transfer sheets one-by-one for paste filling and consecutively for pattern transfer, with the tape moving from an unwinder roll to a re-winding roll. PTP systems further comprise a paste filling unit which enables continuous paste filling using a supporting counter roll opposite to the paste filling head, a wafer handling unit controllably delivering wafers for the pattern transfer in a parallelized manner that increases throughput, a paste transfer unit with enhanced accuracy and efficiency due to exact monitoring and wafer alignment, as well as a print quality control unit.

Abstract: Pattern transfer sheets and methods are provided, providing multi-layer paste stack lines that are printed on a receiving substrate in a single illumination step. The paste is filled layer-by-layer, possibly having different materials in different layers, with layer thickness controlled by parameters of the filling elements, e.g., in case of blades, the pressure, angle, velocity and flexibility (material) of the blade. Specifically, a bottom layer of the stack may be configured to interface the receiving substrate while one or more top layers may be configured to optimize the quality of the printed features. For example, bottom layers may comprise to bind to the substrate, to modify the substrate (e.g., forming selective emitter (SE) therein) and/or provide a barrier from top layer(s) which may not be compatible with the substrate (e.g., copper on silicon). Releasing material may be used to support the single step release of the stack line.

Abstract: Pattern transfer printing (PTP) systems and methods are provided to improve the quality, accuracy and throughput of pattern transfer printing. PTP systems comprise a tape handling unit for handling a tape with pattern transfer sheets sections and for controllably delivering the pattern transfer sheets one-by-one for paste filling and consecutively for pattern transfer, with the tape moving from an unwinder roll to a re-winding roll. PTP systems further comprise a paste filling unit which enables continuous paste filling using a supporting counter roll opposite to the paste filling head, a wafer handling unit controllably delivering wafers for the pattern transfer in a parallelized manner that increases throughput, a paste transfer unit with enhanced accuracy and efficiency due to exact monitoring and wafer alignment, as well as a print quality control unit.

Abstract: Pattern transfer sheets and methods are provided for printing paste patterns (e.g., thin fingers) with a high aspect ratio and for increasing throughput in pattern transfer printing. Trenches in the pattern transfer sheets, that are configured to be filled with printing paste and to enable releasing the printing paste from the trenches onto a receiving substrate upon illumination by a laser beam—are coated internally by a coating configured to disintegrate upon the illumination. The coating is configured to enhance the releasing of the paste—increasing throughput and printing accuracy. The receiving substrate may be cleaned after paste deposition by removing disintegration products of the coating therefrom. Alternatively or complementarily, laser absorbing dye may be mixed into the printing paste to facilitate its release from the trenches.

Abstract: Dynamic pattern transfer printing systems and method are provided, which decouple the design of the trench patterns on a source substrate for pattern transfer printing, from the resulting metallic paste lines patterns transferred to a receiving substrate, such as PV cells. The receiving substrate may be moved forward (along the scanning direction of the laser illumination used to transfer the paste from the trenches onto the receiving substrate) to reduce the pattern pitch with respect to the source substrate, and/or the receiving substrate may be moved backward (against the scanning direction) to increase the pattern pitch with respect to the source substrate. For example, dynamic pattern transfer printing may be used to accommodate different widths of the substrates for more effective pattern transfer, and/or to enable one-to-many pattern transfer technologies with high wafer throughput. Also, pattern transfer sheet with separate multiple groups of trenches are provided.

Abstract: Pattern transfer sheets, methods of monitoring pattern transfer printing, and pattern transfer printing systems are provided, for monitoring and adjusting laser illumination used for transferring paste patterns from trenches on the sheets onto a substrate such as electronic circuitry and/or solar cell substrates. Pattern transfer sheets comprise, outside the pattern, (i) trace mark(s) configured to receive the printing paste, aligned to the trenches and are wider than the width of the illuminating laser beam—to detect misalignment of paste release from within the trace mark(s) and/or (ii) working window marks configured to receive the printing paste, set at specified offsets with respect to specific trenches, with different working window marks set at different offsets—to correct the effective working window by adjusting the power of the laser beam.