Simultaneously Writing Bus Bars And Gridlines For Solar Cell

A method for forming on a target substrate a plurality of parallel gridlines that extend in a first direction across a surface of the target substrate, and one or more bus bar structures that extend in a second direction across the surface of the target substrate, the second direction being generally perpendicular to the first direction, the method comprising:

• positioning a multi-nozzle extrusion printhead assembly over the surface of the target substrate such that a plurality of nozzle outlets of the printhead assembly are positioned adjacent to and parallel with a first edge of the target substrate;
• and
• while causing said printhead assembly to continuously extrude material such that a plurality of beads of said extrusion material are directed toward said target substrate, each said bead being extruded from a corresponding one of said plurality of nozzle outlets, sequentially moving said printhead assembly relative to the target substrate:
• in the first direction such that first portions of said extruded beads are deposited on the surface and form parallel first gridline sections extending away from said first edge,
• in the second direction such that second portions of said extruded beads are deposited on the surface in a way that collectively forms a first bus bar structure extending generally parallel to said first edge, and
• in the first direction such that third portions of said extruded beads are deposited on the surface and form second gridline sections extending parallel to the first gridline sections.

A method for forming on a target substrate a plurality of parallel gridlines that extend in a first direction across a surface of the target substrate and one or more bus bar structures that extend in a second direction across a surface of the target substrate, the second direction being generally perpendicular to the first direction, the method comprising:

• positioning a multi-nozzle extrusion printhead assembly over the surface of the target substrate such that a plurality of nozzle outlets of the printhead assembly are positioned adjacent to and parallel with a first edge of the target substrate;
• and
• while continuously extruding material from said printhead assembly such that a plurality of beads of said extrusion material are directed toward said target substrate, each said bead being extruded from a corresponding one of said plurality of nozzle outlets:
• moving said printhead assembly relative to the target substrate in the first direction at a first speed such that first portions of said extruded beads are deposited on the surface and form parallel first gridline sections extending away from said first edge;
• moving said printhead assembly relative to the target substrate in the first direction at a second speed, said second speed being slower than said first speed, while reciprocating said printhead assembly relative to the target substrate in the second direction such that second portions of said extruded beads are deposited on the surface in a way that collectively forms a first bus bar structure extending generally parallel to said first edge;
• and
• moving said printhead assembly relative to the target substrate in the first direction at the first speed such that third portions of said extruded beads are deposited on the surface and form second gridline sections extending parallel to the first gridline sections.