Patent ID: 8586129

Claim:
A method for producing an H-pattern solar cell structure including a plurality of parallel gridlines on an upper surface of a target substrate using a micro-extrusion system, the micro-extrusion system including: an extrusion printhead assembly, a material feed mechanism for controllably supplying gridline material to said extrusion printhead assembly such that said gridline material is selectively forced from a plurality of dispensing orifices of said extrusion printhead assembly, and a transport mechanism for supporting the extrusion printhead assembly and said target substrate, and for moving the extrusion printhead assembly relative to said target substrate such that said gridline material exiting said plurality of dispensing orifices forms said plurality of parallel gridlines on the upper surface of the target substrate, wherein the method comprises: during a first time period, causing said material feed mechanism to force said gridline material through said plurality of dispensing orifices while causing said transport mechanism to move said extrusion printhead assembly relative to said target substrate such that first endpoint structures are formed on said target substrate adjacent to a first side edge of said target substrate, wherein each said first endpoint structure has a nominal first width; and during a second time period following the first time period, causing said material feed system to force said gridline material through said plurality of dispensing orifices while causing said transport mechanism to move said extrusion printhead assembly relative to said target substrate such that central gridline portions are formed that extend across the target substrate, wherein each said central gridline portion is integrally connected to an associated one of said first endpoint structures and has a nominal second width that is smaller than the nominal first width, further comprising, during a third time period following the second time period, causing said material feed system to force said gridline material through said plurality of dispensing orifices while causing said transport mechanism to move said extrusion printhead assembly relative to said target substrate such that second endpoint structures are formed on said target substrate adjacent to a second side edge of said target substrate, wherein said second endpoint structures is integrally connected to an associated one of said central gridline portions and has a third nominal width that is greater than the second nominal width before said first time period, forming one or more busbars on said target substrate; and during said second time period, causing said material feed system to force said gridline material through said plurality of dispensing orifices while causing said transport mechanism to move said extrusion printhead assembly relative to said target substrate such that said central gridline portions include vertex portions that extend across the one or more busbars.