Silver paste is forced through a patterned screen. Those areas with gaps in the pattern leaves a metal pattern on the surface.
Screen printer in operation. The cells move along a conveyor belt. Here they enter on the right and exit on the left.
Close up of the screen printing operation. The cells are undernearth the printer so are not visible from the top.
After printing the paste is still wet and is easily smudged. Here the wafers are loaded into a drier to evaporate off the organic binders in the paste. Driers operate at a low temperature of around 200 °C.
After the wafers are dried they are loaded back onto the conveyor belt to continue their movement in through the production line.
Zooming in on a cell after the front screen print is finished. At this stage, the silver still exists as a powder resting on the cell. A later firing process at high temperature bonds the silver to the silicon.