Laser patterning
Patterning, etching, isolation of conductive thin films, grooves in silicon layers for contacting ...
4 etching-lasers are available in SOLEMS :
2 YAG 1.064µm lasers with Q-switch (pulsed lasers) supplying short pulses of power for selective etching of oxides layers : SnO2, ITO, ZnO ...etc...
2 double-frequency YAG lasers (532nm) also pulsed for silicon films etching.
The optical fiber driving the laser power is placed on a X-Y table moving tool. The patterning drawn on the thin films is therefore entirely programmable.
It is a sublimation process : the material is removed from its substrate, directly transformed into vapor by the heat generated by the laser pulse. By tuning the laser intensity, the Q-switch frequency, the tool speed, it is possible to get either a continuous isolation line, or separate spots, for example to perform a top-bottom electrical contact through a layer.
This technique is namely used to :
isolate conductive areas on a TCO (transparent conducting oxide)
cut very hard ceramic layers without contact
ensure the series connection of neighbouring cells on a thin film solar cell or module by contacting metal (-) and TCO (+) of the 2 cells through the holes made by laser in the silicon layer
Concerning the use of this process in SOLEMS products, see :
Apply to us for any request.