Thursday, March 12th, 2009
Stangl Semiconductor Equipment has launched its Linea horizontal inline wet process platform for cleaning and etching of crystalline silicon PV wafers. The fully-automated dry-in/dry-out system offers reliable production capacity of up to 3,400 wafers per hour (wph) corresponding to an estimated 60 MW per line running 156mm wafers. The system can also be configured at 1,700 wph and then doubled. The tool was first shown at Photon’s 4th Photovoltaic Technology Show 2009 Europe in Munich.
To reach such high throughput levels, essential for low-cost solar cell manufacturing, handling of wafers as thin as 150 microns must be managed carefully. The tool is based on two newly developed sub-systems for transport and chemical flow, though no information on beta tests was available at the time of this posting.
Linea inline wet processing (source: Stangl)
The continuous inline process transport (see figure) and the overall wafer handling are designed to ensure a low breakage rate. When wafers eventually break, and at high volume the odds say it’s only a matter of time, the handling systems must be cleanable and unbreakable. The wafer transport sub-system uses a motor-driven plastic conveyor chain to smoothly move O-ring-based belt transfer sections. Gentle motion of 156 mm or 125 mm wafers minimizes mechanical wafer stress across up to 6 parallel transport lanes.
The chemical flow sub-system reaches both high uniformity and reduced chemical consumption. Spray nozzles deliver chemicals to wafer top sides, and careful control of chemical flows, rinse water flows, and dry gas flows allow for effective isolation between inline process sections. Well designed continuous processing tools are the way to go to get to cost-effective high volume. –E.K.