ASSP-22 – Al/ZnO Sputtering System
The Al/ZnO Sputtering System (ASSP) forms the rearmost conducting layers in photovoltaic modules. It uses physical vapor deposition (PVD) to sputter zinc-oxide and aluminum layers. The first one diffracts the sun light, while the latter one reflects it back to the amorphous silicon layer to increase the module’s efficiency. An 11.5 m long and nearly 8 ton machine that is a composition of 6 individual chambers – it can handle multiple panels at once.
The Sputter is entirely PLC controlled. The only manual operation is the sample load and unload in the case the automatic loader/unloader is not present. The system operator can follow the process on a single monitor with the help of a graphical user interface. The glowing plasma can be observed directly through shutter windows. A two-stage vacuum system provides uninterrupted PVD for both the zinc-oxide and the aluminum layers. The whole machine is designed to carefully secure the cleanness of the PV panels, thus minimizing refuse, ensuring an even layer deposition, and maximizing productivity.
|L × W × H:||11500 × 2200 × 2400 mm|
|Work piece:||1245 × 635 mm (thickness: 3.0 ~ 3.3 mm)|
|Cycle time:||under 75 sec (continuous sequential operation)|
|Process gases:||Ar, N2, O2|
|Load/unload:||manual or by panel lifter|
|PLC based safety interlock and process control system|
|Linear magnetron sputter source with 2×10 kW DC supply for Al|
|Rotating magnetron sputter source with 30 kW DC for ZnO|
|MFC controlled process gas inlet|
|Fore vacuum and high vacuum system|
|End vacuum: better than 2×10-6 mbar|
|Leakage: less than 2×10-9 mbar l/sec|
|Standard components from Pfeiffer, HSR and VAT|