we deposit Aluminum on conjugated polymer surfaces to develop the cathode on the solar cell.
the structure of a typical device is: Glass/ITO/PEDOT:PSS/(P3HT:PCBM blend)/LiF/Al
LiF is not present all the cases but mostly. the evaporation is done thermally using tungsten filaments, the vac. level is ~5e-7mbar. all this happens in a glove box (N2 atmosphere)
1- what are the conditions (parameters) that would result in a uniform dense coating
2-does the Al vapors damage the polymer (conjugation etc)
3-how can we minimize damage to the polymer/Al interface (if any) due to the hot Al flux or extra heat produced by the filaments
suggestions are highly appreciated. thanks in advance