Hi everybody,

We need some advice, critics or suggestion.

We are trying to thermally evaporate Al layers on glass substrates. We are
using Tungsten filaments in spring form and holding the Al filaments inside
the Tungsten spring. Our vacuum arrives to 10^(-6) mbar and the DC current
is gradually raise to 18-20A (the tungsten filament becomes incandescent),
we keep the DC current until we don't see any Al inside the tungsten spring..
Apperently everything is right and the first days we achieved some
acceptable layers, but after a few days the Al layers are extremelly thin
(almost invisible).

Maybe the chamber is dirty? Any possible treatment for cleaning it?

Thanks in advance.

Regards

--
Rafael García Valverde, PhD
Electronics Department - DETCP
Technical University of Cartagena - UPCT
Plaza del Hospital, 1 30203
Cartagena, Murcia SPAIN
(0034)  868888787 / 968326514