Dear Colleague,
I checked the metal wire with microscope and found that the sputtered
Cr wire looks like broken into lots of small domains. As my wire is
10um wide, I think that this kind of damage will cause the
disconnection in metal lines. This damage may be caused by my
substrate of 5um exposed Su-8 on top of silicon wafer. The thermal
cycle due to the sputtering can cause the deformation of the SU-8,
therefore the breaking of the metal lines. Did anyone meet this
problem before?
Oxidation may be another reason as suggested in reponse of several
collegues to my question (thank you very much). The reason I can't
deposite two layers together is that I do not allow two metal layers
stacked together. Essentially I want the lines of two metals seriously
connected. If I have to deposite the two metal seperately, what
measures can I take to reduce the oxidation in between?
I really appreciate your help.
Li Wang