Dear colleagues,

I am currently utilizing combinations of photo- and dark-current for the
fabrication of structures.

With dark-current, I use either galvanostatic or potentiostatic modes.

With potentiostatic mode, however, it seems my reference voltage, Vsce, goes
out of control. I have intuitively related this condition to the gases
produced. I assumed that the gases screen the semiconductor from the electro-
lyte. The result, I assumed, is charge build-up, leading to high field
gradient. This high field gradient appears as uncontrollable Vsce. My
assumption is sort of confirmed in the sense that whenever I dislodge the
bubbles from the surface, the Vsce mementarily drops.

My question is how can this problem be resolved. I am investigating using
elecrochemically passive chemicals to either annihilate the bubbles as they
form or simply dislodge them.

I would appreciate helpful contributions to this and related issues.

Thanks,

Robert Okojie,
Microelectronics Research Center,
NJIT,
Newark, NJ