Hallo all,
I'm doing some tests with a heating structure from tungsten-titanium alloy,
above which there is a silicon nitride layer for passivation. A room temperature
fluid is applied on the SiN layer. It had worked ordinarily with resistance c.a.
1 kohm for around 5 hours, then the resistance suddenly jumped to 380 kohm,
which seems nearly brocken. Acctually the current was constantly observed to be
5 mA before the drastic change.
What could be the problem? Any advice would be appreciable.

win2