I have gone through countless literature articles pertaining to sol gel TCO coatings. The theme in each is to dissolve a metal salt (such as zinc acetate doped with aluminum chloride) in ethanol (et al) while using a complexing agent such as ethanolamine or ethylene glycol to help form the gel. To form the coating a glass slide is coated with the sol gel, dried at moderate (~120C) temperatures (this process is repeated for additional layers) and then finally pyrolyzed / annealed at ~400C for a couple hours. The resulting slide *should* be transparent and conductive.
The problem is that each time I pyrolyze the slide the surface immediately turns into an ugly dark charred mass - certainly not a thin layer of AZO like I intended. I don't understand how I could follow the exact same methods as everyone else but have such bad results.
Any ideas why this is happening or what I'm doing wrong?
Thanks!