Hello, I'm currently working on improving a wet-etch process that uses ferric chloride as an etchant and stainless steel as a substrate. The current photoresist in use is positive, but I'm looking to test several negative photoresists.

Here's my question: I've seen some research papers that use the Ohnishi parameter and the Ring parameter to quantify etch resistance in resins for dry-etch techniques. Is there a similar way to determine etch resistance for wet-etching or is it just based on observations?