Legal Question in Technology Law in Texas

You posted this question in the wrong category. It belongs under General Civil Litigation instead. But it's pretty straightforward, so I will answer it here.

Witnesses can only take the Fifth if their answers might expose them to criminal prosecution. Exposure to civil liability is not enough. The rule is the same in court and in depositions.

We usually think of patent infringement as a civil matter. But actions that infringe patents are sometimes also crimes. You should consult with a lawyer about whether and how you may invoke the Fifth Amendment in your circumstances.