Hello, I am wondering if anyone knows whether the refractive index of SU 8-2000 at 1550 nm wavelength (or 850 nm) will increase or decrease after cross-linking (i.e. after post-exposure-bake/hard bake)? I would definitely appreciate it if some references can be given as well. I checked with MicroChem but they had no idea about the optical properties... Thank you very much! Best regards, JJ Hu