The chips used for surface plasmon resonance are fairly expensive. Does anyone know what nanofabrication techniques are used to make the chips? I've been told they are relatively easy to make if one has access to a nanoscale facility.
Surface plasmon resonance (SPR) is a phenomenon that occurs on any metal surface. You need no chips to observe it. It looks like you are talking about some particular application of SPR, but you should be more specific.
I'm planning to measure the rate constant of a specific reaction. I don't completely understand surface plasmon resonance, but don't you need to coat a chip with some gold or silver in order to proceed?
In your case, you deal with a chemical detector based on the sensitivity of the SPR band position to the chemical environment of the metal. Gold and silver are indeed used most often due to their small losses and high chemical stability. You can make metal nanoparticles by very simple techniques but I ignore how the chips for your particular application are made. Just a guess: metal ion implantation in a glass surface? There are also purely chemical routes.