Can the viewport rect of a camera be static?

So I have this camera which is for the minimap of my game, I want to know if it's possible to keep it in the bottom right corner of the screen. I noticed when you mess with the viewport rect it somewhat scales evenly. So if I change the resolution of my screen it will change the resolution of the camera... Which is what I don't want. I want it to be constant, not changing. Just showing the movement of my objects but without changing the camera size.