Writing fragment shader data to RenderTexture

I have a shader that computes complex functions to generate a height map. When I apply this shader to a material and then to a plane, the height map displays correctly.

Now, I need to access the height map's data in scripts, which I think can only be done with a RenderTexture (correct me if I'm wrong). I saw multiple tutorials to render the camera's view to a RenderTexture but I can't quite find a solution.

Any help would be greatly appreciated.