How to subdivide on a new face - doesn't work

I have a hole in my object. the vertices surrounding the square hole are aligned on x-axis. I want to add a surface/face by selecting all vertices and pressing ‘f’. it adds a face. than i want to subdivide it like the rest of the surface of the object, but it doesn’t. instead it pulls the centres of adjoining planes towards the new plane.http://gifti.me/i/O5NmhM.gif

Subdivide creates edge loops across quads. You have a big fat n-gon there. Subdivide is not the correct method. You should use grid fill to fill that hole, not F.