Best Nikon pan cake lens?

Basically i've got a nikon d90 and d3100.
Wanted a pancake lens which clicks top quality photos.
Price within 1000$… And don't give names of other than
pancake lens

Nikon does not make pancake lenses for DSLR cameras.

Nikon has not done much in pancakes the last 30 years or so. The only one that comes to mind is the 45mm f2.8 Ai-p. Bit of an oddball that in being the only Ai-P lens. It's manual focus but it does contain a chip so you can control aperture via the camera.
Production was stopped a few years ago but you should be able to find a near-mint copy for the price you have in mind. Herés a review: http://www.photozone.de/...rt?start=1

Voigtlander has also dabbled with pancakes, a 20mm and 40mm come to mind. Also Ai-P compatible. Little reports I've read seem positive but the supply of these is a nightmare, difficult to find outside of Asia.