The invention relates to implantable medical devices, particularly, to porous structures for such devices. In one aspect, the invention provides a porous metal scaffold comprising a porous metal network having pores defined by metal webs, the metal webs covered with at least one layer of metal particles bonded to the metal webs. In other aspects, the invention provides methods of forming porous scaffolds. In one such aspect, the method includes providing a polymer foam； forming a skin of biocompatible metal on the polymer foam by low temperature arc vapor deposition； and heating the polymer foam and' the metal skin above the decomposition temperature of the polymer foam in an inert gas atmosphere； thereby the polymer foam decomposes producing a green metal foam. In yet other aspects, the invention provides methods of improving stability of porous scaffolds.
