Nowadays, there is an increasing interest in the study of magnetic multilayers with very thin oxide layers for applications such as spintronics and magnetic / magneto-optical recording. In this work we present a simple method to fabricate high quality multilayers with the use of a single magnetron sputtering head operating in ultrahigh vacuum (5x10-8 mbar). Namely, at the end of the deposition of each single Ni or Co layer, air is let into the chamber through a fine leak valve. Then a very thin NiO or CoO layer (~ 1.5 nm) is formed by natural oxidation. The process is repeated and the result is the formation of multilayers with excellent layering. Here we will review the structural and magnetic properties. The Ni/NiO multilayers show positive interface anisotropy and tendency for perpendicular magnetic anisotropy, while, for the Co/CoO ones, inverted hysteresis loops are recorded.