In this paper, RuRhMn-based and PtMn-based spin valves with magnetic oxide layer (MOL) inserted in the free layer, pinned layer, or both lavers were studied. Both magnetoresistance (MR) ratio and DeltaR(sq) were increased in these spin valves, due to the insertion of MOL, Theoretical calculation based on semi-classical Boltzmann equation for transport indicated that the enhancement of MR ratio can be attributed to the strong specular scattering at interface with MOL. PtMn specular spin valves are more thermally stable than RuRhMn spin valves, Their thermal stability can de further improved by using a synthetic pinned layer with MOL, where the effective exchange field degrades less than 20% when the temperature is increased up to 350 degreesC.