This paper explores a novel design of an encapsulated and integrated device, which employs an oscillatory fluid flow to cool micro spots in micro systems. The oscillatory flow can be induced by two thermal bubbles that form and expand in turn on two micro line heaters at both ends of a sealed fluid channel. Compared with those using outside connecting channels and pumps, this design benefits from its much smaller size. A numerical calculation indicates that the heat transfer enhancement is independent of the Wormersely number, but depends on the Peclet number, Pe, and the cooling capacity of channel walls. The heat transfer rate increases dramatically as Pe increases from 30 to 100.