The present disclosure provides a semiconductor structure. The semiconductor structure includes a substrate, a transistor region, a metal interconnect, and a magnetic tunneling junction (MTJ). The transistor region includes a gate over the substrate, and a doped region is at least partially in the substrate. The metal interconnect is over the doped region. The metal interconnect includes a metal via. The MTJ is entirely underneath the metal interconnect and between the doped region and the metal via, and a diameter of a bottom surface of the MTJ is greater than a diameter of an upper surface of the MTJ.