Because of the benefits of low power and high speed, binary oxide based resistive memory (RRAM) is considered the potential candidate of the next generation nonvolatile memory [1,2]. To be implemented in the future technology node, the scalability of memory device down to nanoscale is an important criterion for RRAM technology development. Through the integration with concave structure, it has been demonstrated that, even in nanoscale, the HfO2 based resistive memory with a Ti reactive layer still exhibited bipolar resistance switch (RS) characteristics [3]. However, the large parasitic capacitance from the parallel capacitor consisting of TiN/Ti/HfO2/SiO2/TiN in the concave structure degrades the memory performance [3]. Besides, the complexity of process for the concave structure, which needs an additional process to fabricate a SiO2 supporting layer, makes it less attractive to IC industry.