The refractory transition metal nitride (TMN) film Hafnium nitride (HfNx) was successfully prepared on silicon-based substrates as bottom electrodes for resistive random access memory (RRAM) cells in Pt (top)/metal oxide/ HfNx (bottom) sandwich structure. The reproducible resistive switching (RS) characteristics of the memory cells were studied systematically for RRAM applications. The advantages of adopting HfNx instead of Pt as bottom electrode material were demonstrated, including the improvement of the low resistive state value, the RS endurance and the uniformity of RS parameters. The composition and chemical bonding states of the prepared HfNx was analyzed by X-ray photoelectron spectroscopy(XPS) technique. The nitrogen content in the HfNx and the Gibbs free energy of the corresponding metal oxide formation has great influences on the RS properties. The oxygen reservoir ability and diffusion barrier effect of the HfNx play a key role in the RS performance improvement of the RRAM devices.
Received 09 December 2012Accepted 14 February 2013Published online 01 March 2013
This work was supported by the National High Technology Development Program of China (2008AA031402), Foundation Project by Science and Technology Council of Shanghai (Grant No. 1052nm07200).
Article outline: I. INTRODUCTION II. EXPERIMENT A. Device fabrication B. Physical characterization III. RESULTS AND DISCUSSION A. Resistive switching and Non-volatile Memory characteristics B. XPS characterization results C. The key factor for performance improvement and model for RS mechanism IV. CONCLUSION
Using static stores, e.g. storage tubes, semiconductor memories
Qigang Zhou and
Source:AIP Advances 3, 032102 (
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