Effects of heat dissipation on unipolar resistance switching in Pt∕NiO∕Pt capacitors

We fabricated Pt∕NiO∕Pt capacitor structures with various bottom electrode thicknesses tBE and investigated their resistance switching behaviors. The capacitors with tBE⩾50nm exhibited typical unipolar resistance memory switching, while those with tBE⩽30nm showed threshold switching. This interesting phenomenon can be explained in terms of the temperature-dependent stability of conducting filaments. In particular, the thinner tBE makes dissipation of Joule heat less efficient, so the filaments will be at a higher temperature and become less stable. This study demonstrates the importance of heat dissipation in resistance random access memory.