Studies on ReRAM Conduction Mechanism and the Varying-bias Read Scheme for MLC and Wide Temperature Range TMO ReRAM

The resistance of transition metal oxide (TMO) ReRAM is a strong function of temperature which resulting in the variation of the memory window and limiting the applications in wide-temperature range or multi-level data storage. This paper investigates the device conduction mechanism and suggests a model to correlate the cell resistance with temperature and the bias condition. The testing results from the 1Mb WOx ReRAM array agree with the model very well. A read scheme that varies the read bias based on the device temperature as well as target sensing level is discussed here. A large and constant memory window is preserved for MLC across a wide temperature range (-40°C to 125°C), suitable for high-reliability applications.