%0 Journal Article
%A Kim, W.
%A Menzel, S.
%A Wouters, D. J.
%A Waser, R.
%A Rana, V.
%T 3-Bit Multilevel Switching by Deep Reset Phenomenon in Pt/W/TaO$_{X}$ /Pt-ReRAM Devices
%J IEEE electron device letters
%V 37
%N 5
%@ 1558-0563
%C New York, NY
%I IEEE
%M FZJ-2016-07037
%P 564 - 567
%D 2016
%X The influence of two different ohmic electrodes (W and Ta) on the resistive switching characteristics of TaOx-based resistive random access memory (ReRAM) devices has been studied. Consistently, higher resistance OFF states have been observed with the W-ohmic electrode under the same operational conditions for all reset stop voltages (Vreset-stop) during both the dc and ac measurements. The deeper reset for samples with W-electrode is attributed to the less negative Gibbs-free energy of W-oxide compared with Ta-oxide, resulting in easier re-oxidation of the filament through oxygen exchange with the W-electrode. The higher ROFF/RON(>103) with the W-electrode enables 3-bit multilevel cell operation in the Pt/W/TaOx/Pt ReRAM device. An excellent retention for these eight states is demonstrated at 125°C for 104 s. Furthermore, the TaOx ReRAM device with both the electrodes shows high endurance up to 106 cycles based on two states.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000374868300010
%R 10.1109/LED.2016.2542879
%U https://juser.fz-juelich.de/record/824448