Abstract
Resistive random access memory (RRAM) is one of the most promising new generation memory device candidates. In our research, we applied ZrTiOx (ZTO) thin film in metal/insulator/semiconductor (MIS) and metal/insulator/metal (MIM) structured RRAM. cells with a thin oxygen-deficient ZrTiOx film and try to make devices show good properties. As our experiment results, we found that ZrTiOx based RRAM devices show different properties with different device structures and production process. For example, devices with structure Ni/ZTO/n+ Ge demonstrate a unipolar switching behavior and with structure Pt/Ti/ZTO/n+ Si demonstrate a bipolar switching behavior. MIS RRAM devices with Pt/Ti/ZTO/n+ Ge structure demonstrate a stable bipolar switching behavior, and show small operation voltage (SET V:2.4V, RESET V:-2.05 V), fast operation speed (500 ns), good R/S ratio(104), Endurance(104 times), and data retention(105 sec, @85oC). MIM RRAM with Pt/Ti/ZTO/Pt structure also show small operation voltage (SET V:0.47V, RESET V:-0.73 V), fast operation speed (100 ns), good R/S ratio(86x), Endurance(104 times), and data retention(105 sec, @RT). Both devices show promising properties as nonvolatile memory devices. To understand the resistance switching phenomenon of devices, we observe the I-V curves of devices, and believe that the switching phenomenon induced by filament theory.