TY - JOUR
T1 - Stabilized and RESET-voltage controlled multi-level switching characteristics in ZrO2-based memristors by inserting a-ZTO interface layer
AU - Ismail, Muhammad
AU - Abbas, Haider
AU - Choi, Changhwan
AU - Kim, Sungjun
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/9/15
Y1 - 2020/9/15
N2 - Transition metal oxides based memristors possess multi-resistance states and can be used as a main source for memory devices. However, variability in resistive switching (RS) characteristics is a major issue for the application of memristor devices in emerging information computing system. The achievement of stable switching between high resistance state (HRS) and low resistance states (LRS) has become an important task for their implementation and industrial production. In this study, issues of oxygen accumulation and variations in the HRS of single layer (SL) Ta/ZrO2/TiN memristor devices, stability of HRS and concentrated distribution of SET-voltages were realized by inserting a thin amorphous zinc-tin-oxide (a-ZTO) film between the TiN bottom electrode and ZrO2 RS layer. With this bilayer (BL) Ta/ZrO2/a-ZTO/TiN memristor device, stabilized RS properties, such as ON/OFF ratio >102, smaller forming voltages, uniform SET-/RESET-voltages, and good pulse switching endurance (>105 cycles) have been demonstrated as compared to SL memristor devices. In addition, BL memristor device also exhibited four distinct resistance levels (three high resistance levels with same LRS) by adjusting RESET-stop voltages, and each level showed multilevel endurance and reliable retention characteristics. The current transport mechanism has been investigated at HRS of different RESET-stop voltages (i.e. 1.5 V, 1.7 V and 1.9 V), which confirms that Schottky barrier height increases by increasing the RESET-voltages. Finally, a conducting model was proposed to illuminate the effect of a-ZTO thin layer and to explain the physical mechanism of stabilized RS behavior.
AB - Transition metal oxides based memristors possess multi-resistance states and can be used as a main source for memory devices. However, variability in resistive switching (RS) characteristics is a major issue for the application of memristor devices in emerging information computing system. The achievement of stable switching between high resistance state (HRS) and low resistance states (LRS) has become an important task for their implementation and industrial production. In this study, issues of oxygen accumulation and variations in the HRS of single layer (SL) Ta/ZrO2/TiN memristor devices, stability of HRS and concentrated distribution of SET-voltages were realized by inserting a thin amorphous zinc-tin-oxide (a-ZTO) film between the TiN bottom electrode and ZrO2 RS layer. With this bilayer (BL) Ta/ZrO2/a-ZTO/TiN memristor device, stabilized RS properties, such as ON/OFF ratio >102, smaller forming voltages, uniform SET-/RESET-voltages, and good pulse switching endurance (>105 cycles) have been demonstrated as compared to SL memristor devices. In addition, BL memristor device also exhibited four distinct resistance levels (three high resistance levels with same LRS) by adjusting RESET-stop voltages, and each level showed multilevel endurance and reliable retention characteristics. The current transport mechanism has been investigated at HRS of different RESET-stop voltages (i.e. 1.5 V, 1.7 V and 1.9 V), which confirms that Schottky barrier height increases by increasing the RESET-voltages. Finally, a conducting model was proposed to illuminate the effect of a-ZTO thin layer and to explain the physical mechanism of stabilized RS behavior.
KW - Amorphous-ZTO layer
KW - Improved endurance performance
KW - Multilevel resistive switching
KW - Schottky barrier effect
KW - ZrO thin film
UR - http://www.scopus.com/inward/record.url?scp=85083884279&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2020.155256
DO - 10.1016/j.jallcom.2020.155256
M3 - Article
AN - SCOPUS:85083884279
SN - 0925-8388
VL - 835
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
M1 - 155256
ER -