TY - JOUR
T1 - Investigation of structural and electronic properties of doped ceria Ce1-xMxO2 (M=Hf,Ti,Ba,Mg,Nb,Vx=0.25%) for ReRAM applications
T2 - A first principles study
AU - Khera, Ejaz Ahmad
AU - Ullah, Hafeez
AU - Hussain, Fayyaz
AU - Imran, Muhammad
AU - Khalil, R. M.Arif
AU - Sattar, M. Atif
AU - Rana, Anwar Manzoor
AU - Mahata, Chandreswar
AU - Kim, Sungjun
N1 - Publisher Copyright:
© 2020
PY - 2020/5
Y1 - 2020/5
N2 - Since last few decades, in-spite of much progress in oxide-based resistive random access memory (ReRAM) devices, there are many challenges to the era of science and technology, particularly information and rupture of the conducting filament and device uniformity related concerns. The first principles calculations based on density functional theory (DFT) were made to investigate structural and electronic properties of doped ceria (CeO2), i.e., Ce1-xMxO2 (M = Hf, Ti, Ba, Mg, V, Nb x = 0.25%) with and without oxygen vacancy (Vo) for ReRAM devices wherein six dopants having different electronic configuration and radii are used. Effect of isovalent, low-valent (p-type) and high-valent (n-type) dopants was observed using the Perdew, Burke and Ernzerhof and generalized gradient approximation (PBE-GGA) approach. The present study also elaborates the role of oxygen vacancy in formation and rupture of conducting filaments (Cfs). The tendency towards reduction of oxygen vacancy formation energies to improve device performance has been observed for all dopants and found consistent with available data. We explored that the dopants impact oxygen vacancy formation energies locally and increase the clustering of Vo near dopants as a results conductivity has been increased. Structural investigation unveiled that in all cases, volume of the crystal lattice increases with dispense of the band gap energies which lead to enhance conductivity. TDOS and PDOS results show that energy states are shifted towards lower energy region due to dopant and/or oxygen vacancy. The oxygen vacancy in the lattice causes the formation of defect assisted conducting channels in the resistive switching devices.
AB - Since last few decades, in-spite of much progress in oxide-based resistive random access memory (ReRAM) devices, there are many challenges to the era of science and technology, particularly information and rupture of the conducting filament and device uniformity related concerns. The first principles calculations based on density functional theory (DFT) were made to investigate structural and electronic properties of doped ceria (CeO2), i.e., Ce1-xMxO2 (M = Hf, Ti, Ba, Mg, V, Nb x = 0.25%) with and without oxygen vacancy (Vo) for ReRAM devices wherein six dopants having different electronic configuration and radii are used. Effect of isovalent, low-valent (p-type) and high-valent (n-type) dopants was observed using the Perdew, Burke and Ernzerhof and generalized gradient approximation (PBE-GGA) approach. The present study also elaborates the role of oxygen vacancy in formation and rupture of conducting filaments (Cfs). The tendency towards reduction of oxygen vacancy formation energies to improve device performance has been observed for all dopants and found consistent with available data. We explored that the dopants impact oxygen vacancy formation energies locally and increase the clustering of Vo near dopants as a results conductivity has been increased. Structural investigation unveiled that in all cases, volume of the crystal lattice increases with dispense of the band gap energies which lead to enhance conductivity. TDOS and PDOS results show that energy states are shifted towards lower energy region due to dopant and/or oxygen vacancy. The oxygen vacancy in the lattice causes the formation of defect assisted conducting channels in the resistive switching devices.
KW - Conducting filaments
KW - Formation energy
KW - Oxygen vacancy
KW - ReRAM
KW - Uniformity
UR - http://www.scopus.com/inward/record.url?scp=85080035620&partnerID=8YFLogxK
U2 - 10.1016/j.physe.2020.114025
DO - 10.1016/j.physe.2020.114025
M3 - Article
AN - SCOPUS:85080035620
SN - 1386-9477
VL - 119
JO - Physica E: Low-Dimensional Systems and Nanostructures
JF - Physica E: Low-Dimensional Systems and Nanostructures
M1 - 114025
ER -