Electrical conduction mechanisms of metal∕La2O3∕Si structure

Abstract

Metal-oxide-semiconductor capacitors that incorporate La2O3 dielectric films were deposited by radio frequency magnetron sputtering. In this work, the essential structures and electrical properties of La2O3 thin films were investigated. Capacitance–voltage, energy dispersive x-ray spectrometry, and transmission electron microscopy analyses reveal that an interfacial layer was formed, subsequently reducing the effective dielectric constant of the 700°C annealed La2O3 thin films. The dominant conduction mechanism of the Al∕La2O3∕p-Si metal-lanthanum oxide-semiconductor capacitor is space-charge-limited current from 300to465K in the accumulation mode. Three different regions, Ohm’s law region, trap-filled-limited region, and Child’s law region, were observed in the current-density–voltage (J–V) characteristics at room temperature. The activation energy of traps calculated from the Arrhenius plots was about 0.21±0.01eV. The electronic mobility, trap density, dielectric relaxation time, and density of states in the conduction band were determined from the space-charge-limited conduction at room temperature.

Modulation of charge trapping and current-conduction mechanism of TiO2-doped HfO2 gate dielectrics based MOS capacitors by annealing temperature

“…This type of low field current conduction may be due to a hopping mechanism where current is carried by thermally excited electrons moving between isolated discrete defect states [31]. According to the Lampert's theory of space charge limited mechanism, the Ohm's conduction dominates at low gate bias which can be mathematically described as follows [32]: (13) where J Ohm is the current density, q is electronic charge, n o is concentration of free-charge carrier in thermal equilibrium, m is electronic mobility in the oxide and t ox is physical thickness of the oxide. Fig.…”

Experimental determination of La2O3 thermal conductivity and its application to the thermal analysis of a-Ge/La2O3/c-Si laser annealing

“…[2,[7][8][9]. More works report on the mechanisms of the electrical and thermal conduction, the study of the crystallographic properties, thermomechanical processing [10][11][12][13][14][15] or even a thermodynamic description of La 2 O 3 -Y 2 O 3 system [16].…”

Coexistence of analog and digital resistive switching in BiFeO3-based memristive devices

“…Under the negative voltage bias shown in Fig. 4(a), the transport follows the Ohm's law (slope~1) in the low bias region at the HRS, implying that the density of thermally generated free carriers is larger than the injected carriers [35,36]. When the applied voltage bias exceeds the transition voltage V tr at about − 0.7 V, a slope of~2 arises, which suggests that the conduction enters the trap-filled-limited region, the traps are filled and a space charge appears.…”