On conditions leading to crossing of I–V curve in metal1|mixed-ionic–electronic-conductor|metal2 devices

Enhancing the memory window of AZO/ZnO/ITO transparent resistive switching devices by modulating the oxygen vacancy concentration of the top electrode

“…An asymmetric I-V curve of the 12AZO device may have occurred because of the modification of the Schottky barrier height at each interface as a result of the differences in the work function between the top and bottom electrodes [38]. A series of I-V sweep tests were conducted to determine whether the work function of electrodes was responsible for the asymmetric behavior and also the existence of the Schottky barrier at the bottom electrode.…”

Dynamic Current–Voltage Analysis of Oxygen Vacancy Mobility in Praseodymium‐Doped Ceria over Wide Temperature Limits

“…In the following, we provide a short review of the dynamic I – V analysis method and the assumptions made in its application. In general, the I–V relations (where the applied voltage, for instance, is a periodic triangular waveform) of a thin mixed ionic–electronic conductor placed between two ion blocking and electronically conducting electrodes are nonlinear if an applied voltage has a sufficiently high amplitude and low frequency . In that case, the I–V curve has a characteristic hysteretic shape, exhibiting a peak current followed by a region with a dynamic negative differential resistance (e.g., see Figure b).…”

“…For an MIEC with a prevailing electronic conductivity, a typical situation for a reduced oxide at low temperatures, the local depletion in oxygen vacancies leads to an increase in total resistance. This phenomenon was previously modeled in detail by solving the electrically coupled ion and electron transport equations . It was further demonstrated that the characteristic physical time constant of the MIEC, the oxygen vacancy drift time through the MIEC length, can be determined from the time at which the peak current is reached, t peak (time‐to‐peak parameter), for a given voltage sweep rate, a SR , of a periodic triangular waveform .…”

“…In general, the I-V relations (where the applied voltage, for instance, is a periodic triangular waveform) of a thin mixed ionic-electronic conductor placed between two ion blocking and electronically conducting electrodes are nonlinear if an applied voltage has a sufficiently high amplitude and low frequency. [24,30] In that case, the I-V curve has a characteristic hysteretic shape, exhibiting a peak current followed by a region with a dynamic negative differential resistance (e.g., see Figure 3b). The hysteretic shape and peak current occur due to resistance changes induced by the drift and redistribution of the positively charged oxygen vacancies, and in turn, the electronic species, driven by the applied electrical field.…”

“…This phenomenon was previously modeled in detail by solving the electrically coupled ion and electron transport equations. [30] It was further demonstrated that the characteristic physical time constant of the MIEC, the oxygen vacancy drift time through the MIEC length, can be determined from the time at which the peak current is reached, t peak (time-to-peak parameter), for a given voltage sweep rate, a SR , of a periodic triangular waveform. [23] The latter relationship is described by Equation (1) that provides a practical means of extracting the ionic defect mobility, e.g., of oxygen vacancies, in the MIEC from the experimentally obtained t peak (measured relative to time at which the applied voltage crosses zero)…”