Carrier transport mechanisms in the ZnO based heterojunctions grown by MBE

Structural Properties and Electrical Characteristics of p-n Junctions Based on Kesterite Cu2ZnSnS4 Layers for Thin-Film Solar Cells

“…Region I includes voltages of up to ~0.2 V. In Region II, the plot is non-linear and can be approximated by function I ∼ e A•V , where A is a constant. This behavior is observed for voltage bias lower than 1 V. It is characteristic for multitunneling capture-emission (MTCE) currents [27]. For higher voltage bias, the linearity of the curve is observed once again (Region III and IV) but this time the slope totals more than two for each sample.…”

“…The p-n junction can be described with a model that assumes occurrence of diffusion or generation-recombination currents. The ideality factor is then in the range of 1 < n ≤ 2 [27]. When n > 2, the charge transport is governed by different current mechanisms, such as the inhomogeneous distribution of recombination centers [28], shunt resistance effects [29], nonlinear metalsemiconductor contacts [30], tunneling currents, and carrier trapping by the surface states or impurities [27,31].…”

“…The ideality factor is then in the range of 1 < 𝑛 ≤ 2 [27]. When 𝑛 > 2, the charge transport is governed by different current mechanisms, such as the inhomogeneous distribution of recombination centers [28], shunt resistance effects [29], nonlinear metal-semiconductor contacts [30], tunneling currents, and carrier trapping by the surface states or impurities [27,31]. Therefore, it was decided to take a closer look at current transport mechanisms in the junctions by analyzing forward bias I-V curves in double logarithmic scale, as shown in Figure 8.…”

Analysis of Current Transport Mechanism in AP-MOVPE Grown GaAsN p-i-n Solar Cell

“…This paper's aim is to investigate the electro-optical and structural properties of a p-i-n solar cell with a GaAsN base and correlate them with the dominant mechanism that is responsible for carrier transport. In general, electrical transport through p-n or p-i-n junction is governed by various physical phenomena such as diffusion, recombination, thermionic field emission or tunnelling [38][39][40][41][42][43][44]. Temperature-dependent current-voltage (J-V-T) measurements were used to determine the main conduction mechanism in a GaAsN solar cell and estimate potential generation-recombination centers.…”

“…Here, we focused only on the dark J-V-T characteristics measured in the range 100-380 K with 20 K step, which are depicted in Figure 7. Generally, current transport through the p-n or p-i-n junction is governed by various physical phenomena such as diffusion, recombination, thermionic field emission or tunnelling [38][39][40][41][42][43][44]. Precise analysis of temperature-dependent J-V characteristics allows for identification of the dominant mechanism responsible for charge carrier transport.…”