Perovskite solar cells (PSCs) have drawn significant consideration as a competing solar cell technology because of the drastic advance in their power conversion efficiency (PCE) over the last two decades. The interfaces between the electron transport layer (ETL) and the absorber layer and between the absorber layer and the hole transport layer (HTL) have a major impact on the performance of the PSCs. In this paper, we have investigated the defect interfaces between ETL/absorber layer and absorber layer/HTL of calibrated experimental CH ₃ NH ₃ PbX ₃ lead-based and FASnI ₃ lead-free PSCs. The influence of the defect interfaces is studied in order to find the optimum value for the maximum possible PCE. While the PCE has not been enhanced considerably for the lead-based, it is boosted from 1.76% to 5.35% for lead-free PSCs. Also, bulk traps were found to have minor role in comparison with interface traps for the lead-free cell while they have a significant impact for the lead-based cell. The results presented in this work would shed some light on designing interface defects of various types of practical PSC structures and demonstrates the crucial impact of the interface defects on lead-free vs lead-based PSCs. All simulation studies are performed by using SCAPS-1D simulator.

Perovskite solar cells (PSCs) have attracted considerable attention as a competitor technology in solar cells due to the rapid enhancement in their power conversion efficiency (PCE) in recent years. PSCs have several advantages such as their bandgap tunability, lower cost, tolerance of high impurities, protracted diffusion length and wide optical absorption. In this paper, simulation of PSCs with copper oxide as a hole transport material (HTM) and different electron transport materials (ETMs) has been presented. The proposed materials are a replacement to the ordinary hole and ETMs; such as the titanium dioxide and the expensive spiro-OMeTAD. In addition, a comprehensive study for optimizing the features and parameters of the PSCs, such as the thickness and defect density of the perovskite layer, the doping concentrations, and the bandgap energy, has been introduced. The simulation and the performance evaluation of the designed PSCs have been carried out using SCAPS-1D. The results show that mixed halide PSC with zinc oxysulfide as ETM and copper oxide as HTM has an enhanced performance with a PCE of up to 30.82%.

In this paper, the effect of a proposed drain doping engineering on the ambipolar conduction and high-frequency performance of tunneling FETs (TFETs) is investigated using 2-D TCAD simulations. The proposed TFET structure is based on using a high-doped region above a low-doped region of the drain side. It is demonstrated that when splitting the drain into two regions, one with high doping above the other of low doping, the tunneling width at the channel-drain interface increases. This increase in the tunneling width causes an appreciable reduction of ambipolar current in the TFET. Moreover, high-frequency figures of merit regarding the transconductance (gm), source-to-gate and drain-to-gate capacitances, and unit-gain cutoff frequency (fT) are analyzed. It is found that the combination of drain doping regions could enhance the high-frequency performance. Additionally, the proposed technique does not deteriorate the ON-current levels.