Capacitance methodology for investigating defect states in energy gap of organic semiconductor

Crystallization driven boost in fill factor and stability in additive-free organic solar cells

“… 34 In this case, N A accounts for the shallow level acceptors, which are ionized in the space-charge region and they are correlated with the density of defects. 35 The dielectric constant ε r considered for the calculation was extracted from the high negative bias limit for each condition using ε r = Cd / ε 0 A , where d is the layer thickness. As shown in Table S1, † the SVA devices exhibited a V BI of around 10% lower than that for the other three conditions.…”

“…where is the build in potential, the relative permittivity or dielectric constant, the 𝑉 𝐵𝐼 𝜀 𝑟 𝜀 𝑜 permittivity of vacuum, q is the elementary charge, A the area of the junction and the 𝑁 𝐴 concentration of mobile charges 34 . In this case, accounts to the shallow level acceptors, 𝑁 𝐴 which are ionized in the space-charge region and they are correlated with the density of defects 35 . The dielectric constant considered for the calculation was extracted from the high 𝜀 𝑟 negative bias limit for each condition using = Cd/ A, where d is the layer thickness.…”

Characterization of Strain-induced Defects Density in Flexible Organic Photovoltaic Cells using Capacitance Spectroscopy

“…These newly formed defects are the result of structural disorders and layers detachment during the strain process which reduce the polymer's conductivity and the device performance by capturing the charge carriers. Further study can be done using the techniques such as point-to-point C-V and drive level capacitance profiling to obtain the spatial distribution of trap states [45]. The density of defect states at layer interfaces, in the bulk and near cracks will reveal the major trap locations developed in the strained OPV.…”

A New Benchmark of Charges Storage in Single-Layer Organic Light-Emitting Diodes Based on Electrical and Optical Characteristics

“…By superposing tiny alternating stress to driving bias, Impedance spectroscopy (IS) or capacitance-voltage (C-V) characteristics can detect the response of excess charges and reveal the mechanism. Based on it, the defect states or carrier motion have been analyzed [ 30 , 31 , 32 ]. In addition, photo-capacitance has also attracted more attention [ 33 , 34 , 35 ].…”