Influence of a 3D electric field enhancement model on the Monte Carlo calculation of the dark current in pixel arrays

Abstract

A new three-dimensional electric field enhanced generation model has been developed to describe the electric field effects on the thermal electron-hole pair generation rate. The originality of this model lies on the full threedimensional description of the synergetic mechanism between the Poole-Frenkel barrier lowering and the Phonon-Assisted Tunneling mechanism. To do this, a classical 1D model has been integrated over all possible directions of emission of the carriers. The 3D model has been implemented in a Monte Carlo tool devoted to the simulation of the dark current increase induced by radiations in image sensors. Our three-dimensional simulation has been compared to one-dimensional electric field effects simulations and experimental data found in the literature in the context of gold contamination. The consequence of using a three-dimensional electric field enhanced generation (EFEG) model is the reduction of the dispersive effect on the dark current distribution of the electric field: hence each dark current peak is narrower and shows higher peak's amplitude. The threedimensional model needs to slightly change the cross section parameters used for a 1D EFEG case to keep a realistic description of each dark current peak of the histogram. In the rest of the paper, we extended our work on constraints relative to space applications. The histograms of the simulated dark current taking into account one and three dimensional electric field enhancement effects have been estimated and compared to experimental data acquired after a proton irradiation at room temperature. The use of a three-dimensional model tends to give a more realistic prediction of the dark current non uniformity in an irradiated pixel array.

A Kinetic Monte Carlo Algorithm to Model the Annealing Process and Compute the Dark Current Nonuniformity

“…However, the selected values remain within the range of effective sections encountered in the literature (see references in section IV.C). The choice of hole capture cross section (instead of the electron one) is supported by the fact the thermal generation rate is more sensitive to the variation of hole capture cross section for an acceptor trap level when electric field enhancement effects are considered, as explained in [50]. Considering these adjusted parameters leads to a better estimation of the whole dark current distribution, as shown on Fig.…”

“…In addition, a 3D Electric Field Enhancement (3D EFE) effects model is used to simulate the influence of the electric field on the electron-hole pair thermal generation rate [50]. For a nuclear reaction , the dark current associated is computed as follows:…”

“…4, the comparison between simulations using the KMC method and those using the universal damage factor shows that, for the simulation parameters considered, results are quite equivalent. The method used to take into account the 3D EFE model with the UDF is the same as the reference [50]. For proton modeling of 6.5 MeV (trap population and annealing factor corresponding to 1 keV PKA), the simulation from the KMC method provided a very slight overestimation of the maximum dark current (about a factor 1.1) compared to the universal damage factor method.…”

Monte-Carlo simulation and experimental study of the effect of internal charging on the electron emission yield of amorphous SiO2 thin films

“…The final emission rate for the deep coulombic trap can be written by including both PAT and PF enhancements [53]:…”

Statistical spread on the displacement damage degradation of irradiated semiconductors

“…Dark current distribution can be estimated simply assuming proportionality between the dark current and the number of atomic displacements [51][52][53][54][55][56]. Thermal emission rate of defects can also be modelled in an improved version that also takes into account electric field enhancement effect [66]. But here, one just needs to calculate the initial damage distribution.…”