TY - JOUR

T1 - Capacitance voltage curve simulations for different passivation parameters of dielectric layers on silicon

AU - Sevillano-Bendezú, M. A.

AU - Dulanto, J. A.

AU - Conde, L. A.

AU - Grieseler, R.

AU - Guerra, J. A.

AU - Töfflinger, J. A.

N1 - Publisher Copyright:
© Published under licence by IOP Publishing Ltd.

PY - 2020/1/13

Y1 - 2020/1/13

N2 - Surface passivation is a widely used technique to reduce the recombination losses at the semiconductor surface. The passivating layer performance can be mainly characterized by two parameters: The fixed charge density (Q ox) and the interface trap density (D it) which can be extracted from Capacitance-Voltage measurements (CV). In this paper, simulations of High-Frequency Capacitance-Voltage (HF-CV) curves were developed using simulated passivation parameters in order to examine the reliability of measured results. The D it was modelled by two different sets of functions: First, the sum of Gaussian functions representing different dangling bond types and exponential tails for strained bonds. Second, a simpler U-shape model represented by the sum of exponential tails and a constant value function was employed. These simulations were validated using experimental measurements of a reference sample based on silicon dioxide on crystalline silicon (SiO2/c-Si). Additionally, a fitting process of HF-CV curves was proposed using the simple U-shape D it model. A relative error of less than 0.4% was found comparing the average values between the approximated and the experimentally extracted D it's. The constant function of the approximated D it represents an average of the experimentally extracted D it for values around the midgap energy where the recombination efficiency is highest.

AB - Surface passivation is a widely used technique to reduce the recombination losses at the semiconductor surface. The passivating layer performance can be mainly characterized by two parameters: The fixed charge density (Q ox) and the interface trap density (D it) which can be extracted from Capacitance-Voltage measurements (CV). In this paper, simulations of High-Frequency Capacitance-Voltage (HF-CV) curves were developed using simulated passivation parameters in order to examine the reliability of measured results. The D it was modelled by two different sets of functions: First, the sum of Gaussian functions representing different dangling bond types and exponential tails for strained bonds. Second, a simpler U-shape model represented by the sum of exponential tails and a constant value function was employed. These simulations were validated using experimental measurements of a reference sample based on silicon dioxide on crystalline silicon (SiO2/c-Si). Additionally, a fitting process of HF-CV curves was proposed using the simple U-shape D it model. A relative error of less than 0.4% was found comparing the average values between the approximated and the experimentally extracted D it's. The constant function of the approximated D it represents an average of the experimentally extracted D it for values around the midgap energy where the recombination efficiency is highest.

UR - http://www.scopus.com/inward/record.url?scp=85079011014&partnerID=8YFLogxK

U2 - 10.1088/1742-6596/1433/1/012007

DO - 10.1088/1742-6596/1433/1/012007

M3 - Conference article

AN - SCOPUS:85079011014

SN - 1742-6588

VL - 1433

JO - Journal of Physics: Conference Series

JF - Journal of Physics: Conference Series

IS - 1

M1 - 012007

T2 - Peruvian Workshop on Solar Energy 2019, JOPES 2019

Y2 - 8 May 2019 through 10 May 2019

ER -