Two dimensional numerical simulations of carrier dynamics during time-resolved photoluminescence decays in two-photon microscopy measurements in semiconductors

We use two-dimensional numerical simulations to analyze high spatial resolution time-resolved spectroscopy data. This analysis is applied to two-photon excitation time-resolved photoluminescence (2PE-TRPL) but is broadly applicable to all microscopic time-resolved techniques. By solving time-dependent drift-diffusion equations, we gain insight into carrier dynamics and transport characteristics. Accurate understanding of measurement results establishes the limits and potential of the measurement and enhances its value as a characterization method. Diffusion of carriers outside of the collection volume can have a significant impact on the measured decay but can also provide an estimate of carrier mobility as well as lifetime. In addition to material parameters, the experimental conditions, such as spot size and injection level, can impact the measurement results. Although small spot size provides better resolution, it also increases the impact of diffusion on the decay; if the spot size is much smaller than the diffusion length, it impacts the entire decay. By reproducing experimental 2PE-TRPL decays, the simulations determine the bulk carrier lifetime from the data. The analysis is applied to single-crystal and heteroepitaxial CdTe, material important for solar cells, but it is also applicable to other semiconductors where carrier diffusion from the excitation volume could affect experimental measurements.

[1]  J. Squier,et al.  Development of Two-photon excitation time-resolved photoluminescence microscopy for lifetime and defect imaging in thin film photovoltaic materials and devices , 2015, 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC).

[2]  Darius Kuciauskas,et al.  The role of drift, diffusion, and recombination in time‐resolved photoluminescence of CdTe solar cells determined through numerical simulation , 2014 .

[3]  Shujuan Huang,et al.  Morphology and Carrier Extraction Study of Organic-Inorganic Metal Halide Perovskite by One- and Two-Photon Fluorescence Microscopy. , 2014, The journal of physical chemistry letters.

[4]  R. Scheer,et al.  Theoretical study of time-resolved luminescence in semiconductors. II. Pulsed excitation , 2014 .

[5]  R. Scheer,et al.  Theoretical study of time-resolved luminescence in semiconductors. I. Decay from the steady state , 2014 .

[6]  D. Levi,et al.  Charge-carrier transport and recombination in heteroepitaxial CdTe , 2014 .

[7]  D. Levi,et al.  Minority Carrier Lifetime Analysis in the Bulk of Thin-Film Absorbers Using Subbandgap (Two-Photon) Excitation , 2013, IEEE Journal of Photovoltaics.

[8]  Edward S. Barnard,et al.  Probing carrier lifetimes in photovoltaic materials using subsurface two-photon microscopy , 2013, Scientific Reports.

[9]  V. Buschmann,et al.  Spatially resolved measurements of charge carrier lifetimes in CdTe solar cells , 2013 .

[10]  Xufeng Wang,et al.  Design of GaAs Solar Cells Operating Close to the Shockley–Queisser Limit , 2013, IEEE Journal of Photovoltaics.

[11]  D. Levi,et al.  Impact of interface recombination on time resolved photoluminescence (TRPL) decays in CdTe solar cells (numerical simulation analysis) , 2012, 2012 38th IEEE Photovoltaic Specialists Conference.

[12]  W. Metzger How lifetime fluctuations, grain-boundary recombination, and junctions affect lifetime measurements and their correlation to silicon solar cell performance , 2008 .

[13]  Wilhelm Warta,et al.  Diffusion lengths of silicon solar cells from luminescence images , 2007 .

[14]  W. Metzger,et al.  The impact of charged grain boundaries on thin-film solar cells and characterization , 2005 .

[15]  D. Friedman,et al.  Analysis of charge separation dynamics in a semiconductor junction , 2005 .

[16]  D. Levi,et al.  Time-resolved photoluminescence studies of CdTe solar cells , 2003 .

[17]  Jeffrey A. Squier,et al.  High resolution nonlinear microscopy: A review of sources and methods for achieving optimal imaging , 2001 .

[18]  H. F. MacMillan,et al.  Minority‐carrier lifetime and photon recycling in n‐GaAs , 1992 .

[19]  Richard K. Ahrenkiel,et al.  Measurement of minority-carrier lifetime by time-resolved photoluminescence , 1992 .

[20]  Eli Zeldov,et al.  Steady‐state photocarrier grating technique for diffusion‐length measurement in semiconductors: Theory and experimental results for amorphous silicon and semi‐insulating GaAs , 1987 .

[21]  D. Aspnes,et al.  Summary Abstract: Nondestructive analysis of native oxides and interfaces on Hg1−xCdxTe , 1984 .

[22]  C. Jones,et al.  Minority carrier diffusion length in CdTe , 1982 .

[23]  D. Kuciauskas,et al.  Surface Passivation of CdTe Single Crystals , 2015, IEEE Journal of Photovoltaics.

[24]  R. Malik,et al.  Minority-Carrier Lifetime and Surface Recombination Velocity in Single-Crystal CdTe , 2015, IEEE Journal of Photovoltaics.

[25]  M. Young,et al.  Characterizing Recombination in CdTe Solar Cells with Time-Resolved Photoluminescence , 2006, 2006 IEEE 4th World Conference on Photovoltaic Energy Conference.

[26]  Richard K. Ahrenkiel,et al.  Chapter 2 Minority-Carrier Lifetime in III–V Semiconductors , 1993 .