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201502 https://hdl.handle.net/2286/R.2.N.201502 http://rightsstatements.org/vocab/InC/1.0/ All Rights Reserved 2025 209 pages Doctoral Dissertation Academic theses en Mahaffey, Mason Philip Holman, Zachary Onno, Arthur King, Richard Rolston, Nicholas Arizona State University Partial requirement for: Ph.D., Arizona State University, 2025 Field of study: Electrical Engineering A measurement tool for assessing the injection-dependent photoluminescence (PL) intensity of semiconductors, called the Suns–External-Radiative-Efficiency (Suns–ERE) tool, was developed. This quasi-steady-state PL tool measures the ERE and minority carrier lifetime of a sample as a function of the steady-state light intensity. From this information, it is possible to calculate the implied voltage and doping concentration of semiconductor films. First, the use of the Suns–ERE tool is demonstrated through measurements of the ERE and implied voltage of a gallium arsenide heterostructure. There are less than 2 millivolts of difference between the value calculated by the Suns–ERE tool and that of a calibrated hyperspectral PL microscope. Then, the tool is used to measure both the minority carrier lifetime and the doping concentration of silicon (Si), Cadmium(Selenium)Telluride (Cd(Se)Te), and perovskite absorbers. The tool is able to measure Si doping concentration values within a factor of 2 of known reference techniques, the measured doping values of Cd(Se)Te films are in good agreement with capacitance-voltage-measured doping concentrations. Additional consideration is given to the measurement of doping on perovskite films. It is shown that perovskite PL instability leads to inaccuracies in the measured doping, and that sample encapsulation helps with film stability. Simulations are performed to confirm the impact of optoelectronic instabilities on measurements. With context from simulation, doping concentration measurements are shown on encapsulated and unencapsulated films. The results demonstrate that there is significant variation in doping between films, different locations on films, and between perovskite grown on different surfaces. Finally, the use of the tool is expanded to measure the implied voltage of metallized Si solar cells. The tool is not able to measure the expected implied voltage because the tool’s illumination area is smaller than the cells’ full area. The differences between measurements made with the Suns–ERE tool and a full-area PL tool are highlighted. The tool is shown to be useful in quantitatively tracking changes in implied voltage, and a second version of the tool produces more accurate implied voltage measurements using a larger laser area (which is still partial relative to the size of the Si sample). Electrical Engineering Applied physics Materials Science Doping external radiative efficiency Perovskite Photoluminescence Solar Cell Measurements Solar Cells Understanding Solar Cell Performance Using Light-Based Measurement Techniques