ABSTRACT
Admittance measurements are a simple and straightforward technique for measuring electronic properties of contacted semiconductor devices. Typical devices to which admittance spectroscopy can be applied include pn-diodes, photodiodes, transistors, and solar cells. This chapter focuses on admittance measurements applied to thin-film solar cell devices. Capacitance and conductance data gathered as a function of temperature and probe frequency are able to elucidate key information about these signals, including activation energies. A very simple method to calibrate the response of a lock-in amplifier to a known capacitance is to substitute a capacitor with a known value into the measurement system. CuZnSnSe2 devices are known for their optimal band gap match to the solar spectrum and their reliance only on abundant materials. Methylammonium lead triiodide has seen enormous developments in peak research cell efficiency and a significant amount of attention as a low cost, solution processed, high quality material for solar energy harvesting.
