Simultaneous detection of electrically detected magnetic resonance and electron spin resonance using composite modulation

Abstract

Studies on the behavior of electron spins in the working states of organic and inorganic semiconductor devices are extremely important for understanding the mechanisms that cause the degradation of devices. Electrically detected magnetic resonance (EDMR) and electron spin resonance (ESR) spectroscopies are considered as effective and complementary methods in such studies. However, conventional attempts to monitor both types of spectra in real time have limitations owing to throughput performance and measurement optimization. To overcome these limitations, we present a composite modulation scheme, which applies microwave and magnetic field signals as a simultaneous detection method. The main principle is to use a periodic arbitrarily shaped microwave pulse and to burst a magnetic modulation signal in the latter half period when the microwave pulse is not applied. This scheme aids in measuring EDMR and ESR spectra simultaneously and tuning the measurement parameters of each spectrum independently. Furthermore, it becomes possible to estimate the number and g values of spins, which contribute to the recombination current from the correction by the ESR spectrum of standard samples. This method is expected to be a useful spectroscopic method for future studies on spintronics.