Detrapping Current Measurement System Driven by Triboelectric Nanogenerators for Mapping Electron Trap States in Dielectrics

Electron trap states characterization plays a vital role in mesoscale measurement. Previous destructive methods have been applicable only in qualitative comparison. Nonetheless, the imaging of trap states distribution in space and energy level remains challenging. Herein, a triboelectric nanogenerator driven detrapping current (TENGd-DTC) measurement system is reported. The triboelectric nanogenerator (TENG) is designed as a high voltage generator, with an output voltage of ≈3 kV for driving the dielectric barrier discharge (DBD). The discharge model with dynamic carriers’ evolution is proposed, thus the detrapping currents can be extracted from DBD currents, based on which energy levels and densities of trap states are quantitatively calculated. The chamber design parameters as the platform for TENGd-DTC measurement under DBD are optimized. With the optimized chamber, the energy level range within 0.6–0.8 eV can be clearly characterized, and the difference between results of the proposed and the current methods is less than 12%. More importantly, the improved measurement electrode array is applied for multi-point scanning, and imaging of trap parameters is demonstrated vividly at a spatial resolution of ≈50 μm. This work paves an effective and non-destructive imaging approach for trap states characterization, and potential applications in mesoscale modification of functional materials.