Grenzflächenstellen

Grenzflächenstellen, meaning "interface states" in English, refers to electronic states that exist within the band gap of a semiconductor at the interface between two different materials. These interfaces can be between a semiconductor and a metal (Schottky contact), a semiconductor and an insulator (MIS structure), or between two different semiconductors (heterojunction). These states arise from the disruption of the crystal lattice periodicity at the interface, leading to dangling bonds, impurities, or other structural defects.

The presence of Grenzflächenstellen can significantly influence the electrical properties of semiconductor devices. They can act as trapping centers for charge carriers, affecting carrier mobility and lifetime. They can also contribute to leakage currents, recombination processes, and band bending at the interface. The density and energy distribution of these interface states are crucial parameters for device performance, particularly in applications like transistors, solar cells, and sensors. Techniques such as capacitance-voltage (C-V) measurements and deep-level transient spectroscopy (DLTS) are commonly used to characterize Grenzflächenstellen. Understanding and controlling these states is essential for optimizing device design and fabrication.