The role of extended defects in device degradation

Grain boundaries and dislocations are well known to cause trouble in electronic devices, but in most cases they can be avoided by using single crystal films and eliminating or suppressing dislocation densities. Hetero‐interfaces, on the other hand, are essential features of devices. This papers reviews several topics from the author's published work, combining theoretical calculations with experimental data (microscopy, electrical measurements) to illustrate the interplay of impurities with extended defects, especially interfaces: dopant segregation in grain boundaries of polycrystalline Si, the role of hydrogen in the degradation of the Si–SiO 2 interface in Si‐based metal‐oxide‐semiconductor field‐effect transistors (MOSFETs), the role of carbon, nitrogen, and hydrogen in the quality and degradation of the SiC–SiO 2 interface in SiC‐based MOSFETs, and the role of vacancies in room‐temperature degradation of III–V high‐mobility electron transistors by the formation of microvoids.