Impact of Strain on Bond Structure

This lecture delves into the impact of strain on the bond structure, focusing on the energy shifts experienced by heavy hole and light hole balance bonds, the ordering of bond energy levels, and the implications of shear strain on semiconductors. The instructor explains how strain affects the symmetry of bond structures, leading to changes in the valence bond states and the bond gap. Practical examples, such as a silicon germanium-based MOSFET, are used to illustrate how strain engineering can enhance device performance. The lecture concludes by discussing the experimental exploration of strain effects through hydrostatic pressure and biaxial strain, emphasizing the importance of understanding and utilizing strain in semiconductor technology.