Amorphous silicon transistors have been mechanically stressed, and the shift in transistor characteristics as a function of applied stress observed. This effect could be a problem for large area active matrix arrays for A4 liquid crystal display panels. Plasma deposited amorphous silicon always displays compressive stress, whereas the plasma grown silicon nitride can be deposited with tensile or compressive stress, depending on the gaseous precursors and reactor parameters. With careful selection of these parameters it is possible to grow a silicon/silicon nitride interface with a predetermined degree of stress.