Effect of biaxial stress on Si(100) inversion layers

Biaxial compressive stress was produced on (100)Si MOS structures by differential thermal expansion coefficients between Si and epoxy. It was shown that the heavy mass band was shifted to the lower energy than the light mass band. However, the expected valley degeneracy of 4 was not observed. The SdH spectrum in this system shows phase reversal at about 4−5 × 1012 cm−2 due to exchange interaction enhanced spin splitting. It is shown that under certain conditions, transition between heavy to light mass bands and vice versa, can be observed in a single sample and the former appears to be nearly first order. © 1980, All rights reserved.