OSCILLATIONS OF THE MAGNETORESISTANCE IN AN INCLINED MAGNETIC-FIELD FOR MIS STRUCTURES ON (100)SILICON WITH A HIGH ELECTRON-DENSITY

At electron densities N-s>6 x 10(12) cm(-2) a second series of oscilla tions, which are tentatively attributed to population of the second en ergy subband, is observed in addition to the main series of Shubnikov- de Haas oscillations. A change in phase of the oscillations of the sec ond series is observed at some angle of inclination alpha(e) of the fi eld. The measured value of alpha(e) is used to calculate the ratio of the cyclotron mass to the effective g factor. The maximum possible cyc lotron mass is also determined as m(H)<0.32m(e). On this basis it is c oncluded that the second series of oscillations is due to electrons wh ich have an in-plane effective mass mapproximate to 0.2m(e) and which belong to the same valleys of the Fermi surface as in the case of the main oscillations. (C) 1998 American Institute of Physics.