Performance increase in ion-implanted p-channel MOST

In this paper, the effects of ion-implantation upon p-channel MOST structures in Si are discussed. A brief review of the literature on the subject of threshold shifting will be given. The paper will then describe how ion-implantation of boron beneath the gate of a p-channel MOST can change the mode of operation of the device from a surface channel device to a bulk device. (Commonly known as a deep depletion device.) Measurements will be presented of the change in "apparent" channel conductivity of the p-channel sturcture versus implanted boron concentration. It will be shown that under certain conditions "apparent" channel conductivities may be increased 60% over that of a comparative unimplanted device. Detailed analysis of the transfer characteristics of a number of implanted p-channel devices will be given and compared to unimplanted devices.