公开(公告)号：FR2307334A1

公开(公告)日：1976-11-05

申请号：FR7534738

申请日：1975-11-07

Applicant: IBM

Inventor： ABRAS SHAKIR AHMED ,  DOCKERTY ROBERT CHARLES

IPC: G11C17/00 ,  G11C11/22 ,  G11C11/34 ,  G11C16/04 ,  H01L21/8247 ,  H01L29/788 ,  H01L29/792 ,  G11C11/40

Abstract: A non-volatile read mostly memory cell in a monocrystalline semiconductor body wherein the sensing of the information is achieved by measuring the substrate current. The cell includes spaced source and drain regions, a gate dielectric layer capable of trapping a charge, a substrate contact electrode; a means to induce a trapped charge into the gate dielectric layer, including a means to apply a voltage larger than the threshold voltage to the gate electrode to form an inversion layer, and a means to apply a voltage to the drain electrode causing channel current to flow; a means to remove the trapped charge, including a means to apply a voltage equal to or exceeding the avalanche voltage to the drain to cause avalanching; a means to determine the presence or absence of a charge in the gate dielectric including a means to apply a voltage to the gate which is larger than the threshold voltage and a voltage to the drain that is significantly less than the avalanche voltage, and a means to determine the substrate current.