Patent ID: 7492638

Claim:
A method of operating a nonvolatile memory device integrated circuit comprising a charge storage structure, one or more storage dielectric structures at least partly between the charge storage structure and a diode structure and at least partly between the charge storage structure and a source of gate voltage, the diode structure having a first node and a second node separated by a diffusion barrier junction, the method comprising: applying a first bias arrangement to determine a charge storage state of the charge storage structure, wherein the first node and the second node of the diode structure are at least partly adjacent to the one or more storage dielectric structures, and the diode structure has a cross-section in which the second node has opposite sides isolated from neighboring devices by isolation dielectric; and measuring current flowing through at least the diffusion barrier junction separating the first node and the second node of the diode structure, in reverse bias, to determine the charge storage state of the charge storage structure.