Patent ID: 7342817
Filing Date: 2008-03-11
Classification: G11C

Abstract:
1. A system for writing data using a focused electron beam source to change the structure of a portion of a storage medium, the focused electron beam source having an electron emitting tip, and an aperture being conductive and having a through hole aligned with the electron emitting tip such that a first portion of the electrons emitted by the electron emitting tip impacts against the aperture and a second portion of the electrons emitted by the electron emitting tip passes through the through hole, and at least a portion of the second portion of the electrons emitted by the electron emitting tip impacts against the storage medium, the system comprising: a controller controlling a first current flow to the electron emitting tip based on a second current flow in the storage medium and based on a third current flow in the aperture to begin a write cycle, wherein the controller switches off the first current flow to the electron emitting to stop the write cycle when a magnitude of the third current flow in the aperture differs from a prior magnitude of the third current flow in the aperture by at least a pre-determined percentage, and then switches on the first current flow to the electron emitting tip to continue the write cycle.