System that compensates for coupling during programming
AssigneeSanDisk Corporation
InventorYan Li
Life of this patent
Estimating the term…
Abstract
Shifts in the apparent charge stored on a floating gate (or other charge storing element) of a non-volatile memory cell can occur because of the coupling of an electric field based on the charge stored in adjacent floating gates (or other adjacent charge storing elements). To compensate for this coupling, the read or programming process for a given memory cell can take into account the programmed state of an adjacent memory cell. To determine whether compensation is needed, a process can be performed that includes sensing information about the programmed state of an adjacent memory cell (e.g., on an adjacent bit line or other location).
Claims6
A non-volatile storage system, comprising:
- non-volatile storage elements including a first subset of said non-volatile storage elements and additional subsets of non-volatile storage elements;
- and
- a managing circuit in communication with said non-volatile storage elements, said managing circuit programs said first subset of said non-volatile storage elements to a first programmed state using one coarse verification level with a first coarse programming process and two fine verification levels with a fine programming process, said managing circuit programs said additional subsets of non-volatile storage elements to additional programmed states using one coarse verification level for each additional programmed state and one fine verification level for each additional programmed state, non-volatile storage elements of said first subset are not in said additional subsets.
Dependencies are inferred from the claim text.