US 7,068,540 B2 · Method and device for programming an electrically programmable non-volatile semiconductor memory

Abstract

A device and method for programming an electrically programmable memory applies at least one first programming pulse to a group of memory cells (MC1–MCk) of the memory, accesses the memory cells of the group to ascertain a programming state thereof, and applies at least one second programming pulse to those memory cells in the group whose programming state is not ascertained to correspond to a desired programming state. A voltage applied to a control electrode of the memory cells is varied between the at least one first programming pulse and the at least one second programming pulse according to a forecasted change in biasing conditions of the memory cells in the group between said at least one first and at least one second programming pulses. Undesired over-programming of the memory cells is thus avoided.

Claims12

Dependent claims

A method of programming an electrically programmable memory, comprising:

applying at least one first programming pulse to a group of memory cells of an electrically programmable memory;
accessing the memory cells of the group to ascertain a programming state thereof;
and
applying at least one second programming pulse to those memory cells in the group whose programming state is not ascertained to correspond to a desired programming state, varying a voltage applied to a control electrode of the memory cells between the at least one first programming pulse and the at least one second programming pulse, wherein the varying the control electrode voltage comprises:
forecasting a change in biasing conditions of the memory cells in the group between the at least one first and at least one second programming pulses;
and
varying the control electrode voltage according to the forecasted change in biasing conditions.

4 more elements

A circuit for programming memory cells of an electrically programmable memory, comprising:

a circuit for applying programming pulses to selected groups of memory cells of an electrically programmable memory;
a variable voltage generator for supplying a variable programming voltage to a control electrode of the memory cells in the group;
and
a program verify circuit for accessing the memory cells in the group, ascertaining a programming state thereof and causing programming pulses to be repeatedly applied to the memory cells in the group until the programming state thereof is not ascertained to correspond to a desired programming state, varying the control electrode voltage;
wherein it comprises
means for forecasting a change in memory cell bias conditions between successive programming pulses and for causing the variable voltage generator to generate a voltage depending on the forecasted change in memory cell bias conditions.

3 more elements

Dependencies are inferred from the claim text.

Method and device for programming an electrically programmable non-volatile semiconductor memory

Life of this patent

Method and device for programming an electrically programmable non-volatile semiconductor memory

Life of this patent

Abstract

Claims12