Universal memory element with systems employing same and apparatus and method for reading, writing and programming same

Claim 2

An encryption method of storing and retrieving information in a phase-change memory element having a phase-change memory material with at least a high resistance state and a detectably different low resistance state, said phase change material being capable of being set from said high resistance state to said low resistance state by a set energy pulse, said method comprising the steps of: storing information in said memory element by applying at least one program energy pulse to said phase change memory material, said at least one program energy pulse being insufficient to set said memory material from said high resistance state to a detectably different low resistance state but sufficient to modify said memory material so that the accumulation of said at least one program energy pulse with at least one additional program energy pulse sets said memory material from said high resistance state to a detectably different low resistance state; and retrieving information stored in said memory element by applying to said memory element additional program energy pulses until said memory element is caused to switch to its detectably different lower resistance state and counting the number of program energy pulses applied to cause said memory element to switch to its lower resistance state.

Claim 3

The method of claim 1, wherein said energy is electrical energy.

Claim 4

The method of claim 1, wherein said phase-change material includes one or more elements selected from the group consisting of Te, Se, Ge, Sb, Bi, Pb, Sn, As, S, Si, P, 0 and mixtures or alloys thereof.

Claim 5

The method of claim 3, wherein said phase-change material includes at least one chalcogen element and at least one transition metal element.

Claim 6

The method of programming of claim 4, wherein said chalcogen element is selected from the group of Te, Se and mixtures or alloys thereof.

Claim 7

The method of programming of claim 5, wherein said chalcogen element is a mixture of both Te and Se.

Claim 8

The method of programming of claim 6, wherein said at least one transition metal element is selected from the group consisting of Cr, Fe, Ni, Nb, Pd, Pt and mixtures or alloys thereof.

Claim 11

The method of claim 8, wherein said energy is electrical energy.

Claim 12

The method of claim 8, wherein said phase-change material includes one or more elements selected from the group consisting of Te, Se, Ge, Sb, Bi, Pb, Sn, As, S, Si, P, 0 and mixtures or alloys thereof.

Claim 13

The method of claim 10, wherein said phase-change material includes at least one chalcogen element and at least one transition metal element.

Claim 14

The method of programming of claim 11, wherein said chalcogen element is selected from the group of Te, Se and mixtures or alloys thereof.

Claim 15

The method of programming of claim 12, wherein said chalcogen element is a mixture of both Te And Se.

Claim 16

The method of programming of claim 13, wherein said at least one transition metal element is selected from the group consisting of Cr, Fe, Ni, Nb, Pd, Pt and mixtures or alloys thereof.

Claim 17

A control apparatus for controlling the level of connectivity between nodes in a nodal network of a neural network system comprising: a unit cell including a phase change material having at least a high resistance state and a low resistance state, said phase change material being capable of being set from said high resistance state to said low resistance state by a set energy pulse and from said low resistance state to said high resistance state by a reset energy pulse, first and second electrodes electrically connected to said phase change material for (a) applying electrical energy to said phase change material for switching said phase change material between its high resistance and low resistance states and (2) for establishing a signal conduction path through said phase change material when said phase change material is in its low resistance state; a control terminal and a signal terminal, both being electrically connected to said first electrode; a common control and signal terminal being connected to said second electrode; said signal terminal being electrically connected to a first node of said nodal network and said common control and signal terminal being electrically connected to a second node of said nodal network to control the level of connectivity between said first and second nodes; and a neural network control system electrically connected to said control terminal and to said common control and signal terminal for applying weighted control pulses to said phase change material to cause said phase change material to switch from its high resistance state to its low resistance state and thereby increase the level of connectivity between said first and second nodes when the cumulative effect of said control pulses exceeds the switching threshold level of said phase change material.

Claim 18

A control apparatus for controlling the level of connectivity between nodes in a nodal network of a neural network system comprising: a unit cell including a phase change material having at least a high resistance state and a low resistance state, said phase change material being capable of being set from said high resistance state to said low resistance state by a set energy pulse and from said low resistance state to said high resistance state by a reset energy pulse, first and second electrodes electrically connected to said phase change material for (a) applying electrical energy to said phase change material for switching said phase change material between its high resistance and low resistance states and (2) for establishing a signal conduction path through said phase change material when said phase change material is in its low resistance state; a control terminal and a signal terminal, both being electrically connected to said first electrode; a common control and signal terminal being connected to said second electrode; said signal terminal being electrically connected to a first node of said nodal network and said common control and signal terminal being electrically connected to a second node of said nodal network to control the level of connectivity between said first and second nodes; and a neural network control system electrically connected to said control terminal and to said common control and signal terminal for applying weighted control pulses to said phase change material to cause said phase change material to switch from its high resistance state to its low resistance state and thereby increase the level of connectivity between said first and second nodes when the cumulative effect of said control pulses exceeds the switching threshold level of said phase change material.

Claim 19

The control apparatus of claim 15, wherein said energy is electrical energy.

Claim 20

The control apparatus of claim 15, wherein said phase-change material includes one or more elements selected from the group consisting of Te, Se, Ge, Sb, Bi, Pb, Sn, As, S, Si, P, O and mixtures or alloys thereof.

Claim 21

The control apparatus of claim 17, wherein said phase-change material includes at least one chalcogen element and at least one transition metal element.

Claim 22

The control apparatus of claim 18, wherein said chalcogen element is selected from the group of Te, Se and mixtures or alloys thereof.

Claim 23

The control apparatus of claim 19, wherein said chalcogen element is a mixture of both Te and Se.

Claim 24

The control apparatus of claim 20, wherein said at least one transition metal element is selected from the group consisting of Cr, Fe, Ni, Nb, Pd, Pt and mixtures or alloys thereof.