US5128099A
Expired / Lapsed
US
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Congruent state changeable optical memory material and device
Assignee: Optical Memory Storage LLC
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Filing: 1991-02-15
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Granted: 1992-07-07
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Expires: 2011-02-15
Abstract
Abstract A state changeable memory alloy and device employing same. The memory alloy is capable of changing from a first state to a second state in response to the input of energy, such as projected optical beam energy, electrical energy or thermal energy. The alloy has a first detectable characteristic when in the first state and a second detectable characteristic when in the second state. It is further characterized in that the first state comprises a single phase, and the second state comprises either: (1) a single phase having the same composition as the first phase or (2) a plurality of phases which have substantially similar crystallization temperatures and kinetics. <IMAGE>
Inventors
- 👤 David A. Strand
- 👤 Stanford R. Ovshinsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:41
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/26; G11C; G11C13/00; G11C13/04; G11B7/004; G11B7/0055; G11B7/00557; G11B7/241; G11B7/242; G11B7/243; G11C13/047; G11C7/00; G11C7/005; G11B2007/24302; G11B2007/24312; G11B2007/24314; G11B2007/24316
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
113 words
A state changeable memory alloy changeable from a first state to a second state in response to the input of energy, said alloy having a first detectable characteristic when in said first state and a second detectable characteristic when in said second state, and said first and second detectable characteristics selected from the group consisting of reflectivity, band gap, electrical resistance, optical absorption, magnetic susceptibility and thermal conductivity; said alloy further characterized in that the first state comprises a single phase and said second state comprises either (1) a single phase having the same composition as said first state or (2) a plurality of phases which have substantially similar crystallization temperatures and kinetics.
Claim 2
Dependent Claim
113 words
A state changeable memory alloy changeable from a first state to a second state in response to the input of energy, said alloy having a first detectable characteristic when in said first state and a second detectable characteristic when in said second state, and said first and second detectable characteristics selected from the group consisting of reflectivity, band gap, electrical resistance, optical absorption, magnetic susceptibility and thermal conductivity; said alloy further characterized in that the first state comprises a single phase and said second state comprises either (1) a single phase having the same composition as said first state or (2) a plurality of phases which have substantially similar crystallization temperatures and kinetics.
Claim 3
Dependent Claim
11 words
An alloy as in claim 1, which comprises a chalcogenide material.
Claim 4
Dependent Claim
12 words
An alloy as in claim 1, which comprises at least three elements.
Claim 5
Dependent Claim
12 words
An alloy as in claim 1 which comprises Te, Ge and Sb.
Claim 6
Dependent Claim
27 words
An alloy as in claim 1 which is capable of changing from said first state to said second state in response to the input of optical energy.
Claim 7
Dependent Claim
27 words
An alloy as in claim 1, which is capable of changing from said first state to said second state in response to the input of electrical energy.
Claim 8
Dependent Claim
27 words
An alloy as in claim 1, which is capable of changing from said first state to said second state in response to the input of thermal energy.
Claim 9
Dependent Claim
22 words
An alloy as in claim 1, wherein said first state is an amorphous state and said second state is a crystalline state.
Claim 10
Dependent Claim
17 words
The material of claim 1 wherein said material is substantially entirely crystalline when in said crystalline state.
Claim 11
Dependent Claim
160 words
A congruent state changeable, chalcogenide, optical memory material capable of existing in at least an amorphous state and a crystalline state, said material having a first detectable physical characteristic or properties index when in the crystalline state and a second detectable physical characteristic or properties index when in the amorphous state and being capable of undergoing a congruent state change upon the application of projected beam energy thereto, said material being of the composition: Te.sub.a Ge.sub.b Sb.sub.c a, b and c being expressed in atomic percentages and selected such that, when said material is in the crystalline state, and it includes a major portion which has the same composition as the material has when in the amorphous state and a minor portion which has the composition: Te.sub.d Ge.sub.e Sb.sub.f, d, e and f being expressed in atomic percentages wherein the differences between a and d, b and e, and c and f, respectively, total no more than 16 atomic percent.
Claim 12
Dependent Claim
160 words
A congruent state changeable, chalcogenide, optical memory material capable of existing in at least an amorphous state and a crystalline state, said material having a first detectable physical characteristic or properties index when in the crystalline state and a second detectable physical characteristic or properties index when in the amorphous state and being capable of undergoing a congruent state change upon the application of projected beam energy thereto, said material being of the composition: Te.sub.a Ge.sub.b Sb.sub.c a, b and c being expressed in atomic percentages and selected such that, when said material is in the crystalline state, and it includes a major portion which has the same composition as the material has when in the amorphous state and a minor portion which has the composition: Te.sub.d Ge.sub.e Sb.sub.f, d, e and f being expressed in atomic percentages wherein the differences between a and d, b and e, and c and f, respectively, total no more than 16 atomic percent.
Claim 13
Dependent Claim
25 words
The material of claim 10 wherein a is from 49 to 53, b is from 36 to 40 and c is from 9 to 13.
Claim 14
Dependent Claim
13 words
The material of claim 10 further comprising a third portion of varying composition.
Claim 15
Dependent Claim
24 words
The material of claim 10 wherein the material switches from the amorphous to the crystalline state upon the application of projected beam energy thereto.
Claim 16
Dependent Claim
16 words
The material of claim 10 wherein the congruent state change temperature is at least 200° C.
Claim 17
Dependent Claim
22 words
The material of claim 13 wherein data is recorded upon the material by switching it from the amorphous to the crystalline state.
Claim 18
Dependent Claim
24 words
The material of claim 13 wherein the material is reversibly switchable between the amorphous and crystalline states by application of projected beam energy thereto.
Claim 19
Dependent Claim
18 words
The material of claim 15 wherein the material has a usable upper frequency of at least 6 MhZ.
Claim 20
Dependent Claim
37 words
The material of claim 16 wherein data is recorded upon the material by switching it from the amorphous to the crystalline state and erased from the material by switching it from the crystalline to the amorphous state.
Claim 21
Dependent Claim
15 words
The material of claim 18 wherein the projected beam energy is supplied by a laser.
Claim 22
Dependent Claim
37 words
The material of claim 19 wherein the first detectable property is the optical reflectivity of the material in the amorphous state and the second detectable property is the optical reflectivity of the material in the crystalline state.
Claim 23
Dependent Claim
28 words
The material of claim 20 wherein the ratio between the first and second detectable states (relative reflectivity) at the threshold record laser power is between 2 and 3.
Claim 24
Dependent Claim
21 words
The material of claim 21 wherein the carrier to noise ratio is at least 45 db at the threshold record power.
Claim 25
Dependent Claim
113 words
A state changeable memory alloy changeable from a first state to a second state in response to the input of energy, said alloy having a first detectable physical characteristic or properties index when in said first state and a second detectable physical characteristic or properties index when in said second state, said alloy having the general formula Te 50 (GeX) 50 wherein X is Sb, Sn or Bi, said alloy further characterized in that the first state comprises a single phase and said second state comprises either (1) a single phase having the same composition as said first state or (2) a plurality of phases which have substantially similar crystallization temperatures and kinetics.
Claim 26
Dependent Claim
113 words
A state changeable memory alloy changeable from a first state to a second state in response to the input of energy, said alloy having a first detectable physical characteristic or properties index when in said first state and a second detectable physical characteristic or properties index when in said second state, said alloy having the general formula Te 50 (GeX) 50 wherein X is Sb, Sn or Bi, said alloy further characterized in that the first state comprises a single phase and said second state comprises either (1) a single phase having the same composition as said first state or (2) a plurality of phases which have substantially similar crystallization temperatures and kinetics.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-07-07 | 1996-01-06 | 1996-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-07 | 2000-01-06 | 2000-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-07 | 2004-01-06 | 2004-07-07 | $7700.00 | Window Closed / Lapsed |