US4646266A
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US
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Programmable semiconductor structures and methods for using the same
Assignee: Energy Conversion Devices Inc
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Filing: 1984-09-28
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Granted: 1987-02-24
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Expires: 2004-09-28
Abstract
Abstract A solid state semiconductor device is disclosed which is programmable so as to alter the impedance between its two terminals. In many embodiments, the device is programmable to have any one of four conditions: a first in which the electrical impedance is relatively high in both directions; a second in which the impedance is relatively high in one direction and relatively low in the opposite direction; a third in which the impedance is relatively high in the opposite direction and relatively low in the first direction; and a fourth in which the impedance is relatively low in both directions. Such a programmable device can be made with semiconductor layers which form two series coupled back-to-back diodes, each of which can be selectively programmed to lose its rectifying feature. Structures are disclosed which include a plurality of such programmable devices in one or more separately programmable planes, each with its own addressing means. Programmable logic arrays can be formed out of such multilayered cell structures, including programmable logic arrays, in which the AND and OR planes are vertically disposed one on top of the other.
Inventors
- 👤 Stanford R. Ovshinsky
- 👤 Robert R. Johnson
- 👤 Vincent D. Cannella
- 👤 Zvi Yaniv
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:46
CPC Classifications
H; H10; H10D; H10D48/00; H10D48/30; H10D48/38; H10D48/381; H10D84/00; H10D84/90; H10D88/00; H10B; H10B63/00; Y; Y10; Y10S; Y10S257/00; Y10S257/926
Claims Analysis
Total Claims: 95
Claim 1
Independent Claim
120 words
A solid state semiconductor device having at least two terminals and a plurality of layers of semiconductor material to provide a plurality of interacting semiconductor functions, said device being programmable in a first condition in which the electrical impedance between said two terminals is relatively high in both directions, a second condition in which the electrical impedance between said two terminals is relatively high in one direction and relatively low in the opposite direction, a third condition in which the electrical impedance between said two terminals is relatively high in said opposite direction and relatively low in said one direction, and a fourth condition in which the electrical impedance between said two terminals is relatively low in both said directions.
Claim 2
Dependent Claim
120 words
A solid state semiconductor device having at least two terminals and a plurality of layers of semiconductor material to provide a plurality of interacting semiconductor functions, said device being programmable in a first condition in which the electrical impedance between said two terminals is relatively high in both directions, a second condition in which the electrical impedance between said two terminals is relatively high in one direction and relatively low in the opposite direction, a third condition in which the electrical impedance between said two terminals is relatively high in said opposite direction and relatively low in said one direction, and a fourth condition in which the electrical impedance between said two terminals is relatively low in both said directions.
Claim 3
Dependent Claim
27 words
A device as defined in claim 1, wherein said device is manufactured in one of said conditions and programmable into any one of said remaining three conditions.
Claim 4
Dependent Claim
16 words
A device as defined in claim 2, wherein said device is manufactured in said first condition.
Claim 5
Dependent Claim
18 words
A device as defined in claim 1, wherein said device includes at least one layer of phase-changeable material.
Claim 6
Dependent Claim
16 words
A device as defined in claim 4, wherein said phase-changeable material comprises an amorphous semiconductor alloy.
Claim 7
Dependent Claim
14 words
A device as defined in claim 5, wherein said amorphous semiconductor alloy includes silicon.
Claim 8
Dependent Claim
14 words
A device as defined in claim 5, wherein said amorphous semiconductor alloy includes germanium.
Claim 9
Dependent Claim
17 words
A device as defined in claim 5, wherein said amorphous semiconductor alloy includes both silicon and germanium.
Claim 10
Dependent Claim
29 words
A device as defined in claim 1 wherein said plurality of layers of semiconductor material form a pair of series coupled back-to-back diodes for providing said interacting semiconductor functions.
Claim 11
Dependent Claim
13 words
A device as defined in claim 9 including metal between said back-to-back diodes.
Claim 12
Dependent Claim
67 words
A device as defined in claim 1, wherein said device has at least two interacting semiconductor functions and wherein said device further includes a third terminal for separately accessing at least one of said semiconductor functions between said third terminal and a first of said two terminals and at least one other of said semiconductor functions between said third terminal and the other of said two terminals.
Claim 13
Dependent Claim
142 words
A solid state semiconductor cell structure having at least two terminal planes and a plurality of layers of semiconductor material to provide a plurality of interacting semiconductor functions, said cell structure being programmable in a first condition in which the electrical impedance between said two planes is relatively high in both directions, a second condition in which the electrical impedance between said two planes is relatively high in one direction and relatively low in the opposite direction, a third condition in which the electrical impedance between said two planes is relatively high in said opposite direction and relatively low in said one direction, and a fourth condition in which the electrical impedance between said two planes is relatively low in both said directions, and addressing means for programming said cell structure at unique selected locations thereof into any one of said conditions.
Claim 14
Dependent Claim
142 words
A solid state semiconductor cell structure having at least two terminal planes and a plurality of layers of semiconductor material to provide a plurality of interacting semiconductor functions, said cell structure being programmable in a first condition in which the electrical impedance between said two planes is relatively high in both directions, a second condition in which the electrical impedance between said two planes is relatively high in one direction and relatively low in the opposite direction, a third condition in which the electrical impedance between said two planes is relatively high in said opposite direction and relatively low in said one direction, and a fourth condition in which the electrical impedance between said two planes is relatively low in both said directions, and addressing means for programming said cell structure at unique selected locations thereof into any one of said conditions.
Claim 15
Dependent Claim
63 words
A cell structure as defined in claim 12, wherein said addressing means comprises a first plurality of spaced apart address lines on one of said terminal planes and a second plurality of spaced apart address lines on said other terminal plane crossing said first plurality of address lines at an angle to form a plurality of crossover points defining said unique selected locations.
Claim 16
Dependent Claim
34 words
A cell structure as defined in claim 12, wherein said cell structure is manufactured in one of said conditions and programmable at said unique selected locations into any one of said remaining three conditions.
Claim 17
Dependent Claim
18 words
A cell structure as defined in claim 14, wherein said cell structure is manufactured in said first condition.
Claim 18
Dependent Claim
21 words
A cell structure as defined in claim 12, wherein said cell structure includes at least one layer of phase changeable material.
Claim 19
Dependent Claim
18 words
A cell structure as defined in claim 16, wherein said phase changeable material comprises an amorphous semiconductor alloy.
Claim 20
Dependent Claim
15 words
A cell structure as defined in claim 17, wherein said amorphous semiconductor alloy includes silicon.
Claim 21
Dependent Claim
15 words
A cell structure as defined in claim 17, wherein said amorphous semiconductor alloy includes germanium.
Claim 22
Dependent Claim
17 words
A cell structure as defined in claim 17, wherein said amorphous semiconductor alloy includes silicon and germanium.
Claim 23
Dependent Claim
30 words
A cell structure as defined in claim 12 wherein said plurality of layers of semiconductor material form a pair of series coupled back-to-back diodes for providing said interacting semiconductor functions.
Claim 24
Dependent Claim
14 words
A cell structure as defined in claim 21 including metal between said back-to-back diodes.
Claim 25
Dependent Claim
75 words
A cell structure as defined in claim 12, wherein said cell structure has at least two interacting semiconductor functions and wherein said cell structure further includes a third terminal plane for separately accessing at least one of said semiconductor functions between said third terminal plane and a first of said two terminal planes and at least one other of said semiconductor functions between said third terminal plane and the other of said two terminal planes.
Claim 26
Dependent Claim
30 words
A programmable cell structure comprising a first plurality of vertically arrayed layers of semiconductor materials arranged to form at least a first pair of series connected vertically disposed back-to-back diodes.
Claim 27
Dependent Claim
30 words
A programmable cell structure comprising a first plurality of vertically arrayed layers of semiconductor materials arranged to form at least a first pair of series connected vertically disposed back-to-back diodes.
Claim 28
Dependent Claim
14 words
A cell structure as defined in claim 24 including metal between said back-to-back diodes.
Claim 29
Dependent Claim
16 words
A cell structure as defined in claim 24, wherein said semiconductor materials are deposited semiconductor materials.
Claim 30
Dependent Claim
18 words
A cell structure as defined in claim 26, wherein said deposited semiconductor materials are amorphous semiconductor alloy materials.
Claim 31
Dependent Claim
16 words
A cell structure as defined in claim 27, wherein said amorphous semiconductor alloy materials include silicon.
Claim 32
Dependent Claim
16 words
A cell structure as defined in claim 27, wherein said amorphous semiconductor alloy materials include germanium.
Claim 33
Dependent Claim
19 words
A cell structure as defined in claim 27, wherein said amorphous semiconductor alloy materials include both silicon and germanium.
Claim 34
Dependent Claim
33 words
A cell structure as defined in claim 24 further including means for dividing said first pair of series connected vertically disposed back-to-back diodes into plural pairs of series connected vertically disposed back-to-back diodes.
Claim 35
Dependent Claim
28 words
A cell structure as defined in claim 31 including a separate portion of metal between the back-to-back diodes of each of said plural pairs of said back-to-back diodes.
Claim 36
Dependent Claim
55 words
A cell structure as defined in claim 24 further including a second plurality of vertically arrayed layers of semiconductor materials formed on said first plurality of vertically arrayed layers of semiconductor materials to form a second pair of series connected vertically disposed back-to-back diodes over said first pair of series connected vertically disposed back-to-back diodes.
Claim 37
Dependent Claim
40 words
A cell structure as defined in claim 33 further including means for dividing each said first and second pairs of series connected vertically disposed back-to-back diodes into first and second respective plural pairs of series connected vertically disposed back-to-back diodes.
Claim 38
Dependent Claim
33 words
A cell structure as defined in claim 34, wherein selected ones of said diodes of said first and second plural pairs of diodes are short circuited for forming a folded programmable logic array.
Claim 39
Dependent Claim
102 words
An integrated circuit comprising: a multilayered structure of deposited layers of various materials including semiconductor alloy materials, said layers of semiconductor alloy materials being initially deposited as continuous layers, said layers being arranged to provide programmable semiconductor interactions between at least some of said layers so as to perform selected electrical functions at unique selected locations, and to provide said programmable semiconductor interactions in two separate subsets, each separately programmable from the other; and addressing means for defining said unique selected locations and for enabling the programming of said semiconductor interactions of said semiconductor alloy material layers at said unique selected locations.
Claim 40
Dependent Claim
102 words
An integrated circuit comprising: a multilayered structure of deposited layers of various materials including semiconductor alloy materials, said layers of semiconductor alloy materials being initially deposited as continuous layers, said layers being arranged to provide programmable semiconductor interactions between at least some of said layers so as to perform selected electrical functions at unique selected locations, and to provide said programmable semiconductor interactions in two separate subsets, each separately programmable from the other; and addressing means for defining said unique selected locations and for enabling the programming of said semiconductor interactions of said semiconductor alloy material layers at said unique selected locations.
Claim 41
Dependent Claim
18 words
An integrated circuit as defined in claim 36, wherein said deposited semiconductor materials are amorphous semiconductor alloy materials.
Claim 42
Dependent Claim
16 words
An integrated circuit as defined in claim 37, wherein said amorphous semiconductor alloy materials include silicon.
Claim 43
Dependent Claim
16 words
An integrated circuit as defined in claim 37, wherein said amorphous semiconductor alloy materials include germanium.
Claim 44
Dependent Claim
19 words
An integrated circuit as defined in claim 37, wherein said amorphous semiconductor alloy materials include both silicon and germanium.
Claim 45
Dependent Claim
24 words
An integrated circuit as defined in claim 36, wherein at least one of said layers of semiconductor alloy material is a phase changeable material.
Claim 46
Dependent Claim
26 words
An integrated circuit as defined in claim 36, wherein said layers of semiconductor alloy materials initially form a pair of series coupled vertically disposed back-to-back diodes.
Claim 47
Dependent Claim
14 words
An integrated circuit as defined in claim 42 including metal between said back-to-back diodes.
Claim 48
Dependent Claim
35 words
An integrated circuit as defined in claim 42, wherein said addressing means forms means for dividing said pair of series connected vertically disposed back-to-back diodes into plural pairs of series connected vertically disposed back-to-back diodes.
Claim 49
Dependent Claim
28 words
An integrated circuit as defined in claim 44 including a separate portion of metal between the back-to-back diodes of each of said plural pairs of said back-to-back diodes.
Claim 50
Dependent Claim
67 words
An integrated circuit as defined in claim 36, wherein said addressing means comprises a first plurality of spaced apart address lines on one side of said multilayered structure and a second plurality of spaced apart address lines on the other side of said multilayered structure crossing said first plurality of address lines at an angle to form a plurality of crossover points defining said unique selected locations.
Claim 51
Dependent Claim
87 words
A programmable logic array comprising a multilayered structure of a plurality of vertically arrayed layers of various materials including deposited semiconductor alloy materials, said layers of semiconductor materials being initially deposited as continuous layers and at least some of said layers of various materials being arranged to provide semiconductor interactions between said layers for providing individually programmable selected logic functions across said structure at selected locations thereof; and means defining said selected locations and for enabling the programming of said selected logic functions at said selected locations.
Claim 52
Dependent Claim
87 words
A programmable logic array comprising a multilayered structure of a plurality of vertically arrayed layers of various materials including deposited semiconductor alloy materials, said layers of semiconductor materials being initially deposited as continuous layers and at least some of said layers of various materials being arranged to provide semiconductor interactions between said layers for providing individually programmable selected logic functions across said structure at selected locations thereof; and means defining said selected locations and for enabling the programming of said selected logic functions at said selected locations.
Claim 53
Dependent Claim
18 words
A logic array as defined in claim 47, wherein said logic functions include AND and OR logic functions.
Claim 54
Dependent Claim
25 words
A logic array as defined in claim 47, wherein said layers of deposited semiconductor material form a pair of series coupled vertically disposed back-to-back diodes.
Claim 55
Dependent Claim
14 words
A logic array as defined in claim 49 including metal between said back-to-back diodes.
Claim 56
Dependent Claim
33 words
A logic array as defined in claim 47 including a pair of said multilayered structures, said structures being vertically arrayed to form a pair of programmable logic planes superposed one over the other.
Claim 57
Dependent Claim
29 words
A logic array as defined in claim 51, wherein said structures are programmed to provide an AND logic plane and an OR logic plane superposed one over the other.
Claim 58
Dependent Claim
76 words
A programmable logic array comprising a multilayered structure of a plurality of vertically arrayed layers of semiconductor materials to form a pair of series connected vertically disposed back-to-back diodes; and means for dividing said pair of series connected vertically disposed back-to-back diodes into plural pairs of series connected vertically disposed back-to-back diodes and for enabling the short circuiting of selected ones of said diodes for programming groups of said diode pairs to provide selected logic functions.
Claim 59
Dependent Claim
76 words
A programmable logic array comprising a multilayered structure of a plurality of vertically arrayed layers of semiconductor materials to form a pair of series connected vertically disposed back-to-back diodes; and means for dividing said pair of series connected vertically disposed back-to-back diodes into plural pairs of series connected vertically disposed back-to-back diodes and for enabling the short circuiting of selected ones of said diodes for programming groups of said diode pairs to provide selected logic functions.
Claim 60
Dependent Claim
28 words
A logic array as defined in claim 53 including a separate portion of metal between the back-to-back diodes of each of said plural pairs of said back-to-back diodes.
Claim 61
Dependent Claim
27 words
A logic array as defined in claim 53 including a pair of said multilayered structures, one superposed over the other, to form a folded programmable logic array.
Claim 62
Dependent Claim
42 words
A logic array as defined in claim 55, wherein the diode pairs of one of said structures are programmed to form an AND logic plane and the diode pairs of the other said structure are programmed to form an OR logic plane.
Claim 63
Dependent Claim
98 words
A solid state semiconductor programmable switch comprising a plurality of layers of semiconductor material to form at least two series connected vertically disposed cell portions; said cell portions being individually programmable for permitting the conduction of current through said switch in only a first direction, or for permitting the conduction of current through said switch in only a second direction opposite said first direction, or for permitting the conduction of current through said switch in both said first and second directions; or for preventing the conduction of current through said switch in either said first or second directions.
Claim 64
Dependent Claim
98 words
A solid state semiconductor programmable switch comprising a plurality of layers of semiconductor material to form at least two series connected vertically disposed cell portions; said cell portions being individually programmable for permitting the conduction of current through said switch in only a first direction, or for permitting the conduction of current through said switch in only a second direction opposite said first direction, or for permitting the conduction of current through said switch in both said first and second directions; or for preventing the conduction of current through said switch in either said first or second directions.
Claim 65
Dependent Claim
18 words
A programmable switch as defined in claim 57, wherein said cell portions comprise a pair of back-to-back diodes.
Claim 66
Dependent Claim
31 words
A programmable switch as defined in claim 58, wherein said cell portions are initially formed to prevent the conduction of current through said switch in either said first or second directions.
Claim 67
Independent Claim
131 words
A method of programming a solid state semiconductor device having a plurality of semiconductor functions in series between a first and a second terminal, said semiconductor functions including a first subset which provides a relatively high impedance in a first direction along said series and a relatively low impedance in a second, opposite, direction along said series, and a second subset which provides a relatively high impedance in said second direction and a relatively low impedance in said first direction, said method comprising forming said device by depositing a plurality of layers of semiconductor material to provide said plurality of semiconductor functions, and selectively programming at least one semiconductor function of said first subset by applying a programming voltage across at least a portion of said device in said first direction.
Claim 68
Independent Claim
131 words
A method of programming a solid state semiconductor device having a plurality of semiconductor functions in series between a first and a second terminal, said semiconductor functions including a first subset which provides a relatively high impedance in a first direction along said series and a relatively low impedance in a second, opposite, direction along said series, and a second subset which provides a relatively high impedance in said second direction and a relatively low impedance in said first direction, said method comprising forming said device by depositing a plurality of layers of semiconductor material to provide said plurality of semiconductor functions, and selectively programming at least one semiconductor function of said first subset by applying a programming voltage across at least a portion of said device in said first direction.
Claim 69
Dependent Claim
44 words
A method of programming a solid state semiconductor device as described in claim 60, further comprising selectively programming at least one semiconductor function of said second subset by applying a programming voltage across at least a portion of said device in said second direction.
Claim 70
Dependent Claim
29 words
A method of programming a solid state semiconductor device as described in claim 60, wherein said applying of said programming voltage includes applying said voltage between said two terminals.
Claim 71
Dependent Claim
75 words
A method of programming a solid state semiconductor device as described in claim 60, wherein said device includes a third terminal, and said at least one semiconductor function of said first subset is between said first and third terminals and said at least one semiconductor function of said second subset is between said second and third terminals, and said applying of said programming voltage includes applying said programming voltage between said first and third terminals.
Claim 72
Dependent Claim
69 words
A method of programming a solid state semiconductor device as described in claim 60, wherein said semiconductor functions of said first and second subsets are provided by rectifying semiconductor junctions and said applying of said programming voltage includes applying a programming voltage of sufficient magnitude to cause a breakdown current across at least one said rectifying junction which provides said at least one semiconductor function of said first set.
Claim 73
Dependent Claim
67 words
A method of programming a solid state semiconductor device as described in claim 64, wherein said at least one rectifying junction includes phase changeable semiconductor material and said selectively programming said at least one semiconductor function of said first subset includes causing sufficient breakdown current to flow across said at least one rectifying junction so as to cause a phase change in the material of said junction.
Claim 74
Dependent Claim
123 words
An electrical circuit comprising: a first conductor; a second conductor; and a programmable solid state semiconductor device connected between said first and second conductors, said device having a plurality of layers of semiconductor material to form a plurality of semiconductor junctions connected in electrical series between said conductors, said semiconductor junctions including a first subset which provides a relatively high impedance in a first direction along said series and a relatively low impedance in a second, opposite, direction along said series, and a second subset which provides a relatively high impedance in said second direction and a relatively low impedance in said first direction, said circuit being originally formed with a relatively high impedance in both directions between said first and second conductors.
Claim 75
Dependent Claim
123 words
An electrical circuit comprising: a first conductor; a second conductor; and a programmable solid state semiconductor device connected between said first and second conductors, said device having a plurality of layers of semiconductor material to form a plurality of semiconductor junctions connected in electrical series between said conductors, said semiconductor junctions including a first subset which provides a relatively high impedance in a first direction along said series and a relatively low impedance in a second, opposite, direction along said series, and a second subset which provides a relatively high impedance in said second direction and a relatively low impedance in said first direction, said circuit being originally formed with a relatively high impedance in both directions between said first and second conductors.
Claim 76
Dependent Claim
55 words
An electrical circuit as described in claim 66, wherein said programmable device includes two back-to-back diodes and wherein said first subset of semiconductor junctions include a rectifying semiconductor junction of a first of said back-to-back diodes and said second subset of semiconductor junctions includes a rectifying semiconductor junction of the other of said back-to-back diodes.
Claim 77
Dependent Claim
23 words
An electrical circuit as described in claim 67, wherein at least said first of said back-to-back diodes includes deposited, phase changeable semiconductor material.
Claim 78
Dependent Claim
18 words
An electrical circuit as described in claim 68, wherein said phase changeable material comprises an amorphous semiconductor alloy.
Claim 79
Dependent Claim
13 words
An electrical circuit as described in claim 69, wherein said alloy includes silicon.
Claim 80
Dependent Claim
13 words
An electrical circuit as described in claim 70, wherein said alloy includes hydrogen.
Claim 81
Dependent Claim
13 words
An electrical circuit as described in claim 70, wherein said alloy includes fluorine.
Claim 82
Dependent Claim
13 words
An electrical circuit as described in claim 69, wherein said alloy includes germanium.
Claim 83
Dependent Claim
16 words
An electrical circuit as described in claim 69, wherein said alloy includes both silicon and germanium.
Claim 84
Dependent Claim
60 words
An electrical circuit as described in claim 68 wherein said first diode includes a first layer of deposited semiconductor material of a first conductivity type, a second layer of deposited semiconductor material of a relatively intrinsic type which contacts said first layer, and a third layer of deposited semiconductor material of a second conductivity type which contacts said second layer.
Claim 85
Dependent Claim
63 words
An electrical circuit as described in claim 75, wherein the other of said back-to-back diodes includes a fourth layer of deposited semiconductor material of said first conductivity type, a fifth layer of deposited semiconductor material of a relatively intrinsic type which contacts said fourth layer, and a sixth layer of deposited semiconductor material of said second conductivity type which contacts said fifth layer.
Claim 86
Dependent Claim
53 words
An electrical circuit as described in claim 76, wherein the programmable device is formed on a substrate and the layers of deposited semiconductor material of said first diode are deposited over said substrate and the layers of deposited semiconductor material of said second diode are deposited over said layers of the first diode.
Claim 87
Dependent Claim
23 words
An electrical circuit as described in claim 77, wherein a layer of relatively conductive material is placed between said first and second diodes.
Claim 88
Dependent Claim
16 words
An electrical circuit as described in claim 78, wherein said relatively conductive material is a metal.
Claim 89
Dependent Claim
37 words
An electrical circuit as described in claim 78, further including conductive means connected to said relatively conductive material located between said first and second diodes for supplying a programming voltage and current to said relatively conductive material.
Claim 90
Dependent Claim
58 words
An electrical circuit as described in claim 68, wherein said first diode includes a portion of metal and said layer of semiconductor material forms a rectifying semiconductor junction with said portion of metal so as to provide said relatively high impedance in said first direction along said series and a relatively low impedance in said second, opposite, direction.
Claim 91
Dependent Claim
59 words
An electrical circuit as described in claim 81, wherein said other back-to-back diode includes an additional portion of metal and a layer of deposited semiconductor material which forms a rectifying semiconductor junction with said additional portion of metal so as to provide said relatively high impedance in said second direction and a relatively low impedance in said first direction.
Claim 92
Dependent Claim
50 words
An electrical circuit as described in claim 82, wherein the programmable device is formed on a substrate and the deposited semiconductor material of said first diode is deposited over said substrate and the deposited semiconductor material of said second diode is deposited over said semiconductor material of said first diode.
Claim 93
Dependent Claim
27 words
An electrical circuit as described in claim 83, wherein a layer of relatively conductive material is placed between said first and second diodes of said programmable device.
Claim 94
Dependent Claim
34 words
An electrical circuit as described in claim 84, wherein said layer of relatively conductive material is a metal which forms said rectifying junctions with the semiconductor material of both said first and second diodes.
Claim 95
Dependent Claim
37 words
An electrical circuit as described in claim 84, further including conductive means connected to said relatively conductive material located between said first and second diodes for supplying a programming voltage and current to said relatively conductive material.
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| 3.5 Years (Year 4) | 1990-02-23 | 1990-08-25 | 1991-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-23 | 1994-08-25 | 1995-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-23 | 1998-08-25 | 1999-02-24 | $7700.00 | Window Closed / Lapsed |