US4238803A
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US
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Information recording methods using lasers
Assignee: Hitachi Ltd
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Filing: 1977-09-01
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Granted: 1980-12-09
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Expires: 1997-09-01
Abstract
Abstract A thin film is formed on a substrate, which film is made of a substantially amorphous chalcogenide having a composition of AsxxTeyxSezxGg, where G represents at least an element selected from a group consisting of S, In, Tl, Sn, Pb and Ge, and where 10 at %</=x</=25 at %, 50 at %</=y</=88 at %, 0 at %</=z</=40 at % and 0 at %</=g</=10 at %, and that x+y+z+g=100 and z+g NOTEQUAL 0. A laser beam is projected onto the thin film to form in it recesses representing information carried by the laser beam. The information recorded in the thin film exhibits a high signal-to-noise ratio and a high gamma characteristic. Besides, the recorded information is scarcely subjected to deterioration independently from time elapse.
Inventors
- 👤 Motoyasu Terao
- 👤 Seiji Yonezawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:05
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/705; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/242; G11B7/243; G11C; G11C13/00; G11C13/04; G11C13/048; G11B2007/24302; G11B2007/24306; G11B2007/2431; G11B2007/24312; G11B2007/24314; G11B2007/24316; G11B2007/24318; G11B2007/24324; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
147 words
A method of recording information in at least one thin film formed on a predetermined substrate by irradiating said at least one thin film with a laser ray beam in accordance with said information to form in said at least one thin film holes or recesses, said irradiating being sufficient to heat said at least one thin film to be softened and displaced or evaporated, said holes or recesses representing said information, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·G g , where G represents at least one element selected from a group consisting of S, In, Tl, Sn, Pb and Ge, and where 10 at %≦x≦25 at %, 50 at %≦y≦88 at %, 0 at %≦z≦40 at % and 0 at %≦g≦10 at %, and that x+y+z+g=100 and z+g≠0.
Claim 2
Independent Claim
147 words
A method of recording information in at least one thin film formed on a predetermined substrate by irradiating said at least one thin film with a laser ray beam in accordance with said information to form in said at least one thin film holes or recesses, said irradiating being sufficient to heat said at least one thin film to be softened and displaced or evaporated, said holes or recesses representing said information, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·G g , where G represents at least one element selected from a group consisting of S, In, Tl, Sn, Pb and Ge, and where 10 at %≦x≦25 at %, 50 at %≦y≦88 at %, 0 at %≦z≦40 at % and 0 at %≦g≦10 at %, and that x+y+z+g=100 and z+g≠0.
Claim 3
Dependent Claim
27 words
An information recording method according to claim 1, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 4
Dependent Claim
27 words
An information recording method according to claim 1, wherein thickness of said at least one thin film is in a range of 300 A to 600 A.
Claim 5
Dependent Claim
68 words
An information recording method according to claim 1, wherein thickness of said at least one thin film is in a range of 350 A to 480 A and wherein said laser beam is so projected onto said at least one thin film that energy level on the surface of said at least one thin film is in a range of 6.0 mJ/cm 2 to 24.0 mJ/cm 2 .
Claim 6
Dependent Claim
21 words
An information recording method according to claim 4, wherein an argon laser is used as a source of said laser beam.
Claim 7
Dependent Claim
15 words
An information recording method according to claim 1, wherein said substrate is formed of glass.
Claim 8
Dependent Claim
81 words
An information recording method according to claim 1, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·G g , where G represents at least one element selected from a group consisting of S, In, Tl, Sn, Pb and Ge, and where 10 at %≦x≦25 at %, 50 at %≦y≦88 at %, 0 at %≦z≦40 at % and 2 at %≦g≦10 at % and that x+y+z+g=100.
Claim 9
Dependent Claim
27 words
An information recording method according to claim 7, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 10
Dependent Claim
27 words
An information recording method according to claim 7, wherein thickness of said at least one thin film is in a range of 300 A to 600 A.
Claim 11
Dependent Claim
68 words
An information recording method according to claim 9, wherein thickness of said at least one thin film is in a range of 350 A to 480 A and wherein said laser beam is so projected onto said at least one thin film that energy level on the surface of said at least one thin film is in a range of 6.0 mJ/cm 2 to 24.0 mJ/cm 2 .
Claim 12
Dependent Claim
46 words
An information recording method according to claim 1, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·, where 10 at.%≦x≦25 at.%, 50 at.%≦y≦88 at.% and 0 at.%<z≦40 at.%, and x+y+z=100.
Claim 13
Dependent Claim
27 words
An information recording method according to claim 11, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 14
Dependent Claim
27 words
An information recording method according to claim 11, wherein thickness of said at least one thin film is in a range of 300 A to 600 A.
Claim 15
Dependent Claim
68 words
An information recording method according to claim 11, wherein thickness of said at least one thin film is in a range of 350 A to 480 A and wherein said laser beam is so projected onto said at least one thin film that energy level on the surface of said at least one thin film is in a range of 6.0 mJ/cm 2 to 24.0 mJ/cm 2 .
Claim 16
Dependent Claim
54 words
An information recording method according to claim 1, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·Ge g , where 10 at.%≦x≦25 at.%, 50 at.%≦y≦88 at.%, 0 at.%≦z≦40 at.% and 0 at.%≦g≦10 at.%, and that x+y+z+g=100 and z+g≠0.
Claim 17
Dependent Claim
27 words
An information recording method according to claim 15, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 18
Dependent Claim
27 words
An information recording method according to claim 15, wherein thickness of said at least one thin film is in a range of 300 A to 600 A.
Claim 19
Dependent Claim
67 words
An information recording method according to claim 15, wherein thickness of said at least one thin film is in a range of 350 A to 480 A, and wherein said laser beam is so projected onto said at least one thin film that energy level on the surface of said at least one film is in a range of 6.0 mJ/cm 2 to 24.0 mJ/cm 2 .
Claim 20
Dependent Claim
45 words
An information recording method according to claim 1, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Ge g , where 10 at.%≦x≦25 at.%≦y≦88 at.% and 0 at.%<g≦10 at.% and that x+y+g=100.
Claim 21
Dependent Claim
27 words
An information recording method according to claim 19, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 22
Dependent Claim
27 words
An information recording method according to claim 19, wherein thickness of said at least one thin film is in a range of 300 A to 600 A.
Claim 23
Dependent Claim
68 words
An information recording method according to claim 19, wherein thickness of said at least one thin film is in a range of 350 A to 480 A and wherein said laser beam is so projected onto said at least one thin film that energy level on the surface of said at least one thin film is in a range of 6.0 mJ/cm 2 to 24.0 mJ/cm 2 .
Claim 24
Dependent Claim
47 words
An information recording method according to claim 1, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Ge g , where 10 at.%≦x≦25 at.%, 50 at.%≦y≦88 at.% and 2 at.%≦g≦10 at.% and that x+y+g=100.
Claim 25
Dependent Claim
27 words
An information recording method according to claim 23, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 26
Dependent Claim
27 words
An information recording method according to claim 23, wherein thickness of said at least one thin film is in a range of 300 A to 600 A.
Claim 27
Dependent Claim
68 words
An information recording method according to claim 23, wherein thickness of said at least one thin film is in a range of 350 A to 480 A and wherein said laser beam is so projected into said at least one thin film that energy level on the surface of said at least one thin film is in a range of 6.0 mJ/cm 2 to 24.0 mJ/cm 2 .
Claim 28
Dependent Claim
24 words
An information recording method according to claim 1, wherein an intermediate layer is positioned between said at least one thin film and said substrate.
Claim 29
Dependent Claim
25 words
An information recording method according to claim 1, wherein a surface protection layer is positioned on the surface of said at least one thin film.
Claim 30
Dependent Claim
58 words
An information recording method according to claim 28, wherein said surface protection layer is selected from the group of materials consisting of amorphous materials of Sb-S-Ge series, Se-S-Ge series, Te-S-Ge series, Se-Ge series or S-Ge series, containing more than 65 at.% of S and more than 20 at.% of Ge or As-S series, As-S-Sb series and As-S-Se series.
Claim 31
Independent Claim
170 words
A method of recording information in at least one thin film on a predetermined substrate by irradiating said at least one thin film with a laser ray beam in accordance with said information to form in said at least one thin film holes or recesses, said irradiating being sufficient to heat said at least one thin film to be softened and displaced or evaporated, said holes or recesses representing said information, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·G g ·D d , where G represents at least one element selected from the group consisting of S, In, Tl, Sn, Pb and Ge, and D is selected from the group consisting of halogens, Si, P, Ag, Cu, Zn, Cd, Hg, Al, Ga, Sb, Bi, Mn, Fe, Co, Ni, Ce, V, Nb and Cr, and where 10 at.%≦x≦25 at.%, 50 at.%≦y≦88 at.%, 0 at.%≦z≦40 at.%, 0 at.%≦g≦10 at.%, 0 at.%<d≦10 at.%, x+y+z+g+d=100 and z+g≠0.
Claim 32
Independent Claim
170 words
A method of recording information in at least one thin film on a predetermined substrate by irradiating said at least one thin film with a laser ray beam in accordance with said information to form in said at least one thin film holes or recesses, said irradiating being sufficient to heat said at least one thin film to be softened and displaced or evaporated, said holes or recesses representing said information, wherein said at least one thin film is made of a substantially amorphous chalcogenide having a composition of As x ·Te y ·Se z ·G g ·D d , where G represents at least one element selected from the group consisting of S, In, Tl, Sn, Pb and Ge, and D is selected from the group consisting of halogens, Si, P, Ag, Cu, Zn, Cd, Hg, Al, Ga, Sb, Bi, Mn, Fe, Co, Ni, Ce, V, Nb and Cr, and where 10 at.%≦x≦25 at.%, 50 at.%≦y≦88 at.%, 0 at.%≦z≦40 at.%, 0 at.%≦g≦10 at.%, 0 at.%<d≦10 at.%, x+y+z+g+d=100 and z+g≠0.
Claim 33
Dependent Claim
27 words
An information recording method according to claim 30, wherein thickness of said at least one thin film is in a range of 200 A to 1000 A.
Claim 34
Dependent Claim
12 words
An information recording method according to claim 31, wherein 0 at.%<d≦5 at%.
Claim 35
Dependent Claim
12 words
An information recording method according to claim 30, wherein 0 at.%<d≦5 at.%.
Claim 36
Dependent Claim
25 words
An information recording method according to claim 1, wherein said irradiating acts to form directly in said at least one thin film holes or recesses.
Claim 37
Dependent Claim
25 words
An information recording method according to claim 30, wherein said irradiating acts to form directly in said at least one thin film holes or recesses.
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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) | 1983-12-09 | 1984-06-09 | 1984-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-09 | 1988-06-09 | 1988-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-09 | 1992-06-09 | 1992-12-09 | $7700.00 | Window Closed / Lapsed |