Light-sensitive film

• US 4,289,822 A
• Filed: 06/15/1979
• Issued: 09/15/1981
• Est. Priority Date: 06/26/1978
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Katayama, Yoshifumi, Shimada, Toshikazu, Komatsubara, Kiichi F.
• Primary Examiner(s): Robinson, Ellis P.
• Application Number:
  US06/048,740
• Time in Patent Office: 823 Days
• Field of Search: 428/446, 428/913, 428/411, 428/450, 428/539, 428/212, 428/336, 427/74, 427/93, 427/95, 204/192 P, 204/192 S
• US Class Current: 428/212
• CPC Class Codes: G03G 5/0433 all layers being inorganic
• CPC Class Codes: G03G 5/082 and not being incorporated in a bonding material, e.g. vacuum deposited
• CPC Class Codes: G03G 5/08235 comprising three or four silicon-based layers
• CPC Class Codes: G03G 5/08242 at least one with varying composition
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]

Abstract

A photoconductive material comprising an amorphous substance whose indispensable constituent elements are silicon, carbon and hydrogen is disclosed. The photoconductive material preferably has a structure expressed by [Si_1-x C_x ]_1-y [H]_y where 0.02≦x≦0.3 and 0.02≦y≦0.3. Up to 40% of the carbon can be substituted by germanium. The peak of response can be established for light of any desired wavelength between approximately 5,600 A-4,500 A. This photoconductive material is particularly useful when applied to a light-sensitive film which is operated in the storage mode. The light-sensitive film includes the photoconductive material in a region in which pairs of free electrons and positive holes are created upon incidence of light.

Claims

1. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0≦

x≦

0.3 and 0.02≦

y≦

0.3, whereby said light-sensitive film exhibits photoconductive characteristics.

2. An article according to claim 1, wherein 0.02≦

x≦

0.3 and 0.02≦

y≦

0.3.

3. An article according to claim 1, wherein said amorphous material has a dark resistivity of at least 10¹⁰ Ω

·

cm.

4. An article according to claim 2, wherein said amorphous material has a dark resistivity of at least 10¹⁰ Ω

·

cm.

5. An article according to claim 1, wherein the at least one layer which is made of the amorphous photoconductive material is at least 100 nm thick.

6. An article according to claim 5, wherein said substrate comprises a faceplate having thereon a light-transmitting conducting layer, with at least one photoconductive layer positioned on said light-transmitting conducting layer, and with the amorphous photoconductive material layer adjacent said at least one photoconductive layer.

7. An article according to claim 1 or claim 5, wherein said amorphous photoconductive material has at least one impurity element incorporated therein for providing a desired conductivity type material.

21. An article according to claim 2, wherein said amorphous photoconductive material has a dark resistivity of at least 10¹⁰ Ω

·

cm.

22. An article according to claim 2, wherein said amorphous photoconductive material has incorporated therein at least one impurity element for providing a desired conductivity type material.

23. An article according to claim 1, wherein said light-sensitive film is constructed of at least two layers of at least one photoconductive material, with one of said at least two layers made of said amorphous photoconductive material, and with the amorphous photoconductive material layer having a higher resistivity than the other photoconductive layers of said light-sensitive film, whereby the amorphous photoconductive material layer can act to store charge patterns formed in the light-sensitive film.

8. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0≦

x≦

0.3 and 0.02≦

y≦

0.3, whereby said light sensitive film exhibits photoconductive characteristics and wherein an n-type oxide layer is positioned between said light-sensitive film and said substrate, whereby injection of positive holes from the substrate into the light-sensitive film is prevented.

9. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

y≦

0.3, and is at least 100 nm thick, whereby said light-sensitive film exhibits photoconductive characteristics and wherein an n-type oxide layer is positioned between said light-sensitive film and said substrate, whereby injection of positive holes from the substrate into the light-sensitive film is prevented.

10. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

y≦

0.3, and is at least 100 nm thick, whereby said light-sensitive film exhibits photoconductive characteristics, wherein said substrate comprises a faceplate having thereon a light-transmitting conducting layer, with at least one photoconductive layer positioned on said light-transmitting conducting layer, and with the amorphous photoconductive material layer adjacent said at least one photoconductive layer, and wherein an n-type oxide layer is positioned between said light-sensitive film and said substrate, whereby injection of positive holes from the substrate into the light-sensitive film is prevented.

11. An article according to claim 8, 9 or 10, wherein the n-type oxide layer is made of a material selected from the group consisting of cerium oxide, tungsten oxide, niobium oxide, germanium oxide and molybdenum oxide.

12. An article according to claim 11, whereby said n-type oxide layer has a thickness of 5 nm to 100 nm.

17. An article according to claim 8, 9 or 10 wherein a layer of antimony trisulfide is positioned on top of the light-sensitive film.

18. An article according to claim 17, wherein the antimony trisulfide layer has a thickness of 10 nm to 1 μ

m.

13. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

y≦

0.3, whereby said light-sensitive film exhibits photoconductive characteristics and wherein a layer of antimony trisulfide is positioned on top of the light-sensitive film.

16. An article according to claim 13, 14 or 15 wherein the antimony trisulfide layer has a thickness of 10 nm to 1 μ

m.

14. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1- C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

y≦

0.3, whereby said light-sensitive film exhibits photoconductive characteristics and wherein a layer of antimony trisulfide is positioned on top of the light-sensitive film and is at least 100 nm thick.

15. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

Y≦

0.3, whereby said light-sensitive film exhibits photoconductive characteristics wherein said substrate comprises a faceplate having thereon a light-transmitting conducting layer, with at least one photoconductive layer positioned on said light-transmitting conducting layer, and with the amorphous photoconductive material layer adjacent said at least one photoconductive layer, and wherein a layer of antimony trisulfide is positioned on top of the light-sensitive film and is at least 100 nm thick.

19. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

y≦

0.3, whereby said light-sensitive film exhibits photoconductive characteristics and wherein the at least one layer of the amorphous photoconductor material has a continuously varying composition with x varying from a high value of x 0.3 to a lower value less than said high value but greater than 0, from one surface to the opposite surface of said at least one layer of the amorphous photoconductive material, with a layer of (si)_1-y (H)_y adjacent the surface of the amorphous photoconductive material having the lower value of x.

20. An article according to claim 19, wherein the surface of the at least one layer of the amorphous photoconductive material where x has said high value is adjacent said substrate.

24. An article comprising a light-sensitive film constructed of at least a single layer of at least one photoconductive material on a substrate, wherein at least one layer of said at least a single layer is made of an amorphous photoconductive material whose composition is expressed by a formula [Si_1-x C_x ]_1-y [H]_y where 0<

x≦

0.3 and 0.02≦

y≦

0.3, with up to 40% of the carbon in the amorphous photoconductive material being replaced by germanium, whereby said light-sensitive film exhibits photoconductive characteristics.

25. An article according to claim 24, wherein said amorphous photoconductive material has a dark resistivity of at least 10¹⁰ Ω

·

cm.

26. An article according to claim 24, wherein said amorphous photoconductive material has at least one impurity element incorporated therein for providing a desired conductivity type material.