Image display

Abstract

It is an object of the present invention to provide an image display using a thin film electronic source having a structure for separating picture elements in a self-alignment manner. The structure of bus wiring (scanning line) for powering the electronic source is formed by a stacked structure including a lower layer 17 made of an alloy of CrMo, an intermediate layer 18 made of Al or an alloy of Al, and an upper layer 19 made of Cr, from a cathode substrate 10. The CrMo alloy in the lower layer 17 includes 30 wt % or more of Mo. Such a stacked structure can be used to process one side of the lower layer 17 to form an undercut relative to the intermediate layer 18. The undercut serves as a picture element separating structure in sputtering of an upper electrode 13 of the electronic source and achieves picture element separation in a self-alignment manner.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the structure of an MIM electronic source and its operation principles;

FIG. 2 is a plan view schematically showing an image display using the MIM electronic source according to the present invention;

FIG. 3 shows a manufacture step of the MIM electronic source;

FIG. 4 shows a manufacture step of the MIM electronic source subsequent to FIG. 3;

FIG. 5 shows a manufacture step of the MIM electronic source subsequent to FIG. 4;

FIG. 6 shows a manufacture step of the MIM electronic source subsequent to FIG. 5;

FIG. 7 shows a manufacture step of the MIM electronic source subsequent to FIG. 6;

FIG. 8 shows a manufacture step of the MIM electronic source subsequent to FIG. 7;

FIG. 9 shows a manufacture step of the MIM electronic source subsequent to FIG. 8;

FIG. 10 shows a manufacture step of the MIM electronic source subsequent to FIG. 9;

FIG. 11 shows a manufacture step of the MIM electronic source subsequent to FIG. 10;

FIG. 12 shows a manufacture step of the MIM electronic source subsequent to FIG. 11;

FIG. 13 shows a manufacture step of the MIM electronic source subsequent to FIG. 12;

FIG. 14 is a schematic diagram for explaining the method of forming a picture element separating structure;

FIG. 15 shows the relationship between the etching rate ratio of CrMo/Cr and the content of Mo;

FIG. 16 shows the relationship between the etching rate of CrMo and the content of Mo;

FIG. 17 shows another manufacture step of the MIM electronic source subsequent to FIG. 8;

FIG. 18 shows a manufacture step of the MIM electronic source subsequent to FIG. 17;

FIG. 19 shows a manufacture step of the MIM electronic source subsequent to FIG. 18;

FIG. 20 shows a manufacture step of the MIM electronic source subsequent to FIG. 19;

FIG. 21 shows a manufacture step of the MIM electronic source subsequent to FIG. 20;

FIG. 22 shows the relationship between the content of Cr of CrMo and the etching rate ratio of CrMo/Al;

FIG. 23 shows the relationship between the content of Cr of CrMo and the etching rate of CrMo;

FIG. 24 shows the relationship between the content of Ni of an alloy of CrMoNi and the thickness of a surface oxidation film (oxidation resistance); and

FIG. 25 is a section view showing the alloy of CrMoNi (SEM photograph).

Claims

1. An image display comprising: a lower electrode;an upper electrode;an electron accelerating layer sandwiched between the lower electrode and the upper electrode;a display panel formed of a cathode substrate including an array of thin film electronic sources which emit electrons from the side of the upper electrode in response to a voltage applied between the lower electrode and the upper electrode, and a fluorescent surface substrate having a fluorescent material formed thereon to emit light through excitation by the electrons;a driving circuit driving the lower electrode and the upper electrode; andan upper bus electrode powering the upper electrode and formed of three or more stacked films formed by sandwiching aluminum or an alloy of aluminum between a layer made of chromium and a layer of an alloy of chromium and molybdenum, the alloy of chromium and molybdenum including 30 wt % or more of molybdenum.

2. The image display according to claim 1, wherein the layer of the alloy of chromium and molybdenum is protruded from the aluminum or the alloy of aluminum to connect to the upper electrode on one side of the upper bus electrode, and forms an undercut relative to the aluminum or the alloy of aluminum to provide separation of the upper electrode for each upper bus electrode on the other side.

3. The image display according to claim 1, wherein the layer of the alloy of chromium and molybdenum is connected to the upper electrode in a flat contact portion protruded from the aluminum or the alloy of aluminum on one side of the upper bus electrode, and forms an undercut relative to the aluminum or the alloy of aluminum to provide separation of the upper electrode for each upper bus electrode on the other side.

4. The image display according to claim 1, wherein the layer of the alloy of chromium and molybdenum includes 60 wt % or lower of molybdenum.

5. The image display according to claim 1, wherein the upper bus electrode is used as a scanning line in matrix driving.

6. An image display comprising: a lower electrode;an upper electrode;an electron accelerating layer sandwiched between the lower electrode and the upper electrode;a display panel formed of a cathode substrate including an array of thin film electronic sources which emit electrons from the side of the upper electrode in response to a voltage applied between the lower electrode and the upper electrode, and a fluorescent surface substrate having a fluorescent material formed thereon to emit light through excitation by the electrons;a driving circuit driving the lower electrode and the upper electrode; andan upper bus electrode powering the upper electrode and formed of three or more stacked films formed by sandwiching aluminum or an alloy of aluminum between a layer made of chromium and an alloy of chromium and molybdenum, the alloy of chromium and molybdenum including not less than 2.5 wt % to not more than 8 wt % of chromium.

7. The image display according to claim 6, wherein the layer of the alloy of chromium and molybdenum is protruded from the aluminum or the alloy of aluminum to connect to the upper electrode on one side of the upper bus electrode, and forms an undercut relative to the aluminum or the alloy of aluminum to provide separation of the upper electrode for each upper bus electrode on the other side.

8. The image display according to claim 6, wherein the layer of the alloy of chromium and molybdenum is connected to the upper electrode in a tapered shape protruded from the aluminum or the alloy of aluminum in a tapered shape on one side of the upper bus electrode, and forms an undercut relative to the aluminum or the alloy of aluminum to provide separation of the upper electrode for each upper bus electrode on the other side.

9. The image display according to claim 6, wherein the upper bus electrode is used as a scanning line in matrix driving.

10. An image display comprising: a lower electrode;an upper electrode;an electron accelerating layer sandwiched between the lower electrode and the upper electrode;a display panel formed of a cathode substrate including an array of thin film electronic sources which emit electrons from the side of the upper electrode in response to a voltage applied between the lower electrode and the upper electrode, and a fluorescent surface substrate having a fluorescent material formed thereon to emit light through excitation by the electrons;a driving circuit driving the lower electrode and the upper electrode; andan upper bus electrode powering the upper electrode and formed of three or more stacked films formed by sandwiching aluminum or an alloy of aluminum between a layer made of chromium and an alloy of chromium, molybdenum, and nickel, the alloy of chromium, molybdenum, and nickel including not less than 2.5 wt % to not more than 8 wt % of chromium and 25 wt % or more of nickel.

11. The image display according to claim 10, wherein the layer of the alloy of chromium and molybdenum is protruded from the aluminum or the alloy of aluminum to connect to the upper electrode on one side of the upper bus electrode, and forms an undercut relative to the aluminum or the alloy of aluminum to provide separation of the upper electrode for each upper bus electrode on the other side.

12. The image display according to claim 10, wherein the layer of the alloy of chromium and molybdenum is connected to the upper electrode in a tapered shape protruded from the aluminum or the alloy of aluminum in a tapered shape on one side of the upper bus electrode, and forms an undercut relative to the aluminum or the alloy of aluminum to provide separation of the upper electrode for each upper bus electrode on the other side.

13. The image display according to claim 10, wherein the upper bus electrode is used as a scanning line in matrix driving.