JP2001307664A - Cathode device and its manufacturing method, and field- emission type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode device capable of preventing all emitters from breaking simultaneously in the case that discharging is generated in the emitter. SOLUTION: The cathode device is provided on a glass substrate 21 and has a group of emitters 23 to 25, each of which has a height difference by a specified amount based on the surface of the glass substrate 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a cathode device, a method of manufacturing the same, and a field emission display device.

[0002]

2. Description of the Related Art Spindt methods, methods for manufacturing an emitter array (cathode device) of a field emission display device, and the like.
There were a transfer molding method and a printing method. The emitters of the emitter array manufactured by these methods had a substantially uniform shape and size over the entire screen.

[0003]

The field emission display device using the above-mentioned conventional emitter array has the following problems. That is, when a discharge occurs between the emitter and the gate or between the emitter and the anode, the emitter is destroyed. In the Spindt method, the transfer molding method, and the printing method, since the shape and dimensions of the emitters are almost uniform, it is not possible to actively control the electron emission characteristics, and control the probability of discharge occurring in each emitter. Was impossible. Therefore, when a discharge is generated in the emitter constituting one pixel, a discharge is similarly generated in the other emitters, and as a result, there is a possibility that all of them are destroyed simultaneously by a single discharge. For this reason, there is a possibility that the function of the entire apparatus cannot be maintained.

On the other hand, as a configuration of a device capable of preventing the destruction of the emitter even when a discharge occurs between the emitter and the gate or between the emitter and the anode, a method of arranging a ballast resistor on each emitter is known. However, this has made the apparatus complicated.

Accordingly, the present invention is directed to an emitter array used in a field emission display device or the like, in which a discharge occurs between an emitter and a gate or between an emitter and an anode, all the emitters are destroyed at the same time. It is an object of the present invention to provide an emitter array, a method of manufacturing the same, and a field emission display device, which can prevent the occurrence of the problem and maintain the function of the entire device.

[0006]

In order to solve the above problems and to achieve the object, an emitter array, a method of manufacturing the same, and a field emission display device of the present invention are configured as follows.

(1) It is characterized by comprising a substrate, and at least one set of emitter groups provided on the substrate and having different heights from the substrate surface by a predetermined amount.

(2) It is characterized by comprising the cathode device described in the above (1).

(3) In a method of manufacturing a cathode device having a plurality of emitter groups having different heights on a workpiece, the cathode workpiece is cut to form the emitter shape by cutting the workpiece. It is characterized by having a process.

(4) A method for manufacturing a cathode device having a plurality of emitter groups having different heights, the method comprising:
By cutting the master material, a cutting step of shaping the emitter shape to form a master, a plating tool forming step of forming a plating tool by the master, and pressing the plating tool against a mold material, thereby forming a mold. And a mold forming step of forming

(5) The method for manufacturing a cathode device according to (4), wherein the mold forming step includes a step of pressing the plating tool against the mold material a plurality of times while shifting the position. It is characterized by.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In these figures, arrows XYZ indicate three directions orthogonal to each other.

FIG. 1 is a sectional view showing a main part of a field emission display device 10 according to a first embodiment of the present invention. The field emission display device 10 includes an emitter array 20, a gate electrode 30 disposed on the emitter array 20 via an insulator 31, and a display unit 40 disposed opposite the gate electrode 30. The emitter array 20 includes a glass substrate 21, a cathode 22 provided on the substrate 21, and a plurality of emitter groups 23 to 25 provided on the cathode 22.

The shape and dimensions of the emitter are as follows.
1 to 50 μm, apex angle θ = about 70 °, height H = 1 to 50 μm
m is a three-dimensional pyramid formed by translating a pyramid of m or a quadrangular pyramid in a direction parallel to the bottom surface, and is arranged in a lattice with a gap M = 1 to 50 μm.

The display unit 40 includes a glass substrate 41, an anode 42 formed on the lower surface of the glass substrate 41, and a phosphor 43 attached to the anode 42.

FIG. 2 is a top view and a side view of one pixel when such an emitter array 20 is manufactured by cutting, and FIG. 3 is a view of one pixel when manufactured by pressing plastic working. FIG. 2 shows a top view and a side view of a pixel.

As shown in FIGS. 2 and 3, the emitter group 2
3 has a side length L1 = 10.0 μm,
The apex angle θ1 = 70 °, the height H1 = 7.0 μm, the emitter 24a of the emitter group 24 has one side length L2 = 5.0 μm,
Apex angle θ2 = 70 °, height H2 = 3.5 μm, emitter 25a of emitter group 25 has one side length L3 = 2.5 μm,
The apex angle θ3 = 70 ° and the height H3 = 1.7 μm. The gap M is 10.0 μm.

The emitter array 20 constructed as described above
In the case of the above, when a discharge occurs between the emitters 23a to 25a and the cathode 22 or between the emitters 23a to 25a and the anode 40, the discharge has the highest height L1 =
It occurs selectively to the 7.0 μm emitter 23a.

Therefore, until all the emitters 23a in one pixel are destroyed, the emitters 24a and 25a are not involved in the discharge, and it is possible to prevent all the emitters 23a to 25a in one pixel from being destroyed at the same time. be able to. Although the number of emitters in one pixel decreases due to the destruction of the emitter 23a, the required number of emitters contributing to field emission in one pixel is sufficient, and the function of the device is maintained.

FIG. 4 shows a processing apparatus 100 for manufacturing the emitter array 20 and the emitter array master Q of the field emission display device of the present invention by cutting. The workpiece G is formed of a material such as oxygen-free copper, aluminum, indium, an electroless Ni plating layer, and Ni plating.

The processing apparatus 100 has a gantry 101. A Z-axis table 102 is provided on the gantry 101, and a C-axis 103 for positioning in the Z-axis direction is supported by the Z-axis table 102. In addition, C axis 1
Numeral 03 is composed of an air spindle, on which the workpiece G is mounted and which rotates and positions the workpiece G.

An X-axis table 104 is provided on the gantry 101, and a Y-axis table 105 for positioning in the X-axis direction is supported by the X-axis table 104. Further, the Y-axis table 105 includes a Y-axis table 1
05 is the tool spindle 10 for positioning in the Y-axis direction
6 are provided. Note that the tool spindle 106 is formed of an air spindle, and a diamond tool 107 serving as a tool is mounted on the tool spindle.

The Z-axis table 102 has a stroke of 10 mm or more, a straightness of 0.1 μm or less, and a squareness of 0.1 μm.
m or less, the positioning accuracy is 10 nm or less, and the C-axis 103
Indicates the amount of rotational runout of 0.05 μm or less in the radial direction, the amount of axial runout of 0.05 μm or less, and the positioning accuracy of 1 × 10 −5 deg.
It is as follows.

The X-axis table 104 has a stroke of 800 mm or more, a straightness of 0.8 μm or less, and a squareness of 0.8 μm.
μm or less, positioning accuracy 10 nm or less, Y-axis table 1
05 is stroke 800mm or more, straightness 0.8μm
Hereinafter, the squareness is 0.8 μm or less, the positioning accuracy is 10 nm or less, and the tool spindle 106 has a radial rotational runout of 0.05 μm.
Hereinafter, the axial rotation runout amount is 0.05 μm or less.

FIG. 5 shows the geometric relationship of the cutting process. The diamond cutting tool rake face J has a flat V-shaped tip, and moves along an arc locus J1 about the rotation axis of the tool spindle 106. This arc locus J1
Is moved by the X-axis table 104 of the processing apparatus 100 to process one V-groove G1 having a flat tip. One V
After the groove G1 is machined, the Y-axis table 105 moves the pick feed P in the Y direction to machine a similar V-groove G1, leaving a triangular ridge N between the two grooves.
Here, P = the length Li of one side of the emitter + the gap M.

FIG. 6 shows triangular rows N1 to N3 having ternary heights H1, H2 and H3 formed on the entire surface of the workpiece by repeating the above. Thereafter, the workpiece G is moved to C
By rotating by 90 ° by the shaft 103 and performing the same processing, only the intersection of the triangular ridge N and the triangular ridge N is formed by translating the quadrangular pyramid Ω1 or the quadrangular pyramid Ω1 in a direction parallel to the bottom surface. An array of square pyramids Ω1 or solid Ω2 is formed on the entire surface of the workpiece G.

In this state, burrs may be formed on the ridge line of the quadrangular pyramid Ω1 due to the flow of the workpiece G.
By repeating the processing of the same tool path described above again, cutting is performed (zero cut), and burrs can be removed.

FIG. 7 shows a method of designing the diamond cutting tool 107. The cutting edge length W and the vertex angle φ of the diamond cutting tool are respectively the gap M of the emitter and the vertex angle θ.
be equivalent to.

The clearance angle α of the front cutting edge is the cutting edge height E of the diamond cutting tool, the turning radius R of the front cutting edge, the cutting depth D,
From the clearance angle γ between the flank surface of the front cutting edge and the cutting surface, α = 90 ° −tan ⁻¹ [E / (R ｛1-√ ｛1- (D /
R) 2｝｝)] + γ.

The lateral cutting edge clearance angle β is such that the cutting edge is # 2
The largest value is required at the position of 5, and from the bite vertex angle ψ, the front cutting edge turning radius R, the cutting depth D, the clearance angle γ between the front cutting edge flank surface and the cutting creation surface, β = √ ｛ 2 (D / R)-(D / R) 2｝ -sin (φ /
2) It is given by + γ.

FIG. 8 shows an example of a diamond tool 107 designed and manufactured. 8mm long, 8m wide
m, a single crystal diamond tip 109 is brazed to the tip of a cemented carbide shank 108 having a length of about 60 mm,
Each dimension is polished to the values described above. In addition, the clearance angle γ was set to γ = 3 ° in consideration of an error of diamond cutting. R = 60 mm, D = 10 μm, E = 2
mm, φ = 35 °, α, β≪γ, and α,
β can be ignored. The cutting edge of the cutting tool is polished so that the radius of curvature of the ridge is 0.1 μm or less.

FIG. 9 shows a method of setting the cutting conditions, in particular, the maximum cut thickness t and the cutting speed V. The maximum cutting thickness t is given by: t = F / S√ ｛2 (D / R) − (D / R) from the spindle speed S, the X-axis feed speed F, the front cutting edge turning radius R, and the cutting depth D. It is given by 2｝.

The cutting speed V is given by V = 2πRS from the spindle rotation speed S and the front cutting edge rotation radius R.

On the other hand, in order to obtain a tip radius of the emitter of <30 nm, the maximum cut-off thickness needs to be t ≦ 1 μm. The cutting speed V is V ≧ 1 × 10
It needs to be ² m / min. This condition
For ^{example, S = 2000min - 1, F} = 100mm / m
in, R = 60 mm and D = 0.010 mm.

FIG. 10 shows an emitter array 20 or an emitter array master Q of the field emission display device of the present invention.
1 shows a processing apparatus 110 for manufacturing a workpiece 1 by cutting.

The processing device 110 has a gantry 111. A C-axis 112 constituted by an air spindle is provided on the gantry 111, and a workpiece G is mounted on the C-axis 112 to rotate and position the workpiece G.

On the gantry 111, a Y-axis table 113 is provided, and an X-axis table 114 for positioning in the Y-axis direction is supported by the Y-axis table 113. Further, the X-axis table 114 includes an X-axis table 1
There is provided a Z-axis table 115 for positioning in the X-axis direction by. Further, a tool spindle 116 on which positioning in the Z-axis direction is performed by the Z-axis table 115 is mounted on the Z-axis table 115 in a state where rotational balance is maintained. A diamond tool 117 is mounted on the tool spindle 116, and the cutting edge of the tool is given a rotational motion of an arc locus.

The C-axis 112 has a radial rotational runout of 0.05 μm or less, an axial rotational runout of 0.05 μm or less, and a positioning accuracy of 1 × 10 −5 deg or less.

The Y-axis table 113 has a stroke of 800 mm or more, a straightness of 0.8 μm or less, and a squareness of 0.8 μm.
μm or less, positioning accuracy 10 nm or less, X-axis table 1
14 has a stroke of 800 mm or more and a straightness of 0.8 μm
Hereinafter, the squareness is 0.8 μm or less, the positioning accuracy is 10 nm or less, and the Z-axis table 115 has a stroke of 10 mm or more.
Straightness is 0.1 μm or less, squareness is 0.1 μm or less, and positioning accuracy is 10 nm or less. Also, the tool spindle 116 is
With the tool attached, the radial rotational runout is 0.05 μm or less, and the axial rotational runout is 0.05 μm or less.

FIG. 11 shows a processing apparatus 130 for manufacturing the emitter array mold U, the emitter master Q1, and the emitter mold T1 of the field emission display device of the present invention by pressing and plastic working.

The processing apparatus 130 has a gantry 131. A Z-axis table 132 is provided on the gantry 131, and a C-axis 133 for positioning in the Z-axis direction is supported by the Z-axis table 132. In addition, C axis 1
Reference numeral 33 denotes an air spindle, on which a workpiece G is mounted and which rotates and positions the workpiece G.

An X-axis table 134 is provided on the gantry 131, and a Y-axis table 135 for positioning in the X-axis direction is supported by the X-axis table 134. Further, the Y-axis table 135 includes the Y-axis table 1
The tool support 1 for positioning in the Y-axis direction by 35
36 are mounted. Note that a tool 137 for pressing and plastic working and a diamond bite 138 are mounted on the tool support portion 136.

The Z-axis table 132 has a stroke of 10 mm or more, a straightness of 0.1 μm or less, and a squareness of 0.1 μm.
m or less, the positioning accuracy is 10 nm or less, and the C-axis 133
Indicates the amount of rotational runout of 0.05 μm or less in the radial direction, the amount of axial runout of 0.05 μm or less, and the positioning accuracy of 1 × 10 −5 deg.
It is as follows.

The X-axis table 134 has a stroke of 800 mm or more, a straightness of 0.8 μm or less, and a squareness of 0.8 μm.
μm or less, positioning accuracy 10 nm or less, Y-axis table 1
35 has a stroke of 800 mm or more and a straightness of 0.8 μm
Hereinafter, the squareness is 0.8 μm or less, and the positioning accuracy is 10 nm or less.

The tool 137 is made of a diamond indenter K polished to the same pyramid shape as the emitter, or an electrolytic (or non-electrolytic) made based on an emitter master Q1 of about 1000 × 1000 array manufactured by cutting. Electrolysis) N
Electrolytic (or electroless) Ni manufactured using an i-plating tool Q3 or an emitter mold T1 of about 1000 × 1000 arrays manufactured by anisotropic etching of Si.
An electrolytic (or electroless) Ni-plating tool T2 manufactured using a plating tool T2 or an emitter mold T1 manufactured by pressing and plastic working with a diamond indenter K is used. Note that the diamond indenter K has a curvature radius of the ridge of 0.1.
It is assumed that it has been polished to μm or less.

FIG. 12 shows that the tool 137 is connected to the emitter master Q1.
1 shows a process of manufacturing using the method shown in FIG. Emitter master Q1 cut with oxygen-free copper, aluminum, indium, electrolytic (or electroless) Ni plating layer as workpiece G
An electrolytic (or electroless) Ni plating for primary transfer is applied thereon, and then separated to obtain an electrolytic (or electroless) Ni plating mold Q2. Next, place 2 on the electrolytic (or electroless) Ni plating mold Q2.
After performing electrolytic (or electroless) Ni plating for the next transfer, the resultant is peeled off to obtain an electrolytic (or electroless) Ni plating tool Q3.

FIG. 13 shows that the tool 137 is connected to the emitter mold T1.
1 shows a process of manufacturing using the method shown in FIG. Electrolytic (or electroless) Ni plating for primary transfer is performed on the emitter mold T1 and then peeled off.
An i-plating tool T2 is obtained.

FIG. 14 shows a working process of press plastic working. A workpiece G that can constitute the entire FED (Field Emission Display) screen processed to a flatness of 0.1 μm or less or the entire FED screen by tiling is placed on the Z-axis table 132 or the gantry 131 of the processing apparatus 130. Be attached.

The workpiece G is an oxygen-free copper, aluminum, indium, electrolytic (or electroless) Ni plating layer. The diamond indenter K or the tool 137 is mounted on the Z-axis table 132 or the Y-axis table 135 of the processing apparatus 130,
It is positioned at a predetermined position by the axis table 134 and the Y-axis table 135, and is pushed down to a depth corresponding to the emitter heights H1 to H3 by the Z-axis table 132, and the position is moved for a time (0 to 30 seconds) necessary for plastic deformation. Then, it is raised to the original position and the processing at the next processing point is repeated. The number of arrays in the entire FED screen is about 1500
0 × length about 8000, but the processing time by this method is
Assuming that the time required for one press plastic working is 60 seconds, {(15000/1000) × (8000/1000)} × 60 sec = 2 hours, and the emitter array mold U on the entire surface of the FED screen is processed in a very short time. Is possible. A bulge Ua due to plastic deformation of the mold material may be generated around the tool pressed by the pressing plastic working.

This swell Ua is determined by the Y-axis table 13
5 is used as a tool, a diamond cutting tool 138 for plane processing, which is detachably mounted near an electrolytic (or electroless) Ni plating tool on the tool 5, and the work is rotated by an air spindle of a C-axis 133 to make the surface bulge flat. It can be removed by cutting.

FIG. 15 shows a processing apparatus 140 for manufacturing the emitter array master U of the field emission type display apparatus of the present invention by pressing and forming. The processing device 140 includes a gantry 141. On the gantry 141, a Y-axis table 142 is provided, and the Y-axis table 142 supports an X-axis table 143 for positioning in the Y-axis direction. Further, the X-axis table 14
3 is provided with a Z-axis table 144 on which positioning in the X-axis direction is performed by the X-axis table 143. The Z-axis table 144 is provided with a tool support 145 for positioning in the Z-axis direction by the Z-axis table 144 and a plane processing tool spindle 146 having a rotation axis in the Z-axis direction. A diamond cutting tool 147 for plane machining is mounted on the tool spindle 146, and the cutting edge of the cutting tool is given a rotational motion of an arc trajectory. Tool support 145
, An electrolytic (or electroless) Ni plating tool 148 is attached.

The Y-axis table 142 has a stroke 800
mm or more, straightness 0.8 μm or less, squareness 0.8 μm or less, positioning accuracy 10 nm or less, X-axis table 143
Has a stroke of 800 mm or more, a straightness of 0.8 μm or less, a squareness of 0.8 μm or less, a positioning accuracy of 10 nm or less, and a Z-axis table 144 with a stroke of 10 mm or more.
Straightness is 0.1 μm or less, squareness is 0.1 μm or less, and positioning accuracy is 10 nm or less.

In the case of the processing device 140, after processing the emitter array mold U in the same manner as in FIG.
47 is rotated to remove bulges Ua on the material surface by plane milling.

FIG. 16 is an exploded view showing only the configuration of a portion corresponding to one pixel from the FED.

This FED is roughly divided into a cathode device 200 (200) disposed on the back side of the display device.
And the anode device 210 (2
10).

The cathode device 200 includes an emitter electrode 202
(Emitter shape 2) A substrate 201 formed by the above-described method, and a gate electrode laminated on the substrate via an insulating layer (not shown) and having an opening surrounding the sharpened tip of the emitter electrode 202 203.

Then, the gate electrode 20 is placed under a reduced pressure environment.
By applying a predetermined voltage between the emitter electrode 3 and the emitter electrode 202, electrons can be emitted from the tip of the emitter electrode 202. That is, the gate electrode 203 and the emitter electrode 202 are connected to a drive circuit (not shown),
Electrons can be emitted from any of the emitter electrodes 202 by matrix control.

On the other hand, the anode device 210 includes a light-transmitting substrate 211 made of glass or the like, and the cathode device 20 of the light-transmitting substrate 211.
The anode electrode 212 is formed of an ITO film or the like formed on the surface opposing 0, and the R, G, and B fluorescent films 213a, 213b, and 213c formed on the surface of the anode electrode 212. The anode electrode 212 is connected to a drive circuit (not shown).
When a predetermined voltage is applied between the light emitting device and the emitter electrode 202, electrons emitted from the emitter electrode 202 can be controlled.

As a result, electrons can collide with an arbitrary fluorescent film, whereby a desired image can be displayed through the translucent substrate 211.

It is needless to say that the present invention is not limited to the one applied to such an FED, but can be variously modified without changing the gist of the invention.

[0061]

According to the present invention, when a discharge occurs between the emitter and the gate or between the emitter and the anode, it is possible to prevent all the emitters from being destroyed at the same time, and to function as a whole device. It is possible to maintain

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a field emission display device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a main part of an emitter array incorporated in the field emission display device.

FIG. 3 is an explanatory diagram showing a main part of an emitter array incorporated in the field emission display device.

FIG. 4 is a perspective view showing a first example of a processing apparatus for manufacturing the emitter array.

FIG. 5 is an explanatory diagram showing a geometric relationship of cutting in the processing apparatus.

FIG. 6 is an explanatory diagram showing a geometric relationship of cutting in the processing apparatus.

FIG. 7 is an explanatory view showing a design of a diamond tool used in the processing apparatus.

FIG. 8 is an explanatory view showing the shape and dimensions of the diamond cutting tool.

FIG. 9 is an explanatory diagram showing a maximum cut-out thickness among geometrical relationships of cutting in the processing apparatus.

FIG. 10 is a perspective view showing a second example of the processing apparatus.

FIG. 11 is a perspective view showing a third example of the processing apparatus.

FIG. 12 is an explanatory view showing a step of manufacturing a Ni plating tool from an emitter master using the processing apparatus.

FIG. 13 is an explanatory view showing a step of manufacturing a Ni plating tool from an emitter mold manufactured by anisotropic etching using the processing apparatus.

FIG. 14 is an explanatory view showing a step of manufacturing an emitter array mold by the processing apparatus.

FIG. 15 is a perspective view showing a fourth example of the processing apparatus.

FIG. 16 is an exploded perspective view showing the FED.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Field emission display apparatus 20 ... Emitter array 30 ... Gate electrode 40 ... Display part 21 ... Glass substrate 22 ... Cathode 23-25 ... Emitter group 40 ... Display part 41 ... Glass substrate 42 ... Anode 100, 110, 130, 140 ... Processing equipment

Continued on the front page (72) Inventor Fujio Takahashi 33, Isoiso-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside Toshiba Production Technology Center (72) Inventor Takayuki Masunaga 33, Isoiso-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Stock Company Inside the Toshiba Production Technology Center (72) Inventor Satoshi Honda 33, Shinisogo-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Toshiba Production Technology Center (72) Inventor Masayuki Nakamoto 33 Shinisogo-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Address F-term in Toshiba Production Technology Center Co., Ltd. (reference) 5C031 DD17 5C036 EE19 EF01 EF06 EF08 EG02 EG12 EH04

Claims (5)

[Claims] 1. A cathode device comprising: a substrate; and at least one set of emitter groups provided on the substrate and having different heights with respect to the substrate surface by a predetermined amount. 2. A field emission display device comprising the cathode device according to claim 1. 3. A method of manufacturing a cathode device having a plurality of emitter groups having different heights on a workpiece, wherein the workpiece is cut to form the emitter shape by cutting the workpiece. A method for manufacturing a cathode device, comprising: 4. A method for manufacturing a cathode device having a plurality of emitter groups having different heights, comprising: a cutting step of shaving an emitter shape by cutting a master material to form a master. A cathode tool device, comprising: a plating tool forming step of forming a plating tool from the master; and a mold forming step of forming a mold by pressing the plating tool against a mold material. Method. 5. The method according to claim 4, wherein the mold forming step includes a step of pressing the plating tool against the mold material a plurality of times while shifting the position.