JPH09192864A - Manufacturing equipment and manufacture of surface conduction type electron emission element using laser beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a surface conduction type electron emission element which can be stably machined and is excellent in the yield by taking in and discriminating the image information on the surface of a work to detect the position of the work SOLUTION: A laser beam oscillator 1 which is the light source of the laser beam, and a high-speed shutter to turn ON/OFF the laser beam radiate the laser beam in the direction of a work 7 by a half mirror 3, and at the same time, the surface of the work 7 is observed through the half mirror 3. The work is relatively moved in the X, Y direction to the laser beam by a scanning mechanism 6. The image of the surface of the work 7 is taken in by an image take-in device 12. The image is discriminated by an image discriminating device 13. A computer 11 intensively controls the laser beam oscillator 1, a laser beam control mechanism 8, a position control mechanism 9, a position detecting mechanism 10, and the image discriminating device 13. Deviation of the machining pattern of a conductive thin film relative to an application electrode on a substrate of large area can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for manufacturing a surface conduction electron-emitting device using laser light, and more particularly to an image display device using the same.

[0002]

2. Description of the Related Art FIG. 15 is a schematic diagram of an embodiment of a conventional surface conduction electron-emitting device.

Conventionally, two types of electron emitters, a thermoelectron source and a cold cathode electron source, are known. Cold cathode electron sources include field emission type (hereinafter abbreviated as FE type), metal / insulating layer / metal type (hereinafter abbreviated as MIM type), and surface conduction type electron emitting devices.

As an example of the FE type, W. P. Dyke &
W. W. Dolan, "Fielddemissio
n ", Advance in Electron Ph
ysics, 889 (1956) or C.I. A. S
pindt, "Physical Properties"
of thin-film field emiss
ion cathodes with mollybde
num "J. Appl. Phys., 475248.
(1976) and the like are known.

As an example of the MIM type, C.I. A. Mea
d, "The tunnel-emission am
plier, J. et al. Appl. Phys. , 32 6
46 (1961) and the like are known.

Examples of the surface conduction electron-emitting device include:
M. I. Elinson, Radio Eng. Ele
ctron Phys. 10 (1965) and so on. The surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current is applied to a thin film having a small area formed on a substrate in parallel with the film surface. As the surface conduction electron-emitting device, the S by Erinson et al.
One using an nO ₂ thin film, one using an Au thin film [G. D
ittmer: "Thin Solid Film
s ", 9,317 (1972)] , In 2 0 3 / SnO
₂ Thin film [M. Hartwell and
C. G. FIG. Fonstad: "IEEE Trans.E
D Conf. , 519 (1975)], using a carbon thin film [Hisashi Araki et al .: Vacuum, Vol. 26, No. 1,
22 (1983)].

FIG. 15 shows a typical element structure of these surface conduction electron-emitting devices as described above in M. This is a Hartwell device configuration. In the figure, reference numeral 41 is a substrate. Reference numeral 44 denotes a conductive thin film, which is composed of a metal oxide thin film or the like formed by sputtering on an H-shaped pattern, and an electron emitting portion emitting portion 45 is formed by an energization process called energization forming described later. The element electrode spacing L in the figure
Is set to 0.5 mm to 1 mm, and W 'is set to 0.1 mm. Since the position and shape of the electron emitting portion 45 are unknown, they are shown as a schematic diagram.

Conventionally, in these surface conduction electron-emitting devices, it has been general that the electron-emitting portion 45 is formed in advance by conducting an energization process called energization forming on the conductive thin film 44 before emitting electrons. That is, the energization forming is performed by applying a direct current voltage or a very slow rising voltage, for example, about 1 V / min to both ends of the conductive thin film 44 to locally break, deform or deteriorate the conductive thin film to electrically. This is to form the electron emitting portion 45 in a high resistance state. The electron emitting portion 45 is formed of the conductive thin film 44.
A crack is generated in a part of the area and electrons are emitted from the vicinity of the crack. The surface conduction electron-emitting device that has been subjected to the energization forming process is one in which a voltage is applied to the conductive thin film 44 and a current is passed through the device so that electrons are emitted from the electron-emitting portion 45.

Since the surface conduction electron-emitting device described above has a simple structure and is easy to manufacture, it has an advantage that a large number of devices can be arrayed over a large area. Therefore, various applications that can make full use of this feature are being studied. For example, a charged beam source, a display device such as an image display device may be used.

In order to form the device electrodes and conductive thin films of such surface conduction electron-emitting devices, general semiconductor manufacturing techniques such as vacuum film forming technique, photolithography technique and etching technique have been used. In application to image display devices and the like, laser processing is used for patterning element electrodes and trimming conductive thin films.

[0011]

When laser processing is used for trimming a conductive thin film so as to cope with large area processing, it is necessary to process the element electrode portion accurately and at high speed.

Element electrodes corresponding to such a large area are often formed by a printing technique such as screen printing or offset printing, and the element electrode positions are irregularly displaced on the entire surface of the substrate, or the displacement is varied depending on the substrate. I will end up.

The conventional laser processing apparatus has only a function of processing a preset trimming pattern on the basis of the accuracy of the processing machine, which is almost as designed, and corrects the position according to the deviation of each element position. It was difficult to process.

Therefore, an object of the present invention is to provide a manufacturing apparatus and a manufacturing method of a surface conduction electron-emitting device capable of easily and stably correcting the position of laser processing.

[0015]

A surface conduction electron-emitting device manufacturing apparatus according to a first aspect of the present invention is a laser processing apparatus for moving a workpiece and a laser beam relative to each other, and image information on the surface of the workpiece. It is characterized in that it is provided with a means for taking in and identifying, and a means for detecting the position of the workpiece.

In the second method for manufacturing a surface conduction electron-emitting device, the manufacturing apparatus of the first invention is used, and a step of measuring image information and position information on the surface of the workpiece is provided in advance, and then the laser is used. It is characterized by processing.

[0017]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 5A is a schematic plan view of the structure of a basic surface conduction electron-emitting device of the present invention, and FIG.
6A is a sectional view, FIG. 6A, FIG. 6B, and FIG. 6C are sectional views showing an example of a method of manufacturing the surface conduction electron-emitting device of the present invention in the order of steps, and FIG. FIG. 8 is an example of the voltage waveform of the energization forming, in which (a) is a case where the applied crest value is constant, (b) is an increase, and FIG. 8 is a measurement evaluation for measuring electron emission characteristics. 9 is a schematic configuration diagram of an apparatus, FIG. 9 is a schematic configuration diagram of an electron source having a simple matrix arrangement, FIG. 10 is a perspective view showing a schematic configuration of an image forming apparatus,
11A is a fluorescent film showing a stripe-shaped black conductive material and a phosphor, FIG. 11B is a fluorescent film showing a matrix-shaped black conductive material and a fluorescent material, and FIG. 12 is an NTSC TV signal. FIG. 13 is a block diagram of a drive circuit for performing display according to the above, and an image forming apparatus having the drive circuit. FIG. 13 is a ladder-type arrangement electron source substrate. FIG. 14 is an image forming apparatus including the electron source substrate of FIG. It is a perspective view showing a schematic structure of a device.

The surface conduction electron-emitting device that can be used in the present invention is basically a planar surface conduction electron-emitting device.

In FIG. 5, the substrate 41, the device electrodes 42, 4
3, the conductive thin film 44, and the electron emitting portion 45 are shown.

As the substrate 41, quartz glass, glass containing a small amount of impurities such as Na, soda lime glass, a glass substrate having SiO ₂ formed on its surface, and a ceramic substrate such as alumina are used.

As the material of the device electrodes 42 and 43, general conductors are used, and for example, Ni, Cr, Au, Mo,
A printed conductor composed of a metal or alloy such as W, Pt, Ti, Al, Cu and Pd and a metal or metal oxide such as Pd, Ag, Au, RuO ₂ , Pd-Ag and glass, and
n ₂ 0 ₃ -SnO ₂ or the like transparent conductor and is appropriately selected from semiconductor materials such as polysilicon.

The device electrode spacing L is preferably several hundred angstroms to several hundreds of micrometers. In addition, it is desirable that the voltage applied between the device electrodes is low, and it is required to form the device with good reproducibility. Therefore, the preferred device electrode interval is several micrometers to several tens of micrometers.

The device electrode length W is preferably several micrometers to several hundreds of micrometers in view of the resistance value of the electrodes and electron emission characteristics, and the film thickness of the device electrodes 42 and 43 is preferably several hundreds of angstroms to several micrometers. .

In addition to the structure shown in FIG. 5, the conductive thin film 44 and the electrodes of the device electrodes 42 and 43 may be formed in this order on the substrate 41.

The conductive thin film 44 is particularly preferably a fine particle film composed of fine particles in order to obtain good electron emission characteristics.
The film thickness is appropriately set according to the step coverage to the device electrodes 42 and 43, the resistance value between the device electrodes 42 and 43, and the energization forming condition described later, etc., but is preferably from several angstroms to several thousand angstroms, and particularly preferably. Is 10 angstroms to 500 angstroms. Its sheet resistance value is 10 3 to 10 7 ohm / □.

The material forming the conductive thin film 44 is P
d, Pt, Ru, Ag, Au, Ti, In, Cu, C
metals such as r, Fe, Zn, Sn, Ta, W, Pb, Pd
_{O, SnO 2, In 2 0} 3, PbO, oxides such as _{Sb 2 0 3, HfB 2,} ZrB 2, LaB 6, CeB 6, YB
₄ , boride such as GdB ₄ , TiC, ZrC, HfC, T
carbides such as aC, SiC, WC, TiN, ZrN, Hf
Examples include nitrides such as N, Si, semiconductors such as Ge, carbon, and the like.

The fine particle film described here is a film in which a plurality of fine particles are aggregated, and its fine structure is not only in a state in which fine particles are individually dispersed and arranged but also in a state in which fine particles are adjacent to each other or overlap each other (island). The particle size of the fine particles is from several angstroms to several thousand angstroms, preferably from 10 angstroms to 200 angstroms.

The electron emitting portion 45 is a high resistance crack formed in a part of the conductive thin film 44, and is formed by energization forming or the like. Further, the cracks may have conductive fine particles having a particle diameter of several angstroms to several hundred angstroms. The conductive fine particles contain at least a part of the elements forming the conductive thin film 44. Further, the electron emitting portion 45 and the conductive thin film 44 in the vicinity thereof may contain carbon and a carbon compound.

In the energization forming, electricity is applied between the device electrodes 42 and 43 from a power source (not shown) to locally break, deform or alter the conductive thin film 44 to form a portion having a changed structure. The part where the structure is locally changed is referred to as an electron emission part 45 (FIG. 6C).

The voltage waveform of the energization forming is particularly preferably a pulse waveform, and the voltage waveform shown in FIG. 7 (a) is continuously applied, and the voltage waveform shown in FIG. 7 (b) is continuously applied. In some cases, the voltage pulse is applied while increasing. First, the case where the pulse crest value in FIG. 7A is a constant voltage will be described.

In FIG. 7A, T1 and T2 are the pulse width and pulse interval of the voltage waveform. T1 is 1 microsecond to 10 milliseconds, T2 is 10 microseconds to 100 milliseconds, and the peak value of the triangular wave ( The peak voltage during energization forming) is appropriately selected according to the form of the surface conduction electron-emitting device, and is applied for several seconds to several tens of minutes in a vacuum atmosphere with an appropriate degree of vacuum, for example, about 10 −5 torr. . The waveform applied between the electrodes of the element is not limited to a triangular wave, and a desired waveform such as a rectangular wave may be used.

T1 and T2 in FIG. 7 (b) are the same as those in FIG. 7 (a), and the peak value of the triangular wave (peak voltage during energization forming) is increased by, for example, about 0.1 V step to obtain an appropriate vacuum. Apply in an atmosphere.

In the energization forming process in this case, the element current is measured at a voltage that does not locally break or deform the conductive thin film 4 during the pulse interval T2, for example, a voltage of about 0.1 V, and the resistance is measured. The value is obtained, and when the resistance is 1 M ohm or more, the energization forming is completed.

Next, it is desirable to perform a process called an activation process on the element for which the energization forming has been completed. The activation process is, for example, 10 −4 to 10 −5 tor torr.
Similar to energization forming, it is a process of repeatedly applying a voltage pulse with a constant pulse peak value at a degree of vacuum. Carbon and carbon compounds derived from organic substances existing in a vacuum are deposited on a conductive thin film to form an element. This is a process of significantly changing the current If and the emission current Ie. In the activation process, while measuring the device current If and the emission current Ie, for example,
The process ends when the emission current Ie is saturated. Further, it is preferable that the applied voltage pulse is an operation drive voltage.

The carbon and the carbon compound are graphite (indicating both single and polycrystalline) amorphous carbon (indicating a mixture of amorphous carbon and polycrystalline graphite), and the film thickness thereof is It is preferably 500 angstroms or less, more preferably 300 angstroms or less.

It is preferable that the electron-emitting device thus produced is placed in an atmosphere having a higher vacuum degree than the vacuum degree in the energization forming step and the activation step and is driven. Further, it is desirable to drive the device after heating at 80 ° C. to 150 ° C. in an atmosphere having a higher degree of vacuum.

The degree of vacuum higher than the degree of vacuum obtained by the energization forming step or activation treatment is, for example, a degree of vacuum of about −10 −6 or higher, more preferably an ultrahigh vacuum system, and newly added carbon. And a degree of vacuum in which a carbon compound is hardly deposited on the conductive thin film. By doing so, the device current If and the emission current Ie can be stabilized.

FIG. 8 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring the electron emission characteristics of the device having the configuration of FIG. 5, and the same reference numerals as those in FIG. 5 denote the same elements. And
Power supply 8 for applying a device voltage Vf to the electron-emitting device
1, an ammeter 80 for measuring a device current If flowing through the conductive thin film 44 between the device electrodes 42 and 43, an anode electrode 84 for capturing an emission current Ie emitted from an electron emission portion of the device, an anode electrode High voltage power supply 83 for applying voltage to 84, ammeter 82 for measuring emission current Ie emitted from electron emission portion 45 of the device, vacuum device 8
5, the exhaust pump 86 is shown.

Next, the image forming apparatus of the present invention will be described. The electron source substrate used in the image forming apparatus is formed by arranging a plurality of surface conduction electron-emitting devices on the substrate.

As a method of arranging the surface conduction electron-emitting devices, the surface conduction electron-emitting devices are arranged in parallel, and both ends of the individual devices are connected by a ladder arrangement (hereinafter referred to as a ladder-type arrangement electron source substrate and And a simple matrix arrangement (hereinafter referred to as a matrix-type arrangement electron source substrate) in which an X-direction wiring and a Y-direction wiring are connected to a pair of device electrodes of a surface conduction electron-emitting device, respectively. An image forming apparatus having a ladder-type electron source substrate requires a control electrode (grid electrode) which is an electrode for controlling the flight of electrons from the electron-emitting device.

The configuration of the electron source constructed based on this principle will be described below with reference to FIG. Electron source substrate 91,
The X-direction wiring 92, the Y-direction wiring 93, the surface conduction electron-emitting device 94, and the connection 95 are shown. The surface conduction electron-emitting device 94 may be either the flat type or the vertical type described above. In FIG. 9, the substrate used as the electron source substrate 91 is the above-mentioned glass substrate or the like, and the shape is appropriately set according to the application. The X-direction wiring 92 is Dx1,
The wirings in the Y direction 93 are composed of m wirings DX2, ..., Dxm, and the n wirings in Dy1, Dy2 ... Dyn. Further, the material, the film thickness, and the wiring width are appropriately set so that a substantially uniform voltage is supplied to many surface conduction electron-emitting devices. The m X-direction wirings 92 and the n Y-direction wirings 93 are electrically separated by an interlayer insulating layer (not shown) to form a matrix wiring (m and n are both positive integers).

An interlayer insulating layer (not shown) is formed in a desired region on the entire surface or a part of the substrate 91 on which the X-direction wiring 92 is formed. The X-direction wiring 92 and the Y-direction wiring 93 are drawn out as external terminals. Further, the surface conduction electron-emitting device 9
The four element electrodes (not shown) are electrically connected to the m X-direction wirings 92 and the n Y-direction wirings 93 by connection lines 95. The surface conduction electron-emitting device may be formed either on the substrate or on an interlayer insulating layer (not shown).

The X-direction wiring 9 will be described in detail later.
2 is electrically connected to a scanning signal generating means (not shown) for applying an operation signal for scanning a row of surface conduction electron-emitting devices 94 arranged in the X direction according to an input signal. On the other hand, a modulation signal generating means (not shown) for applying a modulation signal for modulating each row of the surface conduction electron-emitting devices 94 arranged in the Y direction to the Y-direction wiring 93 according to an input signal. Is electrically connected to. Further, the drive voltage applied to each element of the surface conduction electron-emitting device is supplied as a difference voltage between the scanning signal and the modulation signal applied to the element.

In the above structure, individual elements can be selected and driven independently by using only simple matrix wiring.

Next, an image forming apparatus using the matrix type arrangement electron source substrate produced as described above will be described with reference to FIGS. 10, 11 and 12. FIG.
In, an electron source substrate 91 having an electron-emitting device formed on the substrate, a rear plate 101 having the electron source substrate 91 fixed thereto,
A face plate 106 having a fluorescent film 104, a metal back 105 and the like formed on the inner surface of a glass substrate 103, and a support frame 102 are shown, and the envelope 10 is formed by these members.
8 are configured.

In FIG. 10, the electron-emitting device 94 is shown in FIG.
Corresponds to the electron emitting portion 45 in. The X-direction wiring 92 and the Y-direction wiring 93 connected to the pair of device electrodes of the surface conduction electron-emitting device correspond to those described with reference to FIG.

The envelope 108 is composed of the face plate 106, the support frame 102, and the rear plate 101 as described above, but the rear plate 101 is provided mainly for the purpose of reinforcing the strength of the electron source substrate 91. Electron source substrate 91
Separate rear plate 10 if it has sufficient strength
1 is unnecessary, and the support frame 102 is directly attached to the electron source substrate 91.
Alternatively, the face plate 106, the support frame 102, and the electron source substrate 91 may constitute the envelope 108. Furthermore, by providing an atmospheric pressure resistant support member called a spacer between the face plate 106 and the rear plate 101, the envelope 108 having sufficient strength against atmospheric pressure can be obtained.

In FIG. 11, the phosphor 112 is made of only the phosphor in the case of a monochrome phosphor film, but in the case of a color phosphor film, a black conductive material called a black stripe or a black matrix depending on the arrangement of the phosphors. 111 and a phosphor 112. In the case of color display, the purpose of providing the black stripes and the black matrix is each phosphor 112 of the three primary color phosphors required.
This is to make the color mixture portions inconspicuous by blackening the colored portions between them and to suppress the deterioration of the contrast due to the reflection of external light on the fluorescent film 104. The material of the black stripe is not limited to the commonly used material containing graphite as a main component, but is not limited to this as long as it is a material that is electrically conductive and has little light transmission and reflection.

As a method of applying the phosphor to the glass substrate 103, a precipitation method or a printing method is used regardless of monochrome or color. Further, a metal back 105 (FIG. 10) is usually provided on the inner surface side of the fluorescent film 104 (FIG. 10). The purpose of the metal back is to improve the brightness by specularly reflecting the light to the inner surface side of the phosphor emission toward the face plate 106 side, to act as an electrode for applying an electron beam accelerating voltage, This is to protect the phosphor from the damage caused by the collision of negative ions generated inside the container. The metal back can be formed by performing a smoothing treatment (usually called filming) on the inner surface of the fluorescent film after forming the fluorescent film, and then depositing Al by vacuum evaporation or the like.

The face plate 106 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 104 in order to further enhance the conductivity of the fluorescent film 104.

The envelope 108 is provided with an exhaust pipe (not shown)
0^{ー 7}The degree of vacuum is set to about torr and sealing is performed. Ma
In order to maintain the vacuum degree after the sealed envelope 108 is sealed,
In some cases, processing is performed. This is the envelope 108
Resistance heating or high frequency just before stopping or after sealing
A predetermined position in the envelope 108 by a heating method such as heating.
Heat the getter (not shown) and shape the deposited film.
It is a process to be performed. The getter usually has Ba as a main component.
By the adsorption action of the deposited film, for example, 1 × 10 ^-5to
rr or 1 × 10^{ー 7}Maintaining a vacuum of torr
It is. Forming of the surface conduction electron-emitting device
The subsequent steps are set as appropriate.

Next, referring to the block diagram of FIG. 12, a schematic structure of a drive circuit for performing a television display based on an NTSC system television signal in an image forming apparatus constructed by using a matrix type electron source substrate will be described. explain. Display panel 121, scanning circuit 122, control circuit 123, shift register 124, line memory 125, sync signal separation circuit 1
26, modulation signal generator 127, DC voltage sources Vx and V
a is shown.

The functions of the respective parts will be described below. First, the display panel 121 includes terminals Doxl to Doxm and a terminal D.
It is connected to an external electric circuit via oyl or Doyn and the high voltage terminal Hv. Among them, the terminals Doxl to Doxm sequentially drive the electron sources provided in the image forming apparatus, that is, the surface conduction electron-emitting devices which are arranged in a matrix of m rows and n columns matrix by row (n elements). A scanning signal for application is applied.

On the other hand, a modulation signal for controlling the output electron beam of each element of the surface conduction electron-emitting devices of one row selected by the above-mentioned scanning signal is applied to the terminals Dyl to Dyn. The high voltage terminal Hv is supplied with a DC voltage of, for example, 10 [kV] from the DC voltage source Va, which is sufficient to excite the phosphor into the electron beam output from the surface conduction electron-emitting device. It is an accelerating voltage for applying energy.

Next, the scanning circuit 122 will be described. The circuit includes m switching elements inside (indicated by S1 to Sm in the figure), and each switching element is an output voltage of the DC voltage source Vx or 0.
One of [V] (ground level) is selected and electrically connected to the terminals Dxl to Dxm of the display panel 121. Each of the switching elements Sl to Sm operates based on the control signal Tscan output by the control circuit 123, but can be actually configured by combining switching elements such as FETs.

The DC voltage source Vx is a driving voltage applied to an unscanned device based on the characteristics (electron emission threshold voltage) of the surface conduction electron-emitting device. It is set to output a constant voltage that is less than or equal to the voltage.

Further, the control circuit 123 has a function of matching the operation of each part so that an appropriate display is performed based on an image signal input from the outside. The synchronization signal Ts sent from the synchronization signal separation circuit 126 described next
The control signals of Tscan, Tsft, and Tmry are generated for each unit based on the sync.

The sync signal separation circuit 126 is a circuit for separating a sync signal component and a luminance signal component from an externally input NTSC television signal and can be constructed by using a frequency separation (filter) circuit. . As is well known, the sync signal separated by the sync signal separation circuit 126 includes a vertical sync signal and a horizontal sync signal.
Here, it is illustrated as a Tsync signal for convenience of explanation.
On the other hand, the luminance signal component of the image separated from the above-mentioned television signal is referred to as a DATA signal for convenience, but this signal is input to the shift register 124.

The shift register 124 is for serial / parallel conversion of the DATA signal serially input in time series for each line of the image, and operates based on the control signal Tsft sent from the control circuit 123. To do. (That is, the control signal Tsft may be rephrased as a shift lock of the shift register 124.) The data of one line of the serial / parallel-converted image (corresponding to drive data for n electron-emitting devices) is Id.
It is output from the shift register 124 as n parallel signals of 1 to Idn.

The line memory 125 is a storage device for storing data for one line of the image for a required time, and stores the contents of Idl to Idn as appropriate in accordance with the control signal Tmry sent from the control circuit 123. The stored contents are output as Idl to Idn and input to the modulation signal generator 127.

The modulation signal generator 127 is a signal source for appropriately driving and modulating each of the surface conduction electron-emitting devices according to each of the image data Idl to Idn, the output signal of which is output through the terminals Doyl to Doyn. The voltage is applied to the surface conduction electron-emitting device in the display panel 121.

The electron-emitting device according to the present invention has an emission current I.
It has the following basic characteristics for e. That is, the electron emission has a clear threshold voltage Vth, and the electron emission occurs only when a voltage equal to or higher than Vth is applied. Further, for a voltage equal to or higher than the electron emission threshold value, the emission current also changes according to the change in the voltage applied to the element. The value of the electron emission threshold voltage Vth and the degree of change of the emission current with respect to the applied voltage may be changed by changing the material, configuration, and manufacturing method of the electron emitting device. I can say.

That is, when a pulsed voltage is applied to this element, for example, electron emission does not occur even if a voltage below the electron emission threshold is applied, but when a voltage above the electron emission threshold is applied, the electron beam is emitted. Is output. At that time, first, it is possible to control the intensity of the output electron beam by changing the peak value Vm of the pulse. Second,
By changing the pulse width Pw, it is possible to control the total amount of charges of the output electron beam. Therefore, as a method of modulating the electron-emitting device according to the input signal, there are a voltage modulation method, a pulse width modulation method, and the like. To implement the voltage modulation method, the modulation signal generator 1 is used.
As the circuit 27, a circuit of a voltage modulation system is used which generates a voltage pulse of a fixed length but appropriately modulates the peak value of the pulse according to the input data.

Further, in order to implement the pulse width modulation method, the modulation signal generator 127 generates a voltage pulse having a constant peak value, but a pulse which appropriately modulates the width of the voltage pulse according to the input data. A width modulation type circuit is used.

Through the series of operations described above, the image forming apparatus of the present invention can display television using the display panel 121. Although not particularly described in the above description, the shift register 124 and the line memory 125 may be of a digital signal type or an analog signal type, and the point is that serial / parallel conversion and storage of image signals are predetermined. It should be done at speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the sync signal separation circuit 126 into a digital signal, which can be achieved by providing an A / D converter at the output section of 126. Further, in connection with this, the circuit used for the modulation signal generator 127 is slightly different depending on whether the output signal of the line memory 125 is a digital signal or an analog signal.

First, the case of digital signals will be described.
In the voltage modulation method, for example, a well-known D / A conversion circuit may be used as the modulation signal generator 127, and an amplification circuit or the like may be added if necessary. In the case of the pulse width modulation method, the modulation signal generator 127 is, for example, a high-speed oscillator and a counter that counts the number of waves output by the oscillator and a comparator that compares the output value of the counter with the output value of the memory. It can be configured by using a circuit in which (comparators) are combined. If necessary, an amplifier for voltage-amplifying the pulse-width-modulated modulation signal output from the comparator up to the drive voltage of the surface conduction electron-emitting device may be added.

Next, the case of an analog signal will be described.
In the voltage modulation method, for the modulation signal generator 127, for example, an amplifier circuit using a well-known operational amplifier may be used, and a level shift circuit or the like may be added if necessary. In the case of the pulse width modulation method, for example, a well-known voltage controlled oscillation circuit (VCO) may be used, and an amplifier for amplifying the voltage to the drive voltage of the surface conduction electron-emitting device may be used if necessary. May be added.

In the image forming apparatus completed as described above, each of the electron-emitting devices has terminals outside the container Doxl to Dx.
Electrons are emitted by applying a voltage through oym or Doyn, and a high voltage is applied to the metal back 105 or the transparent electrode (not shown) through the high voltage terminal Hv.
The electron beam is accelerated to collide with the fluorescent film 104 to excite
An image can be displayed by emitting light.

The above-described structure is a schematic structure necessary for producing a suitable image forming apparatus used for display or the like, and the detailed parts such as the material of each member are not limited to the above contents. , Is appropriately selected to suit the application of the image forming apparatus. Further, although the NTSC system is given as an example of the input signal, the input signal is not limited to this, and PAL, SECA
Various methods such as the M method may be used, or a TV signal (for example, a high-definition TV such as the MUSE method) including a number of scanning lines may be used.

Next, the ladder-type arrangement electron source substrate and the image forming apparatus using the same will be described with reference to FIGS. 13 and 14.

FIG. 13 shows an electron source substrate 130, an electron emitting element 131, and a common wiring 132 (Dx1 to Dx10) connected to this electron emitting element. A plurality of electron-emitting devices 131 are arranged on the substrate 130 in parallel in the X direction. (This is called the element row). A plurality of the element rows are arranged on the substrate to form a ladder type electron source substrate. By appropriately applying a drive voltage between the common wirings of each element row, each element row can be independently driven. That is,
A voltage equal to or higher than the electron emission threshold may be applied to an element row that emits an electron beam, and a voltage equal to or lower than the electron emission threshold may be applied to an element row that does not emit an electron beam. Further, the common wirings Dx2 to Dx9 between the element rows, for example, Dx2 and Dx3 may be the same wiring.

FIG. 14 is a view showing the structure of an image forming apparatus having a ladder-type electron source. Grid electrode 1
40, holes 141, Dox1, Do because electrons pass through
x2. . . Doxm outer terminal 142, G1, G2 ,. . . The external terminal 143 made of Gn and the electron source substrate 130 in which the common wiring between the respective element rows is the same wiring as described above are shown. The same reference numerals as those in FIGS. 10 and 13 denote the same members. The image forming apparatus having the above-mentioned simple matrix arrangement (see FIG.
The difference from 0) is that the grid electrode 140 is provided between the electron source substrate 130 and the face plate 106.

A grid electrode 140 is provided between the substrate 130 and the face plate 106. The grid electrode 140 is capable of modulating the electron beam emitted from the surface conduction electron-emitting device, and is for passing the electron beam through the stripe-shaped electrodes provided orthogonal to the ladder-shaped arrangement of the element rows. A circular hole 141 corresponding to each element is provided. The shape and installation position of the grid are not necessarily as shown in FIG. 14, and a large number of passage openings may be provided in the form of a mesh as openings. For example, they may be provided around or near the surface conduction electron-emitting device. Good.

The external terminal 142 and the grid external terminal 143 are electrically connected to a control circuit (not shown).

In this image forming apparatus, the modulation signals for one line of the image are simultaneously applied to the grid electrode columns in synchronization with the sequential driving (scanning) of the element rows one column at a time.
The irradiation of each electron beam to the phosphor can be controlled to display an image line by line.

Further, according to the present invention, it is possible to provide an image forming apparatus suitable for not only a display device for television broadcasting but also a display device such as a video conference system and a computer. Further, it can be used as an image forming apparatus as an optical printer including a photosensitive drum or the like. Further, not only surface conduction electron-emitting devices but also cold cathode electron sources such as MIM electron-emitting devices and field emission electron-emitting devices can be applied as electron-emitting devices, and further to an image forming apparatus using a thermoelectron source. Can also be applied.

[0079]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a surface conduction electron-emitting device using a laser beam according to the present invention, FIGS.
FIG. 3D is a schematic view showing a situation during laser processing in the case where there is a deviation in the element electrode group and in the case where there is no deviation, and FIGS.
(D) is a schematic diagram according to FIG. 2 showing a situation during laser processing in the case where the element electrode group is displaced.

FIG. 1 is a view best showing the features of the present invention, and shows the structure of a laser processing apparatus used for forming a conductive thin film of a surface conduction electron-emitting device. The configuration will be described below.

In FIG. 1, a laser oscillator 1 as a laser light source and a high-speed shutter 2 for turning on / off a laser beam irradiates the laser beam toward a workpiece 7 by a half mirror 3, and at the same time, the workpiece is processed. The surface of 7 is observed through this half mirror 3.

The slit 4 shapes the shape of the light flux of the laser light, and the objective lens 5 focuses the laser light on the surface of the workpiece 7 and enlarges the surface of the workpiece 7. The XY direction scanning mechanism 6 moves the workpiece 7 in the XY directions relative to the laser light. The laser light control mechanism 8 uses the high-speed shutter 2
The position control mechanism 9 and the position detection mechanism 10 position-correct the movement of the XY direction scanning mechanism.

The image capturing device 12 captures the image of the surface of the workpiece 7 which is enlarged by the objective lens 5 and transmitted by the half mirror 3. The image identification device 13 includes an image capturing device 12
Identify the images captured in. Image display monitor 14
Displays the image captured by the image capturing device 12. The control computer 11 centrally controls the laser oscillator 1, the laser light control mechanism 8, the position control mechanism 9, the position detection mechanism 10, and the image identification device 13.

In the schematic diagrams showing the processing of the conductive thin film of the surface conduction electron-emitting device by the laser processing of FIGS. 2 and 3, the device electrodes 42 and 43, the processing pattern 20, and the corrected processing pattern 21 and the pattern. The misaligned portion 22 is shown. 2 and 3, the conductive thin film 44 is shown in a transparent state, not shown, in order to facilitate understanding of the positional relationship between the device electrode and the processing pattern.

The manufacturing apparatus and manufacturing method of the surface conduction electron-emitting device of the present invention will be sequentially described with reference to FIGS.

First, in FIG. 2A, Pt is formed on the glass substrate.
The device electrodes are formed in a matrix by the sputtering method and the photolithography / etching process. These element electrode groups are created with a positional accuracy of several μm, almost as designed. Organic palladium is applied on the entire surface and baked at 300 ° C. for 20 minutes to form a conductive thin film made of a fine particle film containing Pd as a main component. In addition,
As described above, the conductive thin film is shown in FIG. The processed pattern 20 of (b) is formed so that the conductive thin film is insulated for each device electrode.
However, in the case of (b), the processing pattern according to the design value can be used for insulation without any problem. However, when the Pt element electrode is formed by the printing method as shown in (c), the position of the element electrode group is likely to deviate from the design value, and an error of about 30 μm may occur at 300 mm. It is often different for each lot. (C) schematically shows the deviation, which is the processing pattern 20 having the same design value as (b).
Even if the laser processing is performed in step (d), pattern deviation 22 occurs as shown in FIG. Therefore, in such a case, the laser processing apparatus of the present invention is used, which will be described with reference to the apparatus diagram of FIG. 1 and the processing schematic diagram of FIG.

As shown in FIG. 3A, when the element electrode (Pt) deviated from the design value is formed on the glass by the printing method, the image capturing device (in this example, the CCD (Used) 12 is enlarged by the objective lens 5, and the half mirror 3 is used.
The image information that has passed through is captured, and the center of gravity position can be identified by the image identification device 13 from the contrast of the element electrode.
Therefore, while the XY-direction scanning mechanism 6, the position control mechanism 9, and the position detection mechanism 10 relatively move the entire surface of the workpiece with the image capturing device 12, the image identifying device 13 identifies the element electrode, and thus the image capturing device 12 in FIG. Accurate position information of the element electrode group in (a) is collected, and the processing pattern data 21 in which the deviation amount is corrected in FIG. 3 (b) is immediately generated by the control computer in FIGS. A laser beam generated from the laser oscillator 1 of FIG. 1 is bent at a right angle by a half mirror 3 through a high-speed shutter 2, the shape of the laser beam is adjusted by a slit 4, and the laser beam is condensed by an objective lens 5 to be processed. 7
The surface is irradiated. At this time, the XY-direction scanning mechanism and the high-speed shutter 2 are arranged according to the corrected processing pattern 21.
The workpiece is processed as shown in FIG. As described above, as shown in the enlarged view (d) of the element electrode, the conductive thin film (not shown) corrected for the displacement is processed.

In this embodiment, YA with a Q switch is used.
G 2nd high frequency laser (wavelength 532 nm) is used, Q switch frequency 1 KHz, average output 5 W laser beam diameter 10
μm, and the feed rate of the workpiece was 10 mm / sec.

Subsequently, energization forming was performed by applying a voltage as shown in FIG. At this time, the forming voltage waveform has a pulse width T1 of 1 mse.
c, the pulse interval T2 is a rectangular wave of 10 msec, and the peak value is 1
It was set to 5 V and performed in a vacuum atmosphere. By this energization treatment, the conductive thin film 23 was locally destroyed, deformed or denatured, and the electron emitting portion 45 having a changed structure was obtained.

A matrix type arrangement electron source substrate having surface conduction electron-emitting devices is prepared in this manner, and is sealed to the face plate 106, the support frame 102, the rear plate 101, etc., as shown in FIG. An image forming apparatus was created.

As a result of processing the conductive thin film using the laser processing apparatus of the present invention, it was possible to carry out the processing such that pattern deviation did not occur and each element was reliably insulated.

Next, a second embodiment of the present invention will be described.

FIG. 4 is a block diagram of the second embodiment of the present invention.

In Example 1, the correction of the processing pattern was also performed only by the XY direction scanning mechanism. In the second embodiment, the beam scanner 15 and the beam scan control mechanism 16 are provided to finely adjust the irradiation position of the laser light itself. An acousto-optic device was used as the beam scanner.

[0096]

As described above, the present invention comprises means for capturing and identifying the surface image of the workpiece and means for detecting the position of the workpiece by moving the workpiece and the laser beam relative to each other. In addition, or by providing a process to measure the image position information of the workpiece in advance, the conductive thin film processing pattern does not deviate even on the applied electrode on a large area substrate, and stable processing is always performed. Therefore, it is possible to provide the manufacturing apparatus and the manufacturing method of the surface conduction electron-emitting device which can achieve high yield.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a surface conduction electron-emitting device using laser light of the present invention.

FIG. 2A to FIG. 2D are schematic diagrams showing a situation during laser processing in the case where the element electrode group is displaced and the case where it is not displaced.

3 (a) to 3 (d) are schematic views according to FIG. 2 showing a situation during laser processing in the case where there is a deviation in a device electrode group.

FIG. 4 is a configuration diagram of a second embodiment of the present invention.

5A is a schematic plan view of the structure of a basic surface conduction electron-emitting device of the present invention, and FIG. 5B is a sectional view of FIG.

6 (a), (b), and (c) are cross-sectional views showing an example of a method of manufacturing a surface conduction electron-emitting device of the present invention in the order of steps.

FIG. 7 is an example of a voltage waveform of energization forming according to the present invention, in which (a) shows a case where the applied crest value is constant.
(B) is a case of increasing.

FIG. 8 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring electron emission characteristics.

FIG. 9 is a schematic configuration diagram of an electron source having a simple matrix arrangement.

FIG. 10 is a perspective view showing a schematic configuration of an image forming apparatus.

FIG. 11A is a fluorescent film showing a stripe-shaped black conductive material and a phosphor, and FIG. 11B is a fluorescent film showing a matrix-shaped black conductive material and a fluorescent material.

12A and 12B are a block diagram of a driver circuit for performing display in accordance with an NTSC television signal and an image forming apparatus including the driver circuit.

FIG. 13 is a ladder type electron source substrate.

14 is a perspective view showing a schematic configuration of an image forming apparatus including the electron source substrate of FIG.

FIG. 15 is a schematic configuration diagram of an example of a conventional surface conduction electron-emitting device.

[Explanation of symbols]

1 Laser Oscillator 2 High Speed Shutter 3 Half Mirror 4 Slit 5 Objective Lens 6 XY Direction Scanning Mechanism 7 Workpiece 8 Laser Light Control Mechanism 9 Position Control Mechanism 10 Position Detection Mechanism 11 Control Computer 12 Image Capture Device 13 Image Identification Device 14 Image Display Monitor 15 Beam scanner 16 Beam scan control mechanism 20 Processing pattern 21 Corrected processing pattern 22 Part where pattern shift occurs 41 Substrate 42, 43 Element electrode 44 Conductive thin film 45 Electron emission section 46 Step forming section 80 Element electrode 42/43 Ammeter for measuring the device current If flowing through the conductive thin film 4 between 81 Power supply for applying the device voltage Vf to the electron-emitting device 82 For measuring the emission current Ie emitted from the electron-emitting portion 45 of the device Ammeter 83 of the anode electrode 84 High-voltage power supply for applying voltage 84 Emission current Ie emitted from electron-emitting portion of device
Anode electrode 85 for capturing the electrons 85 Vacuum device 86 Exhaust pump 91 Electron source substrate 92 X-direction wiring 93 Y-direction wiring 94 Surface conduction electron-emitting device 95 Connection 101 Rear plate 102 Support frame 103 Glass substrate 104 Fluorescent film 105 Metal back 106 Face plate 107 High voltage terminal 108 Envelope 111 Black conductive material 112 Phosphor 121 Display panel 122 Scanning circuit 123 Control circuit 124 Shift register 125 Line memory 126 Synchronous signal separation circuit 127 Modulation signal generator 130 Electron source substrate 131 Electron emitting device 132 (Dx1 to Dx10) Common wiring for wiring the electron-emitting device 131 140 Grid electrode 141 Holes through which electrons pass 142 Dox1, Dox2. . . Outer container terminal 143 made of Doxm G1, G connected to the grid electrode 140
2. . . Outer terminal made of Gn

Claims (2)

[Claims] 1. A laser processing apparatus for relatively moving a workpiece and a laser beam, comprising means for capturing and identifying image information on the surface of the workpiece, and means for detecting the position of the workpiece. An apparatus for manufacturing a surface conduction electron-emitting device using laser light, which is characterized by being provided. 2. A surface using laser light, characterized in that the manufacturing apparatus according to claim 1 is used to previously provide a step of measuring image information and position information of a surface of a workpiece, and thereafter perform laser processing. Manufacturing method of conduction electron-emitting device.