US20070215473A1 - Method for sequentially electrophoresis depositing carbon nanotube of field emission display - Google Patents
Method for sequentially electrophoresis depositing carbon nanotube of field emission display Download PDFInfo
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- US20070215473A1 US20070215473A1 US11/377,419 US37741906A US2007215473A1 US 20070215473 A1 US20070215473 A1 US 20070215473A1 US 37741906 A US37741906 A US 37741906A US 2007215473 A1 US2007215473 A1 US 2007215473A1
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- 238000001962 electrophoresis Methods 0.000 title claims abstract description 63
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 51
- 239000002041 carbon nanotube Substances 0.000 title claims abstract description 51
- 229910021393 carbon nanotube Inorganic materials 0.000 title claims abstract description 51
- 238000000151 deposition Methods 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 33
- 230000008021 deposition Effects 0.000 claims abstract description 23
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- 150000003839 salts Chemical class 0.000 claims description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 4
- 239000000654 additive Substances 0.000 claims description 3
- 230000000996 additive effect Effects 0.000 claims description 3
- 239000011521 glass Substances 0.000 claims description 3
- APHGZSBLRQFRCA-UHFFFAOYSA-M indium(1+);chloride Chemical compound [In]Cl APHGZSBLRQFRCA-UHFFFAOYSA-M 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 238000007650 screen-printing Methods 0.000 claims description 3
- 229910021617 Indium monochloride Inorganic materials 0.000 claims description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 2
- NWAIGJYBQQYSPW-UHFFFAOYSA-N azanylidyneindigane Chemical compound [In]#N NWAIGJYBQQYSPW-UHFFFAOYSA-N 0.000 claims description 2
- 238000010891 electric arc Methods 0.000 claims description 2
- 229910052697 platinum Inorganic materials 0.000 claims description 2
- 238000000926 separation method Methods 0.000 claims description 2
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- 239000010936 titanium Substances 0.000 claims description 2
- 239000011265 semifinished product Substances 0.000 claims 1
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- 238000005137 deposition process Methods 0.000 description 9
- 238000004519 manufacturing process Methods 0.000 description 7
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000009826 distribution Methods 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
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- 239000002245 particle Substances 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B7/00—Electrophoretic production of compounds or non-metals
Definitions
- the present invention relates to a method for electrophoresis depositing carbon nanotube on cathode strip for a field emission display, especially to a method for electrophoresis depositing carbon nanotube with certain powders such as glass powder or conductive powder.
- the field emission display uses cathode electron emitter to generate electron by electrical field.
- the emitted electron excites phosphor on anode plate for illumination.
- the field emission display has compact size and flexible viewable area.
- the field emission display does not have view angle problem encountered in LCD.
- triode field emission display includes an anode structure and a cathode structure. There is a spacer disposed between the anode structure and the cathode structure, thereby providing a space and a support for the vacuum region between the anode structure and the cathode structure.
- the anode structure includes an anode substrate, an anode conducting layer, and a phosphorus layer.
- the cathode structure includes a cathode substrate, a cathode conducting layer, an electron emission layer, a dielectric layer and a gate layer. The gate layer provides a voltage difference to induce the emission of electrons from the electron emission layer.
- the conducting layer of the cathode structure provides a high voltage to accelerate the electron beam, such that the electron beam can have enough kinetic energy to impinge and excite the phosphorous layer on the anode structure, thereby emitting light. Accordingly, in order to maintain the movement of electrons in the field emission display, a vacuum apparatus is required to keep the vacuum degree of the display being below 10 ⁇ 5 torr. Therefore, the electrons can have appropriate mean free paths. Meanwhile, the pollution and toxication of the electron emission source and the phosphorous layer should be prevented from happening. Furthermore, in order for the electrons to accumulate enough energy to impinge the phosphorous powder, a predetermined gap is required between the two substrates. Consequently, the electrons can be accelerated to impinge the phosphorous layer, thereby exciting the phosphorous layer and emitting light therefrom.
- the electron emission layer is composed of carbon nanotubes. Since carbon nanotubes, proposed by Iijima in 1991 (Nature, 354, 56 (1991)), possess very good electronic properties that can be used to build a variety of devices. The carbon nanotubes also has a very large aspect ratio, mostly larger than 500, and a very high rigidity of Young moduli larger than 1000 GPn. In addition, the tips or defects of the carbon nanotubes are of atomic scale. The properties described above are considered an ideal material for building electron field emitter, such as an electron emission source of a cathode structure of a field emission display. Since the carbon nanotubes comprise the physical properties described above, a variety of manufacturing process can be developed, e.g. screen printing, or thin film processing.
- the art of manufacturing the cathode structure employs carbon nanotubes as an electron emission material, which is fabricated on the cathode conducting layer.
- the manufacturing process can employ chemical vapor deposition (CVD) process, or any kind of process that can pattern the photosensitive carbon nanotube solution on any pixel of the cathode conducting layer.
- the cathode structure can also be manufactured by coating the carbon nanotubes solution while incorporating with a mask, or depositing the carbon nanotubes on the cathode conducting layer by an electrophoresis method.
- CVD chemical vapor deposition
- the cathode structure can also be manufactured by coating the carbon nanotubes solution while incorporating with a mask, or depositing the carbon nanotubes on the cathode conducting layer by an electrophoresis method.
- the applicant of the present invention had also proposed a pulse electrophoresis deposition process to enhance uniformity of carbon nanotube.
- the deposition amount in unitary area is enhanced and the process can be used for aqueous solution.
- the current pulse electrophoresis deposition process still have following problems.
- the area electrophoresis is difficult for electrophoresis solution with complicated carbon nanotube suspension. Some particles are added to the electrophoresis solution to enhance the adhesion ability of carbon nanotube and the effect of manufacturing electron emission source.
- the carbon nanotube suspension is sensitive to electrical field distribution, and to concentration and thickness of the display. This problem is more serous for large-size display.
- the pulse electrophoresis deposition process has good effect for aqueous solution.
- the property of solution is critical to some carbon nanotube.
- some non-aqueous solution such as alcohol solution has good property for most carbon nanotube.
- the pulse electrophoresis deposition process uses larger current and has burning risk for alcohol solution.
- the impedance distribution of cathode strip depends on distribution variation of strip length. Therefore, the impedance variation is serious, especially for large-size display.
- the end of the cathode strip close to power source encounters larger current and has greater deposition concentration. The electrophoresis deposition is not uniform.
- the present invention is to provide a method for sequentially electrophoresis depositing carbon nanotube of field emission display.
- the current is large and the deposition is spares. Therefore, the electrophoresis deposition is not uniform for solution with complicated composition.
- the electrophoresis deposition is localized to one single cathode strip at one time. The complicated particles in the solution is deposited on the single cathode strip, and the remaining cathode strips are conducted successively and individually for global electrophoresis deposition.
- the present invention provides a method for sequentially electrophoresis depositing carbon nanotube of field emission display.
- the anode ends of a power source are connected to anode strips of an anode plate.
- the cathode ends of the power source are connected to one input ends of a plurality of controllers.
- the output ends of the controllers are connected to a plurality of cathode strips of a cathode plate.
- a signal generator is connected to another input ends of the controllers.
- An electrophoresis tank is provided with electrophoresis solution therein and the anode plate and the cathode plate are placed parallel in the electrophoresis tank.
- the voltages from anode ends of the power source is output to the anode strips.
- the signal generator sends pulse voltage signal to one of the controllers such that one of the cathode strip is conducted while the remaining cathode strips are not conducted, whereby only one electrical field is present for one pixel at one time and carbon nanotube is formed at that pixel.
- the next cathode strip is conducted successively and the remaining cathode strips are non-conducted to fabricate carbon nanotube electron emission source in sequential manner.
- FIG. 1 shows a schematic diagram of the anode plate and cathode plate according to a preferred embodiment of the present invention.
- FIG. 2 shows the schematic diagram of connection of the anode plate and cathode plate to the electrophoresis deposition equipment.
- FIG. 3 shows the schematic diagram of connection of the anode plate and cathode plate to the electrophoresis deposition equipment during fabrication.
- FIG. 4 shows a simplified schematic diagram of connection of the anode plate and cathode plate to the electrophoresis deposition equipment.
- sequential electrophoresis deposition localizes current to a single pixel to fabricate carbon nanotube electron emission source. Therefore, the peak current can be reduced and the method can be applied to manufacture of large display.
- a cathode plate 1 is prepared with a plurality of cathode strips 11 (such as 32 cathode strips).
- the cathode strips 11 are already formed with gate and semi-finished sacrifice layer.
- the sacrifice layer is used to prevent unwanted deposition (such as gate, dielectric) on the non-electrophoresis deposition area.
- the sacrifice layer is removed after electrophoresis deposition process.
- an anode plate 2 is prepared and the anode plate 2 is formed by platinum, titanium plate or screen-printing plate.
- a power source 3 is connected to the anode plate 2 by anode ends 31 thereof and is connected to input ends of controllers 4 by cathode ends 32 thereof
- the controller 4 is connected to the cathode strips 11 by output ends thereof.
- the controller 4 Another input end of the controller 4 is connected to a signal generator 5 to complete the connection for electrophoresis depositing.
- the signal generator 5 provides sequential signal for the cathode strips 11 .
- the controller 4 controls a conducting and an un-conducting state for the cathode strips 11 and can be realized by signal amplifier or switch.
- the signal amplifier decides to amplify or not to amplify the output signal from the signal generator 5 .
- a potential difference is present between the cathode strip 11 and the anode plate to provide an electrical field. Therefore, carbon nanotube electron emission source can be fabricated on a single cathode strip 11 .
- the above-mentioned switch is a timing switch and conducts a predetermined time period such that the signal generated by the signal generator 5 is applied to one cathode strip 11 .
- a potential difference is present between the cathode strip 11 and the anode plate to provide an electrical field. Therefore, carbon nanotube electron emission source can be fabricated on a single cathode strip 11 .
- the switch is turned off and a next conduction period is provided for a next single cathode strip 11 for fabricating carbon nanotube electron emission source successively.
- an electrophoresis solution is prepared for the electrophoresis tank 6 .
- Alcohol is used for solution and carbon nanotube is used for electron emission source and manufactured by arc discharge.
- the carbon nanotube has average length below 5 ⁇ m and average diameter below 100 nm.
- the carbon nanotube has multiple wall, the carbon nanotube has an additive concentration of 0.1%-0.005% (preferably 0.02%).
- the charger uses metal salt is conductive after electrophoresis, for example, the metal salt is one of InCl and indium nitride or other salt with tin.
- the charger is with 0.1-0.005% weight concentration and glass powder with at 5% weight concentration to enhance adhesion.
- the charger is with 0.01% weight concentration.
- the cathode plate 1 and the anode plate 2 are placed in the electrophoresis tank 6 with 3-5 cm separation therebetween.
- the power source 3 provides a DC or a DC pulse voltage to the anode strip with 120V or 100-300V and with pulse frequency of 250 Hz.
- the signal 5 sends a continuous square-wave signal to the controller 4 acting as a signal amplifier.
- the controller 4 amplifies the continuous square-wave signal and sends the amplified continuous square-wave signal to the first one of the cathode strips 11 , while the remaining cathode strips 11 are not conducted. Therefore, an electrical field is established between the first cathode strip 11 and the first anode strip 21 due to a potential difference.
- a carbon nanotube can be fabricated on the position to be deposited with electron emission source on the first cathode strip 11 .
- the remaining cathode strips 11 are conducted one by one and other cathode strips 11 are not conducted. In this manner, the electron emission source can be fabricated.
- the duty cycle for the cathode strips 11 are 1/32 (frequency 32 Hz) or higher frequency provided that the electrophoresis deposition time period is 1 second.
- the electrophoresis deposition is 10 minutes and an electron emission source with 5-10 um thickness can be formed by one electrophoresis deposition operation.
- the signal generator 5 generates a signal to a plurality of signal amplifiers, where one of the signal amplifiers does not provide signal amplification. Therefore, the first cathode strip 11 is in low level while other cathode strips 11 are in high level, which level is the same as that of anode strips 21 .
- An electrical field is present in the first cathode strip 11 and the anode plate 2 such that carbon nanotube will be formed on the first cathode strip 11 and can be formed on other cathode strips 11 successively.
- the signal generator 5 When the controller 4 is timing switch, the signal generator 5 generates a continuous square wave signal to a plurality of timing switches, where the first timing switch is turned on and the remaining timing switches are turned off. Thereof, the first cathode strip 11 is conducted and an electrical field is present in the first cathode strip 11 and the anode plate 2 . A carbon nanotube will be formed on the first cathode strip 11 .
- the first timing switch When the electrophoresis deposition is performed, the first timing switch counts the deposition time. After a predetermined time period is over, the first timing switch is turned off and the second timing switch is turned on, while other timing switches are turned off. In this manner, the carbon nanotube will be formed on the remaining cathode strip 11 successively.
- the scanning-matrix type electrophoresis deposition method according to the present invention has following advantages:
- the electrophoresis deposition method can be used for solution with complicated composition. The distribution is good and various particles can be effectively deposited.
- the electrical field intensity can be increased for a unitary electrophoresis deposition area.
Abstract
A method sequentially performs electrophoresis depositing carbon nanotube of field emission display. Only one cathode strip is subjected to electrical field at one time during electrophoresis deposition. Therefore, the electrophoresis deposition is confined to local area. A cathode plate includes a plurality of cathode strips and the cathode strips sequentially have potential difference with respect to the anode strips, whereby only one electrical field is present for one pixel at one time and carbon nanotube is formed at that pixel. The cathode strips are sequentially applied with voltage for global electrophoresis deposition.
Description
- 1. Field of the Invention
- The present invention relates to a method for electrophoresis depositing carbon nanotube on cathode strip for a field emission display, especially to a method for electrophoresis depositing carbon nanotube with certain powders such as glass powder or conductive powder.
- 2. Description of Prior Art
- The field emission display uses cathode electron emitter to generate electron by electrical field. The emitted electron excites phosphor on anode plate for illumination. The field emission display has compact size and flexible viewable area. The field emission display does not have view angle problem encountered in LCD.
- Conventional triode field emission display includes an anode structure and a cathode structure. There is a spacer disposed between the anode structure and the cathode structure, thereby providing a space and a support for the vacuum region between the anode structure and the cathode structure. The anode structure includes an anode substrate, an anode conducting layer, and a phosphorus layer. The cathode structure includes a cathode substrate, a cathode conducting layer, an electron emission layer, a dielectric layer and a gate layer. The gate layer provides a voltage difference to induce the emission of electrons from the electron emission layer. The conducting layer of the cathode structure provides a high voltage to accelerate the electron beam, such that the electron beam can have enough kinetic energy to impinge and excite the phosphorous layer on the anode structure, thereby emitting light. Accordingly, in order to maintain the movement of electrons in the field emission display, a vacuum apparatus is required to keep the vacuum degree of the display being below 10−5 torr. Therefore, the electrons can have appropriate mean free paths. Meanwhile, the pollution and toxication of the electron emission source and the phosphorous layer should be prevented from happening. Furthermore, in order for the electrons to accumulate enough energy to impinge the phosphorous powder, a predetermined gap is required between the two substrates. Consequently, the electrons can be accelerated to impinge the phosphorous layer, thereby exciting the phosphorous layer and emitting light therefrom.
- The electron emission layer is composed of carbon nanotubes. Since carbon nanotubes, proposed by Iijima in 1991 (Nature, 354, 56 (1991)), possess very good electronic properties that can be used to build a variety of devices. The carbon nanotubes also has a very large aspect ratio, mostly larger than 500, and a very high rigidity of Young moduli larger than 1000 GPn. In addition, the tips or defects of the carbon nanotubes are of atomic scale. The properties described above are considered an ideal material for building electron field emitter, such as an electron emission source of a cathode structure of a field emission display. Since the carbon nanotubes comprise the physical properties described above, a variety of manufacturing process can be developed, e.g. screen printing, or thin film processing.
- However, the art of manufacturing the cathode structure employs carbon nanotubes as an electron emission material, which is fabricated on the cathode conducting layer. The manufacturing process can employ chemical vapor deposition (CVD) process, or any kind of process that can pattern the photosensitive carbon nanotube solution on any pixel of the cathode conducting layer. Moreover, the cathode structure can also be manufactured by coating the carbon nanotubes solution while incorporating with a mask, or depositing the carbon nanotubes on the cathode conducting layer by an electrophoresis method. However, it is still difficult to fabricate carbon nanotube in the cathode electrode in each pixel by above-mentioned processes. Especially for large-size FED display.
- Recently, an electrophoresis deposition process is proposed, for example, US pre-grant publication No. 2003/0102222 discloses an electrophoresis deposition process. An alcohol suspension for carbon nanotube is prepared and charger such as Mg, La, Y and Al is used to form an electrophoresis solution. The cathode electrode substrate to be deposited is connected to an electrode in the electrophoresis solution. A DC or AC voltage is applied to provide electrical field in the electrophoresis solution. The charger is dissolved in the electrophoresis solution and attached to the carbon nanotube powder. The electrical field will facilitate the carbon nanotube powder to deposit on an electrode. This electrophoresis deposition process can easily deposit the carbon nanotube on the electrode layer without the limit of forming triode field emission display on electrode. Therefore, the electrophoresis deposition process is extensively used on the fabrication of cathode plate.
- Moreover, the applicant of the present invention had also proposed a pulse electrophoresis deposition process to enhance uniformity of carbon nanotube. The deposition amount in unitary area is enhanced and the process can be used for aqueous solution. However, the current pulse electrophoresis deposition process still have following problems.
- 1. The area electrophoresis is difficult for electrophoresis solution with complicated carbon nanotube suspension. Some particles are added to the electrophoresis solution to enhance the adhesion ability of carbon nanotube and the effect of manufacturing electron emission source. The carbon nanotube suspension is sensitive to electrical field distribution, and to concentration and thickness of the display. This problem is more serous for large-size display.
- 2. The pulse electrophoresis deposition process has good effect for aqueous solution. However, the property of solution is critical to some carbon nanotube. For example, some non-aqueous solution such as alcohol solution has good property for most carbon nanotube. However, the pulse electrophoresis deposition process uses larger current and has burning risk for alcohol solution.
- 3. The impedance distribution of cathode strip depends on distribution variation of strip length. Therefore, the impedance variation is serious, especially for large-size display. The end of the cathode strip close to power source encounters larger current and has greater deposition concentration. The electrophoresis deposition is not uniform.
- The present invention is to provide a method for sequentially electrophoresis depositing carbon nanotube of field emission display. In prior art electrophoresis depositing process for large-size anode/cathode plate, the current is large and the deposition is spares. Therefore, the electrophoresis deposition is not uniform for solution with complicated composition. In the present invention, the electrophoresis deposition is localized to one single cathode strip at one time. The complicated particles in the solution is deposited on the single cathode strip, and the remaining cathode strips are conducted successively and individually for global electrophoresis deposition.
- Accordingly, the present invention provides a method for sequentially electrophoresis depositing carbon nanotube of field emission display. The anode ends of a power source are connected to anode strips of an anode plate. The cathode ends of the power source are connected to one input ends of a plurality of controllers. The output ends of the controllers are connected to a plurality of cathode strips of a cathode plate. A signal generator is connected to another input ends of the controllers.
- An electrophoresis tank is provided with electrophoresis solution therein and the anode plate and the cathode plate are placed parallel in the electrophoresis tank. The voltages from anode ends of the power source is output to the anode strips. The signal generator sends pulse voltage signal to one of the controllers such that one of the cathode strip is conducted while the remaining cathode strips are not conducted, whereby only one electrical field is present for one pixel at one time and carbon nanotube is formed at that pixel. The next cathode strip is conducted successively and the remaining cathode strips are non-conducted to fabricate carbon nanotube electron emission source in sequential manner.
- The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
-
FIG. 1 shows a schematic diagram of the anode plate and cathode plate according to a preferred embodiment of the present invention. -
FIG. 2 shows the schematic diagram of connection of the anode plate and cathode plate to the electrophoresis deposition equipment. -
FIG. 3 shows the schematic diagram of connection of the anode plate and cathode plate to the electrophoresis deposition equipment during fabrication. -
FIG. 4 shows a simplified schematic diagram of connection of the anode plate and cathode plate to the electrophoresis deposition equipment. - With reference to
FIGS. 1 and 2 , in the method for electrophoresis depositing carbon nanotube on cathode strip for a field emission display according to the present invention, sequential electrophoresis deposition localizes current to a single pixel to fabricate carbon nanotube electron emission source. Therefore, the peak current can be reduced and the method can be applied to manufacture of large display. - According to the method of the present invention, a
cathode plate 1 is prepared with a plurality of cathode strips 11 (such as 32 cathode strips). The cathode strips 11 are already formed with gate and semi-finished sacrifice layer. The sacrifice layer is used to prevent unwanted deposition (such as gate, dielectric) on the non-electrophoresis deposition area. The sacrifice layer is removed after electrophoresis deposition process. - Moreover, an
anode plate 2 is prepared and theanode plate 2 is formed by platinum, titanium plate or screen-printing plate. - A
power source 3 is connected to theanode plate 2 by anode ends 31 thereof and is connected to input ends ofcontrollers 4 by cathode ends 32 thereof Thecontroller 4 is connected to the cathode strips 11 by output ends thereof. - Another input end of the
controller 4 is connected to asignal generator 5 to complete the connection for electrophoresis depositing. Thesignal generator 5 provides sequential signal for the cathode strips 11. Thecontroller 4 controls a conducting and an un-conducting state for the cathode strips 11 and can be realized by signal amplifier or switch. The signal amplifier decides to amplify or not to amplify the output signal from thesignal generator 5. A potential difference is present between thecathode strip 11 and the anode plate to provide an electrical field. Therefore, carbon nanotube electron emission source can be fabricated on asingle cathode strip 11. - The above-mentioned switch is a timing switch and conducts a predetermined time period such that the signal generated by the
signal generator 5 is applied to onecathode strip 11. A potential difference is present between thecathode strip 11 and the anode plate to provide an electrical field. Therefore, carbon nanotube electron emission source can be fabricated on asingle cathode strip 11. When the predetermined time period is elapsed, the switch is turned off and a next conduction period is provided for a nextsingle cathode strip 11 for fabricating carbon nanotube electron emission source successively. - With reference to
FIGS. 3 and 4 , after the connection for thecathode plate 1, theanode plate 2, thescanning power source 3, thesignal amplifier 4 and thesignal generator 5 is completed, an electrophoresis solution is prepared for theelectrophoresis tank 6. Alcohol is used for solution and carbon nanotube is used for electron emission source and manufactured by arc discharge. The carbon nanotube has average length below 5 μm and average diameter below 100 nm. The carbon nanotube has multiple wall, the carbon nanotube has an additive concentration of 0.1%-0.005% (preferably 0.02%). The charger uses metal salt is conductive after electrophoresis, for example, the metal salt is one of InCl and indium nitride or other salt with tin. The charger is with 0.1-0.005% weight concentration and glass powder with at 5% weight concentration to enhance adhesion. Preferably the charger is with 0.01% weight concentration. - The
cathode plate 1 and theanode plate 2 are placed in theelectrophoresis tank 6 with 3-5 cm separation therebetween. Thepower source 3 provides a DC or a DC pulse voltage to the anode strip with 120V or 100-300V and with pulse frequency of 250 Hz. Thesignal 5 sends a continuous square-wave signal to thecontroller 4 acting as a signal amplifier. Thecontroller 4 amplifies the continuous square-wave signal and sends the amplified continuous square-wave signal to the first one of the cathode strips 11, while the remaining cathode strips 11 are not conducted. Therefore, an electrical field is established between thefirst cathode strip 11 and the first anode strip 21 due to a potential difference. A carbon nanotube can be fabricated on the position to be deposited with electron emission source on thefirst cathode strip 11. The remaining cathode strips 11 are conducted one by one and other cathode strips 11 are not conducted. In this manner, the electron emission source can be fabricated. The duty cycle for the cathode strips 11 are 1/32 (frequency 32 Hz) or higher frequency provided that the electrophoresis deposition time period is 1 second. The electrophoresis deposition is 10 minutes and an electron emission source with 5-10 um thickness can be formed by one electrophoresis deposition operation. - Alternatively, the
signal generator 5 generates a signal to a plurality of signal amplifiers, where one of the signal amplifiers does not provide signal amplification. Therefore, thefirst cathode strip 11 is in low level while other cathode strips 11 are in high level, which level is the same as that of anode strips 21. An electrical field is present in thefirst cathode strip 11 and theanode plate 2 such that carbon nanotube will be formed on thefirst cathode strip 11 and can be formed on other cathode strips 11 successively. - When the
controller 4 is timing switch, thesignal generator 5 generates a continuous square wave signal to a plurality of timing switches, where the first timing switch is turned on and the remaining timing switches are turned off. Thereof, thefirst cathode strip 11 is conducted and an electrical field is present in thefirst cathode strip 11 and theanode plate 2. A carbon nanotube will be formed on thefirst cathode strip 11. When the electrophoresis deposition is performed, the first timing switch counts the deposition time. After a predetermined time period is over, the first timing switch is turned off and the second timing switch is turned on, while other timing switches are turned off. In this manner, the carbon nanotube will be formed on the remainingcathode strip 11 successively. - To sum up, the scanning-matrix type electrophoresis deposition method according to the present invention has following advantages:
- 1. The electrophoresis deposition method can be used for solution with complicated composition. The distribution is good and various particles can be effectively deposited.
- 2. The electrical field intensity can be increased for a unitary electrophoresis deposition area.
- 3. The cost and electrical current consumption can be reduced for large-size display.
- Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.
Claims (18)
1. A method for sequentially electrophoresis depositing carbon nanotube of field emission display, comprising
connecting anode ends of a power source to anode strips of an anode plate, connecting cathode ends of the power source to one input end of a plurality of controllers, connecting output ends of the controllers to a plurality of cathode strips of a cathode plate, connecting a signal generator to another input end of the controllers;
providing an electrophoresis tank with electrophoresis solution therein and placing the anode plate and the cathode plate parallel in the electrophoresis tank;
outputting voltages from anode ends of the power source to the anode strips, the signal generator sending pulse voltage signal to one of the controllers such that one of the cathode strip is conducted while the remaining cathode strips are not conducted, whereby only one electrical field is present for one pixel at one time and carbon nanotube is formed at that pixel;
conducting next cathode strip successively and keeping the remaining cathode strips being non-conducted to fabricate carbon nanotube electron emission source in sequential manner.
2. The method of claim 1 , wherein the power source provides the anode plate with DC or DC pulse voltage, wherein the voltage is 100-300V and the pulse frequency is 250 Hz.
3. The method of claim 1 , wherein the anode plate can be one of platinum plate, titanium plate or screen-printing plate.
4. The method of claim 1 , wherein the controller is one of amplifier and switch.
5. The method of claim 4 , wherein the switch is a timing switch.
6. The method of claim 1 , wherein the cathode plate has a plurality of cathode strips thereon.
7. The method as in claim 1 , wherein the cathode strip is a semi-finished product with gate and sacrifice layer.
8. The method as in claim 7 , wherein the sacrifice layer is functioned to prevent unwanted deposition such as gate and dielectric layer.
9. The method as in claim 7 , further comprising a step of removing the sacrifice layer.
10. The method as in claim 1 , wherein the cathode plate and the anode plate are placed in the electrophoresis tank parallel with 3-5 cm separation therebetween.
11. The method as in claim 1 , wherein the electrophoresis solution used alcohol as solution, the electron emission source uses powder material made of carbon nanotube formed by arc discharge, the carbon nanotube has average tube length below 5 μm and average diameter below 100 nm and has multiple wall, the carbon nanotube has an additive concentration of 0.1%˜0.005%.
12. The method as in claim 11 , wherein the additive concentration is preferably 0.02%
13. The method as in claim 1 , wherein the solution further comprises chargers, the charger uses metal salt being conductive after electrophoresis.
14. The method as in claim 13 , wherein the metal salt is one of InCl and indium nitride or other salt with tin.
15. The method as in claim 13 , wherein the charger is InCl salt with 0.1-0.005% weight concentration and glass powder with at 5% weight concentration to enhance adhesion.
16. The method as in claim 15 , wherein the charger is preferably with 0.01% weight concentration
17. The method as in claim 1 , wherein the signal generator generates a continuous square wave signal.
18. A method for sequentially electrophoresis depositing carbon nanotube of field emission display, comprising
connecting anode ends of a power source to anode strips of an anode plate, connecting cathode ends of the power source to one input end of a plurality of controllers, connecting output ends of the controllers to a plurality of cathode strips of a cathode plate, connecting a signal generator to another input end of the controllers;
providing an electrophoresis tank with electrophoresis solution therein and placing the anode plate and the cathode plate parallel in the electrophoresis tank;
outputting voltages from anode ends of the power source to the anode strips, the signal generator sending pulse voltage signal sequentially to one of the controllers such that one of the cathode strip is conducted while the remaining cathode strips are not conducted, whereby only one electrical field is present for one pixel at one time and carbon nanotube is formed at that pixel;
conducting next cathode strip successively and keeping the remaining cathode strips being non-conducted to fabricate carbon nanotube electron emission source in sequential manner.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150233971A1 (en) * | 2008-02-19 | 2015-08-20 | West Virginia University Research Corporation | Stimulus responsive nanoparticles |
CN108442101A (en) * | 2018-04-28 | 2018-08-24 | 青岛科技大学 | A kind of large-scale production equipment of carbon nano-tube modification carbon fiber surface |
Citations (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2530546A (en) * | 1946-06-08 | 1950-11-21 | Bell Telephone Labor Inc | Electrophoretic deposition of insulating coating |
US3607696A (en) * | 1968-10-21 | 1971-09-21 | Ibm | Reversible electrophoresis and applications thereof |
US3658676A (en) * | 1970-05-13 | 1972-04-25 | Sherwin Williams Co | Monitoring apparatus and process for controlling composition of aqueous electrodeposition paint baths |
US4824538A (en) * | 1986-12-10 | 1989-04-25 | Toyota Jidosha Kabushiki Kaisha | Method for electrodeposition coating |
US5135628A (en) * | 1989-05-05 | 1992-08-04 | Isco, Inc. | Pulsed field gel electrophoresis of large DNA |
US5754200A (en) * | 1995-12-06 | 1998-05-19 | Nec Corporation | Ink jet type head assembly |
US5830340A (en) * | 1997-03-05 | 1998-11-03 | Trumem International Llc | Method for making a composite filter |
US5914022A (en) * | 1996-01-05 | 1999-06-22 | Lowry; Patrick Ross | Method and apparatus for monitoring and controlling electrodeposition of paint |
US6208321B1 (en) * | 1997-04-03 | 2001-03-27 | Nec Corporation | Electrostatic ink jet recorder having ejection electrodes and auxiliary electrodes divided into groups |
US6231740B1 (en) * | 1996-07-18 | 2001-05-15 | Cosmo Bio Co., Ltd. | Electrophoresis apparatus having an electric controller |
US20010036095A1 (en) * | 1996-07-18 | 2001-11-01 | Akio Ooike | Electrophoresis apparatus with an electric controller and cover |
US6451192B1 (en) * | 1996-07-18 | 2002-09-17 | Cosmo Bio Co., Ltd. | Simplified electrophoresis apparatus |
US20030102222A1 (en) * | 2001-11-30 | 2003-06-05 | Zhou Otto Z. | Deposition method for nanostructure materials |
US20030111946A1 (en) * | 2001-12-18 | 2003-06-19 | Talin Albert Alec | FED cathode structure using electrophoretic deposition and method of fabrication |
US6616497B1 (en) * | 1999-08-12 | 2003-09-09 | Samsung Sdi Co., Ltd. | Method of manufacturing carbon nanotube field emitter by electrophoretic deposition |
US20030190772A1 (en) * | 2002-03-27 | 2003-10-09 | Motohiro Toyota | Cold cathode field emission device and process for the production thereof, and cold cathode field emission display and process for the production thereof |
US20040023514A1 (en) * | 2002-08-01 | 2004-02-05 | Semiconductor Energy Laboratory Co., Ltd. | Method of manufacturing carbon nonotube semiconductor device |
US6864110B2 (en) * | 2002-10-22 | 2005-03-08 | Agilent Technologies, Inc. | Electrophoretic processes for the selective deposition of materials on a semiconducting device |
US20060054491A1 (en) * | 2001-09-25 | 2006-03-16 | International Center For Materials Research | Carbon nanotubes and method of manufacturing same, electron emission source, and display |
US20060217025A1 (en) * | 2005-03-28 | 2006-09-28 | Teco Nanotech Co., Ltd. | Method for enhancing homogeneity of carbon nanotube electron emission source made by electrophoresis deposition |
US20060249388A1 (en) * | 2005-05-04 | 2006-11-09 | Yu-Yang Chang | Electrophoretic deposition method for a field emission device |
US7220971B1 (en) * | 2004-12-29 | 2007-05-22 | The University Of North Carolina At Chapel Hill | Multi-pixel electron microbeam irradiator systems and methods for selectively irradiating predetermined locations |
US20070145335A1 (en) * | 2003-09-25 | 2007-06-28 | Fuji Xerox Co., Ltd. | Composite and method of manufacturing the same |
US20070187245A1 (en) * | 2006-02-16 | 2007-08-16 | Teco Electric & Machinery Co., Ltd. | Method for fabricating nanotube electron emission source by scanning-matrix type electrophoresis deposition |
US20070187246A1 (en) * | 2006-02-16 | 2007-08-16 | Teco Electric & Machinery Co., Ltd. | Method of manufacturing carbon nanotube electron field emitters by dot-matrix sequential electrophoretic deposition |
-
2006
- 2006-03-17 US US11/377,419 patent/US20070215473A1/en not_active Abandoned
Patent Citations (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2530546A (en) * | 1946-06-08 | 1950-11-21 | Bell Telephone Labor Inc | Electrophoretic deposition of insulating coating |
US3607696A (en) * | 1968-10-21 | 1971-09-21 | Ibm | Reversible electrophoresis and applications thereof |
US3658676A (en) * | 1970-05-13 | 1972-04-25 | Sherwin Williams Co | Monitoring apparatus and process for controlling composition of aqueous electrodeposition paint baths |
US4824538A (en) * | 1986-12-10 | 1989-04-25 | Toyota Jidosha Kabushiki Kaisha | Method for electrodeposition coating |
US5135628A (en) * | 1989-05-05 | 1992-08-04 | Isco, Inc. | Pulsed field gel electrophoresis of large DNA |
US5754200A (en) * | 1995-12-06 | 1998-05-19 | Nec Corporation | Ink jet type head assembly |
US5914022A (en) * | 1996-01-05 | 1999-06-22 | Lowry; Patrick Ross | Method and apparatus for monitoring and controlling electrodeposition of paint |
US6231740B1 (en) * | 1996-07-18 | 2001-05-15 | Cosmo Bio Co., Ltd. | Electrophoresis apparatus having an electric controller |
US20010036095A1 (en) * | 1996-07-18 | 2001-11-01 | Akio Ooike | Electrophoresis apparatus with an electric controller and cover |
US6451192B1 (en) * | 1996-07-18 | 2002-09-17 | Cosmo Bio Co., Ltd. | Simplified electrophoresis apparatus |
US5830340A (en) * | 1997-03-05 | 1998-11-03 | Trumem International Llc | Method for making a composite filter |
US6208321B1 (en) * | 1997-04-03 | 2001-03-27 | Nec Corporation | Electrostatic ink jet recorder having ejection electrodes and auxiliary electrodes divided into groups |
US6616497B1 (en) * | 1999-08-12 | 2003-09-09 | Samsung Sdi Co., Ltd. | Method of manufacturing carbon nanotube field emitter by electrophoretic deposition |
US20060054491A1 (en) * | 2001-09-25 | 2006-03-16 | International Center For Materials Research | Carbon nanotubes and method of manufacturing same, electron emission source, and display |
US20030102222A1 (en) * | 2001-11-30 | 2003-06-05 | Zhou Otto Z. | Deposition method for nanostructure materials |
US7252749B2 (en) * | 2001-11-30 | 2007-08-07 | The University Of North Carolina At Chapel Hill | Deposition method for nanostructure materials |
US20030111946A1 (en) * | 2001-12-18 | 2003-06-19 | Talin Albert Alec | FED cathode structure using electrophoretic deposition and method of fabrication |
US20030190772A1 (en) * | 2002-03-27 | 2003-10-09 | Motohiro Toyota | Cold cathode field emission device and process for the production thereof, and cold cathode field emission display and process for the production thereof |
US20040023514A1 (en) * | 2002-08-01 | 2004-02-05 | Semiconductor Energy Laboratory Co., Ltd. | Method of manufacturing carbon nonotube semiconductor device |
US6864110B2 (en) * | 2002-10-22 | 2005-03-08 | Agilent Technologies, Inc. | Electrophoretic processes for the selective deposition of materials on a semiconducting device |
US20070145335A1 (en) * | 2003-09-25 | 2007-06-28 | Fuji Xerox Co., Ltd. | Composite and method of manufacturing the same |
US7220971B1 (en) * | 2004-12-29 | 2007-05-22 | The University Of North Carolina At Chapel Hill | Multi-pixel electron microbeam irradiator systems and methods for selectively irradiating predetermined locations |
US20060217025A1 (en) * | 2005-03-28 | 2006-09-28 | Teco Nanotech Co., Ltd. | Method for enhancing homogeneity of carbon nanotube electron emission source made by electrophoresis deposition |
US20060249388A1 (en) * | 2005-05-04 | 2006-11-09 | Yu-Yang Chang | Electrophoretic deposition method for a field emission device |
US20070187245A1 (en) * | 2006-02-16 | 2007-08-16 | Teco Electric & Machinery Co., Ltd. | Method for fabricating nanotube electron emission source by scanning-matrix type electrophoresis deposition |
US20070187246A1 (en) * | 2006-02-16 | 2007-08-16 | Teco Electric & Machinery Co., Ltd. | Method of manufacturing carbon nanotube electron field emitters by dot-matrix sequential electrophoretic deposition |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150233971A1 (en) * | 2008-02-19 | 2015-08-20 | West Virginia University Research Corporation | Stimulus responsive nanoparticles |
US9658251B2 (en) * | 2008-02-19 | 2017-05-23 | West Virginia University | Stimulus responsive nanoparticles |
CN108442101A (en) * | 2018-04-28 | 2018-08-24 | 青岛科技大学 | A kind of large-scale production equipment of carbon nano-tube modification carbon fiber surface |
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