JP2005246507A - Device for arranging material to tip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for arranging a material to the tips by which a material is accurately and uniformly arranged to all of the tips of a plurality of protrusions. <P>SOLUTION: A catalyst arranging device 30 is a device for arranging a material constituting the catalyst 3 to all of the tips of a plurality of emitter chips 1 formed to a substrate 2. The substrate 2 and the emitter chips 1 are held by a holding part 4 and maintained at a temperature higher than the melting point of the catalyst 3 by a heater 4a. A drive mechanism 6 is controlled by a controller 9 and accurately changes the distance between the substrate 2 and the catalyst 3 by controlling the holding parts 4, 5 while maintaining a parallel state of the substrate 2 and the catalyst 3. The drive mechanism 6 is moved so that only the tips of the emitter chips 1 are brought into contact with the catalyst 3 and the tips of the emitter chips 1 are quickly separated from the catalyst 3 after the contact. At that time, the catalyst 3 is melted by the contact with the emitter chips 1 whose temperature is set to exceed the melting point of the catalyst 3 by a heater 5. The melted catalyst 3 is transferred only to the tips of the emitter chips 1. Hence, the catalyst 3 is uniformly and accurately arranged to all of the tips of a plurality of the emitter chips 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a substance arrangement device at a tip part that arranges substances at a plurality of tip parts, and a substance arrangement method at the tip part.

  A technique is known in which a substance such as a catalyst is arranged on a plurality of protrusions such as emitter chips formed on the surface of a substrate. Carbon nanotubes are selectively grown on the portion where the catalyst is disposed on the emitter tip by using a plasma CVD method or the like.

  As a technique for disposing a catalyst on the emitter chip described above, for example, Non-Patent Document 1 discloses an emitter in which an electric field is concentrated by disposing a catalyst on the entire surface of the emitter chip and performing CVD while applying an electric field in a direction perpendicular to the substrate. A technique for selectively growing carbon nanotubes at the tip of the chip is described. Non-Patent Document 2 discloses a technique for selectively growing a carbon nanotube at a desired position on an emitter chip by using a focused ion beam (FIB). Has been described.

  However, since the technique described in Non-Patent Document 1 uses electric field concentration, there is a case where dust or the like adheres to a part other than the emitter tip and the carbon nanotube growth becomes unstable. In the technique described in Non-Patent Document 2, it is difficult to focus the focused ion beam on the tip portions of a plurality of emitter tips one by one, and it may take a lot of time.

Takahito Ono et al., "Electric-field-enhanced growth of carbon nanotubes for scanning probe microscopy", Nanotechnology, 13 (2002) 62-64 D. Ferrrer et al., "Carbon Nanotubes Growth on Nickel Implanted Nanopyramids Array (NPA)", 9th international conference on the formation of semiconductor interfaces, Madrid, September 15-19, 2003

  Examples of problems to be solved by the present invention include the above. This invention makes it a subject to provide the substance arrangement | positioning apparatus to the front-end | tip part which can arrange | position a substance accurately and uniformly to all the front-end | tip parts of several protrusion part.

  The invention according to claim 1 is an apparatus for disposing a substance on the tip, wherein the first holding means for holding a first flat plate having a plurality of sharp protrusions on the surface, and the first A second holding means for holding a second flat plate formed of a material having a lower melting point than the material constituting the flat plate in parallel with the first flat plate, and the first flat plate, Only the first heater that maintains a temperature equal to or higher than the melting point of the material constituting the second flat plate and the tip of the protruding portion are brought into contact with the second flat plate, and immediately after the contact, the tip of the protruding portion Control means for controlling the distance between the first holding means and the second holding means so as to be separated from the second flat plate.

  The invention according to claim 10 is a method of disposing a substance on the tip, and comprises a step of holding a first flat plate having a plurality of protrusions with sharp tips on the surface, and the planar member. A step of holding a second flat plate formed of a material having a lower melting point than the material to be held in parallel with the first flat plate, and a material constituting the second flat plate. Maintaining the temperature at a temperature equal to or higher than the melting point, and contacting only the tip of the protrusion with the second flat plate, and immediately after the contact, the tip of the protrusion is separated from the second flat plate. And a control step of controlling a distance between the first flat plate and the second flat plate.

  In a preferred embodiment of the present invention, the device for disposing a substance on the tip portion includes a first holding means for holding a first flat plate having a plurality of sharp protrusions on the surface, and the first flat plate. Second holding means for holding a second flat plate formed of a material having a lower melting point than the material constituting the first flat plate in parallel with the first flat plate, and the first flat plate, the second flat plate. The first heater that maintains a temperature equal to or higher than the melting point of the material constituting the flat plate, and only the tip of the protrusion are brought into contact with the second flat plate, and immediately after the contact, the tip of the protrusion is Control means for controlling a distance between the first holding means and the second holding means so as to be separated from the second flat plate.

  In the above-described material placement device on the tip, the material constituting the second flat plate is placed on all the tips of the plurality of protrusions formed on the first flat plate at once (hereinafter also referred to as “attachment”). ). The first flat plate is held by the first holding means, and the second flat plate is held by the second holding means. The first flat plate and the projecting portion are maintained at a temperature equal to or higher than the melting point of the material constituting the second flat plate by the first heater. The control means accurately changes the distance between the first holding means and the second holding means while maintaining the first flat plate and the second flat plate in a parallel state. This control means moves so that only the tip of the protrusion formed on the first flat plate contacts the second flat plate, and immediately after the contact, the tip of the protrusion and the second flat plate are moved. Separate. At this time, the second flat plate is melted by the contact of the projecting portion made higher than the melting point of the second flat plate by the first heater. Thereby, the substance which comprises the fuse | melted 2nd flat plate transfers only to the front-end | tip part of a protrusion part. Therefore, the substance which comprises a 2nd flat plate can be arrange | positioned with sufficient precision to all the front-end | tip parts of a some protrusion part.

  In one aspect of the substance disposing device at the tip, the second flat plate is provided with a second heater that maintains a temperature lower than the melting point of the material constituting the second flat plate. Since the second flat plate is maintained at a temperature lower than its melting point by the second heater, it maintains a solid state. Since the second flat plate is not unnecessarily melted or sublimated by bringing the protrusions into contact with the second flat plate in such a state, the second flat plate is not provided at the tip of the protruding portion. The substance which comprises is not arrange | positioned.

In another aspect of the device for arranging a substance on the tip, the second holding means has a flat surface, the second flat plate is arranged on the flat layer, and the film thickness is the first thickness. The thin film is constant in the region in contact with the flat plate. The second holding means has a flat surface with a flat surface facing the first flat plate. Further, the second flat plate is a thin film having a constant thickness in a region in contact with the first flat plate. In this case, the tip of the protrusion comes into contact with the second flat plate, and at the same time, the tip of the protrusion comes into contact with the flat surface. That is, even if the protruding portion comes into contact with the flat surface, only the tip of the protruding portion is in contact with the second flat plate. Therefore, since the change of the distance between the first flat plate and the second flat plate by the control means may be stopped when the projecting portion comes into contact with the flat surface, the distance between the first flat plate and the second flat plate is controlled. Becomes easier. That is, the control means does not need to accurately control the distance between the second flat plate and the protruding portion.
In another aspect of the device for disposing a substance on the tip, the space between the protruding portion and the second flat plate is maintained in a high-pressure atmosphere of an inert gas. Thereby, the second flat plate is sublimated by heat at the time of contact of the protruding portion or heat of the first flat plate (including radiation heat), and the sublimated second flat plate is solidified at a place other than the tip portion of the protruding portion. This can be prevented. Further, oxidation of the second flat plate and the protruding portion can be prevented in a series of steps when the second flat plate is arranged on the protruding portion.

  In another aspect of the device for disposing a substance on the tip portion, a device for allowing an inert gas to flow into a space between the protruding portion and the second flat plate is provided. Also by this, the second flat plate is sublimated by the heat at the time of contact of the protruding portion or the heat of the first flat plate (including radiant heat), and the sublimated second flat plate is solidified at a place other than the tip portion of the protruding portion. This can be prevented. Further, oxidation of the second flat plate and the protruding portion can be prevented in a series of steps when the second flat plate is arranged on the protruding portion. Furthermore, in this case, since a high-pressure inert gas may be prepared in advance and flowed into the apparatus, it is not necessary to separately provide an apparatus for maintaining the inside of the apparatus in a high-pressure atmosphere of inert gas.

  In the substance disposing apparatus at the tip portion, preferably, in the first heater, the temperature of the first flat plate maintains the melting point of the second flat plate within a predetermined temperature range. This is because, as the temperature of the first flat plate is higher, the process of arranging the material constituting the second flat plate in the projecting portion is completed in a shorter time, but the radiant heat to the second flat plate is caused by the temperature being too high. This is because the sublimation of the second flat plate may be induced by, for example.

  Further preferably, the control means includes the first holding means and the second holding means so that a time during which the projecting portion and the second flat plate are in contact with each other is a predetermined time. Control the contact time. Thereby, since a protrusion part contacts a 2nd flat plate only for predetermined time, a 2nd flat plate does not melt | dissolve or sublime a lot by the heat | fever of a protrusion part. Thereby, it is possible to prevent the substance constituting the second flat plate from adhering to a place other than the tip of the protrusion.

  Further preferably, the pressure at the time of contact between the first flat plate or the protruding portion and the distance acquisition means for acquiring the distance between the second flat plate and the protruding portion and the second flat plate is preferably set. Pressure acquiring means for acquiring, and the control means controls the distance between the first holding means and the second holding means based on the distance and the pressure. The control means controls the distance between the first flat plate and the second flat plate based on the information acquired from the plurality of distance acquisition means and the pressure acquisition means, so that the leading ends of the plurality of protrusions can be accurately second. A flat plate can be contacted. Therefore, it becomes possible to arrange | position the substance which comprises a 2nd flat plate uniformly to all the front-end | tip parts of a some protrusion part.

  Further preferably, the first flat plate is a substrate, the projecting portion is an emitter tip, the second flat plate is a catalyst, and the substance arranging device on the tip portion is a tip of the emitter tip. The catalyst is disposed in the part. The substance placement device at the tip can be a catalyst placement device that places the catalyst accurately and evenly at all the tips of the plurality of fine emitter chips. Carbon nanotubes and the like can be selectively grown with high accuracy from the catalyst disposed at the tip of the fine emitter tip.

  In another aspect of the present invention, the method of disposing a substance on the tip includes a step of holding a first flat plate having a plurality of protrusions with sharp tips on the surface, and a material constituting the planar member. A step of holding a second flat plate formed of a material having a low melting point so as to face the first flat plate in parallel with the first flat plate, and a melting point of the material constituting the second flat plate. Maintaining the temperature of the first and second protrusions so that only the tip of the protrusion is in contact with the second flat plate, and immediately after the contact, the tip of the protrusion is separated from the second flat plate. A control step of controlling a distance between the first flat plate and the second flat plate. Even in such a material arrangement method on the tip portion, as described above, the substance constituting the second flat plate can be arranged with high precision evenly on all the tip portions of the plurality of protrusions.

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

  A catalyst placement device 30 which is an embodiment of the material placement device at the tip according to the present invention will be described with reference to FIGS. 1 and 2. In FIG. 1, schematic structure of the catalyst arrangement | positioning apparatus 30 which concerns on the Example of this invention is shown.

  The catalyst arrangement device 30 includes a holding unit 4 that holds the substrate 2 on which the emitter chip 1 is formed, a holding unit 5 that holds the catalyst 3, heaters 4a and 5a, a drive mechanism 6, and temperature sensors 7 and 8. And a controller 9.

  The substrate 2 is a substrate made of a material such as silicon. The substrate 2 functions as a first flat plate in the catalyst arrangement device 30. Further, the substrate 2 functions as a cathode (cold cathode) to which a voltage is applied when applied to, for example, an electron-emitting device. A plurality of emitter chips 1 are formed on the surface of the substrate 2.

  A plurality of emitter chips 1 are formed on the surface of the substrate 2 two-dimensionally (in the horizontal direction and in the vertical direction) and have a substantially conical shape. The emitter chip 1 functions as a protrusion formed on the first flat plate in the catalyst arrangement device 30. As a material used for the emitter chip 1, besides the same silicon (Si) as the substrate 2, molybdenum (Mo), niobium (Nb), hafnium (Hf), vanadium (V), platinum (Pt), titanium (Ti), Chromium (Cr) or the like can be used.

  The catalyst 3 is a substance that is disposed on the emitter tip 1 (hereinafter also referred to as “attachment”). The catalyst 3 forms a flat plate having an appropriate thickness, and its surface is polished so as to have high flatness. In this embodiment, when the catalyst 3 is disposed on the emitter chip 1, all the emitter chips 1 are brought into contact with the catalyst 3 at a time while keeping the catalyst 3 and the substrate 2 in parallel. In order to uniformly attach the catalyst 3 only to the tip portions of the plurality of emitter chips 1, the surface of the catalyst 3 is polished so as to have high flatness as described above.

  Further, in this embodiment, the catalyst 3 is brought into contact with the heated tip of the emitter chip 1 to melt the catalyst 3 by the heat of the emitter chip 1, and the catalyst 3 is transferred only to the tip of the emitter chip 1. Put on. Therefore, the emitter tip 1 is maintained at a temperature equal to or higher than the melting point of the catalyst 3. Therefore, it is necessary to use a material lower than the melting point of the material used for the emitter tip 1 for the catalyst 3. For example, when silicon (Si) is used for the emitter chip 1, the melting point is about 1412 ° C., so that zinc (Zn) having a melting point of about 419 ° C. can be used as the catalyst 3. Further, when molybdenum (Mo) is used for the emitter chip 1, the melting point is about 2620 ° C., so nickel (Ni), iron (Fe), cobalt (Co), or the like can be used as the catalyst 3. Thus, the catalyst 3 functions as a second flat plate in the catalyst placement device 30.

  By disposing the catalyst 3 at the tip of the emitter tip 1 as described above, carbon nanotubes can be selectively grown from the tip of the emitter tip 1 with high accuracy by a method such as plasma CVD. A carbon nanotube (not shown) functions as an electron beam source that emits electrons by an electron-emitting device or the like.

  The holding unit 4 holds the substrate 2. The holding unit 4 is provided with a heater 4 a on the surface opposite to the surface that holds the substrate 2. The holding unit 4 functions as a first holding unit. The heater 4a heats the substrate 2 and maintains the temperature to be set. The heater 4 functions as a first heater in the catalyst arrangement device 30. The heater 4 is driven by a control signal S15 from the controller 9.

  The holding unit 5 holds the catalyst 3. The holding unit 5 is provided with a heater 5a on the surface opposite to the surface holding the catalyst. The holding unit 5 functions as a second holding unit. The heater 5a heats the catalyst 3 and maintains the temperature to be set. The heater 5 a functions as a second heater in the catalyst arrangement device 30. The heater 5a is driven by a control signal S16 from the controller 9.

  A specific example of the set temperatures of the heaters 4a and 5a will be described later.

  The temperature sensor 7 is provided on the heater 4a and detects the temperature of the heater 4a. The temperature sensor 8 is provided on the heater 5a and detects the temperature of the heater 5a. Electrical signals S11 and S12 corresponding to the detected temperatures of the temperature sensors 7 and 8 are output to the controller 9.

  The drive mechanism 6 is a device that can change the distance between the substrate 2 and the catalyst 3. The drive mechanism 6 changes the distance between the substrate 2 and the catalyst 3 by moving the holding parts 4 and 5 perpendicularly to the catalyst 3 as indicated by an arrow 51 in FIG. At this time, the drive mechanism 6 changes the distance with high accuracy so that the surface of the substrate 2 and the surface of the catalyst 3 are maintained in a parallel state. The drive mechanism 6 is driven by a control signal S13 from the controller 9.

  The controller 9 mainly performs control in the catalyst arrangement device 30. The controller 9 includes a CPU, ROM, RAM, A / D converter, etc. (not shown). In this embodiment, the controller 9 controls the heaters 4a and 5a and the drive mechanism 6 based on output signals S11 and S12 from the temperature sensors 7 and 8 corresponding to the temperatures of the heaters 4a and 5a. Specifically, the controller 9 controls the heaters 4a and 5a to have a temperature to be set by control signals S15 and S16 supplied to the heaters 4a and 5a. The controller 9 controls the distance between the holding unit 4 and the holding unit 5 by a control signal S13 supplied to the drive mechanism 6. In this case, the controller 9 functions as control means for controlling the distance between the substrate 2 (first flat plate) and the catalyst 3 (second flat plate) by controlling the distance between the holding portions 4 and 5.

  Next, a specific method for arranging the catalyst 3 on the emitter tip 1 will be described with reference to FIG. FIG. 2 is a diagram showing extracted components in the vicinity of the emitter tip 1 and the catalyst 3, respectively.

  As shown in FIG. 2A, the drive mechanism 6 controls the holding portions 4 and 5 to maintain the parallel state of the surface of the catalyst 3 and the surface of the substrate 2 while keeping the substrate 2 on the surface of the catalyst 3. Move vertically. At this time, the substrate 2 is maintained at a temperature equal to or higher than the melting point of the catalyst 3 by the heater 4a. Further, the catalyst 3 is maintained at a temperature at which the catalyst 3 does not exceed the melting point by the heater 5a. That is, the catalyst 3 is maintained in a solid state.

  FIG. 2B shows a state when the emitter tip 1 on the substrate 2 is in contact with the catalyst 3. As shown, only the tip of the emitter tip 1 contacts the catalyst 3. At this time, the controller 9 controls the drive mechanism 6 so that only the tip of the emitter tip 1 contacts the catalyst 3 and the emitter tip 1 is not inserted deeply into the catalyst 3. Further, the controller 9 controls the drive mechanism 6 so that the emitter tip 1 is separated from the catalyst 3 when the emitter tip 1 contacts the catalyst 3 for a predetermined time. This is because when the emitter tip 1 and the catalyst 3 are in contact with each other for a long time, the catalyst 3 is dissolved in a large amount by the heat of the emitter tip 1 and adheres to a place other than the tip of the emitter tip 1 (including the substrate 2). It is because there is a case where it ends up. The predetermined time depends on the temperature at which the heaters 4 and 5 are set, but is determined by the controller 9 within a range of approximately 0.1 to 10 seconds.

  FIG. 2C is a view showing a state where the substrate 2 is separated after the emitter tip 1 is in contact with the catalyst 3. As shown in the drawing, the catalyst 3 is disposed only at the tip of the emitter tip 1 as indicated by reference numeral 11. This is because the emitter chip 1 is set to a temperature equal to or higher than the melting point of the catalyst 3 by the heater 4, so that the catalyst 3 is melted by the contact of the emitter chip 1 and the catalyst 3 is transferred only to the tip of the emitter chip 1. Because. Since the catalyst 3 is maintained at a temperature lower than the melting point by the heater 5 and is kept in a solid state, the catalyst 3 does not sublime or a portion where the emitter chip 1 does not contact is not melted. Therefore, the catalyst 3 does not adhere to any place other than the tip of the emitter tip 1. Further, as described above, since the emitter tip 1 contacts the catalyst 3 only for a predetermined time, the catalyst 3 is not dissolved or sublimated in a large amount by the heat of the emitter tip 1. This also prevents the catalyst 3 from adhering to a place other than the tip of the emitter tip 1. Further, the catalyst 3 is formed so as to have a high flatness, and the drive mechanism 6 moves the substrate 2 with high accuracy while maintaining the parallel state of the substrate 2 and the catalyst 3. The catalyst 3 can be uniformly arranged on the entire tip of the chip 1.

  As described above, in the catalyst arrangement device 30 according to the present embodiment, the catalyst 3 can be accurately arranged only at the tip portion of the emitter chip 1. Moreover, the catalyst 3 can be arrange | positioned with one process with respect to all the emitter tips 1. FIG. Therefore, the placement operation of the catalyst 3 on the emitter tip 1 can be performed in a short time and with high accuracy.

  The substrate 2 is preferably maintained by the heater 4 within a temperature range of about 10 ° C. to about 100 ° C. from the melting point of the catalyst 3. This is because the process of placing the catalyst 3 on the emitter chip 1 is completed in a shorter time as the temperature of the substrate 2 is higher, but sublimation of the catalyst 3 is induced by radiant heat to the catalyst 3 due to the temperature of the substrate 2 being too high. Because there is a case to do.

  The catalyst 3 is preferably maintained by the heater 5 in a temperature range from room temperature to about minus 100 ° C. of the melting point of the catalyst 3. This is because the process of placing the catalyst 3 on the emitter chip 1 is completed in a shorter time when the temperature of the catalyst 3 is higher, but if the catalyst 3 is at a high temperature near the melting point, the sublimation of the catalyst 3 increases and the substrate 2 Alternatively, the catalyst may solidify and adhere to a place other than the tip of the emitter tip 1.

  Next, a catalyst placement device 31 that can place the catalyst 3 more accurately at the tip of the emitter tip 1 will be described with reference to FIG. FIG. 3 is a diagram showing a schematic configuration of a catalyst arrangement device 31 to which new components and the like are added in order to uniformly arrange the catalyst 3 at the tip portions of the plurality of emitter chips 1.

  The catalyst arrangement device 31 includes a holding unit 4, a heater 4 a, a holding unit 5, a heater 5 a, a drive mechanism 6, temperature sensors 7 and 8, a controller 9, a gap sensor 12, and a pressure sensor 13. That is, the catalyst arrangement device 31 is different from the catalyst arrangement device 30 described above in that it includes a gap sensor 12 and a pressure sensor 13.

  A plurality of gap sensors 12 are provided between the substrate 2 and the catalyst 3. The gap sensor 12 includes a high-frequency coil in the sensor, and utilizes the fact that the inductance of the sensor coil changes due to a change in loss due to an eddy current generated in the conductor when an object approaches the sensor electromagnetic field. Thus, a device that detects the distance to the object can be used. The gap sensor 12 according to the present embodiment is used to detect the distance between the substrate 2 or the tip of the emitter chip 1 and the catalyst 3. That is, the gap sensor 12 functions as a distance acquisition unit in the catalyst arrangement device 31. A signal S17 corresponding to the distances detected by the plurality of gap sensors 12 is output to the controller 9.

  A plurality of pressure sensors 13 are provided between the substrate 2 and the catalyst 3. The pressure sensor 13 is a device that can detect pressure with high accuracy, and devices using various principles can be used. In this embodiment, the pressure sensor 13 detects the pressure between the emitter tip 1 and the catalyst 3 when the emitter tip 1 and the catalyst 3 are in contact with each other. That is, the pressure sensor 13 functions as pressure acquisition means in the catalyst placement device 31. A signal S18 corresponding to the pressure detected by the pressure sensor 13 is output to the controller 9.

  The controller 9 controls the distance between the substrate 2 and the catalyst 3 based on the output signal S17 from the gap sensor 12 and the output signal S18 from the pressure sensor 13. Specifically, the controller 9 accurately controls the distance between the emitter tip 1 and the catalyst 3 from the output signals S17 from the plurality of gap sensors 12 when the emitter tip 1 and the catalyst 3 are in contact with each other. Further, the controller 9 manages the parallelism between the substrate 2 and the catalyst 3 from the output signals S17 from the plurality of gap sensors 12. In this case, if the parallelism between the substrate 2 and the catalyst 3 is poor, the setting of the drive mechanism 6 is changed or the surface of the catalyst 3 is polished. On the other hand, the controller 9 controls the distance between the substrate 2 and the catalyst 3 from the output signal S18 from the pressure sensor 13 so that the pressure at the time of contact between the emitter chip 1 and the catalyst 3 does not exceed a predetermined pressure.

  As described above, the controller 9 controls the distance between the substrate 2 and the catalyst 3 based on the detection signals from the plurality of gap sensors 12 and the pressure sensors 13, so that only the tip portions of the plurality of emitter chips 1 are accurately obtained. Since the catalyst 3 can be brought into contact with each other, the catalyst 3 can be arranged uniformly on all the tip portions of the plurality of emitter chips 1.

  Next, a catalyst arrangement method for appropriately preventing the catalyst 3 from adhering to a place other than the tip of the emitter tip 1 will be described with reference to FIG. FIG. 4 is a view showing only the components in the vicinity of the emitter tip 1 and the catalyst 3 extracted.

FIG. 4A shows a catalyst arrangement method in which the inside of a region 15 indicated by oblique lines between the substrate 2 and the catalyst 3 is made an inert gas high-pressure atmosphere, and the catalyst 3 is brought into contact with the tip of the emitter chip 1. Yes. By doing so, the catalyst 3 is sublimated by the heat at the time of contact of the emitter chip 1 or the heat of the substrate 2 (including radiant heat), and the sublimated catalyst is solidified in a place other than the tip of the emitter chip 1. Can be prevented. Further, oxidation of the catalyst 3 and the emitter tip 1 can be prevented in a series of steps when the catalyst 3 is arranged on the emitter tip 1. Note that nitrogen (N ₂ ) or argon (Ar) is preferably used as the inert gas. The high pressure is preferably set to a pressure that satisfies the condition that the mean free path of the atoms constituting the catalyst 3 is smaller than that of the atoms constituting the emitter tip 1 at the above temperature. .

  FIG. 4B shows a catalyst arrangement method in which a high-pressure inert gas flows in the space between the substrate 2 and the catalyst 3 as indicated by an arrow 16 so that the catalyst 3 comes into contact with the tip of the emitter chip 1. ing. In this way, when the catalyst 3 is sublimated by the heat at the time of contact of the emitter chip 1 or the heat of the substrate 2 (including radiant heat), the catalyst 3 that has become gas can flow, so that the sublimated catalyst 3 is Solidification to a place other than the tip of the emitter tip 1 can be prevented. Further, as described above, the oxidation of the catalyst 3 and the emitter tip 1 can be prevented in a series of steps when the catalyst 3 is arranged on the emitter tip 1.

  By doing so, it is possible to prevent the catalyst 3 melted and sublimated by contact with the emitter tip 1 from adhering to a place other than the tip portion of the emitter tip 1 with high accuracy. Therefore, carbon nanotubes can be selectively grown with high accuracy.

[Modification]
Next, a modified example of the catalyst arrangement method according to the present invention will be described with reference to FIG. The catalyst arrangement method according to the modification is greatly different from that described above in that the catalyst arranged on the emitter tip 1 forms a thin film. Note that the basic arrangement of the catalyst arrangement apparatus that executes the catalyst arrangement method according to the modification is the same as that described above. For example, the controller 9 performs the main control of the catalyst placement device. Moreover, the material which comprises the emitter chip 1, the board | substrate 2, and the catalyst 3 with which the catalyst arrangement | positioning apparatus which concerns on a modification is provided uses the thing similar to what was mentioned above.

  As shown in FIG. 5A, the catalyst 18 forms a thin film and is disposed on the buffer layer 20 made of a material having a melting point higher than that of the catalyst 18. The buffer layer 20 is provided on the holding part 5 so that the catalyst 18 forms a highly accurate flatness. When the holding unit 5 itself has a high degree of flatness, a configuration in which the buffer layer 20 is not used may be employed. Also at this time, the substrate 2 is maintained at a temperature equal to or higher than the melting point of the catalyst 3 by the heater 4a. The catalyst 18 is maintained at a solid state by being heated to a temperature that does not exceed the melting point by the heater 5a.

  FIG. 5B shows a state when the emitter tip 1 on the substrate 2 is in contact with the catalyst 18. As shown, the emitter tip 1 is in contact with a thin film catalyst 18. At this time, since the catalyst 18 is a thin film, the tip of the emitter tip 1 contacts the catalyst 18, and at the same time, the tip of the emitter tip 1 also contacts the buffer layer 20. That is, even if the emitter chip 1 is in contact with the buffer layer 20, only the tip of the emitter chip 1 is in contact with the catalyst 3. Thereby, when the emitter chip 1 comes into contact with the buffer layer 20, the movement of the substrate 2 by the drive mechanism 6 may be stopped, so that the controller 9 can easily control the drive mechanism 6. That is, the controller 9 does not need to accurately control the distance between the emitter tip 1 and the catalyst so that the emitter tip 1 is not inserted deeply into the catalyst as described above. The controller 9 controls the drive mechanism 6 so that the emitter tip 1 is separated from the catalyst 18 when the emitter tip 1 contacts the catalyst 18 for a predetermined time.

  FIG. 5C is a view showing a state where the substrate 2 is separated after the emitter tip 1 is brought into contact with the catalyst 18. As shown in the figure, it can be seen that the catalyst 3 is disposed only at the tip of the emitter tip 1 as indicated by reference numeral 22. Even in the catalyst arrangement method according to the modification, the catalyst 18 can be arranged only at the tip portions of the plurality of emitter chips 1.

  The thickness of the thin film of the catalyst 18 is determined according to the amount of the catalyst 18 to be disposed on the emitter chip 1. In this modification, the emitter tip 1 does not enter the catalyst layer to a depth greater than the thickness of the thin film of the catalyst 18. Therefore, in this modification, the amount of the catalyst disposed on the emitter tip 1 can be controlled by controlling the thickness of the thin film of the catalyst 18.

  As described above, since the catalyst 18 according to the modified example forms a thin film, the distance between the catalyst 18 and the emitter chip 1 in the contact of the tip of the emitter chip 1 with the catalyst 18 can be easily controlled. it can. That is, the controller 9 does not need to control the distance between the catalyst 18 and the emitter chip 1 with high accuracy, so that the process for arranging the catalyst can be performed in a short time.

  Also in the catalyst arrangement method according to the modification, the space between the catalyst 18 and the substrate 2 is made an inert gas high-pressure atmosphere, or the inert gas flows between the catalyst 18 and the substrate 2. Is preferred.

  The substance arranging device of the present invention can be applied to, for example, a catalyst arranging device in which a catalyst is arranged at the tip portions of a plurality of emitter chips formed on a substrate. Thus, carbon nanotubes selectively grow with high precision from the catalyst arranged on the emitter tip. The carbon nanotube and the substrate function as components of an electron beam emitting device that can emit electrons at a low voltage. However, application of the present invention is not limited to the above example.

It is a figure which shows schematic structure of the catalyst arrangement | positioning apparatus based on the Example of this invention. It is a figure which shows the procedure which performs the catalyst arrangement | positioning method concerning this invention. It is a figure which shows schematic structure of the catalyst arrangement | positioning apparatus which added the apparatus used in order to arrange | position a catalyst accurately. It is a figure which shows the catalyst arrangement | positioning method which added the method for arranging a catalyst with sufficient precision. It is a figure which shows the procedure which performs the catalyst arrangement | positioning method which concerns on the modification of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Emitter chip 2 Board | substrate 3, 18 Catalyst 4, 5 Holding part 4a, 5a Heater 6 Drive mechanism 7, 8 Temperature sensor 9 Controller 12 Gap sensor 13 Pressure sensor 20 Buffer layer 30, 31 Catalyst arrangement apparatus

Claims (10)

A first holding means for holding a first flat plate having a plurality of protrusions having a sharp tip on the surface;
Second holding means for holding a second flat plate formed of a material having a melting point lower than that of the material constituting the first flat plate, facing the first flat plate in parallel;
A first heater for maintaining the first flat plate at a temperature equal to or higher than the melting point of the material constituting the second flat plate;
Only the tip of the protrusion is brought into contact with the second flat plate, and immediately after the contact, the tip of the protrusion is separated from the second flat plate so as to be separated from the second flat plate. And a control means for controlling the distance from the holding means. 2. The substance disposing device at the tip portion according to claim 1, further comprising a second heater that maintains the second flat plate at a temperature lower than a melting point of a material constituting the second flat plate. . The second holding means has a flat surface, the second flat plate is disposed on the flat surface, and the film thickness is a constant thin film in a region in contact with the first flat plate. The substance arrangement device to the tip according to claim 1 or 2. 4. The substance arrangement device according to claim 1, further comprising means for maintaining a space between the projecting portion and the second flat plate in a high-pressure atmosphere of an inert gas. 5. The substance arranging device according to any one of claims 1 to 3, further comprising means for allowing a high-pressure inert gas to flow into a space between the protruding portion and the second flat plate. The tip according to any one of claims 1 to 5, wherein the temperature of the first flat plate maintains the melting point of the second flat plate within a predetermined temperature range in the first heater. Material placement device to the department. The control means controls a contact time between the first holding means and the second holding means flat plate so that a time during which the protruding portion and the second flat plate are in contact with each other is a predetermined time. The device for arranging a substance on the tip according to any one of claims 1 to 6, Distance acquisition means for acquiring a distance between the first flat plate or the protrusion and the second flat plate;
Pressure acquiring means for acquiring a pressure at the time of contact between the protruding portion and the second flat plate;
8. The control unit according to claim 1, wherein the control unit controls a distance between the first holding unit and the second holding unit based on the distance and the pressure. 9. Material placement device at the tip. The first flat plate is a substrate, the protrusion is an emitter tip, the second flat plate is a catalyst,
9. The substance arranging device at the tip part according to claim 1, wherein the substance arranging device at the tip part arranges the catalyst at a tip part of the emitter tip. On the surface, holding the first flat plate having a plurality of protrusions having a sharp tip,
Holding a second flat plate formed of a material having a melting point lower than that of the material constituting the planar member, facing the first flat plate in parallel, and
Maintaining the first flat plate at a temperature equal to or higher than the melting point of the material constituting the second flat plate;
Only the tip of the protrusion is brought into contact with the second flat plate, and immediately after the contact, the tip of the protrusion is separated from the second flat plate immediately after the contact. And a control step for controlling the distance from the flat plate.

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