US20090314642A1 - Carbon nanotubes bonding on metallic electrodes - Google Patents

Carbon nanotubes bonding on metallic electrodes Download PDF

Info

Publication number
US20090314642A1
US20090314642A1 US12/109,936 US10993608A US2009314642A1 US 20090314642 A1 US20090314642 A1 US 20090314642A1 US 10993608 A US10993608 A US 10993608A US 2009314642 A1 US2009314642 A1 US 2009314642A1
Authority
US
United States
Prior art keywords
electrodes
cnts
carbon nanotubes
dielectrophoresis
wafer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US12/109,936
Inventor
Zhiyin Gan
Sheng Liu
Qiang Lv
Xiaohui Song
Hui Cao
Han Yan
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US12/109,936 priority Critical patent/US20090314642A1/en
Publication of US20090314642A1 publication Critical patent/US20090314642A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
    • H01L23/522—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
    • H01L23/532—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body characterised by the materials
    • H01L23/53204—Conductive materials
    • H01L23/53276—Conductive materials containing carbon, e.g. fullerenes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2221/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof covered by H01L21/00
    • H01L2221/10—Applying interconnections to be used for carrying current between separate components within a device
    • H01L2221/1068—Formation and after-treatment of conductors
    • H01L2221/1094—Conducting structures comprising nanotubes or nanowires
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Definitions

  • the invention relates generally to carbon structures. More particularly, the invention relates to carbon nanotubes bonding on metallic electrodes.
  • the present invention relates to a large scale bonding technology of carbon nanotubes (CNTs) and metallic electrodes. And the invention can help realize wafer level CNTs devices fabrication.
  • CNTs carbon nanotubes
  • metallic electrodes metallic electrodes
  • the bonding was formed by pressing CNTs against the electrodes with a vibrating press at an ultrasonic frequency. Although low resistance contacts between CNTs and metal electrodes can be obtained, the electrodes may be damaged during the bonding process. All these methods have a similar disadvantage from point of view of large scale CNTs devices fabrication for they just bond single device each time. Therefore, in order to realize wide application of CNTs devices, it is necessary to develop large scale bonding technology to satisfy reliable and reproducible large scale CNTs devices fabrication.
  • the present invention is to develop a large scale bonding technology of CNTs and metallic electrodes based on RF induction heating method which allows wafer level CNTs devices fabrication due to non-contact operation and local surface heating.
  • a wafer with number of patterned electrodes is firstly deposited by CNTs via dielectrophoresis method. Then, the wafer is put on the pedestal of our designed induction heating system.
  • the alternating magnetic field derived from the RF source power induces scroll current on the surface of metallic electrodes due to skin effect. In this case, the current will generate Joule heat which could melt the surface metallic electrodes within very short time, and the extent of melting depends on the power and frequency of our RF source and the heating time.
  • the shape of the coil and the type of the electrodes also affect the bonding process.
  • the CNTs will sink into the surface of the electrodes after cooling in vacuum or pretection gas filled environment. As a result, the CNTs on all the electrodes of the wafer are bonded.
  • the invention offers the possibility to realize the wafer level CNTs devices fabrication.
  • FIG. 1 is a system for RF induction heating bonding of CNTs and electrodes.
  • FIG. 2A is a schematic representation of a wafer including patterned electrodes and CNTs placed in RF induction heating winding
  • FIG. 2B is a detail schematic representation of electrodes and CNTs patterned on substrate.
  • FIG. 3A shows an individual carbon nanotube bridges on two isolated electrodes before the RF induction heating bonding.
  • FIG. 3B shows an individual cabon nanotube sinks into the two isolated electrodes after the radioheating bonding process.
  • FIG. 4A is a scanning electron micrograph (SEM) of carbon nanotubes and electrodes after the RF induction heating bonding.
  • FIG. 4B is a SEM of the upsaid electrode in FIG. 4A and the bonded carbon nanotube.
  • FIG. 4C is a SEM of the blow electrode in FIG. 4A and the bonded carbon nanotubes.
  • the electrodes are fabricated by optical lithography and lift-off process.
  • the shape and thickness of the electrodes can vary according to the design of the CNTs device.
  • the CNTs are deposited utilizing dielectrophoresis between pairs of electrodes.
  • the frequency of alternating current in dielectrophoresis is 100 KHz-10 MHz, and the voltage is 1-5V, the time is ranged form 10 second to 30 second.
  • the patterned electrodes and CNTs are shown in FIG. 2B .
  • FIG. 1 shows the RF induction heating bonding system of CNTs and electrodes.
  • the system contains four parts: RF power 11 offers the power of the heating, water cooling system 12 is to cool the winding 13 , and winding 13 is used to induce alternating magnetic field, the glass pedestal 14 supports the wafer during bonding process.
  • RF power 11 offers the power of the heating
  • water cooling system 12 is to cool the winding 13
  • winding 13 is used to induce alternating magnetic field
  • the glass pedestal 14 supports the wafer during bonding process.
  • the structure of winding can be varied according to electrodes patterns in order to obtain uniform heating.
  • the RF current flow along the winding 13 , and generates alternating electric-magnetic field.
  • the glass pedestal 14 is put in the center of the winding 13 .
  • the wafer 15 with patterned metallic electrodes and CNTs are put onto the glass pedestal 14 , as shown in FIG. 2A .
  • the alternating electric-magnetic fields generate whirling current on the surface of the metallic electrodes 16 and create heat to melt the surface metal of the electrodes 16 .
  • the heating time should be not longer than 5 seconds. After natural cooling in vacuum or protection gas filled environment, the CNTs will sink into the electrodes, and the bonding process is finished.
  • the power of the RF source is ranged from 100 W to 500 W, and the frequency is ranged from 200 KHz to 15 MHz, all these parameters depends on the kinds, shape, size and thickness of the metallic electrodes.
  • FIG. 3A and FIG. 3B show the state before and after the RF induction heating bonging process. It is clear that the CNTs sink into the electrodes after the bonding, as shown in FIG. 3B .
  • FIG. 4A is a SEM image of CNTs after the RF induction heating bonding process. The two ends of the CNT sinks into the melting metallic electrode. It is indicated that the CNT is bonded into the electrodes.
  • FIG. 4B shows the upsaid of the electrode shown in FIG. 4A after CNT sinks into it
  • FIG. 4C shows the blow of the electrode shown in FIG. 4B after CNT sinks into it.

Abstract

A method for large scale bonding carbon nanotubes on metallic electrodes is disclosed. The method includes that the wafer with a number of patterned electrodes deposited by CNTs via dielectrophoresis method is put onto the pedestal of our designed RF induction heating system. Then, the winding with alternating current induces scroll current on the surface of metallic electrodes due to skin effect. In this case, the current will generate Joule heat which could melt the surface metal of the electrodes. Finally, the CNTs will sink into the surface of the electrodes after short time heating. By varying the parameters of the RF source we can control the bonding process.

Description

    FIELD OF THE INVENTION
  • The invention relates generally to carbon structures. More particularly, the invention relates to carbon nanotubes bonding on metallic electrodes.
    • BACKGROUND OF THE INVENTION
  • The present invention relates to a large scale bonding technology of carbon nanotubes (CNTs) and metallic electrodes. And the invention can help realize wafer level CNTs devices fabrication.
  • The microelectronics industry's interest in the potential use of CNTs as building blocks of nano-scale devices is well founded due to their outstanding electronic, mechanical, and thermal properties. Extensive studies focused on the prototype devices such as field effect transistors and CNTs based sensors were designed and implemented with the objective of a future substitution of current components of digital electronic circuits. In addition, it has also been shown that carbon nanotubes can play a key role as an interconnection for nanoelectronic circuits. Hence, the contact bonding between metal and CNTs becomes an important issue in CNTs based nano-device fabrication.
  • However, many early nanotube devices just simply deposited CNTs on the top of metal electrodes without reliable bonding contact, which caused weak mechanical performance and high contact resistances between CNTs and electrodes. These disadvantages prevent further practical application of CNTs based device. To achieve better bonding contact between CNTs and metal electrodes, many methods had been utilized. For example, by exposing CNT contact area to a focused electron beam or ion beam, the contact resistance can be decreased by several orders of magnitude.
  • However, these methods are not easy to realize in real situation due to the limited access to a focused beam. In addition, the rapid thermal annealing method also was demonstrated to be able to reduce contact resistance. In this method, the entire substrate including CNTs, patterned metallic electrodes, and other device components underwent the high temperature process (600-800° C.). Such high temperature will severely limit the selection of materials that can be used on the substrate. Recently, an ultrasonic bonding technique has been developed for bonding single wall carbon nanotubes onto metal microelectrodes.
  • The bonding was formed by pressing CNTs against the electrodes with a vibrating press at an ultrasonic frequency. Although low resistance contacts between CNTs and metal electrodes can be obtained, the electrodes may be damaged during the bonding process. All these methods have a similar disadvantage from point of view of large scale CNTs devices fabrication for they just bond single device each time. Therefore, in order to realize wide application of CNTs devices, it is necessary to develop large scale bonding technology to satisfy reliable and reproducible large scale CNTs devices fabrication.
    • SUMMARY OF THE INVENTION
  • The present invention is to develop a large scale bonding technology of CNTs and metallic electrodes based on RF induction heating method which allows wafer level CNTs devices fabrication due to non-contact operation and local surface heating.
  • In one embodiment, a wafer with number of patterned electrodes is firstly deposited by CNTs via dielectrophoresis method. Then, the wafer is put on the pedestal of our designed induction heating system. The alternating magnetic field derived from the RF source power induces scroll current on the surface of metallic electrodes due to skin effect. In this case, the current will generate Joule heat which could melt the surface metallic electrodes within very short time, and the extent of melting depends on the power and frequency of our RF source and the heating time.
  • The shape of the coil and the type of the electrodes also affect the bonding process. Finally, the CNTs will sink into the surface of the electrodes after cooling in vacuum or pretection gas filled environment. As a result, the CNTs on all the electrodes of the wafer are bonded. The invention offers the possibility to realize the wafer level CNTs devices fabrication.
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • The accompanying drawings are included to provide a further understanding of embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and together with the description serve to explain principles of embodiments. Other embodiments and many of the intended advantages of embodiments will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.
  • FIG. 1 is a system for RF induction heating bonding of CNTs and electrodes.
  • FIG. 2A is a schematic representation of a wafer including patterned electrodes and CNTs placed in RF induction heating winding
  • FIG. 2B is a detail schematic representation of electrodes and CNTs patterned on substrate.
  • FIG. 3A shows an individual carbon nanotube bridges on two isolated electrodes before the RF induction heating bonding.
  • FIG. 3B shows an individual cabon nanotube sinks into the two isolated electrodes after the radioheating bonding process.
  • FIG. 4A is a scanning electron micrograph (SEM) of carbon nanotubes and electrodes after the RF induction heating bonding.
  • FIG. 4B is a SEM of the upsaid electrode in FIG. 4A and the bonded carbon nanotube.
  • FIG. 4C is a SEM of the blow electrode in FIG. 4A and the bonded carbon nanotubes.
    •  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.
  • First of all, the electrodes are fabricated by optical lithography and lift-off process. The shape and thickness of the electrodes can vary according to the design of the CNTs device.
  • Following the fabrication, the CNTs are deposited utilizing dielectrophoresis between pairs of electrodes. The frequency of alternating current in dielectrophoresis is 100 KHz-10 MHz, and the voltage is 1-5V, the time is ranged form 10 second to 30 second. The patterned electrodes and CNTs are shown in FIG. 2B.
  • FIG. 1 shows the RF induction heating bonding system of CNTs and electrodes. The system contains four parts: RF power 11 offers the power of the heating, water cooling system 12 is to cool the winding 13, and winding 13 is used to induce alternating magnetic field, the glass pedestal 14 supports the wafer during bonding process. The structure of winding can be varied according to electrodes patterns in order to obtain uniform heating.
  • In the operation, the RF current flow along the winding 13, and generates alternating electric-magnetic field. The glass pedestal 14 is put in the center of the winding 13. The wafer 15 with patterned metallic electrodes and CNTs are put onto the glass pedestal 14, as shown in FIG. 2A. After turning on the power, the alternating electric-magnetic fields generate whirling current on the surface of the metallic electrodes 16 and create heat to melt the surface metal of the electrodes 16. In order to avoid the whole electrodes are melted, the heating time should be not longer than 5 seconds. After natural cooling in vacuum or protection gas filled environment, the CNTs will sink into the electrodes, and the bonding process is finished.
  • The power of the RF source is ranged from 100 W to 500 W, and the frequency is ranged from 200 KHz to 15 MHz, all these parameters depends on the kinds, shape, size and thickness of the metallic electrodes.
  • FIG. 3A and FIG. 3B show the state before and after the RF induction heating bonging process. It is clear that the CNTs sink into the electrodes after the bonding, as shown in FIG. 3B.
  • FIG. 4A is a SEM image of CNTs after the RF induction heating bonding process. The two ends of the CNT sinks into the melting metallic electrode. It is indicated that the CNT is bonded into the electrodes. FIG. 4B shows the upsaid of the electrode shown in FIG. 4A after CNT sinks into it, and FIG. 4C shows the blow of the electrode shown in FIG. 4B after CNT sinks into it.
  • It is contemplated that features disclosed in this application, as well as those described in the above applications incorporated by reference, can be mixed and matched to suit particular circumstances. Various other modifications and changes will be apparent to those of ordinary skill.

Claims (16)

1. A method for large scale bonding carbon nanotubes on metallic electrodes, comprising: providing a wafer with number of patterned electrodes that is deposited by CNTs via dielectrophoresis method; putting the wafer onto the pedestal of the designed RF induction heating system; turning on the power and heating the wafer for a short time; cooling the wafer in vacuum or protection gas filled environment.
2. The method according to claim 1, wherein said a RF induction heating system including RF power, water cooling system, winding and glass pedestal.
3. The method according to claim 2, wherein said the structure of winding can be varied according to electrodes patterns.
4. The method according to claim 2, wherein said the water cooling system comprises a spiral pipe that coated outsaid of the winding, and the cooling is realized by flowing water through the pipe.
5. The method according to claim 1, wherein said RF induction heating process comprises tuning the parameters of frequency, power and heating time.
6. The method according to claim 5, wherein said the frequency of the RF source is ranged from 200 KHz to 15 MHz.
7. The method according to claim 5, wherein said the power of the RF source is ranged from 100 W to 500 W.
8. The method according to claim 5, wherein said the time of heating is not longer than 1 minute.
9. The method according to claim 1, wherein said the CNTs include individual carbon nanotubes, multi-wall carbon nanotubes and bundles of carbon nanotubes.
10. The method according to claim 1, wherein said the material of electrodes includes metals or alloy.
11. The method according to claim 10, wherein said the electrodes are fabricated by optical lithography and lift-off process.
12. The method according to claim 1, wherein said the CNTs are dispersed in aqueous solution.
13. The method according to claim 1, wherein said the CNTs are bridged between the pairs of electrodes by dielectrophoresis method.
14. The method according to claim 13, wherein said the frequency of alternating current in dielectrophoresis is 100 KHz-10 MHz.
15. The method according to claim 13, wherein said the voltage of dielectrophoresis is 1-5V.
16. The method according to claim 13, wherein said the time of the dielectrophoresis is ranged from 10 second to 30 second.
US12/109,936 2008-04-25 2008-04-25 Carbon nanotubes bonding on metallic electrodes Abandoned US20090314642A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US12/109,936 US20090314642A1 (en) 2008-04-25 2008-04-25 Carbon nanotubes bonding on metallic electrodes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US12/109,936 US20090314642A1 (en) 2008-04-25 2008-04-25 Carbon nanotubes bonding on metallic electrodes

Publications (1)

Publication Number Publication Date
US20090314642A1 true US20090314642A1 (en) 2009-12-24

Family

ID=41430119

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/109,936 Abandoned US20090314642A1 (en) 2008-04-25 2008-04-25 Carbon nanotubes bonding on metallic electrodes

Country Status (1)

Country Link
US (1) US20090314642A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102115029A (en) * 2009-12-31 2011-07-06 华中科技大学 Large-scale welding method for carbon nano tube devices
CN103278238A (en) * 2013-05-14 2013-09-04 西安交通大学 Ultraviolet light intensity sensor manufacturing method based on directional dielectrophoresis assembling structure
CN108666230A (en) * 2017-03-28 2018-10-16 至成精密工业股份有限公司 Levelling means for electronic product

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5558795A (en) * 1989-10-31 1996-09-24 International Business Machines Corporation Module encapsulation by induction heating
US20040241532A1 (en) * 2003-06-02 2004-12-02 Kim Young Nam Carbon nanotube or carbon nanofiber electrode comprising sulfur or metal nanoparticles as a binder and process for preparing the same
US7381316B1 (en) * 2002-04-30 2008-06-03 Northwestern University Methods and related systems for carbon nanotube deposition

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5558795A (en) * 1989-10-31 1996-09-24 International Business Machines Corporation Module encapsulation by induction heating
US7381316B1 (en) * 2002-04-30 2008-06-03 Northwestern University Methods and related systems for carbon nanotube deposition
US20040241532A1 (en) * 2003-06-02 2004-12-02 Kim Young Nam Carbon nanotube or carbon nanofiber electrode comprising sulfur or metal nanoparticles as a binder and process for preparing the same

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102115029A (en) * 2009-12-31 2011-07-06 华中科技大学 Large-scale welding method for carbon nano tube devices
CN103278238A (en) * 2013-05-14 2013-09-04 西安交通大学 Ultraviolet light intensity sensor manufacturing method based on directional dielectrophoresis assembling structure
CN108666230A (en) * 2017-03-28 2018-10-16 至成精密工业股份有限公司 Levelling means for electronic product

Similar Documents

Publication Publication Date Title
Chen et al. Ultrasonic nanowelding of carbon nanotubes to metal electrodes
Goodarzi et al. The effect of the cathode tip angle on the GTAW arc and weld pool: I. Mathematical model of the arc
US20110108806A1 (en) Method to Modify the Conductivity of Graphene
You et al. High‐resolution, parallel patterning of nanoparticles via an ion‐induced focusing mask
US20090314642A1 (en) Carbon nanotubes bonding on metallic electrodes
Tohmyoh A governing parameter for the melting phenomenon at nanocontacts by Joule heating and its application to joining together two thin metallic wires
Ranjan et al. Growing One‐Dimensional Metallic Nanowires by Dielectrophoresis
Tohmyoh et al. Manipulation and Joule heat welding of Ag nanowires prepared by atomic migration
Chen et al. Bonding of carbon nanotubes onto microelectrodes by localized induction heating
Xiong et al. Direct assembly of nanoparticles for large-scale fabrication of nanodevices and structures
Zhao et al. Decrease of contact resistance at the interface of carbon nanotube/electrode by nanowelding
CN105798447B (en) A kind of method and its application that metal nanometer line is prepared using nanometer interconnection
US8338296B2 (en) Method for forming a catalyst suitable for growth of carbon nanotubes
Aasmundtveit et al. Direct Integration of Carbon Nanotubes in CMOS, Towards an Industrially Feasible Process: A Review
Li et al. Direct Laser Writing of Multishaped VO2 Microactuators Based on Freestanding VO2 Film
Rajput et al. Ion‐beam‐assisted fabrication and manipulation of metallic nanowires
Zhang et al. Single electron transistor with programmable tunnelling structure
Hunter et al. Nanostructured material sensor processing using microfabrication techniques
Gaydamachenko et al. A Coulomb Blockade in a Nanostructure Based on Single Intramolecular Charge Center
Doelling et al. Nanospot welding and contact evolution during cycling of a model microswitch
Abe et al. Electric transport and mechanical strength measurements of carbon nanotubes in scanning electron microscope
WO2005038080A1 (en) Nozzle with nanosized heater, method for manufacturing same, and method for forming fine thin film
Shinya et al. Microscale structure fabrication using microprobe
Aasmundtveit Direct Integration of Carbon Nanotubes in Si Microsystems
Aldave et al. All‐Dry Deterministic Transfer of Thin Gold Nanowires for Electrical Connectivity

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION