Method and device for measuring interfacial forces between nanowires

Abstract

The present invention discloses a method for measuring the interfacial force between nanowires, including measuring the deformation of two nanowires with overlapping heads when they move in opposite directions to produce a peeling trend and the change in the contact resistance between the two, thereby obtaining the relationship between the interfacial force and the contact resistance between the nanowires, and then measuring the contact resistance between the nanowires to obtain the interfacial force between the nanowires in real time. The present invention also discloses a device for measuring the interfacial force between nanowires. The present invention determines the relationship between the interfacial force and the contact resistance between the nanowires by deforming the nanowires, thereby indirectly realizing the real-time measurement of the interfacial force between the nanowires by measuring the contact resistance.

Description

Technical Field

[0001] The present invention relates to a nanomechanics measurement method and device, in particular to a method and device for measuring the interface force between nanowires. Background Art

[0002] Nanomechanics, as a branch of nanotechnology, focuses on the application of mechanical properties of engineering nanostructures and nanosystems. Nanomechanics not only dominates the mechanical properties of materials, but also has a significant impact on the magnetic, electrical, optical and other properties of materials. If the nanomechanical properties of materials can be regulated, it means that multiple properties of materials can be regulated at the same time. The existing method of measuring the forces between nanowires is to use nanowires as sensors, and use the displacement changes of nanowires when they are pulled out according to the cantilever beam principle to calculate the nanomechanical properties between nanowires. The above measurement method can only be performed in a stable state and cannot achieve continuous real-time measurement. Therefore, it is difficult to apply it to the study of the influence of liquids on interfacial forces. Summary of the invention

[0003] In view of the above-mentioned defects in the prior art, the task of the present invention is to provide a method for measuring the interface force between nanowires, so as to realize the real-time continuous measurement of the interface force between nanowires. Another task of the present invention is to provide a device for measuring the interface force between nanowires.

[0004] The technical solution of the present invention is as follows: A method for measuring the interfacial force between nanowires comprises the following steps:

[0005] Step 1, constructing a contact resistance measurement circuit between nanowires, wherein the contact resistance measurement circuit between nanowires comprises a first conductive substrate, a first nanowire, a second conductive substrate, and a second nanowire, wherein the tail of the first nanowire is fixed to the first conductive substrate and electrically connected, the tail of the second nanowire is fixed to the second conductive substrate and electrically connected, and the head of the first nanowire is parallelly overlapped with the head of the second nanowire to form a circuit path;

[0006] Step 2, causing the head of the first nanowire and the head of the second nanowire to have a peeling tendency in a direction perpendicular to the length direction of the second nanowire, determining the interface force between the first nanowire and the second nanowire according to the deformation amount of the head of the first nanowire or the second nanowire, and measuring the contact resistance between the nanowires under different deformation amounts;

[0007] Step 3, performing linear fitting based on the data of the interface force in step 2 and the contact resistance between the nanowires measured, determining the relationship parameters between the interface force between the nanowires and the contact resistance, and then obtaining the relationship between the interface force between the nanowires and the contact resistance;

[0008] Step 4: placing the nanowire-nanowire contact resistance measurement circuit constructed in step 1 under a variable environment of the influencing factors to be studied, and obtaining the nanowire-nanowire interface force based on the relationship between the nanowire-nanowire interface force and the contact resistance determined in step 3 according to the measured contact resistance between the first nanowire and the second nanowire.

[0009] Furthermore, the first conductive substrate is disposed on a fixed platform, and the second conductive substrate is disposed on a movable platform. In step 2, the stripping tendency is generated between the heads of the first nanowire and the second nanowire in a direction perpendicular to the length direction of the second nanowire by moving the movable platform so that the heads of the first nanowire and the second nanowire move in opposite directions to generate the stripping tendency.

[0010] Furthermore, portions of the first nanowire in contact with the first conductive substrate are fixedly connected, and portions of the second nanowire in contact with the second conductive substrate are fixedly connected.

[0011] Furthermore, the first nanowire and the first conductive substrate, as well as the second nanowire and the second conductive substrate are fixedly connected by using conductive glue.

[0012] Furthermore, in step 2, the interface force between the first nanowire and the second nanowire is determined by the deformation amount of the head of the first nanowire or the second nanowire according to the following formula:

[0013]

[0014] Wherein q is the interface force between the first nanowire and the second nanowire, δ is the deformation displacement of the first nanowire or the second nanowire head in a direction perpendicular to the length direction of the second nanowire, L1 is the length of the nanowire head extending out of the conductive substrate, L0 is the overlap length of the first nanowire and the second nanowire, E is the elastic modulus of the nanowire, and I is the moment of inertia.

[0015] Furthermore, the relationship between the interfacial force and the contact resistance between the nanowires in step 3 is expressed as R=KP -m , where R is the contact resistance, K is the material property and the performance coefficient of the material surface film, P is the interface force between the nanowires, and m is the film breakage related index. The relationship parameters between the interface force between the nanowires and the contact resistance in step 3 are K and m.

[0016] A device for measuring the interface force between nanowires, including a contact resistance measurement circuit between nanowires, a resistance measurement module and a force-to-electricity conversion module. The contact resistance measurement circuit between nanowires includes a first conductive substrate, a first nanowire, a second conductive substrate and a second nanowire. The tail of the first nanowire is fixed to the first conductive substrate and forms an electrical connection. The tail of the second nanowire is fixed to the second conductive substrate and forms an electrical connection. The head of the first nanowire and the head of the second nanowire are overlapped in parallel to form a circuit path. The resistance measurement module is used to measure the contact resistance between the first nanowire and the second nanowire and send it to the force-to-electricity conversion module. The force-to-electricity conversion module converts the measured contact resistance between the first nanowire and the second nanowire into the interface force between the nanowires according to a predetermined relationship between the interface force and the contact resistance between the nanowires.

[0017] The advantages of the present invention compared with the prior art are:

[0018] The method of the present invention causes the contact resistance change caused by the deformation of the first nanowire and the second nanowire due to the interaction force by moving, and then determines the linear change relationship between the contact resistance and the contact pressure between the nanowires. Then, the interface force between the two can be obtained by measuring the contact resistance of the first nanowire and the second nanowire. Since the resistance measurement technology is mature, reliable and has good real-time performance, the measurement of the interface force between nanowires is realized, which provides a guarantee for the study of the influence law of nanomechanical properties between nanowires. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the structure of the device for measuring the interface force between nanowires.

[0020] Figure 2 Schematic diagram of deformation of the first nanowire and the second nanowire. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the embodiments, but are not intended to limit the present invention.

[0022] Example, please combine Figure 1As shown, the contact resistance measurement circuit between nanowires involved in this embodiment includes a first conductive substrate 1, a first nanowire 2, a second conductive substrate 3 and a second nanowire 4. The first conductive substrate 1 and the second conductive substrate 3 are conductive glass, and of course they can also be ordinary glass with a conductive coating, or various conductive films with high conductivity. The first nanowire 2 and the second nanowire 4 are nanowires to be studied, which are AgNW nanowires in this embodiment. The tails of the AgNW nanowires are fixed to the surfaces of two conductive glasses with conductive glue to form an electrical connection. It should be pointed out that two AgNW nanowires of the same length are selected, and the length of the parts of the two AgNW nanowires in contact with the conductive glass surface is the same, and the parts in contact with the conductive glass are all fixedly connected and form a good electrical contact, which reduces the impact on the contact resistance between the nanowires.

[0023] In addition to the contact resistance measurement circuit between nanowires, the interface force measurement device between nanowires also includes a resistance measurement module 5 and a force-to-electric conversion module 6. A piece of conductive glass in the contact resistance measurement circuit between nanowires is fixed on a platform, and the other piece is fixed on a micro-displacement platform. The micro-displacement platform is moved so that the head of the first nanowire 2 and the head of the second nanowire 4 are parallelly overlapped to form a circuit path. The first conductive substrate 1 and the second conductive substrate 3 are respectively connected to the resistance measurement module 5, and the resistance measurement module 6 measures the contact resistance between the first nanowire 2 and the first nanowire 4 at this time. During the test, the micro-displacement platform will pull at a constant speed of 180nm / s in a direction perpendicular to the nanowire, so that the heads of the first nanowire 2 and the second nanowire 4 have a tendency to peel off in a direction perpendicular to the length direction of the second nanowire, and the interface force between the first nanowire 2 and the second nanowire 4 will cause the nanowire to deform. Please combine Figure 2 As shown, the relationship between the interface force per unit length q and the deformation δ is as follows

[0024]

[0025] Where q is the interfacial force between the first nanowire 2 and the second nanowire 4, δ is the deformation displacement of the head of the first nanowire 2 or the second nanowire 4 in a direction perpendicular to the length direction of the second nanowire 4, L1 is the length of the nanowire head extending out of the conductive substrate, L0 is the overlap length of the first nanowire 2 and the second nanowire 4, E is the elastic modulus of the nanowire, and I is the moment of inertia. Therefore, the interfacial force between the first nanowire 2 and the second nanowire 4 can be determined by the deformation of the head of the first nanowire 2. The micro-displacement platform is moved at different distances to produce different deformations of the first nanowire 2 and the second nanowire 4, and the contact resistance in the contact resistance measurement circuit between the nanowires under different deformations is measured at the same time, so that the relationship between the interfacial force and the contact resistance between the first nanowire 2 and the second nanowire 4 can be determined. The expression R=KP -mThe determined values ​​of K and m.

[0026] When studying the influence of changes in influencing factors on the interfacial force between nanowires, for example, studying the influence of liquid on the interfacial force between nanowires, the above-mentioned contact resistance measurement circuit between nanowires is placed in a test box filled with liquid vapor, and the liquid vapor concentration in the test box is continuously adjusted and controlled by a spray device to control the amount of liquid between the nanowires. Then, the resistance measurement module 5 measures the real-time contact resistance between the first nanowire 2 and the second nanowire 4 and sends it to the force-to-electricity conversion module 6. The force-to-electricity conversion module 6 can obtain the real-time interfacial force between the nanowires based on the determined interface force-to-electricity relationship.

Claims

1. A method for measuring the interfacial force between nanowires, comprising the following steps: Step 1, constructing a contact resistance measurement circuit between nanowires, wherein the contact resistance measurement circuit between nanowires comprises a first conductive substrate, a first nanowire, a second conductive substrate, and a second nanowire, wherein the tail of the first nanowire is fixed to the first conductive substrate and electrically connected, the tail of the second nanowire is fixed to the second conductive substrate and electrically connected, and the head of the first nanowire is parallelly overlapped with the head of the second nanowire to form a circuit path; Step 2, causing the head of the first nanowire and the head of the second nanowire to have a peeling tendency in a direction perpendicular to the length direction of the second nanowire, determining the interface force between the first nanowire and the second nanowire according to the deformation of the head of the first nanowire or the second nanowire according to the following formula, and measuring the contact resistance between the nanowires under different deformations; Wherein q is the interfacial force between the first nanowire and the second nanowire, δ is the deformation displacement of the head of the first nanowire or the second nanowire in a direction perpendicular to the length direction of the second nanowire, L1 is the length of the nanowire head extending out of the conductive substrate, L0 is the overlap length of the first nanowire and the second nanowire, E is the elastic modulus of the nanowire, and I is the moment of inertia; Step 3, performing linear fitting based on the data of the interface force in step 2 and the contact resistance between the nanowires measured, determining the relationship parameters between the interface force between the nanowires and the contact resistance, and then obtaining the relationship between the interface force between the nanowires and the contact resistance; The relationship between the interfacial force and contact resistance between nanowires is expressed as R=KP -m , wherein R is the contact resistance, K is the material property and the performance coefficient of the material surface film, P is the interfacial force between the nanowires, and m is the film breakage related index. The relationship parameters between the interfacial force between the nanowires and the contact resistance in step 3 are K and m; Step 4: placing the nanowire-nanowire contact resistance measurement circuit constructed in step 1 under a variable environment of the influencing factors to be studied, and obtaining the nanowire-nanowire interface force based on the relationship between the nanowire-nanowire interface force and the contact resistance determined in step 3 according to the measured contact resistance between the first nanowire and the second nanowire.

2. The method for measuring the interfacial force between nanowires according to claim 1, characterized in that: The first conductive substrate is disposed on a fixed platform, and the second conductive substrate is disposed on a movable platform. In step 2, the stripping tendency is generated between the heads of the first nanowire and the second nanowire in a direction perpendicular to the length direction of the second nanowire by moving the movable platform so that the heads of the first nanowire and the second nanowire move in opposite directions to generate the stripping tendency.

3. The method for measuring the interfacial force between nanowires according to claim 1, characterized in that: Portions of the first nanowire in contact with the first conductive substrate are fixedly connected, and portions of the second nanowire in contact with the second conductive substrate are fixedly connected.

4. The method for measuring the interfacial force between nanowires according to claim 1, characterized in that: The first nanowire and the first conductive substrate, as well as the second nanowire and the second conductive substrate, are fixedly connected by using conductive glue.

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