CLIAMS:We claim:
1. A method for reusing a probe tip for a scanning probe microscope probe, the method comprising:
- selecting a probe tip specific to a desired function;
- establishing a hydrophilic interaction between the selected probe tip and the probe;
- replaceably attaching the selected probe tip to the probe for performing the desired function;
- detaching the probe tip subsequent to the performance; and
- repeating the above said steps at least once for the said probe tip at a later instant of time.
2. A method for reusing a probe tip for a scanning probe microscope probe, the method comprising:
- selecting a probe tip specific to a desired function;
- establishing a hydrophilic interaction between the selected probe tip and the probe;
- replaceably attaching the selected probe tip to the probe for performing the desired function;
- detaching the probe tip subsequent to the performance; and
- repeating the above said steps at least once for a probe tip distinct from the said probe tip at a later instant of time.
3. The method of claim 1, wherein the probe tip is selected from a plurality of probe tips.
4. The method of claim 3, wherein the plurality of probe tips is of identical geometry or of distinct geometry.
5. The method of claim 1, wherein the function is at least one of imaging, nanometrology, nanomanipulation, characterization of electrical properties, characterization of mechanical properties and characterization of chemical properties of a sample.
6. The method of claim 1, wherein the hydrophilic interaction is induced by a hydrophilic agent.
7. The method of claim 1, wherein the hydrophilic agent is selected from a group comprising of octane, decane, hexa-decane, mercury and liquid metals.
8. The method claim 1, wherein the hydrophilic agent is mounted on the probe for attachment to the probe tip.
9. An arrangement for reusing a probe tip for a scanning probe microscope, the arrangement comprising of:
a. A platform;
b. A sample holder mounted on the platform;
c. A first nano positioner formed for holding a plurality of probe tips;
d. An SPM probe mounted on a second nano positioner proximal to the sample holder on the platform, wherein the probe is configured for replaceably attaching a probe tip; and
e. An analyzer coupled to the SPM probe for sample measurement.
10. The arrangement of claim 9, wherein the platform is configured for enabling an in-plane translational motion.
11. The arrangement of claim 9, wherein the first nano positioner is provided with a cantilever support having plurality of slots for holding probe tip.
12. The arrangement of claim 9, wherein the SPM Probe is provided with a micro-channel, wherein the micro-channel delivers a predetermined volume of the hydrophilic agent to the probe.
13. The probe of claim 12, wherein the hydrophilic agent enables attachment of the probe tip to the probe.
14. The arrangement of claim 9, wherein the first nano positioner and the second nano positioner is configured for a three dimensional translational motion, a rotational motion or a combination thereof.
,TagSPECI:REUSABLE PROBE TIP FOR A SCANNING PROBE MICROSCOPE
FIELD OF INVENTION
The invention generally relates to the field of nanotechnology and particularly to a method for reusing a probe tip for a scanning probe microscope.
BACKGROUND
Scanning probe microscopy covers several techniques where a sharp tip is scanned over a surface for studying surface properties of materials. One common example of scanning probe microscopy is atomic force microscopy. Atomic force microscopy uses a probe and an atomically sharp tip rigidly attached at the end of the probe. A topographical image is obtained when the tip interacts with the surface of sample while scanning. Due to repeated use the tip gets worn thereby resulting in deterioration of the resolution of the atomic force microscope.
Conventionally, once the tip is worn, the entire probe needed to be replaced. Recently, there are methods available in the art for replacement or repair of the probe tip. The methods include but are not limited to clamping, wherein clamping is implemented by means of a vacuum pump, a mechanical clamp, an electrostatic clamp or an electromagnetic clamp, lateral focused ion beam milling, chemical vapor deposition, reconditioning of tips in situ via field induced diffusion. The drawbacks of the aforementioned techniques are requirement of special environment for tip replacement, no provision for re-use of the used tips and complex procedure for tip replacement.
BRIEF DESCRIPTION OF DRAWINGS
So that the manner in which the recited features of the invention can be understood in detail, some of the embodiments are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is a schematic representation of an arrangement for reuse of a probe tip, according to an embodiment of the invention.
FIG. 2 shows a micro-channel arrangement for delivery of the hydrophilic agent to the probe, according to an embodiment of the invention.
FIG. 3 shows attaching of the probe tip to the probe, according to an embodiment of the invention.
FIG. 4 shows the SPM scan of a standard sample, according to an embodiment of the invention.
FIG. 5 shows detaching of the probe tip from the probe, according to an embodiment of the invention.
SUMMARY OF THE INVENTION
One aspect of the invention provides a method for reusing a probe tip for a scanning probe microscope probe. The method includes, selecting a probe tip specific to a desired function, establishing a hydrophilic interaction between the selected probe tip and the probe, replaceably attaching the selected probe tip to the probe for performing the desired function, detaching the probe tip subsequent to the performance and repeating the above said steps at least once for the said probe tip at a later instant of time.
Another aspect of the invention provides a method for reusing a probe tip for a scanning probe microscope probe. The method includes, selecting a probe tip specific to a desired function, establishing a hydrophilic interaction between the selected probe tip and the probe, replaceably attaching the selected probe tip to the probe for performing the desired function, detaching the probe tip subsequent to the performance and repeating the above said steps at least once for a probe tip distinct from the said probe tip at a later instant of time.
Yet another aspect of the invention provides an arrangement for reusing a probe tip for a scanning probe microscope probe. The arrangement includes a platform, a sample holder mounted on the platform, a first nano positioner formed for holding a plurality of probe tips, an SPM probe mounted on a second nano positioner proximal to the sample holder on the platform, and an analyzer coupled to the SPM probe for sample measurement.
DETAILED DESCRIPTION OF THE INVENTION
Various embodiments of the invention provide a method for reusing a probe tip for a scanning probe microscope probe. The method includes, selecting a probe tip specific to a desired function, establishing a hydrophilic interaction between the selected probe tip and the probe, replaceably attaching the selected probe tip to the probe for performing the desired function, detaching the probe tip subsequent to the performance and repeating the above said steps at least once for the said probe tip at a later instant of time.
The method also includes, selecting a probe tip specific to a desired function, establishing a hydrophilic interaction between the selected probe tip and the probe, replaceably attaching the selected probe tip to the probe for performing the desired function, detaching the probe tip subsequent to the performance and repeating the above said steps at least once for a probe tip distinct from the said probe tip at a later instant of time.
The method for reusing of the probe tip is based on the principle of hydrophilic interaction between the hydrophilic agent mounted on the probe and the probe tip. To detach or remove the probe tip from the probe, the hydrophilic interaction is broken down. The detached probe tip is stored and reused for further scanning. The method described in brief herein above shall be described in detail.
A probe tip specific to perform a desired function is selected from a plurality of probe tips. In one example of the invention, the probe tips can be of identical geometry. In another example of the invention, each of the probe tips can be of distinct geometry. The selection of probe tip is dependent on the function; the probe tip needs to perform. The function of the probe tip includes but is not limited to imaging, nanometrology, nanomanipulation, characterization of electrical properties, characterization of mechanical properties and characterization of chemical properties of a sample.
After selecting the desired probe tip, the selected probe tip is replaceably attached to the probe for performing the desired function. The replaceable attachment is achieved by a hydrophilic interaction established between the probe and the probe tip. A hydrophilic agent including but not limited to octane, decane, hexa-decane, mercury and liquid metals, is delivered to the probe. Before mounting of the hydrophilic agent, the probe and probe tip are ensured to be hydrophilic.
FIG. 1 is a schematic representation of an arrangement for reuse of a probe tip, according to an embodiment of the invention. The arrangement includes a platform 1. The platform 1 is configured for enabling an in-plane translational motion. A sample holder 2 is mounted on the platform 1. A first nano positioner 3 is mounted on the platform 1 for holding a plurality of probe tips 4. The probe tips 4 are held on a cantilever support 5 having plurality of slots (not shown). In one embodiment of the invention, each of the probe tips 4 is releasably held on the slots on the cantilever support 5. The first nano positioner 3 is configured for movement on the platform 1. The example of movement includes but is not limited to a three dimensional translational motion, a rotational motion or a combination thereof. Further, the movement can be achieved by a mechanical means, an electrical means or a combination thereof.
An SPM probe 6 is mounted on a second nano positioner 7 proximal to the sample holder 2 on the platform 1. The second nano positioner 7 is configured for movement on the platform 1. The example of movement includes but is not limited to a three dimensional translational motion, a rotational motion or a combination thereof. Further, the movement can be achieved by a mechanical means, an electrical means or a combination thereof. The SPM probe 6 is configured for replaceably attaching a probe tip. A light source 8 is provided for directing a beam of light on the probe 6 and an analyzer 9 is coupled to the SPM probe 6 for sample measurement. In one embodiment of the invention, the SPM Probe 6 is provided with a micro-channel (not shown), wherein the micro-channel delivers a predetermined volume of the hydrophilic agent to the probe. Alternatively, a micro-pipette can be used for delivering the hydrophilic agent to the probe. The hydrophilic agent enables attachment of the probe tip 4 to the probe 6.
FIG. 2 shows a micro-channel arrangement for delivery of the hydrophilic agent to the probe, according to an embodiment of the invention. A micro-channel 10 is formed on the top surface 6a of the probe 6 mounted on the second nano positioner 7. The micro-channel 10 is then supplemented with a layer of PDMS 11. The PDMS layer 11 formed insulates the hydrophilic agent from the act of external influence. In one example of the invention, a desired volume of the hydrophilic agent is dispersed at a first end 10a of the micro-channel 10. The orientation of the micro-channel 10 enables uninterrupted flow of the hydrophilic agent to a second end 10 b wherein a droplet 12 is formed on the bottom surface 6b of the probe 6. Subsequent to the mounting of hydrophilic agent on the probe 6, the probe 6 is brought closer to the probe tip 4 for attaching. In an alternate embodiment of the invention, a micro-pipette can be used for mounting predetermined volume of the hydrophilic agent.
FIG. 3 shows attaching of the probe tip to the probe, according to an embodiment of the invention. The probe 6 with the droplet 12 containing the hydrophilic agent is brought closer to the probe tip 4. For attaching the probe tip 4 to the probe 6, initially, the probe 6 with the droplet 12 is aligned exactly above the probe tip 4. The alignment of the probe 6 to the probe tip 4 enables the hydrophilic agent contained in the droplet 12 to establish contact with the probe tip 4. The establishment of the contact results in adherence of the probe tip 4 to the droplet 12. The adherence is due to the adhesive forces resulting from the hydrophilic interaction between the hydrophilic agent and the top surface 4a of the probe tip 4. Subsequent to the attachment of the probe tip 4 to the probe 6, the probe 6 is lifted to dislodge the probe tip 4 from the slot 13 on the cantilever support 5.
Subsequent to the attaching of the probe tip 4 to the probe 6, scanning of desired sample is performed. FIG. 4 shows the SPM scan of a standard sample, according to an embodiment of the invention. Scanning of a standard sample (10 µm pitch square pits of 180 nm depth) is performed using the attached probe tip 4. The scan of the standard sample obtained by used probe tips is comparable in all specifications to the scan of the standard sample obtained by conventional SPM. The depths of the sample pits are observed to be around 180 nm which is comparable to the specification of the standard sample.
Subsequent to the performance the probe tip 4 is detached from the probe 6. FIG. 5 shows detaching of the probe tip from the probe, according to an embodiment of the invention. Initially, the probe 6 with the attached probe tip 4 is lodged inside the slot 13 of the cantilever support 5. The probe 6 is now moved in a horizontal direction with respect to the cantilever support 5. The horizontal movement causes disruption of the hydrophilic interaction, resulting in detaching of the probe tip 4 from the probe 6. The detached probe tip 4 can then be subsequently used by performing the method as described herein above.
The invention thus provides a method and an arrangement for reusing of probe tip for a scanning probe microscope probe which is easy to perform, simple, less time consuming and economical.
The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.