A novel single molecule scission technique measuring device with large angle open space

Abstract

The application discloses a novel single-molecule cleavage junction technology measuring device with a large-angle open space, a needle tip moving part is fixed on an optical platform through a displacement table, a transmission mechanism is arranged on the displacement table, a displacement sliding block is connected to the transmission mechanism, and a right-angle adapter structural member is fixedly installed on the front face of the displacement sliding block; a piezoelectric ceramic is arranged below the distal end of the right-angle adapter structural member, a shielding ring is sleeved with the piezoelectric ceramic, a needle cylinder is fixedly installed at the bottom of the piezoelectric ceramic, the needle cylinder is used for fixing a needle tip and leading out a needle tip signal, and a bottom disc is arranged below the front side of the displacement table. The application aims to make an architectural improvement on a cleavage junction technology based on a scanning tunneling microscope, so that the cleavage junction technology has an open space to accommodate the incidence and measurement of light and does not affect the stability of electrical measurement of the instrument itself, so that the instrument is fast in operation, convenient in sample preparation, and has the ability of optical regulation and spectroscopy measurement.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of measurement technology of single molecule electronics, and in particular to a novel single molecule break junction technology measurement device with a large angle open space. BACKGROUND

[0002] The measurement technology of molecular electronics has developed for decades, and a mature research system has been established for the testing of molecular electrical properties, including electrical conductivity, tunneling mechanism, etc. However, there is still a lack of effective research means for the coupling of molecules and electrodes, the connection configuration and direction, and the conformational changes of molecules between electrodes. The use of spectroscopy technology can effectively supplement these information, such as Raman spectroscopy which can detect the chemical bond vibration in the molecule, making it more convenient for researchers to understand the molecular conformation between electrodes.

[0003] The closest prior art implementation is:

[0004] There are some works that combine spectroscopy measurement with molecular electronics measurement instruments. These works are generally based on the instrument architecture of mechanical controllable break junction technology. The mechanical displacement part of this architecture is at the bottom of the sample, and the space above is kept open, so the space above can easily introduce the measurement components of the spectrum. However, the sample preparation process of mechanical controllable break junction technology is complicated, and the lead of the sample disc is easy to be damaged, limited by metal fatigue. The stability and repeated orientation performance of the substrate will also decay over time. At the same time, mechanical controllable break junction technology controls the distance between the electrodes through the elastic deformation of the metal substrate, and can only be fine-tuned in the z coordinate axis, so it cannot be used for optical imaging and can only be used for electrical measurement.

[0005] Another common molecular electronics measurement instrument is the break junction technology based on scanning tunneling microscopy. Compared with mechanical controllable break junction technology, the tip base configuration of scanning tunneling microscopy is derived from mature scanning tunneling microscopy, which has considerable advantages in sample preparation speed and sample stability. However, the sample of scanning tunneling microscopy is generally in a closed or semi-closed environment, and there is no open space above the sample, which is not conducive to the introduction of light and the arrangement of measurement devices.

[0006] In summary, the disadvantages of the prior art are:

[0007] Although the instrument architecture of mechanical controllable break junction technology is beneficial to light incidence and measurement, the sample preparation operation is complex and has a high failure rate. In the experimental process, due to the need to repeatedly push the metal substrate to deform and rebound thousands of times, it is easy to cause experimental stability to decline, liquid pool leakage and other problems due to metal fatigue. In addition, mechanical controllable break junction technology can only be accurately adjusted in the z direction, and there is no way to adjust the xy direction, so it only has the ability to perform electrical measurements in a very small range, and does not have the ability to image and switch the field of view.

[0008] Although the scanning tunneling microscope-based cleaving technology is more convenient and faster in sample preparation and experimental operation, the design of the sample disc and displacement device itself does not leave an open space, and the light has no space for incidence and measurement.

[0009] Therefore, there is an urgent need to design a new single-molecule cleaving technology measurement device with a large-angle open space to solve the above problems. SUMMARY

[0010] The purpose of the present application is to provide a new single-molecule cleaving technology measurement device with a large-angle open space to solve the above problems in the prior art.

[0011] In order to achieve the above purpose, the present application provides the following technical solutions:

[0012] A new single-molecule cleaving technology measurement device with a large-angle open space, comprising a displacement table, a transmission mechanism is arranged on the displacement table, and a displacement slider is connected to the transmission mechanism, and a right-angle adapter structure is fixedly installed on the front of the displacement slider;

[0013] A piezoelectric ceramic is arranged below the distal end of the right-angle adapter structure, a needle cylinder is fixedly installed at the bottom of the piezoelectric ceramic, a needle tip is arranged at the bottom of the needle cylinder, and a shielding ring is sleeved outside the piezoelectric ceramic;

[0014] A bottom disc is arranged below the front side of the displacement table, a 3Pin interface is arranged on one side of the top of the bottom disc, an installation groove is arranged on the outer wall of the top of the bottom disc, a gold sheet is arranged in the installation groove, a cover plate is fixedly arranged on the outer wall of the top of the bottom disc above the gold sheet, a shallow groove is arranged on the outer wall of the top of the cover plate, a Teflon liquid pool is inserted into the shallow groove, a plug-in groove is arranged on the outer wall of one side of the top of the bottom disc, a Teflon insulating wall is inserted into the plug-in groove, and a spring contact point is inserted into the Teflon insulating wall.

[0015] Further, the right-angle adapter structure is a right-angle triangular structure, and the needle tip and the displacement table form a staggered structure through the right-angle adapter structure.

[0016] Further, the 3Pin interface comprises a 3Pin interface plug and a 3Pin interface female seat, the 3Pin interface female seat is fixedly arranged on the outer wall of one side of the top of the bottom disc, the 3Pin interface plug is inserted into the 3Pin interface female seat, a plurality of contact heads are arranged in the 3Pin interface female seat, and a fixed buckle is arranged on the top of the 3Pin interface plug.

[0017] Further, the Teflon liquid pool is made of Teflon material, has good acid and alkali resistance, and has good heat resistance.

[0018] Further, the base of the gold sheet is obtained by plating a gold 111 layer on a 3cm*3cm mica sheet.

[0019] Further, the base plate fixes the sample area on the optical platform, and the base plate is used at least to assist in fixing and supporting the gold sheet and the base.

[0020] Further, the outer wall on one side of the top of the base plate is provided with a terminal post, and the terminal post is electrically connected with a 3Pin interface; one side of the spring contact point is fixedly connected with a signal line, and the distal end of the signal line is fixedly provided with a connecting ring mounted on the terminal post.

[0021] In the above technical solution, the present application provides a novel single-molecule break junction technology measuring device with a large-angle open space. The purpose of the present application is to make structural improvements to the break junction technology based on a scanning tunneling microscope, so that it has an open space to accommodate the incidence and measurement of light, and does not affect the stability of the electrical measurement of the instrument itself, so that the instrument is fast in operation, convenient in sample preparation, and has the ability to perform spectroscopy measurement; compared with the traditional instrument architecture, the present application provides a more open space to accommodate the optical path, thereby facilitating the combination of molecular electronics measurement and spectroscopy measurement. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments or prior art of the present application, the drawings needed in the embodiments will be briefly introduced as follows. The drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0023] Figure 1 The displacement table structure schematic diagram provided for the embodiment of the novel single-molecule break junction technology measuring device with a large-angle open space.

[0024] Figure 2 The mounting spectroscopy measurement lens and base plate structure schematic diagram provided for the embodiment of the novel single-molecule break junction technology measuring device with a large-angle open space.

[0025] Figure 3 The displacement slider, right-angle adapter structure and base plate structure top view provided for the embodiment of the novel single-molecule break junction technology measuring device with a large-angle open space.

[0026] Figure 4 The structure schematic diagram on the base plate provided for the embodiment of the novel single-molecule break junction technology measuring device with a large-angle open space.

[0027] Figure 5An exploded diagram of the structure on the chassis provided for an embodiment of a novel single-molecule cleavage technique measurement device with a large-angle open space according to the present invention.

[0028] Description of reference numerals:

[0029] 1. Translation stage; 2. Motor mount; 3. Support plate; 4. Bearing seat; 5. Screw; 6. Stepper motor; 7. Screw nut; 8. Displacement slider; 9. Right-angle adapter structure; 10. Piezoelectric ceramic; 11. Shielding ring; 12. Syringe; 13. Needle tip; 14. Spectroscopy measurement lens for analog setup; 15. Chassis; 16. 3-pin interface plug-in block; 17. 3-pin interface female socket; 18. Contact head; 19. Fixing buckle; 20. Terminal; 21. Mounting slot; 22. Gold sheet; 23. Cover plate; 24. Shallow groove; 25. Teflon liquid pool; 26. Connecting ring; 27. Signal line; 28. Spring contact point; 29. ​​Teflon insulation wall. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] like Figures 1-5 As shown, an embodiment of the present invention provides a novel single molecule fission technology measurement device with a large-angle open space, comprising a displacement stage 1, a transmission mechanism provided on the displacement stage 1, and a displacement slider 8 connected to the transmission mechanism, a right-angle transition structure 9 fixedly mounted on the front of the displacement slider 8; a piezoelectric ceramic 10 is provided below the distal end of the right-angle transition structure 9, and a syringe 12 is fixedly mounted on the bottom of the piezoelectric ceramic 10, a needle tip 13 is provided at the bottom of the syringe 12, and a shielding ring 11 is sleeved on the outside of the piezoelectric ceramic 10; a shielding ring 11 is provided on the front side and below the displacement stage 1. There is a chassis 15, and a 3Pin interface is provided on one side of the top of the chassis 15. A mounting groove 21 is provided on the outer wall of the top of the chassis 15, and a gold sheet 22 is provided inside the mounting groove 21. A cover plate 23 fixed to the outer wall of the top of the chassis 15 is provided above the gold sheet 22. A shallow groove 24 is provided on the outer wall of the top of the cover plate 23, and a Teflon liquid pool 25 is inserted into the shallow groove 24. A slot is provided on the outer wall of one side of the top of the chassis 15, and a Teflon insulating wall 29 is inserted into the slot, and a spring contact point 28 is inserted into the Teflon insulating wall 29.

[0032] In this embodiment, a translation stage 1 is provided with a transmission mechanism. By starting a stepping motor 6, a displacement slider 8 can be driven to move up and down with micron-level precision, thereby driving the needle tip 13 to move up and down.

[0033] In this embodiment, a displacement slider 8 is connected to the transmission mechanism, and a right-angle transition structure 9 is fixedly installed on the front of the displacement slider 8;

[0034] Specifically, the front section of the right-angle adapter structure 9 is an isosceles triangle structure, which has stability and opens more space as much as possible. The needle tip 13 and the displacement table 1 form a staggered structure through the right-angle adapter structure 9, which provides a sufficient open space in the sample area, facilitating the combination with spectroscopy research.

[0035] In this embodiment, a piezoelectric ceramic 10 is arranged below the distal end of the right-angle adapter structure 9. The piezoelectric ceramic 10 has high precision and repeatable positioning, and performs well in molecular electronics measurement experiments. The piezoelectric ceramic 10 is used to provide accurate control of the z-axis in single-molecule electronics, and the control accuracy can reach picometer level, while the maximum stroke is in micrometer level. Therefore, the piezoelectric ceramic 10 can work in cooperation with the stepper motor 6 and the displacement slider 8. The bottom of the piezoelectric ceramic 10 is fixedly installed with a needle cylinder 12. The bottom of the needle cylinder 12 is provided with a needle tip 13. The needle cylinder 12 plays a role of fixing the needle tip 13 and guiding the signal of the needle tip 13 out through a coaxial line. The piezoelectric ceramic 10 is sleeved with a shielding ring 11. The piezoelectric ceramic 10 needs to input an external voltage signal. The noise of the input signal, start and stop, and the leakage of the piezoelectric ceramic 10 itself will directly affect the connected needle tip 13. Therefore, a copper shielding ring 11 is added at the connection between the needle tip 13 and the piezoelectric ceramic 10 to shield the noise of the mechanical movement part. The shielding ring 11 is grounded through a cable.

[0036] In this embodiment, a bottom disc 15 is arranged below the front side of the displacement table 1.

[0037] Specifically, the bottom disc 15 fixes the sample area on the optical platform, and the bottom disc 15 is used to fix and support the gold sheet 22 substrate.

[0038] In this embodiment, a 3Pin interface is arranged on one side of the top of the bottom disc 15. The 3Pin interface integrates the signal line of the spring contact point 28 and the reference electrode and counter electrode signal line required by electrochemistry into one terminal, facilitating the installation of the sample disc.

[0039] Specifically, the 3Pin interface includes a 3Pin interface plug block 16 and a 3Pin interface female seat 17. The 3Pin interface female seat 17 is fixed on the outer wall on one side of the top of the bottom disc 15. The 3Pin interface plug block 16 is plugged into the inside of the 3Pin interface female seat 17. The inside of the 3Pin interface female seat 17 is provided with a plurality of contact heads 18. The top of the 3Pin interface plug block 16 is provided with a fixing buckle 19.

[0040] Specifically, a wiring column 20 is arranged on the outer wall on one side of the top of the bottom disc 15, and the wiring column 20 is electrically connected with the 3Pin interface. One side of the spring contact point 28 is fixedly connected with a signal line 27, and the distal end of the signal line 27 is fixedly provided with a connecting ring 26 which is installed on the wiring column 20.

[0041] In this embodiment, the outer wall of the top of the chassis 15 is provided with a mounting groove 21, and the inside of the mounting groove 21 is provided with a gold sheet 22, and the gold sheet 22 is provided with a cover plate 23 fixed on the outer wall of the top of the chassis 15, and the cover plate 23 is used to press down the Teflon liquid pool 25 and the gold sheet 22, and fix the sample;

[0042] Specifically, the base of the gold sheet 22 is obtained by plating a gold 111 layer on a 3cm*3cm mica sheet, and the gold sheet 22 is used as an electrode for applying a bias voltage in the experiment, and also needs to bear the sample.

[0043] In this embodiment, the outer wall of the top of the cover plate 23 is provided with a shallow groove 24, and the inside of the shallow groove 24 is inserted with a Teflon liquid pool 25;

[0044] Specifically, the Teflon liquid pool 25 is made of Teflon material, which has good acid and alkali resistance, heat resistance, and sufficient toughness, and is used to fix the gold sheet 22 and contain the solution to be measured.

[0045] In this embodiment, the outer wall of the top of the chassis 15 is provided with a plug-in groove, and the inside of the plug-in groove is inserted with a Teflon insulating wall 29, and the Teflon insulating wall 29 is used to fill the gap between the plug-in groove on the cover plate 23 and the spring contact point 28 by using the toughness of the Teflon material, so as to firmly fix the spring contact point 28, and also prevent the cover plate 23 and the spring contact point 28 from directly contacting, thereby avoiding the bias voltage signal grounding, and the inside of the Teflon insulating wall 29 is inserted with a spring contact point 28, one end of the spring contact point 28 contacts the gold sheet 22, and is used to input the bias voltage signal, and the spring contact point 28 relies on slight elasticity to ensure good contact with the gold sheet 22.

[0046] In this embodiment, a spectroscopy measurement lens 14 is simulated on the top of the chassis 15, and the opening angle between the chassis 15 and the right-angle adapter structure 9 is measured to be at least φ＞ 80 degrees and θ＞145度 light introduction / extraction angle at the needle tip.

[0047] Working principle:

[0048] Sample assembly process: First, anneal the gold sheet 22 and place it in the mounting slot 21 provided in the chassis 15. Secure the Teflon liquid reservoir 25 to the cover 23 and then press it onto the gold sheet 22. Secure the cover 23 to the chassis 15 with M3 screws at both ends, ensuring the Teflon liquid reservoir 25 is leak-proof. Then, add the liquid sample. Next, insert the spring contact 28 into the Teflon insulating wall 29 and then into the slot provided in the cover 23. Ensure good contact between the spring contact 28 and the gold sheet 22. Connect the terminal of the spring contact 28 to the terminal 20 via the signal cable 27 and the connecting ring 26. The terminal 20 is then connected to the 3-pin connector via the signal cable. The 3-pin connector is then connected to the controller. The chassis 15 can then be secured to the optical platform using M6 screws and copper standoffs.

[0049] Needle tip assembly process: Insert the prepared needle tip 13 into the syringe 12 and fix it, then connect the syringe 12 part to the bottom end of the piezoelectric ceramic 10, and put the shielding ring 11 on the outside of the piezoelectric ceramic 10. The connecting wire of the needle tip 13 is connected to the current amplifier to detect the tunnel current signal of the needle tip 13.

[0050] After the sample and needle tip 13 are assembled, the automated program uses the needle tip tunneling current as a basis for judgment. By moving the stepper motor 6 on the translation stage 1, the stepper motor 6 can rotate the lead screw 5, which in turn drives the lead screw nut 7 and the displacement slider 8 to coarsely adjust the distance between the needle tip 13 and the gold sheet 22. The piezoelectric ceramic 10 then fine-tunes this distance, moving the needle tip 13 closer to and further away from the chassis 15. This process is repeated thousands of times, while the tunneling current information from the needle tip 13 to the chassis 15 is recorded for subsequent analysis. When a molecular signal is captured, the light from the spectroscopy measurement lens 14 is focused on the needle tip 13 area to capture the molecule's spectroscopic signal.

[0051] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A novel single-molecule cleavage technique measuring device with a large-angle open space, comprising a displacement stage (1), characterized in that: The displacement platform (1) is provided with a transmission mechanism, and a displacement slider (8) is connected to the transmission mechanism, and a right-angle transition structure (9) is fixedly mounted on the front of the displacement slider (8); A piezoelectric ceramic (10) is provided below the distal end of the right-angle transition structural member (9), and a syringe (12) is fixedly mounted on the bottom of the piezoelectric ceramic (10), a needle tip (13) is provided on the bottom of the syringe (12), and a shielding ring (11) is sleeved on the outside of the piezoelectric ceramic (10); A chassis (15) is provided at the lower front side of the displacement stage (1), a 3-pin interface is provided on one side of the top of the chassis (15), a mounting groove (21) is provided on the outer wall of the top of the chassis (15), a gold sheet (22) is installed in the mounting groove (21), a cover plate (23) fixed on the outer wall of the top of the chassis (15) is provided above the gold sheet (22), a shallow groove (24) is provided on the outer wall of the top of the cover plate (23), and a Teflon liquid pool (25) is fixed in the shallow groove (24), a slot is provided on the outer wall of one side of the top of the chassis (15), a Teflon insulating wall (29) is inserted into the slot, and a spring contact point (28) is inserted into the Teflon insulating wall (29); The upper side of the chassis (15) has an open space structure, a spectral measurement lens (14) is provided, and a light introduction / extraction angle of at least φ>80 degrees and θ>145 degrees is provided at the needle tip. A terminal (20) is provided on the outer wall of the top side of the chassis (15), and the terminal (20) is electrically connected to the 3Pin interface. A signal line (27) is fixedly connected to one side of the spring contact point (28), and a connecting ring (26) installed on the terminal (20) is fixedly provided at the far end of the signal line (27).

2. A novel single molecule cleavage technique measurement device with a large-angle open space according to claim 1, characterized in that: The right-angle transition structural member (9) is a right-angled triangle structure, and the needle tip (13) and the displacement platform (1) form a dislocation structure through the right-angle transition structural member (9).

3. The novel single molecule cleavage technique measurement device with a large angle open space according to claim 1, characterized in that: The 3Pin interface comprises a 3Pin interface plug-in block (16) and a 3Pin interface female seat (17), wherein the 3Pin interface female seat (17) is fixed on the outer wall of one side of the top of the chassis (15), and the 3Pin interface plug-in block (16) is plugged into the interior of the 3Pin interface female seat (17), wherein a plurality of contact heads (18) are provided inside the 3Pin interface female seat (17), and a fixing buckle (19) is provided on the top of the 3Pin interface plug-in block (16).

4. The novel single molecule cleavage technique measurement device with a large angle open space according to claim 1, characterized in that: The Teflon liquid pool (25) is made of Teflon material and has good acid and alkali resistance and heat resistance.

5. The novel single molecule cleavage technique measurement device with a large-angle open space according to claim 1, characterized in that: The base of the gold sheet (22) is obtained by plating 111 layers of gold on a 3 cm*3 cm mica sheet.

6. The novel single molecule cleavage technique measurement device with a large angle open space according to claim 5, characterized in that: The chassis (15) fixes the sample area on the optical platform, and the chassis (15) is used to assist in fixing and supporting the gold sheet (22) substrate.

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