CN112058326A - A device for assisted femtosecond laser micro-nano fabrication to realize long-distance high-speed droplet transport - Google Patents

Abstract

A device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed droplet transportation, comprising a horizontal stage, the bottom of the horizontal stage is connected with a shock-proof base, and the top of the horizontal stage is connected with an electric printing feed side plate , a rib plate is connected between the electric printing feeding side plate and the horizontal stage, and the electric printing feeding side plate is provided with a trapezoidal slideway arranged at equal intervals and a high-precision scale plate on one side; the trapezoidal slideway is provided with There is a micro-injector carrying platform; the micro-injector is fixed on the micro-injector carrying platform; just below the micro-injector is a rotatable flexible hydraulic clamp fixed on a horizontal stage; the invention can effectively assist the femtosecond Laser micro-nano processing technology can control the surface wettability of materials, and prepare stable and reconfigurable "dual gradient" wettable surfaces with high efficiency and high quality, which can realize long-distance high-speed droplet transport.

Description

A device for assisted femtosecond laser micro-nano fabrication to realize long-distance high-speed droplet transport

technical field

The invention relates to the technical field of material surface wettability regulation, in particular to a device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed droplet transportation.

Background technique

With the research on extremely wettable surfaces such as superhydrophobicity, various extremely wettable surfaces have been applied to droplet manipulation, such as non-destructive droplet transfer, droplet transport, etc., where droplet transport is generally the effect of gradient wettability surfaces It can realize the spontaneous and directional movement of droplets without the assistance of external forces, and has great application value in the fields of cell engineering, anti-microbial corrosion, microfluidics and condensation heat transfer.

Generally, self-driven gradient wettability surfaces are mainly achieved by constructing surface chemical composition gradients or constructing surface microstructure gradients, such as chemical modification of different concentration gradients and construction of gradient microstructures based on femtosecond laser micro-nano fabrication. On the one hand, these traditional methods have shortcomings and deficiencies such as complex process, low efficiency, poor durability and stability, and low recycling rate. It is achieved by overcoming the resistance of droplet movement in a specific direction. Although it has the advantage of controlling droplet transport distance and droplet transport speed to a certain extent, it is limited to long-distance low-speed droplet transport or short-distance high-speed droplet transport. Transport, that is, high-speed droplet transport requires a larger wetting gradient, which in turn limits the distance that droplets can be transported, and correspondingly, a long transport distance requires a small wetting gradient, which limits its transport speed, Long-distance transport and high-speed transport have become a pair of contradictions; in addition, the gradient wettability surface based on the control of microscopic morphology or chemical composition cannot be simply reconstructed by the droplet transport path, which limits its application prospects to a certain extent. The scope of application, while limiting its transition to practical applications.

SUMMARY OF THE INVENTION

In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed droplet transportation, which can effectively assist femtosecond laser micro-nano processing technology to control the surface wettability of materials, Efficient and high-quality preparation of stable and reconfigurable gradient wettability surfaces while enabling high-speed droplet transport over long distances.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed droplet transportation, comprising a horizontal stage 2, the bottom of the horizontal stage 2 is connected with an anti-vibration base 1, and the top of the horizontal stage 2 is connected with an electroprinter The feeding side plate 4, the rib plate 3 is connected between the electric printing feeding side plate 4 and the horizontal stage 2, and the electric printing feeding side plate 4 is provided with trapezoidal slides 6 arranged at equal intervals and on the side close to the side. The high-precision scale plate 8 of the The rotatable flexible hydraulic clamp 5 on the stage 2.

The axial direction of the rotatable flexible hydraulic clamp 5 is arranged in parallel with the electric printing feed side plate 4, and the whole is mounted on the clamp base 10. The clamp base 10 is provided with symmetrically distributed along the central plane of the clamp base 10. The horizontal feed rail 11 is provided with a horizontal feed platform 12; the right end of the horizontal feed platform 12 is connected to the output end of the micro differential 21, and the output end of the micro differential 21 is connected to the horizontal feed connecting rod 22 is connected at one end; the other end of the horizontal feed connecting rod 22 is connected with an adjustable micro horizontal feed device 23;

The horizontal feeding platform 12 is connected with a clamp extension table 13, the clamp extension table 13 is of a left-right symmetrical structure, and the left and right sides thereof are connected with an adjustable micro-feeding device fixing frame 14; the adjustable micro-feeding device fixing frame 14 An adjustable micro-feeding device 15 is connected to the outer side, and a locking device 16 is fixed inside; the other end of the locking device 16 is connected to the hydraulic feeding device 18; the output shaft of the hydraulic feeding device 18 is connected to the flexible fixture head 17;

The two ends of the adjustable micro-feeding device 15 are provided with an inner knob 19 of the adjustable micro-feeding device and an outer knob 20 of the adjustable micro-feeding device. The inner knob 19 of the adjustable micro-feeding device drives the hydraulic feeding device by driving. 18. The flexible clamp head 17 realizes the action of clamping the sample, and the outer knob 20 of the adjustable micro-feeding device is used to adjust different angular orientations of the flexible clamp head 17.

The shock-proof base 1 is made of industrial high-grade rubber material.

The rib 3 is symmetrically arranged with the center plane of the horizontal stage 2 as the central axis, and a rounded corner with a radius of 10 mm is set at the junction of the rib 3 and the electro-printing feeding side plate 4 .

The micro-injector 7 is a liquid-phase micro-injection device with a measuring range of 100 μL, the axis of which is parallel to the trapezoidal slide 6 .

The high-precision scale plate 8 is a measuring tool with a measuring range of 200 mm and an accuracy of micrometers, and its readings directly correspond to the values of droplets of different heights, which can be converted into corresponding Weber numbers.

The micro-differential gear 21 is a micro-precision transmission for regulating the feeding speed of the horizontal feeding platform 12 .

The adjustable micro-feeding device 15 , the locking device 16 , the flexible clamp head 17 , and the hydraulic feeding device 18 are symmetrically arranged on the left and right sides of the clamp extension table 13 with the central plane as the central axis.

The rotatable flexible hydraulic clamp 5 can realize rotation within the range of -90° to 90° and movement in the direction perpendicular to the trapezoidal slideway 6 .

A droplet transport process using a device for assisted femtosecond laser micro-nano fabrication to achieve long-distance high-speed droplet transport, including the following steps:

1) Prepare gradient periodic microstructures on sample substrates by femtosecond laser using arc scanning mode with changing scanning spacing;

Ⅱ) Preparation of the first heavily gradient wettability surface by chemical vapor deposition of _SiO2 nanoparticles and low surface energy species PFOTS on the gradient periodic microstructure;

III) On the first heavily gradient wettability surface, a second “gradient” surface, i.e., a charge density gradient surface, was prepared by a device assisted by femtosecond laser micro-nano fabrication for long-distance high-speed droplet transport, thereby obtaining a double-layered “gradient” surface. Gradient wettability surface monomers;

Ⅵ) On a large-area sample substrate, by adjusting the array spacing of the surface monomers with double gradient wettability, and repeating steps I)-step III) to realize the preparation of long-distance high-speed droplet transport surface, the droplets have double gradient wettability on the surface. Due to the need for high-speed transport on the surface due to the dual effects of wettability gradient and charge density gradient, the alternate array arrangement of the double-gradient wettability surface and the untreated area realizes long-distance transport, and finally achieves long-distance high-speed droplet transport. need.

Compared with the prior art, the beneficial effects of the present invention are:

The device of the present invention can prepare a "dual gradient" surface, and the first heavy gradient wettability surface is directly endowed with wettability through the process of femtosecond laser micro-nano fabrication combined with low surface energy chemical modification using an arc scanning method with changing scanning spacing. Gradient; the second "gradient" surface is given based on the charge density gradient realized by the device of the present invention, and the charge density gradient surface is formed by impacting the sample substrate with water droplets with different Weber numbers. The charge density gradient surface formed by the sample substrate with a heavy gradient wettability surface improves the self-driving speed during droplet transport. The precise control of the density gradient, thereby realizing the precise control of the self-driving speed of the droplet.

Since the charge density gradient surface only forms a charge density area in the area above the diagonal in a certain thickness area, and the lower part is still electrically neutral, therefore, the charge density gradient surface can be treated by contact aging treatment with materials such as metals with high conductivity , so as to realize the reconstruction of the charge density gradient surface, which can realize the reconstruction of different transport paths, transport speeds and transport distances.

By repeatedly fabricating periodic arrays with dual gradient features on a large-area substrate with appropriate spacing, the realization of high-speed droplet transport over long-distance specific paths can be accomplished. The invention simultaneously realizes long-distance and high-speed transportation of droplets, and has the advantages of path selectivity and reconfigurability.

Description of drawings

Figure 1 is a side view of the present invention.

FIG. 2 is a three-dimensional schematic diagram of the present invention.

FIG. 3 is a three-dimensional schematic diagram of the rotatable flexible hydraulic clamp of the present invention.

4 is a schematic diagram of a long-distance high-speed droplet transport process using the device of the present invention.

Detailed ways

The technical solutions of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figures 1 and 2, a device for assisted femtosecond laser micro-nano manufacturing to realize long-distance high-speed droplet transportation includes a horizontal stage 2, and the bottom of the horizontal stage 2 is evenly distributed by means of screw connections. 4 anti-vibration bases 1, the anti-vibration base 1 is made of industrial high-grade rubber material, which can effectively reduce or even prevent experimental errors caused by vibration; the top of the horizontal stage 2 is connected with an electric printing feed side plate 4 by welding , a rib 3 is connected between the electric printing feed side plate 4 and the horizontal stage 2, and the rib 3 is symmetrically arranged with the central plane of the horizontal stage 2 as the central axis. The junction of the feeding side plate 4 is provided with a rounded corner with a radius of 10mm to reduce or even prevent the occurrence of stress concentration, so as to improve the structural strength and stability; The slideway 6 and the position close to the left side are the high-precision scale plates 8 prepared by laser etching; the trapezoidal slideway 6 is provided with a micro-sampler carrying platform 9 in an embedded manner; the micro-sampler carrying platform 9 passes through A micro-injector 7 is fixed by magnetic adsorption; the micro-injector 7 is a liquid-phase micro-injection device with a measuring range of 100 μL, and its axis direction is parallel to the trapezoidal slide 6; the high-precision scale plate 8 is a measuring tool with a measuring range of 200mm and an accuracy of micrometers. Its readings directly correspond to the values of droplets of different heights, which can be converted into the corresponding Weber numbers; the micro-injector 7 is directly under the horizontal load through bolts. Rotatable flexible hydraulic clamp 5 on table 2.

As shown in FIG. 3 , the axial direction of the rotatable flexible hydraulic clamp 5 is arranged in parallel with the electro-printing feed side plate 4 , and the whole is mounted on the clamp base 10 . The horizontal feed guide rail 11 is symmetrically distributed on the central surface; the horizontal feed guide rail 11 is provided with a horizontal feed platform 12 in an inline manner; the right end face of the horizontal feed platform 12 is connected to the output end of the micro differential 21 through threads; The micro differential 21 is a micro high-precision transmission, which can regulate the feed speed of the horizontal feed platform 12. The output end of the micro differential 21 is connected to one end of the horizontal feed connecting rod 22 through a universal joint; The other end of the connecting rod 22 is connected with an adjustable micro-level horizontal feeding device 23 through threads; the horizontal feeding platform 12 is connected with a clamp extension table 13 by bolts; the clamp extension table 13 has a left-right symmetrical structure. An adjustable micro-feeding device fixing frame 14 is connected to the side by threads; the outer side of the adjustable micro-feeding device fixing frame 14 is threadedly connected with an adjustable micro-feeding device 15, and the inner side is also threadedly fixed with a locking device 16; the other end of the locking device 16 is connected with the hydraulic feeding device 18; the output shaft of the hydraulic feeding device 18 is connected with the flexible fixture head 17 by means of screw connection; the adjustable micro-feeding device 15, the locking device 16 , The flexible clamp head 17 and the hydraulic feed device 18 are symmetrically arranged on the left and right sides with the central plane of the clamp extension table 13 as the central axis; the two ends of the adjustable micro feed device 15 are provided with adjustable micro feed The inner knob 19 of the device and the outer knob 20 of the adjustable micro-feeding device. The inner knob 19 of the adjustable micro-feeding device drives the hydraulic feeding device 18 to make the flexible clamp head 17 realize the action of clamping the sample. The knob 20 is used to adjust different angular orientations of the flexible clamp head 17 .

As shown in 4, the droplet transport process using a device for assisted femtosecond laser micro-nano fabrication to realize long-distance high-speed droplet transport includes the following steps:

1) Prepare gradient periodic microstructures on sample substrates (such as silicon, etc.) by femtosecond laser using arc scanning with changing scanning spacing;

Ⅱ) Preparation of the first heavily gradient wettability surface by chemical vapor deposition of _SiO2 nanoparticles and low surface energy species PFOTS on the gradient periodic microstructure;

III) On the first heavily gradient wettability surface, a second “gradient” surface, i.e., a charge density gradient surface, was prepared by a device assisted by femtosecond laser micro-nano fabrication for long-distance high-speed droplet transport, thereby obtaining a double-layered “gradient” surface. Gradient wettability surface monomers;

Ⅵ) On a large-area sample substrate, by adjusting the array spacing of the surface monomers with double gradient wettability, and repeating steps I)-step III) to realize the preparation of long-distance high-speed droplet transport surface, the droplets have double gradient wettability on the surface. Due to the need for high-speed transport on the surface due to the dual effects of wettability gradient and charge density gradient, the alternate array arrangement of the double-gradient wettability surface and the untreated area realizes long-distance transport, and finally achieves long-distance high-speed droplet transport. need.

The working principle of the device of the present invention is:

Firstly, femtosecond laser was used to combine _SiO2 nanoparticles and PFOTS low surface energy chemical modification in arc scanning mode with different scanning distances to obtain the surface of the sample substrate with the first gradient wettability. At the same time, acetone, absolute ethanol, deionized water were used Ultrasonic bath combined with nitrogen drying for 10min each to clean the sample surface impurities; then, the cleaned sample substrate with the first heavy gradient wettability surface was placed on the flexible fixture head 17 fixed on the horizontal stage 2, and adjusted by adjusting The knobs 19 in the adjustable micro-feeding device on both sides of the fixture extension table 13 are used to drive the hydraulic feeding device 18, so that the hydraulic feeding device 18 drives the fixture head 17 to slowly move toward the middle until the sample substrate is clamped. At this time, use a spirit level to test Check whether the sample substrate is in the same plane, and make minor adjustments to ensure the uniformity in the subsequent processing and preparation; inject a sufficient amount of deionized water into the micro-injector 7 and adsorb and fix it in the micro-injector On the mounting platform 9, adjust the direction of the axis of the micro-sampler 7 to be parallel to the trapezoidal slide 6 to ensure accurate electro-printing during the droplet falling process. At this point, the pre-processing of preparing the charge density gradient surface by electro-printing is completed;

Afterwards, the adjustable micro horizontal feed device 23 is adjusted to make the horizontal feed connecting rod 22 complete the telescopic action. Micro-feed, thereby driving the horizontal feeding platform 12 to perform micro-feed adjustment in the horizontal direction until the position of the sample substrate to be processed and the axis of the micro-injector 7 are on the same straight line, at this time, adjust the micro-injector carrying platform 9 to the Weber number position of the experimental plan (the positions of different Weber numbers in the present invention correspond to different height values, and the value gradually increases from 10mm to 200mm according to the required increment), and adjust the outer knob of the adjustable micro-feed device at the same time. 20. Rotate the flexible fixture head 17 to the desired angular orientation (generally start from 0° by default in the test, and gradually increase in increments of 8°-10°/time), and slowly push the micro-injector 7 after completing the above actions. Push the rod to release the droplet in a volume of 8-10 μL until the droplet completely hits the sample substrate located on the flexible gripper head 17 . So far, a charge writing action is completed.

Next, according to the above incremental principle, the charge writing process at different positions on the sample substrate is completed by adjusting the adjustable micro-level feeder 23 and the micro-injector mounting platform 9 until all the process parameters preset in the experiment are completed. The preparation of the second "gradient" surface of the electroprinting device, the charge density gradient surface, is completed, that is, the preparation of the monomer with a double gradient wettability surface is completed.

Finally, the above operation process was applied to a large-area substrate, and an array periodic structure with alternating dual gradient wettability surface monomers and untreated areas was prepared by setting the appropriate spacing to meet the requirements of long-distance high-speed droplet transport.

The invention effectively solves the contradictory problem of using the gradient wettability surface to realize the long-distance and high-speed transportation of droplets. While realizing the long-distance and high-speed transportation of the droplets, the invention can flexibly and conveniently pass the metal and other materials with high conductivity to the double The gradient wettable surface substrate is subjected to contact aging treatment to realize the reconstruction of droplet transport path, droplet transport distance and droplet transport speed; in addition, the gradient wettability surface prepared by the present invention has the advantages of durability, mechanical resistance, comprehensive mechanical properties, Stability and other aspects have been greatly improved.

Claims (10)

1. The utility model provides an assist femto second laser and receive manufacturing a device that realizes long-range high-speed liquid drop transportation a little which characterized in that: the device comprises a horizontal objective table (2), wherein the bottom of the horizontal objective table (2) is connected with a shockproof base (1), the upper surface of the horizontal objective table (2) is connected with an electric printing feeding side plate (4), a rib plate (3) is connected between the electric printing feeding side plate (4) and the horizontal objective table (2), and the electric printing feeding side plate (4) is provided with trapezoidal slideways (6) which are arranged at equal intervals and a high-precision scale plate (8) close to one side; a microsyringe carrying platform (9) is arranged on the trapezoidal slideway (6); a microsyringe (7) is fixed on the microsyringe carrying platform (9); a rotatable flexible hydraulic clamp (5) fixed on the horizontal object stage (2) is arranged right below the micro sample injector (7).

2. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 1, is characterized in that: the shaft body direction of the rotatable flexible hydraulic clamp (5) is parallel to the electric printing feeding side plate (4), the rotatable flexible hydraulic clamp is integrally carried on a clamp base (10), horizontal feeding guide rails (11) are symmetrically distributed on the clamp base (10) along the central plane of the clamp base (10), and a horizontal feeding platform (12) is arranged on the horizontal feeding guide rails (11); the right end of the horizontal feeding platform (12) is connected with the output end of the micro differential (21), and the output end of the micro differential (21) is connected with one end of a horizontal feeding connecting rod (22); the other end of the horizontal feeding connecting rod (22) is connected with an adjustable trace horizontal feeding device (23);

the horizontal feeding platform (12) is connected with a clamp extending table (13), the clamp extending table (13) is in a bilateral symmetry structure, and the left side surface and the right side surface of the clamp extending table are connected with an adjustable micro-feeding device fixing frame (14); the outer side of the adjustable micro-feeding device fixing frame (14) is connected with an adjustable micro-feeding device (15), and the inner side is fixed with a locking device (16); the other end of the locking device (16) is connected with a hydraulic feeding device (18); an output shaft of the hydraulic feeding device (18) is connected with the flexible clamp head (17);

an adjustable micro-feeding device inner knob (19) and an adjustable micro-feeding device outer knob (20) are arranged at two ends of the adjustable micro-feeding device (15), the adjustable micro-feeding device inner knob (19) drives the hydraulic feeding device (18) to enable the flexible clamp head (17) to achieve the action of clamping a sample, and the adjustable micro-feeding device outer knob (20) is used for adjusting different angle directions of the flexible clamp head (17).

3. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 1, is characterized in that: the shockproof base (1) is made of industrial high-grade rubber materials.

4. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 1, is characterized in that: the rib plate (3) is symmetrically arranged by taking the central plane of the horizontal object stage (2) as a central axis, and meanwhile, a fillet with the radius of 10mm is arranged at the junction of the rib plate (3) and the electric printing feeding side plate (4).

5. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 1, is characterized in that: the microsyringe (7) is a liquid-phase microsyringe device with the measuring range of 100 mu L, and the axial direction of the microsyringe is parallel to the trapezoidal slideway (6).

6. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 1, is characterized in that: the high-precision scale plate (8) is a measuring tool with the measuring range of 200mm and the precision of micron, the reading of the high-precision scale plate directly corresponds to the numerical values of liquid drops with different heights, and the high-precision scale plate can be converted into corresponding Weber numbers.

7. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 2, is characterized in that: the micro differential (21) is a micro high-precision transmission and is used for regulating and controlling the feeding speed of the horizontal feeding platform (12).

8. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 2, is characterized in that: the adjustable micro-feeding device (15), the locking device (16), the flexible clamp head (17) and the hydraulic feeding device (18) are symmetrically arranged on the left side surface and the right side surface of the clamp extending table (13) by taking the central plane of the clamp extending table as a central axis.

9. The device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation according to claim 2, is characterized in that: the rotatable flexible hydraulic clamp (5) can rotate within the range of-90 degrees to 90 degrees and move in the direction vertical to the trapezoidal slide way (6).

10. The liquid drop transportation process of the device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation is characterized by comprising the following steps of:

i) preparing a gradient periodic microstructure on a sample substrate by femtosecond laser in an arc scanning mode of changing scanning intervals;

II) chemical vapor deposition of SiO on gradient periodic microstructures₂Preparing a first heavy gradient wettability surface by using the nano particles and a low surface energy substance PFOTS;

III) preparing a second heavy 'gradient' surface, namely a charge density gradient surface, on the first heavy gradient wettability surface by a device for assisting femtosecond laser micro-nano manufacturing to realize long-distance high-speed liquid drop transportation, thereby obtaining a double-gradient wettability surface monomer;

VI) preparing a long-distance high-speed liquid drop transportation surface on a large-area sample substrate by regulating and controlling the array spacing of double-gradient wettability surface monomers and repeating the steps I) -III), wherein the liquid drops meet the requirement of high-speed transportation on the double-gradient wettability surface under the dual action of wettability gradient and charge density gradient, and the long-distance transportation is realized by the alternative array arrangement of the double-gradient wettability surface and an untreated area, so that the requirement of long-distance high-speed liquid drop transportation is finally realized.

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