An optical tweezers printing device for processing micro-nano structures

Abstract

The invention provides an optical tweezers printing device for processing micro-nano structures, comprising a laser, a polarizer, a half-wave plate, a beam expander, a liquid crystal spatial light modulator SLM, a first convex lens, a second convex lens, a beam splitter, an objective lens, and a movable stage arranged in sequence along a laser light path; one end of the objective lens is connected to a white light source LED, and the other end is connected to a reflector, and the reflector is sequentially connected to a third convex lens and a charge coupled device CCD. The device is better in processing accuracy and repeatability than a Wiener structure processed by a chemical method, and better in experimental complexity and processing price than focused ion beam lithography and electron beam lithography.

Description

Technical Field

[0001] The invention relates to a printing device, and in particular to an optical tweezers printing device for processing micro-nano structures. Background Art

[0002] At present, the development direction of micro-nano structures is mainly focused on obtaining precise nanostructures through various methods, such as focused ion beam lithography or electron beam lithography, but this method has disadvantages such as high processing cost and complex experiments. Another method is to process micro-nano structures through chemical methods. In this method, the micro-nano structures composed of nanoparticles are random and stable micro-nano structures cannot be obtained. Summary of the invention

[0003] The technical problem to be solved by the present invention is to design an optical tweezers printing device for processing micro-nano structures, and obtain a stable micro-nano structure by capturing nanoparticles and accurately printing any nanostructure on a metal film.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: the present invention provides an optical tweezers printing device for processing micro-nano structures, including a laser, a polarizer, a half-wave plate, a beam expander lens group, a liquid crystal spatial light modulator SLM, a first convex lens, a second convex lens, a beam splitter, an objective lens, and a movable stage connected in sequence along the laser light path; one end of the objective lens is connected to a white light source LED, and the other end is connected to a reflector, and the reflector is connected in sequence to a third convex lens and a charge-coupled device CCD.

[0005] Furthermore, it also includes a control unit, which is connected to the laser, the charge coupled device CCD, the movable stage, and the liquid crystal spatial light modulator SLM.

[0006] Furthermore, the surface of the movable stage is provided with a glass slide for placing the sample to be processed, and the glass slide is a glass slide coated with a gold film.

[0007] Furthermore, a processing solution is arranged on the glass slide, and the processing solution is prepared from a solution containing a cationic surfactant hexadecyltrimethylammonium chloride and gold nanoparticles or a solution containing a cationic surfactant hexadecyltrimethylammonium chloride and medium particles.

[0008] Furthermore, the medium particles are polystyrene microspheres with an average particle size range of 20nm-1μm; and the average particle size range of the gold nanoparticles is 20nm-1μm.

[0009] Furthermore, the beam expander group includes a first beam expander and a second beam expander which are sequentially arranged along the laser transmission direction.

[0010] Furthermore, the first convex lens, the second convex lens, the working mirror surface of the liquid crystal spatial light modulator SLM and the back focal plane of the objective lens together form a 4f system.

[0011] The invention provides an optical tweezers printing device for processing micro-nano structures, which has better processing accuracy and repeatability than Wiener structures processed by chemical methods, and is better than focused ion beam lithography and electron beam lithography in terms of experimental complexity and processing price. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The specific structure of the present invention is described in detail below with reference to the accompanying drawings

[0013] Figure 1 It is the optical path diagram of the experimental system of the present invention;

[0014] Figure 2 It is a schematic diagram of the optical tweezers capture of the present invention.

[0015] The same reference numerals throughout the drawings indicate similar or corresponding features or functions.

[0016] In the figure: 1-laser, 2-polarizer, 3-half-wave plate, 4-first beam expander, 5-second beam expander, 6-liquid crystal spatial light modulator SLM, 7-first convex lens, 8-second convex lens, 9-beam splitter, 10-reflector, 11-third convex lens, 12-charge coupled device CCD, 13-movable stage, 14-white light source LED, 15-objective lens.

[0017] Example 1

[0018] In order to explain the technical content, structural features, achieved objectives and effects of the present invention in detail, the following is a detailed description in conjunction with the implementation methods and the accompanying drawings.

[0019] See also Figure 1 as well as Figure 2 The present invention provides an optical tweezers printing device for processing micro-nano structures, comprising a laser 1, a polarizer 2, a half-wave plate 3, a beam expander lens group, a liquid crystal spatial light modulator SLM6, a first convex lens 7, a second convex lens 8, a beam splitter 9, an objective lens 15, and a movable stage 13; one end of the objective lens 15 is connected to a white light source LED 14, and the other end is connected to a reflector 10, and the reflector 10 is sequentially connected to a third convex lens 11 and a charge coupled device CCD12. The device is also connected to a control unit, and the control unit is connected to the laser 1, the charge coupled device CCD12, the movable stage 13, and the liquid crystal spatial light modulator SLM6.

[0020] In this embodiment, the laser 1 emits a laser, obtains linear polarized light through the polarizer 2, and then adjusts the polarization direction through the half-wave plate 3 to achieve the polarized light required by the liquid crystal spatial light modulator SLM6. After that, the light beam is expanded through the first beam expander 4 and the second beam expander 5 to match the working area of ​​the liquid crystal spatial light modulator SLM6. After the light beam is modulated by the liquid crystal spatial light modulator SLM6, it enters the objective lens 15 through the 4f system, and the light field modulated by the liquid crystal spatial light modulator SLM6 is obtained on the glass substrate coated with a gold film, thereby realizing fast printing. The imaging result is obtained by irradiating the sample with the white light source LED14 in the microscope and then obtaining it on the charge coupled device CCD12. The half-wave plate 3 changes the polarization direction of polarized light so that the polarization direction meets the polarization requirement of the liquid crystal spatial light modulator SLM6. The liquid crystal spatial light modulator SLM6 is used to load the designed hologram, modulate the laser, and obtain the desired light field distribution on the sample. The beam splitter 9 reflects the laser into the objective lens, while allowing the white light source LED14 above the glass slide to pass through. The objective lens 15 focuses the laser onto the glass slide to obtain a sufficiently small spot size. The movable stage 13 is used to carry the glass slide, and the glass slide can be moved by a computer. The processing solution is composed of a cationic surfactant. The invention is prepared from a solution of hexadecyltrimethylammonium chloride and gold nanoparticles or a solution containing a cationic surfactant hexadecyltrimethylammonium chloride and dielectric particles. The function of the white light source LED14 is to illuminate the glass slide so that the printing situation on the glass slide is transmitted to the charge coupled element CCD12 for real-time observation on the computer. The function of the reflector 10 is to reflect the light beam. The function of the third convex lens 11 is to focus the situation on the glass slide onto the charge coupled element CCD12 for imaging. The function of the charge coupled element CCD12 is to obtain a real-time image on the glass slide and display it on the computer.

[0021] The principle of printing is that when the laser beam is focused on the gold film, the gold film absorbs the laser energy and forms a temperature gradient field in the solution above, causing the CTAC molecular micelles and chloride anions in the solution to rearrange, thereby capturing nanoparticles. At the same time, the gold film absorbs the laser energy, forming a local high-temperature zone, and the CTAC molecules on the surface of the captured nanoparticles melt at high temperature, causing the nanoparticles to adhere to the surface of the gold film, thus achieving the printing of nanoparticles on the gold film.

[0022] Example 2

[0023] The control unit is connected to the laser 1 to control the laser power, connected to the charge coupled device CCD12 to display the real-time image of the glass slide, connected to the movable stage 13 to control the movement of the stage, and connected to the liquid crystal spatial light modulator SLM6 to load the hologram and then modulate the light beam.

[0024] Example 3

[0025] The glass slide is a glass slide coated with a gold film. During printing, the nanoparticles in the solution above the gold film are fixed on the surface of the gold film.

[0026] Example 4

[0027] The beam expander group includes a first beam expander 4 and a second beam expander 5 which are sequentially arranged along the laser transmission direction to match the working area of ​​the liquid crystal spatial light modulator SLM6.

[0028] Example 5

[0029] The first convex lens 7, the second convex lens 8, the working mirror of the liquid crystal spatial light modulator SLM6 and the rear focal plane of the objective lens 15 together form a 4f system, which can modulate the spectrum of the laser when necessary and adjust the beam size to match the entrance pupil of the objective lens.

[0030] In summary, the present invention provides an optical tweezers printing device for processing micro-nano structures, which has better processing accuracy and repeatability than Wiener structures processed by chemical methods, and is better than focused ion beam lithography and electron beam lithography in terms of experimental complexity and processing price.

[0031] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for optical printing using an optical tweezers printing device for processing micro-nano structures, characterized in that: The optical tweezers printing device comprises a laser, a polarizer, a half-wave plate, a beam expander, a liquid crystal spatial light modulator SLM, a first convex lens, a second convex lens, a beam splitter, an objective lens, and a movable stage, which are sequentially arranged along a laser light path; one end of the objective lens is connected to a white light source LED, and the other end is connected to a reflector, and the reflector is sequentially connected to a third convex lens and a charge coupled device CCD; a glass slide for placing a sample to be processed is arranged on the surface of the movable stage, the glass slide is a glass slide coated with a gold film, a processing solution layer is arranged on the glass slide, and the processing solution layer is prepared from a solution containing a cationic surfactant hexadecyltrimethylammonium chloride and gold nanoparticles or a solution containing a cationic surfactant hexadecyltrimethylammonium chloride and dielectric particles; Specifically, when performing optical printing: the laser beam emitted by the laser is focused on the gold film through the objective lens. After the gold film absorbs the laser energy, a temperature gradient field is formed in the solution above; the CTAC molecular micelles and chloride anions in the solution are rearranged, thereby capturing nanoparticles. At the same time, the gold film absorbs the laser energy and forms a local high-temperature zone. The CTAC molecules on the surface of the captured nanoparticles melt under high temperature to adhere the nanoparticles to the surface of the gold film, thereby achieving the printing of nanoparticles on the gold film.

2. The optical printing method according to claim 1, characterized in that: It also includes a control unit, which is connected to the laser, the charge coupled device CCD, the movable stage, and the liquid crystal spatial light modulator SLM.

3. The optical printing method as claimed in claim 1, wherein the medium particles are polystyrene microspheres with an average particle size range of 20 nm-1 μm; and the average particle size range of the gold nanoparticles is 20 nm-1 μm. 4 . The optical printing method according to claim 1 , wherein the beam expander group comprises a first beam expander and a second beam expander arranged in sequence along a laser transmission direction.

5. The optical printing method as claimed in claim 1, wherein the first convex lens, the second convex lens, the working mirror surface of the liquid crystal spatial light modulator SLM and the back focal plane of the objective lens together form a 4f system.

Images