Plasmonic optical tweezers substrate and preparation method

Abstract

The present invention relates to an optical tweezers substrate, in particular, a plasmonic optical tweezers substrate and a preparation method. According to the technical solution provided by the present invention, the plasmonic optical tweezers substrate includes a plasmonic unit and a temperature control unit for controlling the temperature of a local area of ​​the plasmonic unit. The plasmonic unit and the temperature control unit are integrated based on a MEMS process. A temperature control unit is configured to control the temperature of the light spot irradiation area within the plasmonic unit, thereby generating a temperature gradient between the light spot irradiation area of ​​the plasmonic unit and the surrounding environment of the light spot irradiation area. The present invention is based on temperature control based on the Peltier effect, which greatly improves the capture efficiency of optical tweezers and can effectively control thermophoresis. At the same time, it is applicable to the capture of materials above the micron level and is compatible with existing MEMS processes.

Description

Technical Field

[0001] The present invention relates to an optical tweezers substrate, in particular to a plasmon optical tweezers substrate and a preparation method thereof. Background Art

[0002] The specific operating principle of plasmonic tweezers is that when a laser of a specific frequency illuminates the plasmonic tweezers, it generates an evanescent wave, the intensity of which rapidly decreases with increasing distance from the plasmonic tweezers. Calculations using the Maxwell stress tensor method (MST) show that matter within the range of the evanescent wave is subjected to an optical force directed toward the center of the laser spot. This optical force confines the matter within the plasmonic tweezers, achieving capture.

[0003] Since the intensity of the evanescent wave decays rapidly with increasing distance from the plasmonic tweezers, the range of optical force is often limited to below 100nm, and the width of the generated optical force constraint potential well is only in the range of hundreds of nanometers. When the distance between the materials is far or the size of the materials is much larger than the potential well width, the optical force makes it difficult to capture the materials.

[0004] For plasmon tweezers, the reason for thermophoresis is that the local temperature rise caused by laser irradiation causes a temperature gradient in the solution environment. The movement of matter in this temperature field can be expressed by the formula v = -S T ΔT description, where v is the object's velocity vector, S T is the Soret coefficient, and T is the temperature.

[0005] Since the Soret coefficient S T The positive or negative value of Soret coefficient S is affected by many factors such as solvent concentration, material composition, material particle size, ambient temperature, etc. When these factors change, the Soret coefficient S T The positive and negative nature of the Soret coefficient S T Furthermore, when using an optical tweezers system to capture matter, the effects of thermophoresis, which is a byproduct of the high temperatures generated by laser irradiation, are also difficult to predict. Thermophoresis can guide matter toward the high-temperature region where the light spot is located, allowing it to be captured by the optical force, or it can repel matter from the high-temperature region, preventing it from being captured.

[0006] Since laser irradiation only causes the temperature to rise, it is difficult to accurately control the thermophoretic motion by simply adjusting the laser power. In other words, for plasmon optical tweezers, how to effectively capture matter is a technical problem that this technology urgently needs to solve. Summary of the Invention

[0007] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a plasmonic optical tweezers substrate and a preparation method. The substrate is based on the temperature control of the Peltier effect, which greatly improves the capture efficiency of the optical tweezers and can effectively control the thermophoretic motion. At the same time, it is suitable for capturing materials above the micron level and is compatible with existing MEMS processes.

[0008] According to the technical solution provided by the present invention, the plasmon optical tweezers substrate includes a plasmon unit and a temperature control unit for controlling the temperature of a local area of ​​the plasmon unit, wherein:

[0009] The plasmon unit and the temperature control unit are integrated based on the MEMS process. A temperature control unit is configured to control the temperature of the light spot irradiation area within the plasmon unit, so as to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area.

[0010] The temperature control unit performs local temperature control on the plasmon unit based on the temperature control method of the Peltier effect;

[0011] The temperature control unit includes one or more temperature control matrices, wherein when the temperature control unit includes multiple temperature control matrices, the multiple temperature control matrices are distributed in an array;

[0012] A temperature control substrate is used to control the temperature of a region in the plasmon unit that corresponds to the temperature control substrate.

[0013] The temperature control substrate includes a temperature control insulating support layer, a first Peltier effect temperature control unit prepared on the temperature control insulating support layer, and a first Peltier effect unit protection heat conductive layer for supporting a plasmon unit, wherein:

[0014] The first Peltier effect temperature control unit is located in the first Peltier effect unit protective heat conductive layer;

[0015] The first Peltier effect temperature control unit includes a plurality of first doped polysilicon bodies and second doped polysilicon bodies that are alternately arranged, and the first doped polysilicon bodies and the second doped polysilicon bodies are connected in series with a metal connecting conductor;

[0016] The Seebeck coefficient of the first doped polysilicon body is the same as or different from the Seebeck coefficient of the second doped polysilicon body.

[0017] The temperature control substrate includes a second Peltier effect temperature control unit and a second Peltier effect unit protection heat conducting layer for supporting the plasmon unit, wherein:

[0018] The second Peltier effect temperature control unit includes a polycrystalline silicon substrate, a graphene upper diaphragm adaptively connected to the first surface of the polycrystalline silicon substrate, and a graphene lower diaphragm adaptively connected to the second surface of the polycrystalline silicon substrate;

[0019] The polysilicon substrate includes a diaphragm connection area, a diaphragm contact area distributed on the outer circle of the diaphragm connection area, and a regional isolation groove penetrating the polysilicon substrate, wherein the diaphragm connection area is isolated from the diaphragm contact area by the regional isolation groove;

[0020] The graphene upper diaphragm is conductively connected to the diaphragm connection area on the first surface of the polysilicon substrate, and the outer edge of the graphene upper diaphragm is connected to the upper diaphragm insulating support layer, and the upper diaphragm insulating support layer covers the diaphragm contact area on the first surface of the polysilicon substrate;

[0021] The graphene lower diaphragm is conductively connected to the diaphragm connection area on the second surface of the polysilicon substrate, and the outer edge of the graphene lower diaphragm is connected to the lower diaphragm insulating connection layer, and the lower diaphragm insulating connection layer covers the diaphragm contact area on the second surface of the polysilicon substrate;

[0022] The regional isolation groove of the polysilicon substrate is sealed by using the graphene upper diaphragm and the graphene lower diaphragm to form a temperature-controlled thermal insulation cavity;

[0023] The second Peltier effect unit protects the heat-conducting layer and is in contact with the graphene upper diaphragm.

[0024] The temperature control substrate includes a third Peltier effect temperature control unit and a third Peltier effect unit protection heat conducting layer for supporting the plasmon unit, wherein:

[0025] The third Peltier effect temperature control unit includes a pair of temperature control subunits, and the temperature control subunits are isolated by unit isolation grooves;

[0026] The temperature control sub-unit includes a polycrystalline silicon film body and a graphene sub-membrane adapted to the polycrystalline silicon film body. The graphene sub-membrane is connected to the sub-membrane insulating support body on the polycrystalline silicon film body and is in conductive contact with the polycrystalline silicon film body. The contact between the graphene sub-membrane, the sub-membrane insulating support body and the polycrystalline silicon film body is used to form a sub-unit insulation cavity.

[0027] The conductive contact region between the graphene sub-membrane and the polysilicon film body is adjacent to the unit isolation trench, and the graphene sub-membrane is in contact with and connected to the third Peltier effect unit protective heat conductive layer.

[0028] The plasmon unit includes a nanoforest and metal particles prepared on nanopillars in the nanoforest.

[0029] A method for preparing a plasmonic optical tweezers substrate, wherein:

[0030] An integrated plasmon unit and a temperature control unit are prepared based on the MEMS process, and the temperature control unit is used to control the temperature of a local area within the plasmon unit.

[0031] When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes:

[0032] Providing a first supporting substrate, and disposing a temperature-controlled insulating supporting layer on the first supporting substrate;

[0033] A first Peltier effect temperature control unit is prepared on the temperature control insulating support layer, wherein the first Peltier effect temperature control unit includes a plurality of first doped polysilicon bodies and second doped polysilicon bodies arranged alternately, and the first doped polysilicon bodies and the second doped polysilicon bodies are connected in series with a metal connecting conductor;

[0034] The Seebeck coefficient of the first doped polysilicon body is the same as or different from the Seebeck coefficient of the second doped polysilicon body;

[0035] preparing a first Peltier effect unit protective heat-conducting layer, wherein the first Peltier effect unit protective heat-conducting layer presses the first Peltier effect temperature control unit onto the temperature control insulating support layer;

[0036] separating the first supporting substrate from the temperature-controlling insulating supporting layer;

[0037] A plasmon unit is prepared on the first Peltier effect unit protective heat conductive layer.

[0038] When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes:

[0039] providing a second supporting substrate, and preparing a second supporting substrate sacrificial layer on the second supporting substrate;

[0040] preparing a polysilicon substrate on the second supporting base sacrificial layer;

[0041] Patterning the polysilicon substrate to prepare a diaphragm connection region, a diaphragm contact region, and a regional isolation trench penetrating the polysilicon substrate on a first surface of the polysilicon substrate, wherein the diaphragm connection region is isolated from the diaphragm contact region by the regional isolation trench;

[0042] preparing an upper diaphragm insulating support layer on the diaphragm contact region of the polysilicon substrate;

[0043] Providing a graphene upper membrane and transferring the graphene upper membrane to the first surface of a polycrystalline silicon substrate, wherein the graphene upper membrane is conductively connected to a membrane connection region on the first surface of the polycrystalline silicon substrate, an outer edge of the graphene upper membrane is connected to an upper membrane insulating support layer, and a closed region isolation groove of the graphene upper membrane is separated from a notch corresponding to the first surface of the polycrystalline silicon substrate;

[0044] Preparing a second Peltier effect unit protective heat-conducting layer on the graphene upper membrane, and preparing a plasmon unit on the second Peltier effect unit protective heat-conducting layer;

[0045] Separating the second supporting base and the second supporting base sacrificial layer from the polycrystalline silicon substrate, and etching the second surface of the polycrystalline silicon substrate to form a diaphragm connection area and a diaphragm contact area distributed around the diaphragm connection area on the second surface of the polycrystalline silicon substrate;

[0046] preparing a lower diaphragm insulating connection layer in a diaphragm contact region of the polysilicon substrate;

[0047] A graphene lower diaphragm is provided and transferred to the second surface of a polycrystalline silicon substrate, wherein the graphene lower diaphragm is conductively connected to a diaphragm connection area on the second surface of the polycrystalline silicon substrate, an outer edge of the graphene lower diaphragm is connected to the lower diaphragm insulating connection layer, and a closed area of ​​the graphene lower diaphragm isolates the groove from the notch corresponding to the second surface of the polycrystalline silicon substrate.

[0048] When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes:

[0049] Providing a third supporting substrate, and preparing a third supporting substrate sacrificial layer on the third supporting substrate;

[0050] forming a polysilicon film layer on the third supporting base sacrificial layer;

[0051] Patterning the polysilicon film layer to obtain a polysilicon film window penetrating the polysilicon film layer and a polysilicon film body distributed in the polysilicon film window;

[0052] Filling the polysilicon film layer window with an insulating spacer, and arranging a sub-membrane insulating support on the polysilicon film body;

[0053] Providing a graphene sub-membrane and transferring the graphene sub-membrane onto a polycrystalline silicon film body, wherein the graphene sub-membrane is connected to a sub-membrane insulating support body on the polycrystalline silicon film body and is in conductive contact with the polycrystalline silicon film body, and utilizing the contact and cooperation between the graphene sub-membrane, the sub-membrane insulating support body, and the polycrystalline silicon film body to form a sub-unit thermal insulation cavity;

[0054] preparing a third Peltier effect unit protective thermal conductive layer, wherein the third Peltier effect unit protective thermal conductive layer is in contact with the graphene sub-membrane and the insulating spacer;

[0055] Preparing a plasmon unit on the third Peltier effect unit protective heat conductive layer;

[0056] The third supporting substrate, the third supporting substrate sacrificial layer and the insulating spacer are peeled off.

[0057] Advantages of the present invention: The plasmon unit and the temperature control unit are integrated based on the MEMS process. The temperature control unit is configured for the light spot irradiation area within the plasmon unit to control the temperature of the light spot irradiation area, so as to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area. The generated temperature gradient can be used to generate thermophoresis and Rayleigh-Bénard convection, that is, temperature control based on the Peltier effect, which greatly improves the capture efficiency of the optical tweezers and can effectively control the thermophoresis. At the same time, it is suitable for capturing materials above the micron level and is compatible with existing MEMS processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figures 1 to 8 This is a cross-sectional view of the specific process steps of the first embodiment of the present invention, wherein:

[0059] Figure 1 4 is a cross-sectional view of the first supporting substrate of the present invention.

[0060] Figure 2 This is a cross-sectional view of the heat-conducting layer prepared in the present invention.

[0061] Figure 3 This is a cross-sectional view of the temperature-controlled insulating support layer prepared in the present invention.

[0062] Figure 4 This is a cross-sectional view of the present invention after obtaining metal connection to the lower conductor.

[0063] Figure 5 This is a cross-sectional view of the first doped polysilicon body and the second doped polysilicon body prepared in the present invention.

[0064] Figure 6 This is a cross-sectional view of the first Peltier effect unit protective heat-conducting layer prepared in the present invention.

[0065] Figure 7 This is a cross-sectional view after the first supporting substrate is peeled off according to the present invention.

[0066] Figure 8 This is a cross-sectional view of the plasmon unit prepared in the present invention.

[0067] Figures 9 to 18This is a cross-sectional view of the specific process steps of the second embodiment of the present invention, wherein:

[0068] Figure 9 is a cross-sectional view of the second supporting substrate of the present invention.

[0069] Figure 10 This is a cross-sectional view of the second supporting base sacrificial layer prepared in the present invention.

[0070] Figure 11 This is a cross-sectional view of the polysilicon substrate prepared in the present invention.

[0071] Figure 12 This is a cross-sectional view of the polysilicon substrate after patterning according to the present invention.

[0072] Figure 13 This is a cross-sectional view of the upper diaphragm insulating support layer prepared in the present invention.

[0073] Figure 14 This is a cross-sectional view of the present invention after the graphene upper membrane is transferred to the first surface of the polysilicon substrate.

[0074] Figure 15 This is a cross-sectional view of the plasmon unit prepared in the present invention.

[0075] Figure 16 This is a cross-sectional view of the second surface of the polysilicon substrate after etching the second supporting substrate and the second supporting substrate sacrificial glass layer according to the present invention.

[0076] Figure 17 This is a cross-sectional view of the lower diaphragm insulating connection layer prepared in the present invention.

[0077] Figure 18 This is a cross-sectional view of the present invention after the graphene lower membrane is transferred to the second surface of the polysilicon substrate.

[0078] Figures 19 to 26 This is a cross-sectional view of the specific process steps of the third embodiment of the present invention, wherein:

[0079] Figure 19 4 is a cross-sectional view of a third supporting substrate of the present invention.

[0080] Figure 20 This is a cross-sectional view of the third supporting base sacrificial layer prepared in the present invention.

[0081] Figure 21 This is a cross-sectional view of the polysilicon film layer prepared by the present invention.

[0082] Figure 22 This is a cross-sectional view of the polysilicon film layer after patterning according to the present invention.

[0083] Figure 23This is a cross-sectional view of the insulating isolator prepared in the present invention.

[0084] Figure 24 This is a cross-sectional view of the present invention after the graphene sub-membrane is transferred to the polysilicon film body.

[0085] Figure 25 This is a cross-sectional view of the plasmon unit prepared in the present invention.

[0086] Figure 26 This is a cross-sectional view after the third supporting substrate, the third supporting substrate sacrificial layer, and the insulating spacer are peeled off according to the present invention.

[0087] Figure 27 This is a cross-sectional view of an embodiment of the present invention in which the graphene sub-membrane is also in conductive contact with the polysilicon on the sub-membrane insulating support.

[0088] Explanation of the accompanying symbols: 1-first supporting base, 2-thermal conductive layer, 3-temperature-controlled insulating support layer, 4-metal-connected first conductor, 5-first doped polysilicon body, 6-second doped polysilicon body, 7-first Peltier effect unit protective thermal conductive layer, 8-metal particles, 9-nanopillars, 10-second supporting base, 11-second supporting base sacrificial layer, 12-polysilicon base, 13-diaphragm contact area, 14-regional isolation groove, 15-diaphragm connection area, 16-upper diaphragm insulating support layer, 17-graphene upper diaphragm, 18-second Peltier effect unit Protective thermal conductive layer, 19-lower diaphragm insulating connection layer, 20-graphene lower diaphragm, 21-third supporting substrate, 22-third supporting substrate sacrificial layer, 23-polysilicon membrane layer, 24-polysilicon membrane body, 25-polysilicon membrane layer window, 26-membrane body connection area, 27-sub-diaphragm insulating support body, 28-insulating isolator, 29-graphene sub-diaphragm, 30-sub-unit thermal insulation cavity, 31-third Peltier effect unit protective thermal conductive layer, 32-unit isolation trench isolation, 33-metal connection second conductor and 34-polysilicon on the sub-diaphragm insulating support body. DETAILED DESCRIPTION

[0089] The present invention will be further described below with reference to specific drawings and embodiments.

[0090] In order to significantly improve the capture efficiency of optical tweezers and effectively control thermophoretic motion, and at the same time be applicable to the capture of materials above the micron level, a plasmon optical tweezers substrate, in one embodiment of the present invention, includes a plasmon unit and a temperature control unit for controlling the temperature of a local area of ​​the plasmon unit, wherein:

[0091] The plasmon unit and the temperature control unit are integrated based on the MEMS process. A temperature control unit is configured to control the temperature of the light spot irradiation area within the plasmon unit, so as to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area.

[0092] For the plasmonic optical tweezers substrate, in one embodiment of the present invention, it includes at least a plasmonic unit and a temperature control unit for temperature control of the plasmonic unit. The plasmonic unit has the ability to realize the plasmonic effect. The temperature control unit can be used to control the temperature of a local area of ​​the plasmonic unit. The temperature control of the local area of ​​the plasmonic unit is to use the temperature control unit to control the temperature of a predetermined local area. The temperature control generally may include heating control or cooling control of the predetermined local area. The position distribution of the predetermined local area in the plasmonic unit and the form of temperature control can be selected according to actual needs, so as to meet the actual application scenario, that is, to meet the requirements of improving the capture efficiency.

[0093] It can be seen from the above description that when using optical tweezers to capture positions, relying solely on optical force cannot meet the purpose of capture efficiency and the like. When using a plasmon unit to capture matter, it is necessary to irradiate the laser beam into the plasmon unit to obtain a light spot irradiation area in the plasmon unit. In one embodiment of the present invention, a temperature control unit and a plasmon unit are prepared and integrated based on a MEMS process, and the temperature of the light spot irradiation area is controlled by configuring a temperature control unit to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area. When a temperature gradient is generated between the light spot irradiation area and the surrounding environment, thermophoresis and Rayleigh-Bénard convection are generated in the light spot irradiation area, so as to utilize the generated thermophoresis and Rayleigh-Bénard convection to improve the ability of the light spot irradiation area to capture matter.

[0094] During implementation, a temperature gradient is generated between the illuminated area and its surroundings, specifically a temperature difference between the illuminated area and the surrounding environment. Rayleigh-Bénard convection occurs because the temperature difference creates a density difference in the solution, which then forms convection under the influence of gravity. Therefore, the resulting Rayleigh-Bénard convection promotes the capture of substances in the illuminated area. Regarding the generated thermophoretic motion, if the direction of the thermophoretic motion is toward the center of the light spot, it promotes the capture of substances; otherwise, it hinders the capture of substances.

[0095] When the temperature control unit is integrated with the plasmon unit, the distribution position of the temperature control unit can be determined. Therefore, when capturing matter, the light spot irradiation area needs to correspond to the temperature control unit, so that when the temperature control unit is used to perform local area temperature control, a temperature gradient can be generated between the light spot irradiation area and the surrounding environment of the light spot irradiation area, that is, the light spot irradiation area generally needs to be the above-mentioned predetermined local area.

[0096] From the above description, it can be seen that the present invention can effectively control the thermophoretic movement when using optical tweezers to capture substances through a temperature control unit, and can solve the problem that an optical potential well that is too narrow is difficult to use for capturing substances above the micron level, thereby improving the efficiency of capturing substances and being suitable for capturing substances above the micron level.

[0097] In one embodiment of the present invention, the temperature control unit performs local temperature control on the plasmon unit based on a temperature control method of the Peltier effect;

[0098] The temperature control unit includes one or more temperature control matrices, wherein when the temperature control unit includes multiple temperature control matrices, the multiple temperature control matrices are distributed in an array;

[0099] A temperature control substrate is used to control the temperature of a region in the plasmon unit that corresponds to the temperature control substrate.

[0100] In order to be compatible with MEMS technology and effectively achieve temperature control, the temperature control unit is based on the Peltier effect. The Peltier effect temperature control specifically refers to the fact that when a current passes through a loop composed of conductors of different materials, in addition to generating irreversible Joule heat, heat absorption and heat release will occur at the joints of different conductors depending on the direction of the current. After two different materials are bonded together and energized, the heat generated per unit area is Q = (π a -π b )*I, where Q is heat, I is current, and π a is the Peltier coefficient of the first material, π b is the Peltier coefficient of the second material, π=ST, S is the Seebeck coefficient of the material, and T is the temperature in Kelvin.

[0101] In a specific implementation, the predetermined local region within the plasmon unit may be one or more. Therefore, the temperature control unit includes one or more temperature control substrates. Specifically, the temperature control substrates perform temperature control based on the Peltier effect, and the temperature control substrates correspond directly to the predetermined local region. Generally, when multiple temperature control substrates are included, the multiple temperature control substrates are arranged in an array. The specific arrangement of the array is determined so as to correspond directly to the predetermined local region within the plasmon unit.

[0102] In practice, a single temperature-controlled substrate can be used to control the temperature of a specific, predetermined local area. As described above, this temperature control can be achieved by heating or cooling. Generally, during a single capture operation, one or more temperature-controlled substrates can be used to control the temperature of the corresponding, predetermined local area, with the specific temperature gradient between the illuminated area and the surrounding environment being generated.

[0103] Specifically, the intensity and coverage of Rayleigh-Bénard convection are proportional to the range of heating / cooling. Therefore, at the beginning of material capture, multiple temperature-controlled matrix units surrounding the center of the spot illumination area are activated to generate strong Rayleigh-Bénard convection, rapidly guiding particles farther away through Rayleigh-Bénard convection to the area of ​​the activated temperature-controlled matrix units. As the particle to be captured approaches the area of ​​the active temperature-controlled matrix units, the temperature-controlled matrices at the edges of the spot illumination center are gradually deactivated, allowing the temperature-controlled matrices further inward to attract the particle to the area of ​​the spot illumination area through thermophoresis. This process is repeated until the particle enters the temperature-controlled matrix corresponding to the spot illumination area. Of course, if the particle to be captured is initially closer to the center of the spot illumination area, only the temperature-controlled matrix corresponding to the spot illumination area can be activated.

[0104] As can be seen from the above description, the temperature control substrate generally adopts a process form compatible with the MEMS process. The temperature control substrate is specifically based on the temperature control that can meet the Peltier effect. The specific implementation form of the temperature control substrate is described in detail below.

[0105] In one embodiment of the present invention, the temperature control substrate includes a temperature control insulating support layer 3, a first Peltier effect temperature control unit prepared on the temperature control insulating support layer 3, and a first Peltier effect unit protection thermal conductive layer 7 for supporting the plasmon unit, wherein:

[0106] The first Peltier effect temperature control unit is located in the first Peltier effect unit protection heat conductive layer 7;

[0107] The first Peltier effect temperature control unit includes a plurality of alternately arranged first doped polysilicon bodies 5 and second doped polysilicon bodies 6, and the first doped polysilicon bodies 5 and the second doped polysilicon bodies 6 are connected in series with a metal connecting conductor;

[0108] The Seebeck coefficient of the first doped polysilicon body 5 is the same as or different from the Seebeck coefficient of the second doped polysilicon body 6 .

[0109] Figure 8The temperature control substrate of this embodiment is shown in the figure. The temperature control insulating support layer 3 is generally made of an insulating and thermally conductive material, such as silicon nitride. The specific type of material of the temperature control insulating support layer 3 can be selected according to actual needs. The first Peltier effect temperature control unit specifically refers to the first embodiment based on the Peltier effect temperature control unit. In this embodiment, the first Peltier effect temperature control unit is prepared on the temperature control insulating support layer 3, and the first Peltier effect temperature control unit is pressed onto the temperature control insulating support layer 3 by the second Peltier effect unit protective thermal conductive layer 7. The first Peltier effect temperature control unit is located within the first Peltier effect unit protective thermal conductive layer 7. At this time, while the first Peltier effect unit protective thermal conductive layer 7 is used to protect the first Peltier effect temperature control unit, heat transfer between the first Peltier effect temperature control unit and the plasmon unit can also be achieved.

[0110] Figure 8 In the embodiment, the first Peltier effect temperature control unit includes a first doped polycrystalline silicon body 5 and a second doped polycrystalline silicon body 6. The Seebeck coefficient of the first doped polycrystalline silicon body 5 is the same as or different from the Seebeck coefficient of the second doped polycrystalline silicon body 6. For example, the first doped polycrystalline silicon body 5 and the second doped polycrystalline silicon body 6 may both be N-type doped polycrystalline silicon, both be P-type doped polycrystalline silicon, or respectively be N-type doped polycrystalline silicon and P-type doped polycrystalline silicon. When the first doped polycrystalline silicon body 5 and the second doped polycrystalline silicon body 6 are N-type doped polycrystalline silicon and P-type doped polycrystalline silicon, they need to be arranged alternately so as to be connected in series.

[0111] Specifically, the metal connection conductor includes a first metal connection conductor 4 and a second metal connection conductor 33. The first metal connection conductor 4 and the second metal connection conductor 33 can be made of commonly available aluminum materials, specifically to enable the first doped polysilicon body 5 and the second doped polysilicon body 6 to be connected in series. As can be seen from the above description, during temperature control, depending on the direction of current flow, the junctions between the first metal connection conductor 4 and the second metal connection conductor 33 and the first doped polysilicon body 5 and the second doped polysilicon body 6, respectively, will release or absorb heat. During heat release, the heat is conducted to the plasmon unit through the first Peltier effect unit protective thermal conductive layer 7; during heat absorption, the heat from the plasmon unit is absorbed by the first Peltier effect unit protective thermal conductive layer 7.

[0112] From the above description, a plurality of Peltier effect functional areas will exist simultaneously in the temperature control substrate composed of the first doped polysilicon body 5 , the second doped polysilicon body 6 and the metal connector. Figure 8 In the embodiment, a heat-conducting layer 2 can be further disposed on the temperature-control insulating support layer 3. The heat-conducting layer 2 can dissipate heat from the temperature-control insulating support layer 3 to the outside, depending on whether the heat-conducting layer 2 can meet the temperature control requirements of the predetermined local area. The heat-conducting layer 2 and the first Peltier effect temperature control unit are located on either side of the temperature-control insulating support layer 3.

[0113] right Figure 8The plasmonic optical tweezers substrate in Figures 1 to 8 The process steps shown are used to prepare the integrated plasmon unit and the temperature control unit based on the MEMS process. Therefore, when the integrated plasmon unit and the temperature control unit are prepared based on the MEMS process, the preparation method includes:

[0114] Providing a first supporting substrate 1, and arranging a temperature-controlled insulating supporting layer 3 on the first supporting substrate 1;

[0115] A first Peltier effect temperature control unit is prepared on the temperature control insulating support layer 3, wherein the first Peltier effect temperature control unit includes a plurality of alternately arranged first doped polysilicon bodies 5 and second doped polysilicon bodies 6, and the first doped polysilicon bodies 5 and the second doped polysilicon bodies 6 are connected in series by a metal connecting conductor;

[0116] The Seebeck coefficient of the first doped polysilicon body 5 is the same as or different from the Seebeck coefficient of the second doped polysilicon body 6 ;

[0117] Prepare a first Peltier effect unit protective heat-conducting layer 7, wherein the first Peltier effect unit protective heat-conducting layer 7 presses the first Peltier effect temperature control unit onto the temperature control insulating support layer 3;

[0118] Separating the first supporting substrate 1 from the temperature-control insulating supporting layer 3;

[0119] A plasmon unit is prepared on the first Peltier effect unit protective heat conducting layer 7 .

[0120] Figure 1 In the embodiment, the first supporting substrate 1 can be a common silicon substrate. As can be seen from the above description, when the heat conducting layer 2 is required to conduct heat, the heat conducting layer 2 needs to be prepared on the first supporting substrate 1, and the heat conducting layer 2 covers the first supporting substrate 1, such as Figure 2 shown. Figure 3 In order to prepare the temperature-controlling insulating support layer 3 on the heat-conducting layer 2, the temperature-controlling insulating support layer 3 and the heat-conducting layer 2 can be prepared by using the existing commonly used process.

[0121] In order to prepare the first Peltier effect temperature control unit, Figure 4 In the embodiment, a plurality of metal connection first conductors 4 are firstly provided on the temperature control insulating support layer 3. The metal connection first conductors 4 can be made of common metal materials, such as aluminum. After the metal connection first conductors 4 are prepared, a first doped polysilicon body 5 and a second doped polysilicon body 6 are prepared on the metal connection first conductors 4. That is, the lower ends of the first doped polysilicon body 5 and the lower ends of the second doped polysilicon body 6 are electrically connected to the metal connection first conductors 4. Figure 5 shown.

[0122] In order to realize the connection of the first doped polysilicon body 5 and the second doped polysilicon body 6 in series, it is necessary to prepare a metal connection second conductor 33. The distribution position of the metal connection second conductor 33 is based on the conditions for connecting the first doped polysilicon body 5 and the second doped polysilicon body 6 in series. Figure 6 After the metal connection second conductor 33 is prepared, a first Peltier effect unit protective heat conductive layer 7 is also prepared. The first Peltier effect unit protective heat conductive layer 7 is used to cover the first doped polysilicon body 5 and the second doped polysilicon body 6 connected in series and encapsulate them on the temperature control insulating support layer 3, as shown. Figure 6 shown.

[0123] After preparing the first Peltier effect unit protective thermal conductive layer 7, the first supporting substrate 1 is first peeled off. Specifically, the peeling of the first supporting substrate 1 can be achieved by using existing commonly used process methods. After the first supporting substrate 1 is peeled off, the plasmon unit is prepared on the first Peltier effect unit protective thermal conductive layer 7.

[0124] Figure 8 Figure 2 shows an embodiment of a plasmonic unit, in which a nanoforest is formed on the first Peltier effect unit's protective thermal conductive layer 7, and metal particles 8 are formed on the nanopillars 9 within the nanoforest. In other words, the nanoforest and metal particles 8 form a plasmonic unit. The nanoforest and metal particles 8 can be prepared using commonly used techniques in the art. Of course, the plasmonic unit can also be implemented in other forms, and the specific implementation can be selected based on actual application requirements.

[0125] Figure 18 , a second embodiment of the temperature control substrate is shown. In this case, the temperature control substrate includes a second Peltier effect temperature control unit and a second Peltier effect unit protective heat conducting layer 18 for supporting the plasmon unit, wherein:

[0126] The second Peltier effect temperature control unit includes a polycrystalline silicon substrate 12, a graphene upper diaphragm 17 adapted to be connected to a first surface of the polycrystalline silicon substrate 12, and a graphene lower diaphragm 20 adapted to be connected to a second surface of the polycrystalline silicon substrate 12;

[0127] The polysilicon substrate 12 includes a diaphragm connection area 15, a diaphragm contact area 13 distributed around the diaphragm connection area 15, and a regional isolation trench 14 that passes through the polysilicon substrate 12. The diaphragm connection area 15 is isolated from the diaphragm contact area 13 by the regional isolation trench 14.

[0128] The graphene upper diaphragm 17 is conductively connected to the diaphragm connection area 15 on the first surface of the polysilicon substrate 12, and the outer edge of the graphene upper diaphragm 17 is connected to the upper diaphragm insulating support layer 16, and the upper diaphragm insulating support layer 16 covers the diaphragm contact area 13 on the first surface of the polysilicon substrate 12;

[0129] The graphene lower diaphragm 20 is conductively connected to the diaphragm connection area 15 on the second surface of the polysilicon substrate 12, and the outer edge of the graphene lower diaphragm 20 is connected to the lower diaphragm insulating connection layer 19, and the lower diaphragm insulating connection layer 19 covers the diaphragm contact area 13 on the second surface of the polysilicon substrate 12;

[0130] The regional isolation groove 14 of the polysilicon substrate 12 is sealed by using the graphene upper diaphragm 17 and the graphene lower diaphragm 20 to form a temperature-controlled heat-insulating cavity;

[0131] The second Peltier effect unit protective heat conducting layer 18 is in contact with and connected to the graphene upper membrane 17 .

[0132] Specifically, the polysilicon substrate 12 is doped polysilicon, such as N-type doped polysilicon. The polysilicon substrate 12 generally has a first surface and a second surface, and the first surface and the second surface are two surfaces corresponding to the polysilicon substrate 12. The graphene upper diaphragm 17 is adaptively connected to the first surface of the polysilicon substrate 12, and the graphene lower diaphragm 20 is adaptively connected to the second surface of the polysilicon substrate 12. The adaptive connection specifically refers to an electrical connection only with the diaphragm connection area 15 of the polysilicon substrate 12. As can be seen from the above description, heat release or heat absorption can be generated at the junction of the graphene upper diaphragm 17, the graphene lower diaphragm 20 and the diaphragm connection area 15, thereby achieving the purpose of temperature control.

[0133] The second Peltier effect unit protective thermal conductive layer 18 contacts the graphene upper membrane 17, providing protection and heat conduction. The graphene upper membrane 17 and the graphene lower membrane 20 seal the regional isolation trenches 14 within the polysilicon substrate 12, forming a temperature-controlled, insulating cavity to prevent localized temperature loss caused by heat dissipation.

[0134] During operation, current flows from the graphene upper diaphragm 17 through the diaphragm contact area 15 of the polysilicon substrate 12 and out through the graphene lower diaphragm 20. The graphene upper diaphragm 17, the diaphragm contact area 15 of the polysilicon substrate 12, and the graphene lower diaphragm 20 form a loop. Furthermore, the graphene lower diaphragm 20 further supports the diaphragm connection area 15 of the polysilicon substrate 12.

[0135] Figure 18 The plasmonic optical tweezers in Figures 9 to 18The specific preparation process steps shown are used to prepare the integrated plasmon unit and the temperature control unit based on the MEMS process. Specifically, when the integrated plasmon unit and the temperature control unit are prepared based on the MEMS process, the preparation method includes:

[0136] Providing a second supporting substrate 10 and preparing a second supporting substrate sacrificial layer 11 on the second supporting substrate 10;

[0137] Preparing a polysilicon substrate 12 on the second supporting base sacrificial layer 11;

[0138] The polysilicon substrate 12 is patterned to form a diaphragm connection region 15, a diaphragm contact region 13, and a regional isolation trench 14 penetrating the polysilicon substrate 12 on a first surface of the polysilicon substrate 12, wherein the diaphragm connection region 15 is isolated from the diaphragm contact region 13 by the regional isolation trench 14;

[0139] An upper diaphragm insulating support layer 16 is formed on the diaphragm contact region 13 of the polysilicon substrate 12;

[0140] Providing a graphene upper membrane 17 and transferring the graphene upper membrane 17 to the first surface of the polycrystalline silicon substrate 12, wherein the graphene upper membrane 17 is conductively connected to the membrane connection area 15 on the first surface of the polycrystalline silicon substrate 12, the outer edge of the graphene upper membrane 17 is connected to the upper membrane insulating support layer 16, and the graphene upper membrane 17 closes the regional isolation groove 14 and the notch corresponding to the first surface of the polycrystalline silicon substrate 12;

[0141] A second Peltier effect unit protective heat-conducting layer 18 is prepared on the graphene upper membrane 17, and a plasmon unit is prepared on the second Peltier effect unit protective heat-conducting layer 18;

[0142] Separating the second supporting substrate 10 and the second supporting substrate sacrificial layer 11 from the polycrystalline silicon substrate 12, and etching the second surface of the polycrystalline silicon substrate 12 to form a diaphragm connection area 15 and a diaphragm contact area 13 distributed around the diaphragm connection area 15 on the second surface of the polycrystalline silicon substrate 12;

[0143] A lower diaphragm insulating connection layer 19 is formed on the diaphragm contact region 13 of the polysilicon substrate 12;

[0144] A graphene lower diaphragm 20 is provided and transferred to the second surface of the polysilicon substrate 12, wherein the graphene lower diaphragm 20 is conductively connected to the diaphragm connection area 15 on the second surface of the polysilicon substrate 12, the outer edge of the graphene lower diaphragm 20 is connected to the lower diaphragm insulating connection layer 19, and the graphene lower diaphragm 20 closes the regional isolation groove 14 and the notch corresponding to the second surface of the polysilicon substrate 12.

[0145] Figure 9The second supporting base 10 is shown in FIG. The second supporting base 10 can be specifically described with reference to the first supporting base 1. The second supporting base sacrificial layer 11 is prepared by using common technical means in this technical field. The second supporting base sacrificial layer 11 is covered on the second supporting base 10. Figure 10 As shown, the second supporting base sacrificial layer 11 can generally be a silicon dioxide layer.

[0146] A polysilicon substrate 12 is prepared on the second supporting base sacrificial layer 11, such as Figure 11 As shown, as described above, the polysilicon substrate 12 can be N-doped polysilicon, which can be prepared by using commonly used technical means in this technical field.

[0147] Figure 12 In the embodiment, the polysilicon substrate 12 is patterned to obtain a diaphragm connection area 15 located in the center, a diaphragm contact area 13 located outside the diaphragm connection area 15, and a regional isolation groove 14 penetrating the polysilicon substrate 12. That is, the diaphragm connection area 15 is formed by using the polysilicon substrate 12 in the center, and the diaphragm contact area 13 is formed by using the edge area. Figure 12 In the embodiment, the height of the diaphragm contact area 13 is lower than the height of the diaphragm connection area 15 .

[0148] Figure 13 In the embodiment, an upper diaphragm insulating support layer 16 is formed on the diaphragm contact region 13. The upper diaphragm insulating support layer 16 can be a silicon nitride layer. The upper diaphragm insulating support layer 16 only covers the diaphragm contact region 13 and does not cover the diaphragm connection region 15. After the upper diaphragm insulating support layer 16 is formed, the height of the entire diaphragm contact region 13 is consistent with the height of the diaphragm connection region 15.

[0149] Figure 14 In the process, the graphene upper membrane 17 is transferred onto the polycrystalline silicon substrate 12. The graphene upper membrane 17 can be prepared using existing processes. When transferred onto the polycrystalline silicon substrate 12, the graphene upper membrane 17 is in conductive contact with the membrane connection region 15. The graphene upper membrane 17 is insulated and isolated from the membrane contact region 13 by the upper membrane insulating support layer 16. In addition, the graphene upper membrane 17 also covers the notch of the regional isolation trench 14. To improve the stability and reliability of the graphene upper membrane 17 on the polycrystalline silicon substrate 12, the graphene upper membrane 17 can be placed on the polycrystalline silicon substrate 12 by bonding.

[0150] Pure graphene materials have a low Seebeck coefficient due to the overlap of their conduction band and valence band. Under normal circumstances, it is only 80μV / K, which is much smaller than the Seebeck coefficient of commonly used thermoelectric materials such as polycrystalline silicon. However, the energy band of graphene can be changed through methods such as doping, chemical modification, lateral heterogeneous extension, and electrical doping (applying external voltage). The degree of change can be evaluated by chemical potential. In specific implementation, the graphene membrane needs to undergo treatments including but not limited to nitrogen, phosphorus, and germanium ion implantation, chemical modification, or lateral heteroepitaxial growth to change its chemical potential and achieve a high Seebeck coefficient. The specific method and process for achieving a high Seebeck coefficient of graphene can be selected as needed, so as to meet the requirements of obtaining a graphene upper membrane 17 with a high Seebeck coefficient and the following graphene lower membrane 20 and graphene sub-membrane 29.

[0151] Figure 15 In the process, a second Peltier effect unit protective thermal conductive layer 18 is prepared on the above-mentioned graphene upper membrane 17. After the second Peltier effect unit protective thermal conductive layer 18 is prepared, a plasmon unit is prepared on the second Peltier effect unit protective thermal conductive layer 18. Figure 15 The plasmon unit prepared in Figure 8 The plasmon unit is consistent with that shown in , and the details can be referred to the above description.

[0152] After the plasmon unit is prepared, the second supporting substrate 10 and the second supporting substrate sacrificial layer 11 are peeled off. Figure 16 At this time, the notch of the regional isolation groove 14 corresponding to the second surface of the polysilicon substrate 12 is in an open state.

[0153] The second surface of the polysilicon substrate 12 is etched. During the etching, a patterned state is formed with the first surface of the polysilicon substrate 12. At this time, the diaphragm connection area 15 and the diaphragm contact area 13 formed on the second surface of the polysilicon substrate 12 are obtained. Thereafter, a lower diaphragm insulating connection layer 19 is deposited and prepared. The lower diaphragm insulating connection layer 19 is located in the diaphragm contact area 13 on the second surface of the polysilicon substrate 12. The lower diaphragm insulating connection layer 19 is used to make the corresponding surfaces of the diaphragm contact area 13 and the diaphragm connection area 15 flush. Figure 17 shown.

[0154] To form a temperature-controlled, thermally insulated cavity, a lower graphene membrane 20 is transferred to the second surface of the polycrystalline silicon substrate 12. The lower graphene membrane 20 is electrically connected to the membrane connection area 15 on the second surface of the polycrystalline silicon substrate 12. The lower graphene membrane 20 is also connected to the membrane contact area 13 on the second surface of the polycrystalline silicon substrate 12 via a lower membrane insulating connection layer 19. By isolating the trench 14 by enclosing the graphene lower membrane 20 and the graphene upper membrane 17, a temperature-controlled, thermally insulated cavity is formed.

[0155] As can be seen from the above description, when current is loaded and passed through the graphene upper membrane 17 and the polysilicon substrate 12, a Peltier effect of heat release or heat absorption is generated at the junction of the graphene upper membrane 17 and the membrane connection area 15 of the polysilicon substrate 12. At this time, the temperature of the corresponding predetermined local area of ​​the plasmon unit can be controlled.

[0156] Compared with the temperature control using doped polysilicon to form the Peltier effect, graphene has a higher Seebeck coefficient. Therefore, when the graphene upper membrane 17 and the polysilicon substrate 12 are used to perform local temperature control on the plasmon unit, sufficient cooling or heating effects can be generated in a small area at the micron level, effectively regulating the local temperature and achieving the purpose of improving the efficiency of material capture.

[0157] Figure 26 The third embodiment of the temperature control substrate of the present invention is shown. In this case, the temperature control substrate includes a third Peltier effect temperature control unit and a third Peltier effect unit protective heat conductive layer 31 for supporting the plasmon unit, wherein:

[0158] The third Peltier effect temperature control unit includes a pair of temperature control subunits, and the temperature control subunits are isolated by a unit isolation groove 32;

[0159] The temperature control subunit includes a polysilicon film body 24 and a graphene sub-diaphragm 29 adapted to the polysilicon film body 24. One end of the graphene sub-diaphragm 29 is connected to the sub-diaphragm insulating support body 27 on the polysilicon film body 24, and the other end of the graphene sub-diaphragm 29 is in conductive contact with the polysilicon film body 24. The contact and cooperation between the graphene sub-diaphragm 29, the sub-diaphragm insulating support body 27 and the polysilicon film body 24 are used to form a sub-unit insulation cavity.

[0160] The conductive contact region between the graphene sub-membrane 29 and the polysilicon film body 24 is adjacent to the cell isolation trench 32 , and the graphene sub-membrane 29 is in contact with the third Peltier effect unit protection heat conduction layer 31 .

[0161] In practice, paired temperature control subunits specifically refer to being fabricated in pairs, with each temperature control subunit operating independently. The two temperature control units are isolated by a unit isolation trench 32, effectively minimizing mutual influence during temperature control. The method for achieving temperature control by utilizing the graphene sub-diaphragm 29 in conjunction with the polysilicon membrane 24 can be referenced to the aforementioned description of achieving temperature control by utilizing the graphene upper membrane 17 in conjunction with the polysilicon substrate 12.

[0162] Figure 26 The plasmonic optical tweezers in Figures 19 to 26 The specific preparation process steps shown are used to prepare, specifically,

[0163] When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes:

[0164] Providing a third supporting substrate 21 and preparing a third supporting substrate sacrificial layer 22 on the third supporting substrate 21;

[0165] forming a polysilicon film layer 23 on the third supporting base sacrificial layer 22;

[0166] The polysilicon film layer 23 is patterned to obtain a polysilicon film window 25 penetrating the polysilicon film layer 23 and a polysilicon film body 24 distributed in the window of the polysilicon film layer 25;

[0167] Fill the polysilicon film window 25 with an insulating spacer 28, and set a sub-membrane insulating support 27 on the polysilicon film 28;

[0168] Providing a graphene sub-membrane 29 and transferring the graphene sub-membrane 29 onto the polycrystalline silicon film body 24, wherein the graphene sub-membrane 29 is connected to the sub-membrane insulating support body 27 on the polycrystalline silicon film body 24 and is in conductive contact with the polycrystalline silicon film body 24, and utilizing the contact and cooperation between the graphene sub-membrane 29, the sub-membrane insulating support body 27 and the polycrystalline silicon film body 24 to form a sub-unit thermal insulation cavity 30;

[0169] Prepare a third Peltier effect unit protective thermal conductive layer 31, wherein the third Peltier effect unit protective thermal conductive layer 31 is in contact with the graphene sub-membrane 29 and the insulating spacer 28;

[0170] Prepare a plasmon unit on the third Peltier effect unit protection heat conductive layer 31;

[0171] The third supporting substrate 21 , the third supporting substrate sacrificial layer 22 and the insulating spacer 28 are peeled off.

[0172] Figure 19 FIG. 2 shows a third supporting base 21, and a third supporting base sacrificial layer 22 is covered on the third supporting base 21. Figure 20 The details of the third supporting base 21 and the third supporting base sacrificial layer 22 can refer to the above description.

[0173] The polysilicon film layer 23 is prepared by a polysilicon deposition process commonly used in the art. The polysilicon film layer 23 covers the third supporting base sacrificial layer 22. Figure 21 shown.

[0174] The polysilicon film layer 23 is patterned, that is, the polysilicon film layer 23 is selectively masked and etched to obtain polysilicon film window 25 that penetrates the polysilicon film layer 23. At this time, a pair of polysilicon film bodies 24 are also obtained. After patterning, the area outside the polysilicon film window 25 is thinned to form a protruding film body connection area 26. The film body connection area 26 is adjacent to the polysilicon film window 25. Figure 22 As shown. Figure 22 It can be seen that in cross section, the polysilicon film body 24 has a protruding film body connection area 26 at the end close to the polysilicon film layer window 25 , and the height of the remaining portion is smaller than that of the film body connection area 26 .

[0175] Using deposition or other process forms, an insulating spacer 28 is filled in the polysilicon film window 25. The height of the insulating spacer 28 is greater than the thickness of the film body connection area 26. The insulating spacer 28 can be made of a material such as silicon dioxide. The insulating spacer 28 fills the polysilicon film window 25. After obtaining the insulating spacer 28, a sub-membrane insulating support 27 is also deposited on the polysilicon film body 24 to prepare the sub-membrane insulating support 27. The sub-membrane insulating support 27 can generally be a silicon dioxide layer. In the cross-sectional view, the sub-membrane insulating support 27 and the film body connection area 26 are respectively located at the two ends of the polysilicon film body 24. At this time, the two ends of the polysilicon film body 24 can be at the same horizontal height, as shown in FIG. Figure 23 shown.

[0176] A graphene sub-membrane 29 is provided. The graphene sub-membrane 29 is generally sized to fit the polysilicon film 24. The function of the graphene sub-membrane 29 is consistent with that of the graphene upper membrane 17 described above. After the graphene sub-membrane 29 is transferred to the polysilicon film 24, the polysilicon film 29 is connected to the sub-membrane insulating support 27 and is in conductive contact with the polysilicon film 24, that is, in conductive contact with the film connection region 26. At this point, the junction between the graphene sub-membrane 29 and the film connection region 26 can achieve temperature control via the Peltier effect.

[0177] In specific implementation, for the two temperature control sub-units, the junction of the graphene sub-membrane 29 and the membrane body connection area 26 is separated by an insulating spacer 28, such as Figure 24 As shown in the figure, the height of the junction between the graphene sub-membrane 29 and the membrane body connection area 26 is less than the height of the insulating isolator 28, that is, a triangular cover plate is formed on the polysilicon membrane body 24, and at this time, the sub-unit insulation cavity 30 can be formed.

[0178] A third Peltier effect unit protection heat conducting layer 31 is prepared on the graphene sub-membrane 29 and the insulating spacer 28. The third Peltier effect unit protection heat conducting layer 31 can refer to the description of the second Peltier effect unit protection heat conducting layer 18, etc. Figure 25, an embodiment of a plasmon unit is shown, which adopts the combination of nano forest and metal particles 8.

[0179] The third support substrate 21, the third support substrate sacrificial layer 22 and the insulating spacer 28 are peeled off by the common technical means in this technical field. At this time, the cell isolation trench isolation 32 is formed behind the glass insulating spacer 28. Figure 26 shown.

[0180] As can be seen from the above description, the two temperature control sub-units are independent of each other, and temperature control can be performed after current is passed through the graphene sub-membrane 29 and the polysilicon film body 24 in each temperature control unit.

[0181] also, Figure 27 Another implementation is provided in Figure 26 Compared with the diagram, polysilicon 34 on the sub-diaphragm insulating support is provided on the sub-diaphragm insulating support 27, and the polysilicon 34 on the sub-diaphragm insulating support is in conductive contact with the graphene sub-diaphragm 29. At this time, the two ends of the graphene sub-diaphragm 29 are respectively connected to the polysilicon 34 on the sub-diaphragm insulating support and the polysilicon film body 24. Thus, for a temperature control sub-unit, when the current flows along the direction of the polysilicon film body 24-graphene sub-diaphragm 29-polysilicon 34 on the sub-diaphragm insulating support, a cooling / heating state opposite to the center will be generated at the edge, thereby further improving the temperature control effect of the plasmon unit.

[0182] From the above description, we can see that Figure 27 In the figure, for the paired temperature-controlled sub-units, the area where the cell isolation trench 32 is formed is the center, and the area where the graphene sub-membrane 29 contacts the polysilicon 34 on the sub-membrane insulating support is the edge. According to the Peltier effect, the direction of temperature control in the area where the graphene sub-membrane 29 contacts the polysilicon 34 is opposite to the direction of temperature control in the area where the graphene sub-membrane 29 contacts the polysilicon 34 on the sub-membrane insulating support, resulting in opposite cooling / heating states at the edge and at the center.

Claims

1. A plasmonic optical tweezers substrate, characterized in that: It includes a plasmon unit and a temperature control unit for controlling the temperature of a local area of ​​the plasmon unit, wherein: The plasmon unit and the temperature control unit are integrated based on the MEMS process. The temperature control unit is configured to control the temperature of the light spot irradiation area in the plasmon unit, so as to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area. The temperature control unit performs local temperature control on the plasmon unit based on the temperature control method of the Peltier effect; The temperature control unit includes one or more temperature control matrices, wherein when the temperature control unit includes multiple temperature control matrices, the multiple temperature control matrices are distributed in an array; Using a temperature control substrate to control the temperature of a region in the plasmon unit that corresponds to the temperature control substrate; The temperature control substrate includes a temperature control insulating support layer, a first Peltier effect temperature control unit prepared on the temperature control insulating support layer, and a first Peltier effect unit protection heat conductive layer for supporting a plasmon unit, wherein: The first Peltier effect temperature control unit is located in the first Peltier effect unit protective heat conductive layer; The first Peltier effect temperature control unit includes a plurality of first doped polysilicon bodies and second doped polysilicon bodies that are alternately arranged, and the first doped polysilicon bodies and the second doped polysilicon bodies are connected in series with a metal connecting conductor; The Seebeck coefficient of the first doped polysilicon body is the same as or different from the Seebeck coefficient of the second doped polysilicon body.

2. A plasmonic optical tweezers substrate, characterized in that: It includes a plasmon unit and a temperature control unit for controlling the temperature of a local area of ​​the plasmon unit, wherein: The plasmon unit and the temperature control unit are integrated based on the MEMS process. The temperature control unit is configured to control the temperature of the light spot irradiation area in the plasmon unit, so as to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area. The temperature control unit performs local temperature control on the plasmon unit based on the temperature control method of the Peltier effect; The temperature control unit includes one or more temperature control matrices, wherein when the temperature control unit includes multiple temperature control matrices, the multiple temperature control matrices are distributed in an array; Using a temperature control substrate to control the temperature of a region in the plasmon unit that corresponds to the temperature control substrate; The temperature control substrate includes a second Peltier effect temperature control unit and a second Peltier effect unit protection heat conductive layer for supporting the plasmon unit, wherein: The second Peltier effect temperature control unit includes a polycrystalline silicon substrate, a graphene upper diaphragm adaptively connected to the first surface of the polycrystalline silicon substrate, and a graphene lower diaphragm adaptively connected to the second surface of the polycrystalline silicon substrate; The polysilicon substrate includes a diaphragm connection area, a diaphragm contact area distributed on the outer circle of the diaphragm connection area, and a regional isolation groove penetrating the polysilicon substrate, wherein the diaphragm connection area is isolated from the diaphragm contact area by the regional isolation groove; The graphene upper diaphragm is conductively connected to the diaphragm connection area on the first surface of the polysilicon substrate, and the outer edge of the graphene upper diaphragm is connected to the upper diaphragm insulating support layer, and the upper diaphragm insulating support layer covers the diaphragm contact area on the first surface of the polysilicon substrate; The graphene lower diaphragm is conductively connected to the diaphragm connection area on the second surface of the polysilicon substrate, and the outer edge of the graphene lower diaphragm is connected to the lower diaphragm insulating connection layer, and the lower diaphragm insulating connection layer covers the diaphragm contact area on the second surface of the polysilicon substrate; The regional isolation groove of the polysilicon substrate is sealed by using the graphene upper diaphragm and the graphene lower diaphragm to form a temperature-controlled thermal insulation cavity; The second Peltier effect unit protects the heat-conducting layer and is in contact with the graphene upper diaphragm.

3. A plasmonic optical tweezers substrate, characterized in that: It includes a plasmon unit and a temperature control unit for controlling the temperature of a local area of ​​the plasmon unit, wherein: The plasmon unit and the temperature control unit are integrated based on the MEMS process. The temperature control unit is configured to control the temperature of the light spot irradiation area in the plasmon unit, so as to generate a temperature gradient between the light spot irradiation area of ​​the plasmon unit and the surrounding environment of the light spot irradiation area. The temperature control unit performs local temperature control on the plasmon unit based on the temperature control method of the Peltier effect; The temperature control unit includes one or more temperature control matrices, wherein when the temperature control unit includes multiple temperature control matrices, the multiple temperature control matrices are distributed in an array; Using a temperature control substrate to control the temperature of a region in the plasmon unit that corresponds to the temperature control substrate; The temperature control substrate includes a third Peltier effect temperature control unit and a third Peltier effect unit protection heat conductive layer for supporting the plasmon unit, wherein: The third Peltier effect temperature control unit includes a pair of temperature control subunits, and the temperature control subunits are isolated by unit isolation grooves; The temperature control subunit includes a polycrystalline silicon film body and a graphene sub-membrane adapted to the polycrystalline silicon film body, the graphene sub-membrane is connected to the sub-membrane insulating support body on the polycrystalline silicon film body and is in conductive contact with the polycrystalline silicon film body, and the contact and cooperation between the graphene sub-membrane, the sub-membrane insulating support body and the polycrystalline silicon film body are utilized to form a sub-unit insulation cavity; The conductive contact region between the graphene sub-membrane and the polysilicon film body is adjacent to the unit isolation trench, and the graphene sub-membrane is in contact with and connected to the third Peltier effect unit protective heat conductive layer.

4. The plasmonic optical tweezers substrate according to claim 3, wherein: The plasmon unit includes a nanoforest and metal particles prepared on nanopillars in the nanoforest.

5. A method for preparing a plasmonic optical tweezers substrate, characterized in that: Used to prepare the plasmonic optical tweezers substrate according to any one of claims 1 to 4, wherein An integrated plasmon unit and a temperature control unit are prepared based on the MEMS process, and the temperature control unit is used to control the temperature of a local area within the plasmon unit.

6. The method for preparing a plasmonic optical tweezers substrate according to claim 5, wherein: When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes: Providing a first supporting substrate, and disposing a temperature-controlled insulating supporting layer on the first supporting substrate; A first Peltier effect temperature control unit is prepared on the temperature control insulating support layer, wherein the first Peltier effect temperature control unit includes a plurality of first doped polysilicon bodies and second doped polysilicon bodies arranged alternately, and the first doped polysilicon bodies and the second doped polysilicon bodies are connected in series with a metal connecting conductor; The Seebeck coefficient of the first doped polysilicon body is the same as or different from the Seebeck coefficient of the second doped polysilicon body; preparing a first Peltier effect unit protective heat-conducting layer, wherein the first Peltier effect unit protective heat-conducting layer presses the first Peltier effect temperature control unit onto the temperature control insulating support layer; separating the first supporting substrate from the temperature-controlling insulating supporting layer; A plasmon unit is prepared on the first Peltier effect unit protective heat conductive layer.

7. The method for preparing a plasmonic optical tweezers substrate according to claim 5, wherein: When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes: providing a second supporting substrate, and preparing a second supporting substrate sacrificial layer on the second supporting substrate; preparing a polysilicon substrate on the second supporting base sacrificial layer; Patterning the polysilicon substrate to prepare a diaphragm connection region, a diaphragm contact region, and a regional isolation trench penetrating the polysilicon substrate on a first surface of the polysilicon substrate, wherein the diaphragm connection region is isolated from the diaphragm contact region by the regional isolation trench; preparing an upper diaphragm insulating support layer on the diaphragm contact region of the polysilicon substrate; Providing a graphene upper membrane and transferring the graphene upper membrane to the first surface of a polycrystalline silicon substrate, wherein the graphene upper membrane is conductively connected to a membrane connection region on the first surface of the polycrystalline silicon substrate, an outer edge of the graphene upper membrane is connected to an upper membrane insulating support layer, and a closed region isolation groove of the graphene upper membrane is separated from a notch corresponding to the first surface of the polycrystalline silicon substrate; Preparing a second Peltier effect unit protective heat-conducting layer on the graphene upper membrane, and preparing a plasmon unit on the second Peltier effect unit protective heat-conducting layer; Separating the second supporting base and the second supporting base sacrificial layer from the polycrystalline silicon substrate, and etching the second surface of the polycrystalline silicon substrate to form a diaphragm connection area and a diaphragm contact area distributed around the diaphragm connection area on the second surface of the polycrystalline silicon substrate; preparing a lower diaphragm insulating connection layer in a diaphragm contact region of the polysilicon substrate; A graphene lower diaphragm is provided and transferred to the second surface of a polycrystalline silicon substrate, wherein the graphene lower diaphragm is conductively connected to a diaphragm connection area on the second surface of the polycrystalline silicon substrate, an outer edge of the graphene lower diaphragm is connected to the lower diaphragm insulating connection layer, and a closed area of ​​the graphene lower diaphragm isolates the groove from the notch corresponding to the second surface of the polycrystalline silicon substrate.

8. The method for preparing a plasmonic optical tweezers substrate according to claim 5, wherein: When preparing an integrated plasmon unit and a temperature control unit based on a MEMS process, the preparation method includes: Providing a third supporting substrate, and preparing a third supporting substrate sacrificial layer on the third supporting substrate; forming a polysilicon film layer on the third supporting base sacrificial layer; Patterning the polysilicon film layer to obtain a polysilicon film window penetrating the polysilicon film layer and a polysilicon film body distributed in the polysilicon film window; Filling the polysilicon film layer window with an insulating spacer, and arranging a sub-membrane insulating support on the polysilicon film body; Providing a graphene sub-membrane and transferring the graphene sub-membrane onto a polycrystalline silicon film body, wherein the graphene sub-membrane is connected to a sub-membrane insulating support body on the polycrystalline silicon film body and is in conductive contact with the polycrystalline silicon film body, and utilizing the contact and cooperation between the graphene sub-membrane, the sub-membrane insulating support body, and the polycrystalline silicon film body to form a sub-unit thermal insulation cavity; preparing a third Peltier effect unit protective heat conductive layer, wherein the third Peltier effect unit protective heat conductive layer is in contact with the graphene sub-membrane and the insulating spacer; Preparing a plasmon unit on the third Peltier effect unit protective heat conductive layer; The third supporting substrate, the third supporting substrate sacrificial layer and the insulating spacer are peeled off.

Images