CN104635422A - Nanoimprinting method and device of array micro structure - Google Patents

Abstract

The invention discloses an array type microstructure nanoimprinting method and a device, wherein the array type microstructure nanoimprinting method comprises the following steps: 1) the base material moves to a processing station; 2) the imprinting surface of the mold contacts the base material; 3) Laser irradiating and heating the embossing surface of the mold; 4) embossing; 5) demoulding; 6) moving the base material to the next processing station; 7) repeating steps 2-5. The array type microstructure nano-imprinting method and device of the present invention realize rapid heating and cooling of local micro-regions through laser radiation transmission power; realize heating effects in different sizes of regions by adjusting the parameters of the optical collimation and focusing system; realize the substrate by adjusting the laser power Precise control of material processing temperature; the perfect filling of base material can be realized by adjusting the laser irradiation time, which has the advantages of fast heating speed, precise control of small heating area, and accurate construction of temperature field gradient.

Description

Array microstructure nanoimprint method and device

This application claims the priority of a Chinese patent application with an application date of September 10, 2014, an application number of 201410457892.8, and an invention title of "Array Microstructure Nanoimprinting Method and Device", the entire contents of which are incorporated in this application by reference .

technical field

The invention relates to the field of nanoimprinting manufacturing of arrayed optical microstructures, in particular to a nanoimprinting method and device for arrayed microstructures.

Background technique

The template manufacturing with randomly distributed arrayed holographic patterns is the key to laser anti-counterfeiting technology and special pattern printing technology. . The industry urgently needs an array microstructure processing method with low cost and fast processing performance to realize the industrial application of template manufacturing.

The existing processing methods mainly include: point-by-point laser direct writing technology, interference lithography technology and electron beam direct writing technology. The basic idea of the existing processing method is to use the optical exposure technology based on laser or high-energy particle beam, combined with the point-by-point motion scanning device, to realize the scanning exposure of single point or specific small area, so as to obtain the fine structure pattern of photoresist , and then realize the processing of the entire template structure through steps such as development and graphic transfer. The main disadvantage of the existing method is that the processing efficiency is low, and the photoresist needs to be accurately exposed, which has high requirements on the operation accuracy of the process and equipment, and is subject to many restrictions in practical applications.

Therefore, in view of the above problems, it is necessary to propose a further solution.

Contents of the invention

In view of this, the present invention provides a method and device for nano-imprinting of arrayed microstructures based on laser heating to overcome the deficiencies in the existing template processing methods for arrayed holographic patterns.

In order to achieve the purpose of the above invention, the present invention provides an arrayed microstructure nanoimprinting method, which includes the following steps:

1) Fix the substrate to be nanoimprinted, control the substrate to run to the processing station, and prepare to process the area to be processed of the substrate;

2) controlling the embossed surface of the microstructure mold to be in contact with the region to be processed;

3) Laser irradiating and heating the area corresponding to the area to be processed on the embossing surface of the microstructure mold, and the range of the irradiation area of the laser is 50-1000um;

4) Under laser heating conditions, when the surface temperature of the corresponding area on the embossing surface of the microstructure mold reaches the processing temperature of the substrate, control the embossing surface of the microstructure mold to apply pressure to the area to be processed on the substrate ;

5) After the embossing of the area to be processed on the base material is completed, the laser irradiation is stopped, and after the temperature of the base material drops to the demoulding temperature, the mold is demoulded;

6) Control the base material to move to the next processing station, and prepare to process the next area to be processed of the base material;

7) Repeat steps 2-5 until the nanoimprinting of the substrate is completed.

As an improvement of the nanoimprinting method of the arrayed microstructure of the present invention, the substrate is PMMA, PC and PMMA copolymer.

As an improvement of the arrayed microstructure nanoimprinting method of the present invention, in the step 3, the maximum radiation power of the laser is at least 5W.

As an improvement of the arrayed microstructure nanoimprinting method of the present invention, in the step 3, the laser irradiation heating time is 5 ms-1000 ms.

In order to achieve the purpose of the above invention, the present invention provides an arrayed microstructure nanoimprinting device, which includes: a base, an X-Y axis motion control component, a Z axis motion control component, and a laser-assisted heating component;

The X-Y axis motion control assembly includes: a motion control platform, an X-axis guide rail, a Y-axis guide rail, and a first motor. The Y-axis guide rail is arranged relatively parallel to the base platform, and the two ends of the X-axis guide rail are slidingly arranged On the Y-axis guide rail, the first motor drives the motion control platform to move along the X-axis guide rail and the Y-axis guide rail;

The Z-axis motion control assembly includes: a support beam, a Z-axis guide rail, an embossing head, and a second motor. The support beam is installed on the base, and the Z-axis guide rail is arranged on the support beam. The embossing head is slidably arranged on the Z-axis guide rail, the second motor drives the embossing head to move up and down along the Z-axis guide rail, and the embossing head is located above the motion control platform;

The laser-assisted heating assembly includes: a laser, a beam collimating and focusing assembly, and a fixing frame. The laser-assisted heating assembly is located under the motion control platform, and the laser is arranged toward the motion control platform.

As an improvement of the array type microstructure nanoimprinting device of the present invention, the imprinting head has an imprinting surface on which several microneedle structures are formed.

As an improvement of the arrayed microstructure nanoimprinting device of the present invention, a vibration isolator is further arranged under the base.

As an improvement of the array microstructure nanoimprinting device of the present invention, the laser is a continuous output laser.

Compared with the prior art, the beneficial effects of the present invention are: the arrayed microstructure nanoimprinting method and device of the present invention transmit power through laser radiation to realize rapid heating and cooling of local micro-regions; Parameters to achieve the heating effect of different size areas; by adjusting the laser power to achieve precise control of the processing temperature of the base material; through the adjustment of the laser irradiation time to achieve perfect filling of the base material, with fast heating speed, precise control of small heating areas, and temperature field gradient construction Accurate and other advantages.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic flow diagram of a specific embodiment of the arrayed microstructure nanoimprinting method of the present invention;

Fig. 2 is the photo of the arrayed grating structure processed and formed in embodiment 1;

Fig. 3 is an enlarged view of the circled part in Fig. 2;

Fig. 4 is the dimple structure photo that processing forms among the embodiment 2;

Fig. 5 is the profile test curve at the dimple place in Fig. 4;

Fig. 6 is the photograph of the holographic pattern that processing forms in embodiment 3;

Figure 7 is an enlarged view of the text part in Figure 6;

FIG. 8 is a schematic perspective view of a specific embodiment of the arrayed microstructure nanoimprinting device of the present invention;

Fig. 9 is a side view of the circled part in Fig. 8 .

Detailed ways

The technical solutions in the embodiments of the present invention will be described in detail below, obviously, the described embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The array type microstructure nanoimprinting method and device of the present invention realizes rapid heating and cooling of local micro-regions through laser radiation transmission power; realizes heating effects of different sizes of regions by adjusting the parameters of the beam collimation and focusing components; by adjusting the laser power Accurate control of the processing temperature of the base material is realized; the perfect filling of the base material is realized through the adjustment of the laser irradiation time, which has the advantages of fast heating speed, precise control of the small heating area, and accurate construction of the temperature field gradient.

Specifically, as shown in Figure 1, the method for nanoimprinting of arrayed microstructures of the present invention includes the following steps:

1) Fix the substrate to be nanoimprinted, control the substrate to run to the processing station, and prepare to process the area to be processed of the substrate;

2) controlling the embossed surface of the microstructure mold to be in contact with the region to be processed;

3) Laser irradiating and heating the area corresponding to the area to be processed on the embossing surface of the microstructure mold, and the range of the irradiation area of the laser is 50-1000um;

4) Under laser heating conditions, when the surface temperature of the corresponding area on the embossing surface of the microstructure mold reaches the processing temperature of the substrate, control the embossing surface of the microstructure mold to apply pressure to the area to be processed on the substrate ;

5) After the embossing of the area to be processed on the base material is completed, the laser irradiation is stopped, and after the temperature of the base material drops to the demoulding temperature, the mold is demoulded;

6) Control the base material to move to the next processing station, and prepare to process the next area to be processed of the base material;

7) Repeat steps 2-5 until the nanoimprinting of the substrate is completed.

Wherein, in step 1, the base material is a thermoplastic polymer material such as PMMA, PC, and PMMA copolymer that is easy to process. PMMA refers to polymethyl methacrylate, and PC refers to polycarbonate.

In step 2, when the embossing surface of the microstructure mold is in contact with the area to be processed, it does not apply excessive embossing force to the area to be processed, but touches to achieve alignment.

In step 3, the laser is irradiated from bottom to top on the area corresponding to the area to be processed on the embossing surface, and the range of laser irradiation is 50-1000um, so as to realize rapid heating and cooling of local micro areas. In addition, the surface temperature of the embossed surface can be controlled by adjusting the frequency of the laser. The maximum radiation power of the laser is at least 5W. In addition, the irradiation time of the laser beam is controlled by a shutter or a laser switch, and the irradiation time range is preferably 5 ms-1000 ms.

In step 4, when the embossing surface exerts pressure on the area to be processed of the substrate, it needs to maintain a sufficient action time to promote the substrate to fully fill the microstructure on the embossing surface. The processing temperature should be higher than the glass transition temperature of the material and close to the melting temperature of the substrate.

The array microstructure nanoimprinting method of the present invention will be illustrated below in combination with specific examples.

Example 1

PMMA is used as the processing substrate, and the metal nickel material grating with a line width of 500nm is used as the needle tip indenter, and the microstructure grating array template is processed by the needle nanoimprinting method.

Specifically, the processing substrate is fixed on the workbench, and the imprinting surface of the microstructure mold having the above-mentioned needlepoint indenter is controlled to be in contact with the area to be processed; the heating laser is turned on, and the laser beam is focused and irradiated on the surface of the embossing surface , the focal spot size is 200um, the surface temperature rises through energy radiation, and the surface processing temperature is about 200°C.

When the surface temperature of the embossed surface reaches the processing temperature of the substrate, the embossing pressure is applied to the imprinted surface of the microstructure mold, and the pressure is maintained to promote the substrate to fully fill the microstructure, and the holding time is 50ms. After the microstructure filling is completed, the laser radiation is turned off, and the microstructure mold is lifted to realize demoulding.

Control the upper and lower regions to be imprinted on the substrate to run under the imprinted surface of the microstructure mold, and repeat the above steps until the processing of the entire arrayed grating structure is completed.

As shown in Figures 2 and 3, it is a photo of the arrayed grating structure formed by processing and a partially enlarged view. It can be seen from the figure that the arrangement of the processed array structure is consistent with the designed structure, and the line width of the processing result is consistent with the microstructure.

Example 2

The PC is used as the processing base material, the silicon material device with the square boss structure is used as the pinpoint indenter, and the template of the nano pit of the Fabry-Perot optical resonant cavity is processed by the pin nanoimprinting method.

Specifically, the processing substrate is fixed on the workbench, and the imprinting surface of the microstructure mold having the above-mentioned needlepoint indenter is controlled to be in contact with the area to be processed; the heating laser is turned on, and the laser beam is focused and irradiated on the surface of the embossing surface , the focal spot size is 500um, the surface temperature rises through energy radiation, and the surface processing temperature is about 250°C.

When the surface temperature of the embossed surface reaches the processing temperature of the substrate, the embossing pressure is applied to the embossed surface of the microstructure mold, and the pressure is maintained to promote the substrate to fully fill the microstructure, and the holding time is 100ms. After the microstructure filling is completed, the laser radiation is turned off, and the microstructure mold is lifted to realize demoulding.

Controlling the upper and lower regions to be imprinted on the substrate to run under the imprinting surface of the microstructure mold, and repeating the above steps until the processing of the nano pits of the entire Fabry-Perot optical resonant cavity is completed.

As shown in Figures 4 and 5, it is the photo of the pit structure formed by processing and the profile test curve at the pit. It can be seen from the figure that the depth of the processed pit structure is 220nm, which is consistent with the microstructure on the tip indenter, and the fidelity of the processing result is good.

Example 3

The PMMA-MA copolymer is used as the processing substrate, and the metal nickel material grating with a line width of 600nm is used as the needle tip indenter, and the needle nanoimprinting method is used to process the holographic pattern template with a specific pattern.

Specifically, the processing substrate is fixed on the workbench, and the imprinting surface of the microstructure mold having the above-mentioned needlepoint indenter is controlled to be in contact with the area to be processed; the heating laser is turned on, and the laser beam is focused and irradiated on the surface of the embossing surface , the focal spot size is 100um, the surface temperature rises through energy radiation, and the surface processing temperature is about 180°C.

When the surface temperature of the embossed surface reaches the processing temperature of the substrate, the embossed surface of the microstructure mold is controlled to apply embossing pressure, and the pressure is maintained to promote the substrate to fully fill the microstructure, and the holding time is 30ms. After the microstructure filling is completed, the laser radiation is turned off, and the microstructure mold is lifted to realize demoulding.

Control the upper and lower regions to be imprinted on the base material to run under the imprinted surface of the microstructure mold, and repeat the above steps until the processing of the entire boss array structure is completed.

As shown in Figures 6 and 7, they are photos of the processed holographic patterns and their partially enlarged views. It can be seen from the figure that the processed Chinese character pattern structure is neat, the optical effect is good, and it meets the technical requirements of template processing.

As shown in Figure 8, basically the same technical concept, the present invention also provides an arrayed microstructure nanoimprinting device, the arrayed microstructure nanoimprinting device 100 includes: a base 10, an X-Y axis motion control assembly 20, a Z axis Motion control component 30, laser assisted heating component (not shown).

Wherein, the X-Y axis motion control component 20 is used to control the position adjustment of the substrate in a two-dimensional plane. The X-Y axis motion control assembly 20 includes: a motion control platform 21 , an X-axis guide rail 22 , a Y-axis guide rail 23 , and a first motor. The Y-axis guide rails 23 are arranged relatively parallel on the base 10 , thereby forming two guide rails arranged parallel to each other. Both ends of the X-axis guide rail 22 are slidably disposed on the Y-axis guide rail 23 and are kept perpendicular to the Y-axis guide rail 23 . The first motor drives the motion control platform 21 to move along the X-axis guide rail 22 and the Y-axis guide rail 23 . Therefore, when the motion control platform slides along the X-axis guide rail, the motion control platform moves along the X direction in the plane where the X-axis guide rail and the Y-axis guide rail are located. When the motion control platform slides along the Y-axis guide rail, the motion control platform moves along the X-axis guide rail. Move along the Y direction in the plane where the Y-axis guide rail is located.

The Z-axis motion control assembly 30 is used to control the embossing head to move up and down in a direction perpendicular to the plane where the X-axis guide rail and the Y-axis guide rail are located. The Z-axis motion control assembly 30 includes: a support beam 31 , a Z-axis guide rail 32 , an embossing head 33 , and a second motor. The supporting beam 31 is installed on the base 10 , and the Z-axis guide rail 32 is arranged on the supporting beam 31 . Specifically, the Z-axis guide rail 32 can be a strip-shaped protrusion installed on the support beam 31 , or can be a slide groove formed on the support beam 31 . The embossing head 33 is slidably disposed on the Z-axis guide rail 32 and located above the motion control platform 21 . The embossing head 33 has an embossing surface on which a microstructure for pressing and forming is formed, specifically, the microstructure may be formed by several microneedle structures. The second motor provides power for the embossing head 33 to move up and down.

The laser-assisted heating unit is used to provide laser light to irradiate and heat the embossing head. The laser-assisted heating component includes: a laser, a beam collimating and focusing component, and a fixing frame. The laser and the beam collimating and focusing assembly are fixed on the fixed frame, the laser is used to emit the laser beam, and the beam collimating and focusing assembly is used to adjust the range of the laser irradiation area, wherein the range of the laser irradiation area is 50-1000um. Preferably, the laser is a continuous output laser, so that the laser power can be adjusted through the laser to achieve precise control of the processing temperature of the substrate material.

As shown in FIG. 9 , in addition, the laser-assisted heating assembly is located below the motion control platform 21 , and the laser beam emission port of the laser is set toward the motion control platform. In this way, the laser can be irradiated on the embossing surface from bottom to top.

Further, a vibration isolator is arranged under the base 10 , and the vibration isolator plays a role of stabilizing the base to ensure the smooth progress of substrate nanoimprinting.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only contains an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in each embodiment can also be appropriately adapted to form other implementations that can be understood by those skilled in the art.

Claims (8)

1. An array type microstructure nanoimprint method, is characterized in that, described nanoimprint method comprises the steps: 1) Fix the substrate to be nanoimprinted, control the substrate to run to the processing station, and prepare to process the area to be processed of the substrate; 2) controlling the embossed surface of the microstructure mold to be in contact with the region to be processed; 3) Laser irradiating and heating the area corresponding to the area to be processed on the embossing surface of the microstructure mold, and the range of the irradiation area of the laser is 50-1000um; 4) Under laser heating conditions, when the surface temperature of the corresponding area on the embossing surface of the microstructure mold reaches the processing temperature of the substrate, control the embossing surface of the microstructure mold to apply pressure to the area to be processed on the substrate ; 5) After the embossing of the area to be processed on the base material is completed, the laser irradiation is stopped, and after the temperature of the base material drops to the demoulding temperature, the mold is demoulded; 6) Control the base material to move to the next processing station, and prepare to process the next area to be processed of the base material; 7) Repeat steps 2-5 until the nanoimprinting of the substrate is completed. 2 . The array microstructure nanoimprinting method according to claim 1 , wherein the substrate is PMMA, PC and PMMA copolymer. 3 . 3. The nanoimprinting method for arrayed microstructures according to claim 1, characterized in that, in the step 3, the maximum radiation power of the laser is at least 5W. 4 . The array microstructure nanoimprinting method according to claim 1 , characterized in that, in the step 3, the laser irradiation heating time is 5 ms-1000 ms. 5. An array type microstructure nanoimprinting device, characterized in that the array type microstructure nanoimprinting device includes: a base, an X-Y axis motion control component, a Z axis motion control component, and a laser-assisted heating component; The X-Y axis motion control assembly includes: a motion control platform, an X-axis guide rail, a Y-axis guide rail, and a first motor. The Y-axis guide rail is arranged relatively parallel to the base platform, and the two ends of the X-axis guide rail are slidingly arranged On the Y-axis guide rail, the first motor drives the motion control platform to move along the X-axis guide rail and the Y-axis guide rail; The Z-axis motion control assembly includes: a support beam, a Z-axis guide rail, an embossing head, and a second motor. The support beam is installed on the base, and the Z-axis guide rail is arranged on the support beam. The embossing head is slidably arranged on the Z-axis guide rail, the second motor drives the embossing head to move up and down along the Z-axis guide rail, and the embossing head is located above the motion control platform; The laser-assisted heating assembly includes: a laser, a beam collimating and focusing assembly, and a fixing frame. The laser-assisted heating assembly is located under the motion control platform, and the laser is arranged toward the motion control platform. 6 . The array microstructure nanoimprinting device according to claim 5 , wherein the imprinting head has an imprinting surface, and several microneedle structures are formed on the imprinting surface. 7 . 7 . The arrayed microstructure nanoimprinting device according to claim 5 , wherein a vibration isolator is further arranged under the base. 7 . 8 . The array microstructure nanoimprinting device according to claim 5 , wherein the laser is a continuous output laser.