Multi-beam laser interference photoetching system

Abstract

The utility model relates to a multi-beam laser interference photoetching system which comprises a high-power laser, five high-reflectivity mirrors, two semi-reflecting and semi-transmitting mirrors, three groups of 1 / 2 wave plates and polaroids, thirteen lens supports and a sample table, the high-power laser emits a beam of light, the beam of light is divided into three coherent light beams by the five high-reflectivity mirrors and the two semi-reflecting and semi-transmitting mirrors, and the three coherent light beams are connected with the sample table. The relative positions of the five high-reflectivity mirrors and the two semi-reflecting and semi-transmitting mirrors have a certain corresponding relation with the incident angle and the space angle of the three coherent light beams, the light intensity energy density and the polarization state of the coherent light beams are changed by adjusting the angles of the three groups of 1 / 2 wave plates and the polaroids, and the light intensity energy density and the polarization state of the coherent light beams are changed through the incident angle, the space angle and the polarization state. The period and the morphology of the patterned micro-nano structure are changed, and the characteristic size of the patterned micro-nano structure is changed by changing the light intensity energy density and the polarization state, so that the process is simplified, and the control capability of the patterned micro-nano structure is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of patterned micro-nano structures, in particular to a multi-beam laser interference lithography system. Background Art

[0002] Based on the coherence principle of laser, dual-beam interference can form a periodic structure in the interference field, and its minimum structural period is close to half the laser wavelength. Therefore, the dual-beam interference system is often used to prepare periodic stripe structures. For example, Chinese patent document announcement number CN218332292U discloses a laser interference lithography system, including: a laser, a 45° total reflection mirror, a cubic beam splitter prism, an attenuation plate, a beam expander, a reflector, a collimating lens, a shear plate collimator, a substrate clamping frame, an electric turntable, an angle fine-tuning wedge mirror, and a phase compensation wedge mirror, which are used to prepare silicon-based microlens arrays. Chinese patent document announcement number CN207833218U discloses a laser interference lithography system for preparing a cell substrate with a dual-periodic nanostructure, including: a laser, a nanoarray element splitting system, a high reflection mirror and a modulator, and a stripe interference pattern is formed on the sample stage. Chinese patent document announcement number CN206557526U discloses a laser interference lithography optical system, including: a beam splitter, a reflector, a flexible optical hinge, a half-wave plate and a polarizer; the flexible optical hinge is composed of a light pipe and a joint, and every two light pipes are connected by a joint; a reflector B is arranged inside each joint; a half-wave plate is arranged inside the outlet of each flexible optical hinge, and a polarizer is arranged outside each outlet; after the laser beam is split by the beam splitter, it is reflected by the total reflection mirror and coupled into the optical hinge, and output through the end of the optical hinge. Chinese patent document announcement number CN210281088U discloses a multi-channel laser interference lithography system with the same polarization state, including a triangular pyramid prism, a beam expansion and collimation unit, a beam shaping unit and a polarization state modulation unit, to obtain multi-beam interference fringes.

[0003] The above-mentioned spectroscopic interference systems all have a common problem, which is that they cannot solve the problem of independently controlling the parameters of any beam, and the coherent beam parameters are single, and the control ability of patterned micro-nano structures is limited. The multi-beam laser interference system solves this problem. The number of split beams of the laser beam is determined by the number of spectroscopes. After being split by multiple spectroscopes, the coherent light is gathered together by a reflector to generate an interference field, which can realize the individual setting of the spatial angle, incident angle and polarization state of any coherent beam. At present, the commonly used laser interference systems are mainly double-beam, triple-beam, quad-beam and six-beam interference. Design a suitable interference system, and a periodic patterned structure can be obtained after single or multiple exposures. Double-beam interference exposure is an effective method for preparing one-dimensional structures, which can produce periodic one-dimensional linear or groove structures. Three-beam and four-beam interference can form porous and dot patterns of different shapes. Six-beam interference has a large number of coherent beams, complex optical path construction, and high control difficulty. Therefore, three-beam and four-beam interference have become important tools for manufacturing patterned micro-nano structures. However, the four-beam interference optical path is more complicated than the three-beam optical path, and is easily affected by the incident angle or spatial angle error, resulting in modulation. The use of three-beam interference can not only replace the four-beam interference to form patterns of various shapes and distributions, thereby simplifying the optical path while avoiding modulation problems, but also making it easier to control the shape and distribution of the interference pattern. There are many parameter combinations for non-coplanar three-beam interference, and the interference light field will also change a lot on the Z axis, which can form a larger three-dimensional light field area, thereby realizing the manufacture of three-dimensional patterned micro-nano structures. Utility Model Content

[0004] To this end, the utility model discloses a multi-beam laser interference lithography system, which, through a three-beam interference lithography system design, prepares a patterned micro-nano structure in one step, making the period and morphology controllable and the characteristic size continuously adjustable.

[0005] In order to solve the above technical problems, the utility model provides a multi-beam laser interference lithography system, comprising: a high-power laser, a first high-reflection mirror, a second high-reflection mirror, a first semi-reflective semi-transparent mirror, a third high-reflection mirror, a second semi-reflective semi-transparent mirror, a fourth high-reflection mirror, a fifth high-reflection mirror, a first mirror group, a second mirror group, a third mirror group and a sample stage; the high-power laser is used to emit a beam of laser; the first high-reflection mirror, the second high-reflection mirror, the first semi-reflective semi-transparent mirror and the third high-reflection mirror are used to form a first coherent light beam, the first mirror group is arranged in the emission direction of the first coherent light beam, and the third high-reflection mirror is used to converge the first coherent light beam to the sample stage; the first high-reflection mirror The first high-reflective mirror, the second high-reflective mirror, the first half-reflective half-mirror, the second half-reflective half-mirror and the fourth high-reflective mirror are used to form a second coherent light beam, the second mirror group is arranged in the exit direction of the second coherent light beam, and the fourth high-reflective mirror is used to converge the second coherent light beam to the sample stage; the first high-reflective mirror, the second high-reflective mirror, the first half-reflective half-mirror, the second half-reflective half-mirror and the fifth high-reflective mirror are used to form a third coherent light beam, the third mirror group is arranged in the exit direction of the third coherent light beam, and the fifth high-reflective mirror is used to converge the third coherent light beam to the sample stage; the sample stage is arranged at the focal position of the first coherent light beam, the second coherent light beam and the third coherent light beam.

[0006] In one embodiment of the present invention, the parameters of the high-power laser are: laser wavelength is 1064nm, maximum output energy is 2j, output beam spot diameter is 6mm, single pulse width is 7ns, and repetition frequency is 10kHz.

[0007] In one embodiment of the present invention, the first lens group includes a first 1 / 2 wave plate and a first polarizer, the first 1 / 2 wave plate and the first polarizer are arranged in parallel, and the first 1 / 2 wave plate is located on a side of the first polarizer close to the incident direction of the first coherent light beam.

[0008] In one embodiment of the present invention, the second lens group includes a second 1 / 2 wave plate and a second polarizer, the second 1 / 2 wave plate and the second polarizer are arranged in parallel, and the second 1 / 2 wave plate is located on a side of the second polarizer close to the incident direction of the second coherent light beam.

[0009] In one embodiment of the present invention, the third lens group includes a third 1 / 2 wave plate and a third polarizer, the third 1 / 2 wave plate and the third polarizer are arranged in parallel, and the third 1 / 2 wave plate is located on a side of the third polarizer close to the incident direction of the third coherent light beam.

[0010] In one embodiment of the present invention, the first coherent light beam, the second coherent light beam and the third coherent light beam are non-coplanar coherent light beams that are spatially symmetrically distributed, the spatial angle of the first coherent light beam is 0°, the spatial angle of the second coherent light beam is 120°, and the spatial angle of the third coherent light beam is 240°.

[0011] In one embodiment of the present invention, the incident angles of the first coherent light beam, the second coherent light beam and the third coherent light beam are the same.

[0012] In one embodiment of the present invention, the polarization state combinations of the first coherent light beam, the second coherent light beam and the third coherent light beam are TE-TE-TE and TE-TE-TM.

[0013] In one embodiment of the present invention, the light intensity energy density ratio of the first coherent light beam, the second coherent light beam and the third coherent light beam is 1:1:1.

[0014] In one embodiment of the utility model, the direction in which the first coherent light beam, the second coherent light beam and the third coherent light beam intersect between the focus of the sample stage and the first semi-reflective semi-transmissive mirror is the first direction, the line between the reflection point on the third high-reflective mirror and the reflection point on the fifth high-reflective mirror is the second direction, and the first direction is perpendicular to the second direction.

[0015] The above technical solution of the utility model has the following beneficial effects compared with the prior art:

[0016] The multi-beam laser interference lithography system described in the utility model proposes a three-beam laser interference system design that is conducive to the preparation of patterned micro-nano structures with high duty cycle by regulating the spatial angle and polarization state combination of the coherent beams in the three-beam interference system; a patterned micro-nano structure with a one-step preparation cycle, controllable morphology, and continuously adjustable characteristic size is prepared on the surface of the material, which simplifies the process flow while improving the control ability of the patterned micro-nano structure. The period of the patterned micro-nano structure using the multi-beam laser interference lithography system of the utility model is 3um-12um, and the morphology of the patterned micro-nano structure includes: hole-shaped, point-shaped, columnar, and cone-shaped, and the characteristic size of the patterned micro-nano structure is 200nm-12um. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein

[0018] Figure 1 This is a layout diagram of a multi-beam laser interference lithography system in a preferred embodiment of the utility model;

[0019] Figure 2The periodic dot-shaped micro-nano structure morphology prepared on the stainless steel surface in the preferred embodiment of the utility model Figure 1 ;

[0020] Figure 3 The periodic circular hole-shaped micro-nano structure morphology prepared on the stainless steel surface in the preferred embodiment of the utility model Figure 2 .

[0021] Explanation of the markings in the specification: high-power laser 1, first high-reflective mirror 2, second high-reflective mirror 3, first semi-reflective half-mirror 4, third high-reflective mirror 5, second semi-reflective half-mirror 6, fourth high-reflective mirror 7, fifth high-reflective mirror 8, first 1 / 2 wave plate 9, first polarizer 10, second 1 / 2 wave plate 11, second polarizer 12, third 1 / 2 wave plate 13, third polarizer 14, sample stage 15. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0023] Embodiment 1

[0024] Reference Figure 1As shown, the multi-beam laser interference lithography system of the utility model comprises: a high-power laser 1, a first high-reflection mirror 2, a second high-reflection mirror 3, a first semi-reflective semi-mirror 4, a third high-reflection mirror 5, a second semi-reflective semi-mirror 6, a fourth high-reflection mirror 7, a fifth high-reflection mirror 8, a first mirror group, a second mirror group, a third mirror group and a sample stage 15, wherein the high-power laser 1, the first high-reflection mirror 2, the second high-reflection mirror 3, the first semi-reflective semi-mirror 4, the third high-reflection mirror 5, the second semi-reflective semi-mirror 6, the fourth high-reflection mirror 7, the fifth high-reflection mirror 8, the first mirror group, the second mirror group, the third mirror group and the sample stage 15 are respectively arranged on a lens bracket; the high-power laser 1 is used to emit a beam of laser; the first high-reflection mirror 2, the second high-reflection mirror 3, the first semi-reflective semi-mirror 4 and the third high-reflection mirror 5 are used to form a first coherent light beam, and the first mirror group is arranged at a first phase The first high-reflective mirror 2, the second high-reflective mirror 3, the first semi-reflective half-mirror 4, the second semi-reflective half-mirror 6 and the fourth high-reflective mirror 7 are used to form a second coherent beam, the second mirror group is arranged in the exit direction of the second coherent beam, and the fourth high-reflective mirror is used to converge the second coherent beam to the sample stage 15; the first high-reflective mirror 2, the second high-reflective mirror 3, the first semi-reflective half-mirror 4, the second semi-reflective half-mirror 6 and the fifth high-reflective mirror 8 are used to form a third coherent beam, the third mirror group is arranged in the exit direction of the third coherent beam, and the fifth high-reflective mirror is used to converge the third coherent beam to the sample stage 15; the sample stage 15 is arranged at the focal position of the first coherent beam, the second coherent beam and the third coherent beam.

[0025] The period of the patterned micro-nano structure using the multi-beam laser interference lithography system of the utility model is 5um, the patterned micro-nano structure is a point-shaped micro-nano structure, and the characteristic size of the micro-nano structure is 200nm-5um.

[0026] In the above structure, the parameters of the high-power laser 1 are: laser wavelength is 1064nm, maximum output energy is 2j, output beam spot diameter is 6mm, single pulse width is 7ns, and repetition frequency is 10kHz.

[0027] In the above structure, the first lens group includes a first 1 / 2 wave plate 9 and a first polarizer 10, the first 1 / 2 wave plate 9 and the first polarizer 10 are arranged in parallel, and the first 1 / 2 wave plate 9 is located on the side of the first polarizer 10 close to the incident direction of the first coherent light beam. The second lens group includes a second 1 / 2 wave plate 11 and a second polarizer 12, the second 1 / 2 wave plate 11 and the second polarizer 12 are arranged in parallel, and the second 1 / 2 wave plate 11 is located on the side of the second polarizer 12 close to the incident direction of the second coherent light beam. The third lens group includes a third 1 / 2 wave plate 13 and a third polarizer 14, the third 1 / 2 wave plate 13 and the third polarizer 14 are arranged in parallel, and the third 1 / 2 wave plate 13 is located on the side of the third polarizer 14 close to the incident direction of the third coherent light beam.

[0028] In the above structure, the first coherent light beam, the second coherent light beam and the third coherent light beam are non-coplanar coherent light beams that are spatially symmetrically distributed, the spatial angle of the first coherent light beam is 0°, the spatial angle of the second coherent light beam is 120°, and the spatial angle of the third coherent light beam is 240°. The incident angles of the first coherent light beam, the second coherent light beam and the third coherent light beam are the same. The polarization state combination of the first coherent light beam, the second coherent light beam and the third coherent light beam is TE-TE-TE. The light intensity energy density ratio of the first coherent light beam, the second coherent light beam and the third coherent light beam is 1:1:1. The incident angle, spatial angle, polarization state and light intensity energy density of the first coherent light beam, the second coherent light beam and the third coherent light beam are independent of each other and are regulated separately.

[0029] In the above structure, the direction in which the first coherent light beam, the second coherent light beam and the third coherent light beam intersect at the focus of the sample stage 15 and the first semi-reflective half-mirror 4 is the first direction, and the line between the reflection point on the third high-reflective mirror 5 and the reflection point on the fifth high-reflective mirror 8 is the second direction, and the first direction is perpendicular to the second direction.

[0030] Taking the preparation of dot-shaped micro-nano structures with a period of 5 μm and distributed in a regular triangle on the surface of stainless steel as an example, the preparation method of the multi-beam laser interference lithography system of the utility model includes the following steps:

[0031] First, the incident angle of the first coherent beam is θ1, the incident angle of the second coherent beam is θ2, and the incident angle of the third coherent beam is θ3. It is calculated from the formula that the incident angles of the coherent beams are the same, that is, θ1=θ2=θ3=8°, and the dot-shaped micro-nano structures are distributed in an equilateral triangle. The three coherent beams are symmetrical about the center, and the spatial angles are 0°, 120°, and 240°, respectively.

[0032] Then, according to the known incident angle and space angle, the relative positions of the first high-reflective mirror 2, the second high-reflective mirror 3, the first semi-reflective half-mirror 4, the third high-reflective mirror 5, the second semi-reflective half-mirror 6, the fourth high-reflective mirror 7, the fifth high-reflective mirror 8, the first 1 / 2 wave plate 9, the first polarizer 10, the second 1 / 2 wave plate 11, the second polarizer 12, the third 1 / 2 wave plate 13, the third polarizer 14 and the sample stage 15 are determined, as shown in FIG. Figure 1 shown.

[0033] Finally, the first polarizer 10, the second polarizer 12 and the third polarizer 14 are adjusted to TE, TE and TE respectively, and the angles of the first 1 / 2 wave plate 9, the second 1 / 2 wave plate 11 and the third 1 / 2 wave plate 13 are rotated to make the light intensity energy density of the first coherent light beam, the second coherent light beam and the third coherent light beam the same, which is 0.26 J / cm 2， , a dot-shaped micro-nanostructure with a regular triangle distribution and a period of 5 μm was prepared on the stainless steel surface, such as Figure 2 shown.

[0034] Embodiment 2

[0035] Based on the structure of the first embodiment, the difference from the first embodiment is that the combination of the first polarizer 10, the second polarizer 12 and the third polarizer 14 is TE-TE-TM, the period of the periodic circular hole micro-nano structure is 5um, the incident angles of the three coherent light beams are the same as 8°, and the circular hole-shaped micro-nano structure distributed in an equilateral triangle is prepared on the stainless steel surface, such as Figure 3 shown.

[0036] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention of the utility model.

Claims

1. A multi-beam laser interference lithography system, characterized in that: include: A high-power laser, a first high-reflection mirror, a second high-reflection mirror, a first half-reflection half-transmission mirror, a third high-reflection mirror, a second half-reflection half-transmission mirror, a fourth high-reflection mirror, a fifth high-reflection mirror, a first mirror group, a second mirror group, a third mirror group and a sample stage; The high-power laser is used to emit a beam of laser; The first high-reflection mirror, the second high-reflection mirror, the first semi-reflection semi-mirror and the third high-reflection mirror are used to form a first coherent light beam, the first mirror group is arranged in the emission direction of the first coherent light beam, and the third high-reflection mirror is used to converge the first coherent light beam to the sample stage; The first high-reflection mirror, the second high-reflection mirror, the first half-reflection half-mirror, the second half-reflection half-mirror and the fourth high-reflection mirror are used to form a second coherent light beam, the second mirror group is arranged in the emission direction of the second coherent light beam, and the fourth high-reflection mirror is used to converge the second coherent light beam to the sample stage; The first high-reflection mirror, the second high-reflection mirror, the first half-reflection half-mirror, the second half-reflection half-mirror and the fifth high-reflection mirror are used to form a third coherent light beam, the third mirror group is arranged in the emission direction of the third coherent light beam, and the fifth high-reflection mirror is used to converge the third coherent light beam to the sample stage; The sample stage is arranged at the focal positions of the first coherent light beam, the second coherent light beam and the third coherent light beam.

2. The multi-beam laser interference lithography system according to claim 1, characterized in that: The parameters of the high-power laser are: laser wavelength of 1064nm, maximum output energy of 2j, output beam spot diameter of 6mm, single pulse width of 7ns, and repetition frequency of 10kHz.

3. The multi-beam laser interference lithography system according to claim 1, characterized in that: The first lens group includes a first 1 / 2 wave plate and a first polarizer, the first 1 / 2 wave plate and the first polarizer are arranged in parallel, and the first 1 / 2 wave plate is located on a side of the first polarizer close to the incident direction of the first coherent light beam.

4. The multi-beam laser interference lithography system according to claim 1, characterized in that: The second mirror group includes a second 1 / 2 wave plate and a second polarizer, the second 1 / 2 wave plate and the second polarizer are arranged in parallel, and the second 1 / 2 wave plate is located on a side of the second polarizer close to the incident direction of the second coherent light beam.

5. The multi-beam laser interference lithography system according to claim 1, characterized in that: The third lens group includes a third 1 / 2 wave plate and a third polarizer, the third 1 / 2 wave plate and the third polarizer are arranged in parallel, and the third 1 / 2 wave plate is located on a side of the third polarizer close to the incident direction of the third coherent light beam.

6. The multi-beam laser interference lithography system according to claim 1, characterized in that: The first coherent light beam, the second coherent light beam and the third coherent light beam are non-coplanar coherent light beams that are spatially symmetrically distributed. The spatial angle of the first coherent light beam is 0°, the spatial angle of the second coherent light beam is 120°, and the spatial angle of the third coherent light beam is 240°.

7. The multi-beam laser interference lithography system according to claim 1, characterized in that: The incident angles of the first coherent light beam, the second coherent light beam and the third coherent light beam are the same.

8. The multi-beam laser interference lithography system according to claim 1, characterized in that: The polarization state combinations of the first coherent light beam, the second coherent light beam and the third coherent light beam are TE-TE-TE and TE-TE-TM.

9. The multi-beam laser interference lithography system according to claim 1, characterized in that: The light intensity energy density ratio of the first coherent light beam, the second coherent light beam and the third coherent light beam is 1:1:

1.

10. The multi-beam laser interference lithography system according to claim 1, characterized in that: The direction in which the first coherent light beam, the second coherent light beam and the third coherent light beam intersect at the focus of the sample stage and the first semi-reflective semi-mirror lens is the first direction, the line between the reflection point on the third high-reflective mirror and the reflection point on the fifth high-reflective mirror is the second direction, and the first direction is perpendicular to the second direction.

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