A composite structure template suitable for PDMS micro-nano imprinting

Abstract

The utility model discloses a kind of composite structure template suitable for PDMS micro-nano imprinting, which comprises a PDMS sub-template and a jig. The back of the PDMS sub-template is provided with a first positioning recess. The jig is of an annular structure, and a first positioning boss that fits the first positioning recess is provided on the inner ring of the jig. The back of the outer ring of the jig is provided with a second positioning recess. The second positioning recess is used to fit a second positioning boss on the workbench of the imprinting machine. Through the series fitting structure of the "recess-boss", a rigid positioning chain is formed, effectively solving the micron-level displacement and deformation problem of the PDMS soft template due to insecure fixation in the prior art. The utility model has a simple structure and can achieve fast and accurate positioning and installation, significantly improving the alignment accuracy, consistency and uniformity of micro-nano imprinted patterns.

Description

Technical Field

[0001] This utility model relates to the field of micro-nano manufacturing technology, specifically to a composite structure template suitable for PDMS (polydimethylsiloxane) micro-nano imprinting. Background Technology

[0002] Micro-nano imprinting is a highly efficient technique for replicating micro- and nano-structure patterns. PDMS soft stencils are widely used due to their flexibility and ease of demolding. In existing technologies, conventional PDMS soft stencil imprinting systems employ a simple aluminum frame as a support structure. The PDMS soft stencil is laid flat within the frame and placed on the support frame of the imprinting machine. The PDMS soft stencil and the aluminum frame, as well as the aluminum frame and the imprinting machine frame, are fixed solely by planar contact and friction, lacking a precise mechanical positioning structure.

[0003] During the imprinting process, due to the lack of an effective positioning mechanism, micron-level relative displacement and deformation can easily occur between the components, leading to problems such as imprint pattern misalignment, poor consistency, and poor uniformity. Furthermore, this fixing method cannot provide a stable alignment reference for subsequent imprinting processes, limiting further improvements in imprinting accuracy.

[0004] Therefore, there is an urgent need in the field for a PDMS embossing template structure that can achieve precise positioning and eliminate relative displacement between components, in order to solve the embossing defects caused by insecure fixing and misalignment in the prior art. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a composite structure template suitable for PDMS micro-nano imprinting. Through a multi-level self-aligned rigid positioning chain structure, it achieves precise positioning between the PDMS sub-template and the imprinting equipment, fundamentally solving the problems of imprinting pattern offset and poor uniformity.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A composite structure template suitable for PDMS micro / nano imprinting, comprising: The PDMS sub-template has at least one first positioning recess on its back side; The fixture has a ring-shaped structure, and its inner ring is provided with at least one first positioning protrusion that matches the first positioning recess, for fixing the PDMS sub-template. The fixture has at least one second positioning recess on the back of its outer ring. The second positioning recess is used to mate with the second positioning boss on the printing press worktable; A rigid positioning chain is formed by the series connection and engagement of the first positioning recess and the first positioning protrusion, and the second positioning recess and the second positioning protrusion.

[0007] Furthermore, the first positioning recess and the first positioning protrusion are in the shape of a polygon, a circle, or an ellipse. By designing the first positioning recess and the first positioning protrusion to be in the shape of a polygon, a circle, or an ellipse, rapid self-alignment can be achieved, and the torsional resistance of the fitting structure can be enhanced, thereby improving positioning stability.

[0008] Furthermore, the shape of the second positioning recess is one of ring, multi-segment arc, or polygon. Designing the shape of the second positioning recess as ring, multi-segment arc, or polygon can ensure accurate circumferential positioning between the fixture and the printing machine table, preventing the fixture from rotating during the printing process.

[0009] Furthermore, the fixture is made of a metal material, preferably an aluminum alloy, which provides the necessary structural rigidity and strength while achieving lightweight design and facilitating the fabrication of precision structures.

[0010] Furthermore, the mating gap between the first positioning recess and the first positioning protrusion is less than 10 micrometers. Controlling the mating gap between the first positioning recess and the first positioning protrusion to within 10 micrometers greatly restricts the microscopic displacement of the PDMS sub-template within the fixture, directly improving the accuracy of pattern transfer.

[0011] Furthermore, a quick-release mechanism is installed on the fixture, making the installation and replacement of PDMS sub-templates more convenient and efficient, which helps to improve production efficiency.

[0012] Furthermore, the rigid positioning chain also includes auxiliary positioning pins or magnetic components. By adding auxiliary positioning pins or magnetic components, the connection strength and stability of the rigid positioning chain are further enhanced, making it suitable for embossing environments with high vibration or high precision requirements.

[0013] Furthermore, the first positioning recess is integrally formed on the PDMS sub-template through a molding process, ensuring the accuracy of the positioning features and simplifying the manufacturing process. The first positioning boss and the second positioning recess are integrally formed on the fixture through precision machining, ensuring the accuracy and consistency of the fixture's own positioning features.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention fundamentally eliminates the relative displacement between the interfaces of the PDMS sub-template, fixture, and printing machine worktable by constructing a series rigid positioning chain of "sub-template recess - fixture boss - fixture recess - printing machine boss". This ensures high precision, high consistency, and high uniformity of the printed pattern and provides a stable and accurate alignment reference on the template for subsequent printing. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the imprinting state of the composite structure template of this utility model.

[0016] Figure 2 This is a schematic diagram of the assembly of the fixture and the worktable of the embossing machine.

[0017] Figure 3 This is a schematic diagram of the assembly of the PDMS sub-template and fixture.

[0018] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this utility model.

[0019] Explanation of the labels in the diagram: 1. PDMS sub-template; 11. First positioning recess; 2. Fixture; 21. First positioning boss; 22. Second positioning recess. Detailed Implementation

[0020] Example: Analysis of the current state of technology: In the field of micro / nano imprinting technology, PDMS soft templates are widely used due to their excellent flexibility and release properties. However, the commonly used implementation scheme in the industry has significant structural defects: the PDMS soft template is simply laid flat inside a supporting aluminum frame, which is then placed on the frame of the imprinting machine. This structure has three key problems: first, the PDMS and the aluminum frame are fixed solely by planar contact friction; second, there is a lack of mechanical positioning between the aluminum frame and the imprinting machine frame; and third, the entire system relies solely on macroscopic alignment, without establishing a precise positioning mechanism at the microscopic scale. This simple stacked structure makes it difficult to guarantee positional stability during the imprinting process.

[0021] The process of discovering technical problems: In actual production, we observed three typical problems: systematic positional shifts in the imprinted pattern, significant differences in batch consistency, and decreased pattern uniformity in different areas of the same wafer. Process analysis revealed that the root cause of these problems lies in the mechanical instability during the imprinting process: when gas is injected into the cavity above the PDMS template (pressure increasing from 20 kPa to 50 kPa), the gas pressure causes microscopic sliding between the PDMS and the aluminum frame; during the wafer platform lifting process, the contact force further exacerbates the relative displacement between components; and due to the lack of an effective positioning structure, microscopic displacement also occurs between the aluminum frame and the imprinter frame. These micrometer-level displacements accumulate continuously during the process, ultimately manifesting as macroscopic pattern shifts and deformations.

[0022] The solution of this utility model: Based on a deep understanding of the problem mechanism, this application proposes a technical solution centered on a "multi-level self-aligning rigid positioning chain." The core innovation of this solution lies in establishing a complete positioning system from template to equipment: The first-level positioning achieves precise positioning and fixation of the sub-template by precisely engaging the positioning recess on the back of the PDMS sub-template 1 with the positioning boss on the inner ring of the fixture 2. The second-level positioning achieves precise docking between the fixture 2 and the equipment by engaging the positioning recess on the back of the outer ring of the fixture 2 with the positioning boss on the printing machine's worktable. These two levels of positioning form a series of rigid positioning chains, completely changing the traditional fixing method that relies on friction.

[0023] In practical implementation, we ensure positioning accuracy by controlling the mating gap to within 10 micrometers, enhance torsional resistance by employing polygonal or circular mating structures, guarantee structural rigidity by using metallic materials, and ensure dimensional accuracy of the positioning features through mold making and precision machining processes. This solution eliminates the possibility of relative displacement between components at the structural level, providing a reliable technical foundation for high-precision embossing.

[0024] Therefore, as Figure 1-3 As shown, the present invention adopts the following technical solution: a composite structure template suitable for PDMS micro / nano imprinting, comprising: PDMS sub-template 1, with at least one first positioning recess 11 provided on its back side; The fixture 2 is a ring-shaped structure, and its inner ring is provided with at least one first positioning protrusion 21 that matches the first positioning recess 11, for fixing the PDMS sub-template 1; The jig 2 has at least one second positioning recess 22 on the back of its outer ring; The second positioning recess 22 is used to engage with the second positioning boss on the worktable of the printing machine; A rigid positioning chain is formed by the series connection and engagement of the first positioning recess 11 and the first positioning protrusion 21, and the second positioning recess 22 and the second positioning protrusion.

[0025] In some embodiments, the first positioning recess 11 and the first positioning protrusion 21 are shaped as a polygon, a circle, or an ellipse.

[0026] In the existing technology, since simple planar contact cannot restrict circumferential rotation, this technical solution achieves self-alignment function, enhances anti-torsion ability, and improves positioning stability by designing the shapes of the first positioning recess 11 and the first positioning protrusion 21 as polygonal, circular or elliptical.

[0027] In some embodiments, the shape of the second positioning recess 22 is one of annular, multi-segment arc, or polygon.

[0028] In the prior art, there is a lack of circumferential positioning between the fixture 2 and the printing press. This technical solution ensures circumferential positioning between the fixture 2 and the printing press table by processing the second positioning recess 22 into a complete ring structure or multiple arc or polygonal shapes, such as a cone, thus preventing rotational offset.

[0029] In some embodiments, the fixture 2 is made of a metallic material, preferably an aluminum alloy.

[0030] In the existing technology, the rigidity of ordinary support frames is insufficient and they are prone to deformation. The fixture 2 in this technical solution is made of stainless steel through CNC machining, which provides excellent rigidity and strength and ensures the dimensional stability of the system. Considering that the weight of the metal fixture 2 is too large and will affect the operation, the fixture 2 is made of aluminum alloy, which achieves lightweight while ensuring rigidity and has excellent machinability.

[0031] In some embodiments, the mating gap between the first positioning recess 11 and the first positioning protrusion 21 is less than 10 micrometers, and the mating gap between the first positioning recess 11 and the first positioning protrusion 21 is controlled to be within 10 micrometers.

[0032] In the existing technology, micro-displacement between components affects accuracy. This technical solution controls the mating gap between the first positioning recess 11 and the first positioning protrusion 21, for example, 8μm, which greatly limits the micro-displacement of the PDMS sub-template 1 in the fixture 2 and directly improves the accuracy of pattern transfer.

[0033] In some embodiments, a quick-release mechanism is provided on the fixture 2.

[0034] In the existing technology, the template replacement is cumbersome and affects efficiency. This technical solution improves production efficiency by adding a quick release mechanism, such as a quick clamping mechanism, to the side of the fixture 2, thereby enabling the quick installation and replacement of the PDMS sub-template 1.

[0035] In some embodiments, the rigid positioning chain further includes auxiliary positioning pins or magnetic components, by adding auxiliary positioning pins or magnetic components.

[0036] In existing technologies, positioning may become loose under high vibration environments. This technical solution adds positioning pins at two opposite corners of the fixture, and embeds neodymium iron boron magnets at the other opposite corner. This dual positioning ensures the connection is secure under high vibration environments.

[0037] In some embodiments, the first positioning recess 11 is integrally formed on the PDMS sub-template 1 by a molding process.

[0038] In the existing technology, it is difficult to guarantee the positioning feature accuracy in the later processing. In the process of mold making of PDMS sub-template 1, the first positioning recess 11 is directly formed by using a female mold with a boss, which guarantees the positioning feature accuracy. The process is simple and compatible with the existing process.

[0039] In some embodiments, the first positioning boss 21 and the second positioning recess 22 are integrally formed on the fixture 2 by precision machining.

[0040] In the existing technology, the split positioning structure has assembly errors. In this technical solution, the first positioning boss 21 and the second positioning recess 22 on the fixture 2 are integrally machined by a five-axis machining center in one clamping, which ensures the accuracy and consistency of the positioning features of the fixture 2 itself and improves the reliability of the system.

[0041] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A composite structure template suitable for PDMS micro / nano imprinting, characterized in that, include: PDMS sub-template (1) has at least one first positioning recess (11) on its back side. The fixture (2) is a ring structure, and its inner ring is provided with at least one first positioning boss (21) that matches the first positioning recess (11) for fixing the PDMS sub-template (1). The jig (2) has at least one second positioning recess (22) on the back of its outer ring. The second positioning recess (22) is used to engage with the second positioning boss on the printing press worktable; A rigid positioning chain is formed by the series connection and engagement of the first positioning recess (11) and the first positioning protrusion (21), and the second positioning recess (22) and the second positioning protrusion.

2. The composite structure template as described in claim 1, characterized in that, The first positioning recess (11) and the first positioning protrusion (21) are in the shape of a polygon, a circle or an ellipse.

3. The composite structure template as described in claim 1, characterized in that, The shape of the second positioning recess (22) is one of ring, multi-segment arc or polygon.

4. The composite structure template as described in claim 1, characterized in that, The fixture (2) is made of metal.

5. The composite structure template as described in claim 4, characterized in that, The metal material is an aluminum alloy.

6. The composite structure template as described in claim 1, characterized in that, The mating gap between the first positioning recess (11) and the first positioning protrusion (21) is less than 10 micrometers.

7. The composite structure template as described in claim 1, characterized in that, The fixture (2) is also provided with a quick release mechanism for quickly installing and replacing the PDMS sub-template (1).

8. The composite structure template as described in claim 1, characterized in that, The rigid positioning chain also includes auxiliary positioning pins or magnetic components.

9. The composite structure template as described in claim 1, characterized in that, The first positioning recess (11) is integrally formed on the PDMS sub-template (1) through a molding process.

10. The composite structure template as described in claim 1, characterized in that, The first positioning boss (21) and the second positioning recess (22) are integrally formed on the fixture (2) by precision machining.

Images