Filter manufacturing method, filter and spectral detection device
Patent Information
- Application Number
- CN202611066193.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-17
- Publication Date
- 2026-10-30
Smart Images
Figure CN123010329A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of micro-nano optoelectronic device technology, and particularly relates to a filter fabrication method, filter array and spectral detection device. Background Technology
[0002] Currently, miniature spectrometers based on computational reconstruction algorithms are gaining widespread attention in fields such as the Internet of Things, smart portable devices, and medical diagnostics due to their small size. The spectrometer's spectral detection device integrates filters on top of the detection substrate. The filters typically include a first reflective layer, a resonant filter layer, and a second reflective layer stacked sequentially. The resonant filter layer comprises multiple resonant filter units with different thicknesses, enabling the detection array to detect different wavelengths of light.
[0003] In related technologies, when fabricating the resonant filter layer of a filter, a movable mask is placed above the first reflective layer. Then, by using physical vapor deposition, and controlling the position of the movable mask above the first reflective layer and the duration for which part of the first reflective layer is exposed to the evaporation source, resonant filter units of different thicknesses can be formed on the first reflective layer, thereby forming the resonant filter layer.
[0004] However, the filter production efficiency in related technologies is low, the filter consistency is poor, and it is not conducive to improving the resolution of spectral detection devices.
[0005] In view of this, embodiments of this application provide a filter manufacturing method, a filter array, and a spectrometer to solve the technical problems of low filter production efficiency, poor filter consistency, and difficulty in improving the resolution of spectral detection devices in related technologies.
[0006] This application provides a method for manufacturing a filter, including: Provide a first reflective layer; A filter medium layer is formed on the first reflective layer; An imprinted adhesive layer is formed on the side of the filter medium layer opposite to the first reflective layer; An embossing template is provided, and an embossing groove is provided on one side of the embossing template. The embossing groove includes multiple embossing sub-grooves, and the depth of the multiple embossing sub-grooves is set to correspond to the thickness of multiple preset resonant filter units. The embossing groove of the embossing template is fitted and embossed onto the embossing adhesive layer, so that at least part of the embossing adhesive layer fills the embossing sub-groove to form a plurality of embossing adhesive units. The imprinting adhesive unit and the filter medium layer are etched to form multiple resonant filter units corresponding to the multiple imprinting adhesive units in the filter medium layer; A second reflective layer is formed, which covers a plurality of the resonant filter units.
[0007] Compared with the physical vapor deposition equipment and movable mask used in related technologies to fabricate multiple resonant filter units, the filter fabrication method of this application does not require a movable mask and does not require multiple vapor depositions. It has a short production time, simplifies the production process, improves the production efficiency of the filter, and thus reduces the production cost of the filter.
[0008] Furthermore, the filter fabrication method of this application embodiment does not require multiple depositions of resonant filter units of different thicknesses using a physical vapor deposition (PVD) device, thus avoiding the influence of inherent problems of the PVD device on multiple resonant filter units and improving the consistency of filters produced in the same batch.
[0009] Furthermore, the filter fabrication method in this application does not employ a physical hard mask, which avoids edge shadowing effects and mechanical alignment errors during physical vapor deposition. This helps ensure the verticality of the vertical edges of the resonant filter unit and reduces crosstalk between adjacent resonant filter units, allowing the size of a single resonant filter unit to be further miniaturized, which is beneficial for improving the resolution of the spectral detection device.
[0010] In some possible embodiments, the etching rate of the imprinting adhesive unit and the etching rate of the filter medium layer are the same, and the thickness of the imprinting adhesive unit and the corresponding resonant filter unit are the same.
[0011] In some possible embodiments, the etching rates of the imprinting adhesive unit and the filter medium layer are the same, and the thicknesses of the imprinting adhesive unit and the corresponding resonant filter unit are proportional.
[0012] In some possible embodiments, the etching rate of the imprinting adhesive unit is Rr, the etching rate of the filter medium layer is Rd, and the etching selectivity is S=Rd / Rr; the thickness difference of the plurality of imprinting adhesive units is Δh, and the thickness difference of the plurality of resonant filter units is ΔH=S·Δh.
[0013] In some possible embodiments, a nanoimprint resist is coated on the side of the filter medium layer opposite to the first reflective layer, the amount of the nanoimprint resist corresponding to the thickness of the plurality of preset resonant filter units.
[0014] In some possible embodiments, the nanoimprint resist is coated onto the side of the filter medium layer opposite to the first reflective layer by spin coating or inkjet drop coating.
[0015] In some possible embodiments, the embossing groove is stepped onto the embossing adhesive layer in multiple steps.
[0016] In some possible embodiments, the inner surface of the embossing groove is treated with an anti-sticking agent.
[0017] This application also provides a filter, which is manufactured using the filter manufacturing method described in any of the preceding claims.
[0018] The filters in this application embodiment are manufactured using the filter manufacturing method described in any of the preceding claims. The filters have high production efficiency, good consistency, and are beneficial for improving the resolution of spectral detection devices. Further details regarding this aspect will not be elaborated upon in this application embodiment.
[0019] This application also provides a spectral detection device, including a detection substrate and a filter as described above, wherein the filter is disposed on the detection substrate.
[0020] Since the spectral detection device of the present application embodiment includes the above-mentioned filter, the spectral detection device also has the advantages of the above-mentioned filter, which will not be repeated here.
[0021] In some possible embodiments, the detector substrate includes a detector array having a plurality of detector pixels; the filter includes a plurality of resonant filter units, which are disposed in a one-to-one correspondence with the plurality of detector pixels, wherein at least two of the resonant filter units have different thicknesses. Attached Figure Description
[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. It is obvious that the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0023] Figure 1 This is a cross-sectional structural diagram of the spectral detection device according to an embodiment of this application; Figure 2 This is a schematic flowchart of a filter manufacturing method according to an embodiment of this application; Figure 3 This is a cross-sectional structural diagram of the filter fabrication method according to an embodiment of the present application, when an imprinting adhesive layer is formed on the filter medium layer. Figure 4 This is a cross-sectional structural diagram of the filter manufacturing method according to an embodiment of the present application, when the imprinting template is imprinted onto the imprinting adhesive layer. Figure 5 This is a cross-sectional structural diagram of the filter manufacturing method according to an embodiment of the present application, during the demolding of the imprint template. Figure 6This is a schematic cross-sectional view of the etching process of the imprinting adhesive unit and the filter medium layer in the filter fabrication method of this application embodiment. Figure 7 This is a cross-sectional structural diagram of the second reflective layer formed in the filter fabrication method of this application embodiment.
[0024] Explanation of reference numerals in the attached figures: 100 - Probe substrate; 110 - Detector array; 111 - Detector pixel; 120 - Circuit layer; 200-filter; 210 - First reflective layer; 220 - Resonant filter layer; 221 - Resonant filter unit; 230 - Second reflective layer; 231 - Reflection unit; 300-Filter Media Layer; 400 - Imprinting adhesive layer; 410 - Imprinting unit; 500 - Imprinting template; 510 - Imprint groove; 511 - Imprint sub-groove. Detailed Implementation
[0025] In related technologies, physical vapor deposition (PVD) equipment and a movable mask are generally used to fabricate filters. Specifically, a substrate with a first reflective layer is first provided in the PVD equipment. A movable mask is then placed above the first reflective layer. By controlling the position of the movable mask above the first reflective layer and the duration for which the first reflective layer is exposed to the evaporation source within the PVD equipment, resonant filter units of different thicknesses can be formed on the first reflective layer to form a resonant filter layer. A second reflective layer is then formed above the resonant filter layer.
[0026] However, the filter manufacturing methods in related technologies require repeated movement of the mask and multiple vapor deposition processes during the fabrication of the resonant filter unit. This results in long production times, complex manufacturing processes, reduced filter production efficiency, and higher filter production costs.
[0027] Furthermore, due to the inherent problem of thickness drift at the chamber edge during the deposition of film in physical vapor deposition equipment, when producing multiple filters in the same chamber, the thickness of the same resonant filter unit differs between the filter located at the center of the chamber and the filter located at the edge of the chamber, resulting in poor consistency of filters produced in the same batch.
[0028] Furthermore, the movable mask is a physical hard mask, with a tiny gap between it and the first reflective layer. During physical vapor deposition, edge shading effects and mechanical alignment errors result in a large vertical edge slope for the resonant filter unit, leading to severe crosstalk between adjacent resonant filter units. To reduce or even avoid this problem, the size of a single resonant filter unit needs to be sufficiently large. This prevents further miniaturization of the size of a single resonant filter unit, which is detrimental to improving the resolution of the spectral detection device.
[0029] To address the aforementioned technical problems, this application provides a filter fabrication method, a filter, and a spectral detection device. The filter fabrication method of this application involves sequentially forming a filter dielectric layer and an imprinting adhesive layer on a first reflective layer. First, multiple imprinting adhesive units corresponding to preset resonant filter units are formed on the imprinting adhesive layer using an imprinting method. Then, the multiple imprinting adhesive units and the filter dielectric layer are etched to form multiple resonant filter units in the filter dielectric layer, each corresponding one-to-one with the multiple imprinting adhesive units. The filter fabrication method of this application uses imprinting and etching to form multiple resonant filter units.
[0030] Compared with the physical vapor deposition equipment and movable mask used in related technologies to fabricate multiple resonant filter units, the filter fabrication method of this application does not require a movable mask and does not require multiple vapor depositions. It has a short production time, simplifies the production process, improves the production efficiency of the filter, and thus reduces the production cost of the filter.
[0031] Furthermore, the filter fabrication method of this application embodiment does not require multiple depositions of resonant filter units of different thicknesses using a physical vapor deposition (PVD) device, thus avoiding the influence of inherent problems of the PVD device on multiple resonant filter units and improving the consistency of filters produced in the same batch.
[0032] Furthermore, the filter fabrication method in this application does not employ a physical hard mask, which avoids edge shadowing effects and mechanical alignment errors during physical vapor deposition. This helps ensure the verticality of the vertical edges of the resonant filter unit and reduces crosstalk between adjacent resonant filter units, allowing the size of a single resonant filter unit to be further miniaturized, which is beneficial for improving the resolution of the spectral detection device.
[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0034] This application provides a spectrometer, which may include a spectral detection component for detecting spectra.
[0035] like Figure 1 As shown, the spectral detection device may include a detection substrate 100 and a filter 200, with the filter 200 disposed on the detection substrate 100. The filter 200 is used to filter light of a specific wavelength. The detection substrate 100 is used for photoelectric conversion. Light emitted by an object is filtered by the filter 200 and then enters the detection substrate 100, thereby achieving spectral detection. Compared with grating-type and filter-type spectrometers in related technologies, this embodiment of the application disposes of the filter 200 on the detection substrate 100, that is, the filter 200 and the detection substrate 100 are integrated, which is beneficial to reducing the size of the spectral detection device, thereby reducing the size of the spectrometer.
[0036] The detector substrate 100 may include a detector array 110 for converting optical information into electrical information. The detector substrate 100 may have multiple detector pixels 111.
[0037] In some possible implementations of the embodiments of this application, the detector array 110 can be a complementary metal-oxide-semiconductor (CMOS) detector array 110.
[0038] The CMOS detector array 110 has advantages such as low power consumption, high speed, strong anti-interference capability, high integration, good compatibility, low driving requirements, and good signal isolation. Furthermore, the CMOS detector array 110 has a mature manufacturing process and good device stability, which helps reduce the production cost of spectral detection devices and improve their performance stability.
[0039] In other possible implementations of this application, the detector array 110 may also be a charge-coupled device (CCD) detector array 110. The CCD detector array 110 has advantages such as high resolution and high noise immunity, which is beneficial to improving the spectral detection accuracy of the spectral detection device.
[0040] It is understood that the detector array 110 can also be other detector arrays 110 with photoelectric conversion capability, which will not be described in detail in this application embodiment.
[0041] The detection substrate 100 may further include a circuit layer 120 for processing the converted electrical signal. Exemplarily, the circuit layer 120 may be disposed below the detection array 110. The circuit layer 120 can perform operations such as readout and compensation on the converted electrical signal, which will not be elaborated further in this embodiment.
[0042] refer to Figure 1 The filter 200 may include a first reflective layer 210, a resonant filter layer 220, and a second reflective layer 230. The first reflective layer 210 may be disposed on the side of the detector substrate 100 facing away from the circuit layer 120. The first reflective layer 210, the resonant filter layer 220, and the second reflective layer 230 may be stacked sequentially. Based on the Fabry-Perot (FP) principle, light of a specific wavelength can be amplified, enters the resonant filter layer 220 from the second reflective layer 230, exits from the first reflective layer 210, and then enters the detector array 110, thereby realizing the detection of a specific spectrum.
[0043] For example, the first reflective layer 210 can be a first metal layer. For instance, the material of the first metal layer can be silver (Ag) or aluminum (Al). It is understood that the material of the first metal layer can also be other metal materials with reflective properties, which will not be elaborated further in this embodiment.
[0044] The first reflective layer 210 can also be a distributed Bragg reflector (DBR).
[0045] like Figure 1 As shown, the resonant filter layer 220 may include multiple resonant filter units 221, which may be correspondingly arranged with multiple pixels of the detector array 110. At least two of the resonant filter units 221 may have different thicknesses. Resonant filter units 221 with different thicknesses can filter light of different specific wavelengths, allowing light of different wavelengths to enter the detector pixel 111, thereby enabling the detection of different spectral bands.
[0046] It should be noted that some of the resonant filter units 221 may have the same thickness, and resonant filter units with the same thickness can filter light of the same specific wavelength. Alternatively, the thicknesses of the multiple resonant filter units 221 may all be different, and the multiple resonant filter units 221 can filter light of different specific wavelengths.
[0047] Multiple resonant filter units 221 can be configured corresponding to multiple detector pixels 111 of the detector array 110. In some possible implementations of the embodiments of this application, the same resonant filter unit 221 can be configured corresponding to at least two detector pixels 111.
[0048] In some other possible implementations of the embodiments of this application, at least two filter resonant units can be configured to correspond to the same detector pixel 111.
[0049] In other possible implementations of the embodiments of this application, such as Figure 1 As shown, multiple resonant filter units 221 and multiple detector pixels 111 can be configured in a one-to-one correspondence. That is, each resonant filter unit 221 corresponds to one detector pixel 111. This configuration can make full use of the detector array 110, which is beneficial to improving the resolution of the spectral detection device.
[0050] For example, the second reflective layer 230 can be a second metal layer. For instance, the material of the second metal layer can be silver (Ag) or aluminum (Al). It is understood that the material of the second metal layer can also be other metal materials with reflective properties, which will not be elaborated further in this embodiment.
[0051] The second reflective layer 230 can also be a DBR.
[0052] For example, the second reflective layer 230 may include a plurality of reflective units 231. The plurality of reflective units 231 may be arranged one-to-one with a plurality of resonant filter units 221. Each reflective unit 231 may cover the top surface of its corresponding resonant filter unit 221, as well as a portion of the side surface of the resonant unit adjacent to that reflective unit 231. This arrangement helps prevent light from escaping between two adjacent reflective units 231, thereby helping to avoid light leakage from the filter 200.
[0053] This application also provides a method for manufacturing a filter 200. Any filter 200 in this application embodiment can be obtained by this filter 200 manufacturing method.
[0054] like Figure 2 As shown, the method for manufacturing the filter 200 according to an embodiment of this application may include the following steps: S100, provides the first reflective layer.
[0055] For example, a substrate can be provided first, and then the first reflective layer 210 can be formed on the substrate. The substrate can provide support for the first reflective layer 210, which helps to ensure the morphology of the first reflective layer 210.
[0056] For example, the substrate can be a detector substrate 100, and the first reflective layer 210 can be directly formed on the detector substrate 100. With this configuration, the filter 200 can be directly integrated onto the detector substrate 100 without the need for additional bonding processes, which helps to save process steps and thus improves the production efficiency of spectral detection devices.
[0057] For example, the first reflective layer 210 can be fabricated using physical vapor deposition.
[0058] S200, A filter medium layer is formed on the first reflective layer.
[0059] refer to Figure 3 A filter medium layer 300 is formed above the first reflective layer 210. The filter medium layer 300 is used to form a filter layer in subsequent steps. Exemplarily, the filter medium layer 300 can be fabricated using physical vapor deposition.
[0060] S300, An imprinted adhesive layer is formed on the side of the filter medium layer facing away from the first reflective layer.
[0061] like Figure 3 As shown, an imprinted adhesive layer 400 is formed on the side of the filter medium layer 300 facing away from the first reflective layer 210, that is, above the filter medium layer 300.
[0062] For example, the material of the imprinting adhesive layer 400 can be a nanoimprinting resist.
[0063] In some possible implementations of this application, the amount of nanoimprint resist can correspond to the thickness of multiple preset resonant filter units 221. The thickness of the preset resonant filter unit 221 refers to the desired thickness of the resonant filter unit 221, i.e., the design value of the resonant filter unit 221. When the thickness of the preset resonant filter unit 221 is large, the amount of nanoimprint resist is large; when the thickness of the preset resonant filter unit 221 is small, the amount of nanoimprint resist is small. This arrangement facilitates full utilization of the nanoimprint resist, reduces material costs, and is beneficial for the molding of the resonant filter unit 221.
[0064] For example, a nanoimprint resist can be coated onto the side of the filter medium layer 300 facing away from the first reflective layer 210 by spin coating or inkjet drop coating. Spin coating or inkjet drop coating can form an imprint resist layer 400 with controllable thickness and good uniformity on the surface of the filter medium layer 300, providing a suitable material basis for subsequent imprinting processes and facilitating the acquisition of an ideal resonant filter unit 221.
[0065] S400. An imprinting template is provided. An imprinting groove is provided on one side of the imprinting template. The imprinting groove includes multiple imprinting sub-grooves. The depth of the multiple imprinting sub-grooves corresponds to the thickness of multiple preset resonant filter units.
[0066] like Figure 4 As shown, an impression template 500 for impressioning can be provided. An impression groove 510 can be provided on one side of the impression template 500.
[0067] The imprint groove 510 may include a plurality of imprint sub-grooves 511. The depth of the plurality of imprint sub-grooves 511 may be set to correspond to the thickness of the plurality of preset resonant filter units 221. For example, the plurality of imprint sub-grooves 511 may correspond one-to-one with the plurality of preset resonant filter units 221, and the depth of each imprint sub-grooves 511 may be the same as the thickness of its corresponding preset resonant filter unit 221.
[0068] For example, the material of the imprint template 500 can be quartz or silicon wafer.
[0069] For example, an imprint groove 510 can be formed on one side of the imprint template 500 using electron beam lithography or grayscale lithography combined with dry etching. This configuration helps to ensure the dimensional accuracy of the imprint groove 510, thereby helping to ensure the dimensional accuracy of the fabricated resonant filter unit 221.
[0070] S500, The impression groove of the impression template is fitted and impression is pressed onto the impression adhesive layer, so that at least part of the impression adhesive layer fills the impression sub-groove to form a plurality of impression adhesive units.
[0071] refer to Figure 4 The imprinting groove 510 of the imprinting template can be fitted onto the imprinting adhesive layer 400. For example, the imprinting template can be aligned with the detector pixels 111 of the detector array 110 under vacuum or a controlled atmosphere before the imprinting template is fitted onto the imprinting adhesive layer 400. This arrangement allows the detector pixels 111 to position the imprinting template, thereby improving the positional accuracy of the imprinting template and facilitating the improvement of the positional accuracy of the subsequently fabricated resonant filter unit 221.
[0072] Then, uniform pressure can be applied to the impression template so that at least a portion of the impression adhesive layer 400 can be filled into the impression sub-groove 511 to form a plurality of impression adhesive units 410.
[0073] In some possible implementations of this application, the imprinting groove 510 of the imprinting template can be applied and imprinted onto the imprinting adhesive layer 400 in a single step to form all the imprinting adhesive units 410. This arrangement can improve the efficiency of forming the imprinting adhesive units 410, which is beneficial to improving the production efficiency of the filter 200.
[0074] In some other possible implementations of this application, the imprinting groove 510 of the imprinting template can be stepped onto the imprinting adhesive layer 400 in multiple steps. That is, when the imprinting groove 510 of the imprinting template is stepped onto the imprinting adhesive layer 400 in a single step, a partial imprinting adhesive unit 410 can be formed. By stepping onto the imprinting groove 510 in multiple steps and imprinting it onto the imprinting adhesive layer 400, all imprinting adhesive units 410 can be formed. This arrangement is beneficial for processing large-area filters 200 while ensuring the high precision of the imprinting adhesive units 410.
[0075] In some other possible implementations of this application, the detector substrate 100 can be flexible. When the imprinting groove 510 of the imprinting template is fitted and imprinted onto the imprinting adhesive layer 400, a roll-to-roll imprinting process can be used. The spectral detection device can be provided in continuous roll form, which helps to reduce the manufacturing cost of the spectral detection device.
[0076] For example, the inner surface of the impression tank 510 can be treated with an anti-adhesion coating. This configuration helps prevent the impression adhesive layer 400 from adhering to the inner surface of the impression tank 510 during the impression process, thereby helping to ensure the morphology of the impression adhesive unit 410.
[0077] like Figure 5 As shown, after the impression groove 510 of the impression template is fitted onto the impression adhesive layer 400 and the impression is pressed, the impression adhesive layer 400 can be cured, and the impression template can be demolded. For example, ultraviolet light or a heat field can be applied to cause the impression adhesive layer 400 to undergo a polymerization and cross-linking reaction, thereby curing the impression adhesive layer 400 and forming a plurality of morphologically stable impression adhesive units 410. Then, the impression template is removed from the plurality of impression adhesive units 410, completing the demolding process.
[0078] S600, Etch the imprinting adhesive unit and the filter medium layer so that the filter medium layer forms multiple resonant filter units corresponding to multiple imprinting adhesive units.
[0079] refer to Figure 6 The imprinting adhesive unit 410 and the filter medium layer 300 are etched. During the etching process, the imprinting adhesive unit 410 can be used as a grayscale mask. The thickness of the imprinting adhesive unit 410 corresponds to different masking times, so that different areas of the filter medium layer 300 are etched for different times, thereby forming multiple resonant filter units 221 corresponding to multiple imprinting adhesive units 410 in the filter medium layer 300, thus forming a resonant filter layer 220.
[0080] It should be noted that the etching rates of the imprinting adhesive unit 410 and the filter medium layer 300 can be the same or different. When the etching rates of the imprinting adhesive unit 410 and the filter medium layer 300 are the same, the thicknesses of the imprinting adhesive unit 410 and its corresponding resonant filter unit 221 can be the same. When the etching rates of the imprinting adhesive unit 410 and the filter medium layer 300 are different, the thicknesses of the imprinting adhesive unit 410 and its corresponding resonant filter unit 221 can be set proportionally.
[0081] For example, the etching rate of the imprinting adhesive unit 410 can be Rr, the etching rate of the filter medium layer 300 can be Rd, and the etching selectivity ratio between the two can be S=Rd / Rr. The height difference of the multiple imprinting adhesive units 410 can be Δh, and the thickness difference of the multiple resonant filter units 221 can be ΔH=S·Δh.
[0082] S700, forming a second reflective layer, the second reflective layer covers multiple resonant filter units.
[0083] refer to Figure 7 After the filter layer is formed, a second reflective layer 230 is formed. The second reflective layer 230 can cover multiple resonant filter units 221 to form an FP cavity with the multiple resonant units and the first reflective layer 210.
[0084] For example, the second reflective layer 230 can be fabricated using physical vapor deposition.
[0085] Compared with the physical vapor deposition equipment and movable mask used in related technologies to fabricate multiple resonant filter units 221, the filter 200 fabrication method of this application embodiment does not require a movable mask and does not require multiple vapor depositions, resulting in shorter production time, simplified production process, improved production efficiency of filter 200, and thus reduced production cost of filter 200.
[0086] Furthermore, the filter 200 manufacturing method of this application embodiment does not use physical vapor deposition equipment, which can avoid the influence of inherent problems of physical vapor deposition equipment on the filter 200, thereby improving the consistency of the filter 200 produced in the same batch.
[0087] Furthermore, the filter 200 fabrication method in this application embodiment does not employ a physical hard mask, which can avoid edge shadowing effects and mechanical alignment errors during physical vapor deposition. This is beneficial for ensuring the verticality of the vertical edge of the resonant filter unit 221 and for reducing crosstalk between adjacent resonant filter units 221. This allows the size of a single resonant filter unit 221 to be further miniaturized, which is beneficial for improving the resolution of the spectral detection device.
[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A method for manufacturing a filter, characterized in that, include: Provide a first reflective layer; A filter medium layer is formed on the first reflective layer; An imprinted adhesive layer is formed on the side of the filter medium layer opposite to the first reflective layer; An embossing template is provided, and an embossing groove is provided on one side of the embossing template. The embossing groove includes multiple embossing sub-grooves, and the depth of the multiple embossing sub-grooves is set to correspond to the thickness of multiple preset resonant filter units. The embossing groove of the embossing template is fitted and embossed onto the embossing adhesive layer, so that at least part of the embossing adhesive layer fills the embossing sub-groove to form a plurality of embossing adhesive units. The imprinting adhesive unit and the filter medium layer are etched to form multiple resonant filter units corresponding to the multiple imprinting adhesive units in the filter medium layer; A second reflective layer is formed, which covers a plurality of the resonant filter units.
2. The filter manufacturing method according to claim 1, characterized in that, The etching rate of the imprinting adhesive unit and the etching rate of the filter medium layer are the same, and the thickness of the imprinting adhesive unit and the corresponding resonant filter unit are the same.
3. The filter manufacturing method according to claim 1, characterized in that, The etching rates of the imprinting adhesive unit and the filter medium layer are the same, and the thicknesses of the imprinting adhesive unit and the corresponding resonant filter unit are set in proportion.
4. The filter manufacturing method according to claim 3, characterized in that, The etching rate of the imprinting adhesive unit is Rr, the etching rate of the filter medium layer is Rd, and the etching selectivity is S=Rd / Rr; the thickness difference of the plurality of imprinting adhesive units is Δh, and the thickness difference of the plurality of resonant filter units is ΔH=S·Δh.
5. The method for manufacturing a filter according to claim 1, characterized in that, A nanoimprint resist is coated on the side of the filter medium layer facing away from the first reflective layer, and the amount of the nanoimprint resist corresponds to the thickness of the plurality of preset resonant filter units.
6. The method for manufacturing a filter according to claim 5, characterized in that, The nanoimprint resist is coated onto the side of the filter medium layer opposite to the first reflective layer by spin coating or inkjet drop coating.
7. The method for manufacturing a filter according to claim 1, characterized in that, The embossing groove is stepped and pressed onto the embossing adhesive layer in multiple steps; Alternatively, the inner surface of the embossing groove may be treated with an anti-sticking agent.
8. A filter, characterized in that, It is prepared by the filter manufacturing method as described in any one of claims 1-7.
9. A spectral detection device, characterized in that, It includes a detector substrate and a filter as described in claim 8, the filter being disposed on the detector substrate.
10. The spectral detection device according to claim 9, characterized in that, The detection substrate includes a detection array, which has multiple detection pixels; The filter includes multiple resonant filter units, and each of the multiple resonant filter units is configured in a one-to-one correspondence with a multiple of the detection pixels, wherein at least two of the resonant filter units have different thicknesses.