A spectrometers based on optical interference and method of fabricating the same

Abstract

An optical interference-based spectroscopic device and a method for manufacturing the same are disclosed. The spectroscopic element comprises: a lower electrode disposed on a lower optical substrate to which a first voltage is applied; a lower acting layer disposed on the lower electrode; an upper electrode disposed on the lower part of an upper optical substrate to which the first voltage is applied; an upper acting layer disposed on the lower part of the upper electrode; and an intermediate electrode interposed between the lower acting layer and the upper acting layer to which a second voltage is applied. The lower acting layer and the upper acting layer are each polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, and are configured to adjust the air gap of the spectroscopic element by expanding and contracting by adjusting the voltage.

Description

Technology Field

[0001] The present disclosure relates to an optical interference-based spectroscopic device and a method for manufacturing the same, and more specifically, to an optical interference-based spectroscopic device having excellent resolution by stretching the air gap of the spectroscopic device by applying a low voltage and a method for manufacturing the same. Background Technology

[0002] Optical interference-based spectroscopic devices are fabricated in various ways, and among these methods, MEMS-based Fabry-Perot interferometers (FPIs) are being adopted as an excellent alternative for the miniaturization of conventional spectrometers.

[0003] Recently, FPI filters are actively used for measuring pressure, temperature, strain, and refractive index due to their low cost, minimal cross-sensitivity, and ease of fabrication. An FPI filter consists of a cavity (air gap) formed between two mirrors; the average wavelength of the filter is determined by the length of the cavity (the spacing of the air gap), while the bandwidth of the filter is determined by the reflectivity of the mirrors. When using an FPI filter, high-resolution spectra can be acquired because light waves are multiplely reflected between the two mirrors. The length of the air gap can provide a wide free spectral range (FSR) to the FPI device, ensuring a single transmission peak. The FPI filter generates a series of transmission peaks of successive perturbation orders separated by the FSR. For a wide tuning range, a low order is selected, resulting in an air gap length (air gap spacing) of only a few micrometers in the infrared region. Operating at a higher order can increase spectral resolution by reducing the full width at half maximum (FWHM), but simultaneously decreases the FSR and tuning range.

[0004] Therefore, there is a need for research on FPI spectroscopic devices that exhibit excellent resolution while consuming low power for adjusting the air gap that determines the average wavelength of the filter. The problem to be solved

[0005] The technical objective of the present disclosure is to provide an optical interference-based spectroscopic device having excellent resolution by expanding the air gap of the spectroscopic device with the application of a low voltage, and a method for manufacturing the same.

[0006] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure belongs from the description below. means of solving the problem

[0007] According to one aspect of the present disclosure, an optical interference-based spectroscopic element is provided. The spectroscopic element comprises: a lower electrode disposed on a lower optical substrate to which a first voltage is applied; a lower acting layer disposed on the lower electrode; an upper electrode disposed on the lower part of an upper optical substrate to which the first voltage is applied; an upper acting layer disposed on the lower part of the upper electrode; and an intermediate electrode interposed between the lower acting layer and the upper acting layer to which a second voltage is applied. The lower acting layer and the upper acting layer are each polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, and are configured to adjust the air gap of the spectroscopic element by expanding and contracting by adjusting the voltage.

[0008] According to another embodiment of the present disclosure, the lower acting layer and the upper acting layer may be formed to have a crystal structure of a perovskite phase.

[0009] According to another embodiment of the present disclosure, the lower acting layer and the upper acting layer may be formed of a ternary alloy of Pb, Zn, and Ti.

[0010] According to another embodiment of the present disclosure, the lower optical substrate comprises a lower transparent substrate and a lower mirror layer interposed between the lower transparent substrate and the lower acting layer, and the upper optical substrate comprises an upper transparent substrate and an upper mirror layer interposed between the upper transparent substrate and the upper acting layer, wherein the lower mirror layer and the upper mirror layer are each formed such that a low refractive index layer and a high refractive index layer are alternately stacked, and the low refractive index layer may be disposed adjacent to the lower acting layer and the upper acting layer.

[0011] According to another embodiment of the present disclosure, the lower electrode comprises a lower electrode layer and a lower attachment layer, and the upper electrode comprises an upper electrode layer and an upper attachment layer, wherein the lower attachment layer and the upper attachment layer are each disposed adjacent to the lower mirror layer and the upper mirror layer, and may be formed to comprise a metal of the same type as the low refractive index layer.

[0012] According to another embodiment of the present disclosure, the intermediate electrode comprises an intermediate electrode layer, a lower adhesive layer and an upper adhesive layer disposed on both sides of the intermediate electrode layer, and the adhesive layer can be used for adhesion between the acting layer and the intermediate electrode layer.

[0013] According to another embodiment of the present disclosure, a bonding layer disposed between the lower optical substrate and the upper optical substrate so as to be attached to the lower optical substrate and the upper optical substrate, respectively, wherein the bonding layer may be formed of a eutectic metal layer.

[0014] According to another embodiment of the present disclosure, the eutectic metal layer may be formed of a eutectic metal including silver.

[0015] According to another aspect of the present disclosure, a method for manufacturing an optical interference-based spectroscopic device is provided. The method for manufacturing the spectroscopic device comprises the steps of: forming a lower electrode and an upper electrode, each having a voltage of first polarity applied thereto on a lower optical substrate and an upper optical substrate, respectively; forming a lower acting layer and an upper acting layer on the lower electrode and the upper electrode; forming an intermediate electrode, interposed between the lower acting layer and the upper acting layer, having a voltage of second polarity applied thereto; and applying a voltage through the lower electrode, the upper electrode, and the intermediate electrode to polarize the lower acting layer and the upper acting layer, respectively. The lower acting layer and the upper acting layer are polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, respectively.

[0016] According to another embodiment of the present disclosure, the step of forming the lower acting layer and the upper acting layer may include rapid heat treatment of the lower acting layer and the upper acting layer at a temperature having a crystal structure of the perovskite phase in the lower acting layer and the upper acting layer.

[0017] According to another embodiment of the present disclosure, the lower optical substrate and the upper optical substrate are each formed to include a lower mirror layer and an upper mirror layer in which a plurality of refractive layers having at least two refractive indices are stacked, and the step of forming the bonding layer may include rapid heat treatment at a temperature interposed between the lower optical substrate and the upper optical substrate and not inducing mutual diffusion between the plurality of refractive layers.

[0018] According to another embodiment of the present disclosure, the polarizing step may include polarizing the lower acting layer and the upper acting layer, respectively, by applying a pulse voltage of a predetermined size through the lower electrode, the upper electrode, and the intermediate electrode.

[0019] According to another aspect of the present disclosure, an electronic device is provided. The electronic device comprises: an optical interference-based spectroscopic element; and a processor that controls the spectroscopic element and generates optical information based on the output of the spectroscopic element. The spectroscopic element comprises: a lower electrode disposed on a lower optical substrate to which a first voltage is applied; a lower acting layer disposed on the lower electrode; an upper electrode disposed on the lower part of an upper optical substrate to which the first voltage is applied; an upper acting layer disposed on the lower part of the upper electrode; and an intermediate electrode interposed between the lower acting layer and the upper acting layer to which a second voltage is applied. The lower acting layer and the upper acting layer are each polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, and are configured to adjust the air gap of the spectroscopic element by stretching by adjusting the voltage.

[0020] The features briefly summarized above regarding the present disclosure are merely exemplary aspects of the detailed description of the present disclosure that follows and do not limit the scope of the present disclosure. Effects of the invention

[0021] According to the present disclosure, an optical interference-based spectroscopic element having excellent resolution by stretching the air gap of the spectroscopic element with the application of a low voltage and a method for manufacturing the same can be provided.

[0022] In addition, according to the present disclosure, the lower and upper actuating layers are formed to have a crystal structure of a perovskite phase, thereby forming an actuating layer that has excellent polarization characteristics and is formed with low defects.

[0023] According to the present disclosure, when a lower and upper optical substrate comprises a lower and upper mirror layer having a plurality of refractive layers having at least two refractive indices, a silver-containing metal layer interposed between the optical substrates is rapidly heat-treated at a temperature that does not induce mutual diffusion between the plurality of refractive layers, thereby enabling smooth eutectic adhesion between the silver-containing metal layer and the adjacent refractive layer. In addition, since mutual diffusion of the metals of the refractive layers between the refractive layers does not occur, the optical properties of the refractive layers are good, and strong bonding strength and suppression of mechanical warp of the optical substrates can be achieved.

[0024] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure pertains from the description below. Brief explanation of the drawing

[0025] FIG. 1 is a schematic diagram showing an optical interference-based spectroscopic element according to one embodiment of the present disclosure. FIG. 2 is a cross-sectional view of an optical interference-based spectroscopic element according to one embodiment of the present disclosure. FIGS. 3a to 3e are drawings sequentially illustrating a method for manufacturing a spectroscopic element according to another embodiment of the present disclosure. FIG. 4 is a drawing showing a sample of a spectroscopic element fabricated according to an embodiment of the present disclosure. Figure 5 shows XRD and AFM images of the mirror layer surface of the rapidly heat-treated actuating layer. Figure 6 is a diagram showing an electron microscope image of a spectroscopic element and an EDX of an optical substrate including a mirror layer. Figure 7 is a diagram showing the polarization state of the actuating layer formed in the polarization treatment. Figure 8 is a diagram showing the repeatability of a spectroscopic element related to the response and recovery of the acting layer according to the application and non-application of voltage in terms of the stretching length of the acting layer. Figure 9 shows the results of a virtual simulation of transmitted light and transmittance according to the applied voltage, as well as the actual peak and actual transmittance of the transmitted light according to the actual applied voltage. FIG. 10 is a module diagram schematically illustrating an electronic device including a spectroscopic element according to another embodiment of the present disclosure. Specific details for implementing the invention

[0026] Hereinafter, embodiments of the present disclosure are described in detail with reference to the attached drawings so that those skilled in the art can easily implement them. However, the present disclosure may be embodied in various different forms and is not limited to the embodiments described herein.

[0027] In describing the embodiments of the present disclosure, if it is determined that a detailed description of known configurations or functions could obscure the essence of the present disclosure, such detailed description is omitted. Additionally, parts of the drawings unrelated to the description of the present disclosure have been omitted, and similar parts are denoted by similar reference numerals.

[0028] In the present disclosure, when a component is described as being "connected," "combined," or "joined" with another component, this may include not only a direct connection but also an indirect connection in which another component exists in between. Furthermore, when a component is described as "comprising" or "having" another component, this means that, unless specifically stated otherwise, it does not exclude the other component but may include additional components.

[0029] In the present disclosure, terms such as first, second, etc. are used solely for the purpose of distinguishing one component from another component and do not limit the order or importance of the components unless specifically stated otherwise. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and likewise, a second component in one embodiment may be referred to as a first component in another embodiment.

[0030] In addition, expressions of positional relationships used in the specification, such as top, bottom, left, right, etc., are provided for convenience of explanation, and if the drawings illustrated in this specification are viewed in reverse, the positional relationships described in the specification may be interpreted in the opposite way.

[0031] In the present disclosure, the components described in various embodiments do not necessarily mean essential components, and some may be optional components. Accordingly, embodiments consisting of a subset of the components described in one embodiment are also included within the scope of the present disclosure. Furthermore, embodiments including other components in addition to the components described in various embodiments are also included within the scope of the present disclosure.

[0032] In the present disclosure, each of the phrases such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, C or combination thereof” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof.

[0033] The advantages and features of the present disclosure and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments presented below but can be implemented in various different forms, and these embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention.

[0034] Hereinafter, an optical interference-based spectroscopic element according to an embodiment of the present disclosure will be described with reference to FIGS. 1 and FIGS. 2. FIGS. 1 is a schematic diagram showing an optical interference-based spectroscopic element according to an embodiment of the present disclosure. FIGS. 2 is a cross-sectional view showing an optical interference-based spectroscopic element according to an embodiment of the present disclosure.

[0035] The optical interference-based spectroscopic element (100) may be a spectroscopic filter using a MEMS-based Fabry-Perot interferometer (FPI). The spectroscopic element (100) may be fabricated to selectively filter light of, for example, a specific wavelength or a target wavelength.

[0036] Specifically, the spectroscopic element (100) may include a lower optical substrate (110), a lower electrode (120), a lower acting layer (130), an upper optical substrate (140), an upper electrode (150), and an upper acting layer (160). The lower electrode (120) and the lower acting layer (130) may be sequentially stacked on the lower optical substrate (110), and the upper electrode (150) and the upper acting layer (160) may be sequentially stacked on the lower part of the upper optical substrate (140). In addition, the spectroscopic element (100) may include an intermediate electrode (170) interposed between the lower acting layer (130) and the upper acting layer (160), and a bonding layer (not shown in FIG. 1; 190 in FIG. 2) disposed between the lower optical substrate (110) and the upper optical substrate (140). In addition, the cavity (180) is provided between the lower optical substrate (110) and the upper optical substrate (140) and can be formed as a hollow space existing in the central region of the patterned members, namely the lower electrode (120), the lower acting layer (130), the intermediate electrode (170), the upper acting layer (160), and the upper electrode (150). The cavity (180) can function as an air gap in which the size of the cavity (180) is adjusted as the lower acting layer (130) and the upper acting layer (160) expand and contract according to the application of voltage.

[0037] The lower optical substrate (110) may include a lower transparent substrate (112) and a lower mirror layer (114) disposed on top thereof. The lower transparent substrate (112) may be, for example, a quartz substrate.

[0038] The lower mirror layer (114) can be formed such that a low refractive index layer (114a) and a high refractive index layer (114b) are alternately stacked. The low refractive index layer (114a) is a layer having a lower refractive index than the high refractive index layer (114b), and can be formed, for example, as a transparent oxide film having a lower refractive index than the high refractive index layer (114b). More specifically, the low refractive index layer (114a) can be formed as a titanium oxide film (TiO2). Additionally, the low refractive index layer (114a) can be positioned, for example, adjacent to the lower electrode (120) located below the lower acting layer (130) before the high refractive index layer (114b). This contributes to the adhesion with the lower electrode (120) and can effectively transmit light of the target wavelength. As another example, even if the high refractive index layer (114b) is positioned adjacent to the lower electrode (120), light of the target wavelength can be effectively transmitted. The high refractive index layer (114b) is formed as a transparent oxide film similar to the low refractive index layer (114a), and can be formed, for example, as a silicon oxide film (SiO2).

[0039] The lower mirror layer (114) may be composed of alternating refractive / dielectric layers of silicon oxide and titanium oxide having a thickness of λ / 4n. Here, n is the refractive index of the dielectric material constituting the mirror layer, and λ may be the wavelength of the light to be transmitted. The thickness described above may also be applied to the upper mirror layer (144). Accordingly, the lower mirror layer (114), composed of alternating high refractive index layers (114b) and low refractive index layers (114a), can efficiently transmit light of a specific wavelength by providing high reflectivity and low loss.

[0040] FIG. 2 illustrates a lower mirror layer (114) formed as a five-layer stack in which a low refractive index layer (114a) and a high refractive index layer (114b) are alternately stacked. Specifically, FIG. 2 illustrates that the low refractive index layer (114a) and the high refractive index layer (114b) alternate from the lower electrode (120), and the low refractive index layer (114a) is arranged on the lower side of the lower transparent substrate (112). The thickness of each of the five refractive index layers (114a, 114b) can be determined by considering the light of the target wavelength, reflectance, light loss, etc. When the low refractive index layer (114a) and the high refractive index layer (114b) are formed from titanium oxide and silicon oxide, respectively, the thickness of each layer can be formed sequentially from the lower electrode (120) as a low refractive index layer of 85 nm, a high refractive index layer of 146 nm, a low refractive index layer of 85 nm, a high refractive index layer of 85 nm, and a low refractive index layer of 85 nm. The thickness values ​​described above are merely examples, and each layer can be formed such that, in accordance with the relationship between the thickness values ​​shown above, each low refractive index layer (114a) has the same thickness, and the high refractive index layer (114b) closer to the lower electrode (120) is larger than the low refractive index layer (114a) and smaller than the high refractive index layer (114b) closer to the lower optical substrate (110). In addition, the high refractive index layer (114b) near the lower optical substrate (110) can be formed with substantially the same thickness as the low refractive index layer (114a).

[0041] For example, when the target wavelength is set to 850 nm, the lower mirror layer (114) and upper mirror layer (144) of the high-refractive-index layer (114b) and low-refractive-index layer to which the above-described thickness value is applied can exhibit excellent optical properties by showing a high peak at approximately 870 nm (approaching the wavelength of 850 nm) so that the cavity (180) is also maintained at 850 nm (~m.λ / 2, where m=2). Mirror layers (114, 144) configured in the order of high-refractive-index layer / low-refractive-index layer consisting of a 5-layer stack may be the optimal configuration for achieving the target wavelength of 850 nm.

[0042] Next, the lower electrode (120) may be an electrode to which a first voltage is applied in an operation for expanding the cavity (180). The first voltage may be, for example, a negative voltage and may be applied based on a target wavelength. The lower electrode (120) may include a lower electrode layer (122) and a lower attachment layer (124). The lower electrode layer (122) may be formed of, for example, platinum (Pt) or gold (Au). The lower attachment layer (124) may include a metal of the same type as the low refractive index layer (114a) to contribute to smooth adhesion between the lower mirror layer (114) and the lower electrode layer (122). For example, if the low refractive index layer (114a) is a titanium oxide film, the lower attachment layer (124) may contain titanium. Additionally, the lower attachment layer (124) may be formed to contain a component of the same type as the metal contained in the lower acting layer (130). If the lower acting layer (130) is formed of a ternary alloy of Pb, Zn and Ti, the lower attachment layer (124) may contain titanium.

[0043] Next, the lower acting layer (130) expands or contracts by voltage applied to the lower electrode (120) and the intermediate electrode (170) or by voltage off, so that together with the upper acting layer (160), the air gap of the cavity (180) can be adjusted.

[0044] For expansion according to the applied voltage, the lower acting layer (130) may be pre-polarized such that the polarity facing the lower electrode (120) and the polarity facing the intermediate electrode (170) are different. For example, the polarity facing the lower electrode (120) may be positive, and the polarity facing the intermediate electrode (170) may be negative. Due to the pre-polarization, the lower acting layer (130) can be expanded to match the target wavelength even with the application of a low voltage.

[0045] The lower actuating layer (130) can be formed to have a crystal structure of a perovskite phase. As a result, the lower actuating layer (130) has good polarization alignment during the fabrication process and / or in the finished spectroscopic device, and the defects of the actuating layer (130, 160) can be very few. To have a perovskite phase, the lower actuating layer (130) can be formed from a ternary alloy of Pb, Zn, and Ti.

[0046] Meanwhile, members substantially identical to the layers described above formed on the lower transparent substrate (112) may be formed on the lower transparent substrate (142). Since the members on the lower side, including the upper transparent substrate (142), differ only in terms of arrangement structure from the lower transparent substrate (112) and the layers on the upper side, and are substantially identical in terms of composition, characteristics, and function, the members on the lower side of the upper transparent substrate (142) will be described with a focus on aspects not described in the layers on the lower transparent substrate (112).

[0047] The upper mirror layer (144) is positioned below the upper transparent substrate (142) and can be formed such that a low refractive index layer (144a) and a high refractive index layer (144b) are alternately stacked. For example, the low refractive index layer (144a) can be positioned adjacent to the upper electrode (150) located above the upper acting layer (160) before the high refractive index layer (144b). This contributes to the adhesion with the upper electrode (150) and can effectively transmit light of the target wavelength. As another example, even if the high refractive index layer (144b) is positioned adjacent to the upper electrode (150), light of the target wavelength can be effectively transmitted. The high refractive index layer (144b) is formed as a transparent oxide film similar to the low refractive index layer (144a), and can be produced, for example, as a silicon oxide film (SiO2).

[0048] The thickness of the upper mirror layer (144), the number of stacks of the low-refractive-index layer (144a) and the high-refractive-index layer (144b) of the upper mirror layer (144), and the thickness of each are substantially the same as described in the lower mirror layer (114), and the resulting effect is also substantially the same as described in the lower mirror layer (114).

[0049] The upper electrode (150) may be an electrode to which a first voltage is applied in an operation for expanding the cavity (180). The first voltage may be, for example, a negative voltage and may be applied based on a target wavelength. The upper electrode (150) may include an upper electrode layer (152) and an upper attachment layer (154). The materials of the upper electrode layer (152) and the upper attachment layer (154) are as described in the lower electrode layer (122) and the lower attachment layer (124).

[0050] The upper acting layer (160) can expand or contract by voltage applied to the upper electrode (150) and the middle electrode (170) or voltage off, and together with the lower acting layer (130), can adjust the air gap of the cavity (180).

[0051] For expansion according to the applied voltage, the upper acting layer (160) may be pre-polarized such that the polarity facing the upper electrode (150) and the polarity facing the intermediate electrode (170) are different. For example, the polarity facing the upper electrode (150) may be positive, and the polarity facing the intermediate electrode (170) may be negative. Due to the pre-polarization, the upper acting layer (160) can be expanded to match the target wavelength even with the application of a low voltage.

[0052] The upper actuating layer (160) may be formed to have a crystal structure of a perovskite phase. The material of the upper actuating layer (160) may be the same as or different from the lower actuating layer (130). If the coefficients of thermal expansion of the upper and lower actuating layers are excessively different, the stress (or shear stress) between the upper and lower actuating layers may differ due to heat treatment during the manufacturing process or the application of voltage to the device, thereby degrading the quality of the device. Accordingly, the upper actuating layer (160) and the lower actuating layer (130) may be formed of the same material or of different materials having a difference in coefficients of thermal expansion within a predetermined range. If the upper acting layer (160) is made of the same material as the lower acting layer (130), the upper acting layer (160) may be formed of a ternary alloy of Pb, Zn, and Ti, and the composition ratio of the alloy may be the same as or different from that of the lower acting layer (130) depending on process conditions and device performance.

[0053] Next, the intermediate electrode (170) may be an electrode interposed between the lower acting layer (130) and the upper acting layer (160) to which a second voltage is applied. The second voltage may be, for example, a voltage of 0V or higher. The intermediate electrode (170) may include an intermediate electrode layer (172), a lower adhesive layer (174) and an upper adhesive layer (176) disposed on both sides of the intermediate electrode layer (172). The intermediate electrode layer (172) may contain, for example, silver. The lower adhesive layer (174) may be used for adhesion between the lower acting layer (130) and the intermediate electrode layer (172), and the upper adhesive layer (176) may be used for adhesion between the upper acting layer (160) and the intermediate electrode layer (172). The lower and upper adhesive layers (174, 176) may be formed to contain a component of the same type as the metal contained in the lower and upper actuating layers (130, 160). If the lower and upper actuating layers (130, 160) are formed of a ternary alloy of Pb, Zn, and Ti, the lower and upper adhesive layers (174, 176) may contain titanium.

[0054] Next, the bonding layer (190) is disposed between the lower optical substrate (110) and the upper optical substrate (140), as illustrated in FIG. 2, and can be attached to the lower optical substrate (110) and the upper optical substrate, respectively. The bonding layer can be formed into a eutectic metal layer by using Rapid Thermal Annealing (RTA) within a predetermined temperature range. The eutectic metal layer may contain a metal having excellent eutectic bonding properties with the low refractive index layers (114a, 144a) of the lower mirror layer (114) and the upper mirror layer (144). If the low refractive index layers (114a, 144a) are titanium oxide films, the bonding layer (190) may be formed, for example, of silver having excellent diffusivity to the low refractive index layers (114, 144a).

[0055] According to the present disclosure, a plurality of polarized actuating layers, namely a lower actuating layer (130) and an upper actuating layer (160) that are polarized in a predetermined shape, adjust the air gap of the cavity (180), thereby causing the air gap of the spectroscopic element (100) to expand and contract upon the application of a low voltage, so that the spectroscopic element (100) can have excellent resolution when filtering light of a target wavelength.

[0056] Hereinafter, a method for manufacturing an optical interference-based spectroscopic element according to another embodiment of the present disclosure will be described. FIGS. 3a to 3e are drawings sequentially illustrating a method for manufacturing a spectroscopic element according to another embodiment of the present disclosure. In the following description, details identical to those described above are omitted and replaced with the aforementioned details.

[0057] First, referring to FIG. 3a, a lower mirror layer (114) and an upper mirror layer (144) can be formed on a lower transparent substrate (112) and an upper transparent substrate (142), respectively, which are composed of a quartz wafer.

[0058] The lower mirror layer (114) and the upper mirror layer (144) may be formed as a combination film in which low-refractive-index layers (114a, 144a) and high-refractive-index layers (114b, 144b) are alternately stacked. The low-refractive-index layers (114a, 144a) and high-refractive-index layers (114b, 144b) may be formed from titanium oxide and silicon oxide, respectively. In order to maintain surface uniformity and form the exact thickness of each layer, the low-refractive-index layers (114a, 144a) and high-refractive-index layers (114b, 144b) may be formed, for example, using an electron beam evaporation system at room temperature.

[0059] FIG. 3a illustrates a lower mirror layer (114) and an upper mirror layer (144) formed by a five-layer stack in which low-refractive-index layers (114a, 144a) and high-refractive-index layers (114b, 144b) are alternately stacked. The top layer of each stack, the layer adjacent to the lower electrode (120) and the upper electrode (150), may be formed of a low-refractive-index layer (114a).

[0060] The thickness of each of the five refractive index layers (114a, 114b, 144a, 144b) can be determined by considering light of the target wavelength, reflectance, light loss, etc. When the low refractive index layer (114a, 144a) and the high refractive index layer (114b, 144b) are formed from a titanium oxide film and a silicon oxide film, respectively, the thickness of each layer can be formed sequentially from the lower electrode (120) and the upper electrode (170) as a low refractive index layer of 85 nm, a high refractive index layer of 146 nm, a low refractive index layer of 85 nm, a high refractive index layer of 85 nm, and a low refractive index layer of 85 nm. The thickness values ​​described above are merely examples, and each layer may be formed such that, in accordance with the relationship between the thickness values ​​shown in the examples, each low-refractive-index layer (114a, 144a) has the same thickness, and the high-refractive-index layer (114b, 144b) near the lower electrode (120) and the upper electrode (170) is larger than the low-refractive-index layer (114a, 144a) and has a smaller thickness than the high-refractive-index layer (114b, 144b) near the lower optical substrate (110) and the lower optical substrate (140). Additionally, the high-refractive-index layer (114b, 144b) near the lower optical substrate (110) and the upper optical substrate (140) may be formed with substantially the same thickness as the low-refractive-index layer (114a, 144a).

[0061] Referring to FIG. 3b, a lower electrode (120) and an upper electrode (150) can be formed on the lower mirror layer (114) and the upper mirror layer (144), respectively.

[0062] The lower electrode (120) may be formed to include a lower electrode layer (122) and a lower attachment layer (124). The upper electrode (150) may include an upper electrode layer (152) and an upper attachment layer (154). The lower electrode layer (122) and the upper electrode layer (152) may be formed of, for example, platinum (Pt) or gold (Au). The lower attachment layer (124) and the upper attachment layer (154) may include a metal of the same type as the low refractive index layer (114a, 144a) to contribute to smooth adhesion between the mirror layer (114, 144) and the electrode layer (122, 152). For example, if the low refractive index layer (114a, 144a) is a titanium oxide film, the lower attachment layer (124) and the upper attachment layer (154) may contain titanium. Additionally, the lower attachment layer (124) and the upper attachment layer (154) may be formed to contain components of the same type as the metal contained in the lower acting layer (130) and the upper acting layer (160). When the lower acting layer (130) and the upper acting layer (160) are formed of a ternary alloy of Pb, Zn, and Ti, the lower attachment layer (124) and the upper attachment layer (154) may contain titanium.

[0063] When the lower attachment layer (124), upper attachment layer (154), lower electrode layer (122), and upper electrode layer (152) are formed from the material described above, a positive photoresist is spin-coated on the lower mirror layer (114) and the upper mirror layer (144), and a patterning process such as UV lithography is used to create a preliminary pattern for forming the lower electrode (120) and the upper electrode (150). Subsequently, a titanium film and a platinum film are sequentially deposited by an electron beam evaporation system, and a lift process is performed to form the lower electrode (120) composed of the lower attachment layer (124) and the lower electrode layer (122), and the upper electrode (150) composed of the upper attachment layer (154) and the upper electrode layer (152). For example, titanium films and platinum films are formed with thicknesses of 30 nm and 100 nm, respectively, but are not limited thereto and can be formed with various thicknesses depending on device characteristics and process conditions.

[0064] Referring to FIG. 3c, a lower acting layer (130) and an upper acting layer (160) can be formed on the lower electrode (120) and the upper electrode (150).

[0065] The lower acting layer (130) and the upper acting layer (160) may be formed of the same or different materials, and the present disclosure exemplifies that they are formed of the same material. In the case of the same, the lower acting layer (130) and the upper acting layer (160) may be formed of a ternary alloy of Pb, Zn, and Ti.

[0066] Specifically, a photoresist pattern corresponding to the pattern of the lower acting layer (130) and the upper acting layer (160) can be formed for PZT deposition by using a photolithography process on the lower electrode (120) and the upper electrode (150). Subsequently, a PZT film is deposited on the lower electrode (120) and the upper electrode (150) by RF sputtering at room temperature, and the lower acting layer (130) and the upper acting layer (160) can be formed by performing a lift process.

[0067] Next, rapid thermal annealing (RTA; 210) may be performed on the lower acting layer (130) and the upper acting layer (160) at a temperature having a crystal structure on a perovskite phase. The lower acting layer (130) and the upper acting layer (160) may be rapidly annealed for 150 seconds at 450 to 600 degrees in an oxygen atmosphere, for example, to crystallize the structure. The lower acting layer (130) and the upper acting layer (160), which are composed of PZT films, may be crystallized by rapid thermal annealing (210) in an oxygen atmosphere at different temperatures for 150 seconds to avoid interdiffusion between the refractive index layers of the mirror layers (114, 144). Through rapid heat treatment at 600 degrees, the lower acting layer (130) and the upper acting layer (160) are PZT (PbZr 0.54 Ti 0.46O3 It is formed as ) and can be formed into a perovskite polycrystalline structure without evidence of secondary phases.

[0068] Referring to FIG. 3d, intermediate electrodes (170) can be formed on the lower acting layer (130) and the upper acting layer (160), respectively.

[0069] The intermediate electrode (170) may be formed to have a lower adhesive layer (174) and an intermediate electrode layer (172) sequentially disposed on a lower actuating layer (130), and an upper adhesive layer (176) and an intermediate electrode layer (172) sequentially disposed on an upper actuating layer (160).

[0070] The intermediate electrode layer (172) may contain, for example, silver. The lower and upper adhesive layers (174, 176) may be formed to contain a component of the same type as the metal contained in the lower and upper acting layers (130, 160) to facilitate adhesion between the acting layer and the intermediate electrode layer (172). If the lower and upper acting layers (130, 160) are formed of a ternary alloy of Pb, Zn, and Ti, the lower and upper adhesive layers (174, 176) may contain titanium.

[0071] In FIG. 3d, the intermediate electrode (170) is exemplified as being formed on the lower acting layer (130) and the upper acting layer (160), respectively, and the following description will focus on the example in FIG. 3d. In a different example, the intermediate electrode layer (172) of the intermediate electrode (170) may be formed on only one of the lower acting layer (130) and the upper acting layer (160), and the lower adhesive layer (174) and the upper adhesive layer (176) may be formed on the lower acting layer (130) and the upper acting layer (160), respectively.

[0072] When the intermediate electrode layer (172) and the adhesive layer (172, 176) each contain silver and titanium, an intermediate electrode (170) including the intermediate electrode layer (172), the lower adhesive layer (174), and the upper adhesive layer (176) can be formed by using a lift process applied to the lower electrode (120) and the upper electrode (150).

[0073] Referring to FIG. 3e, a bonding layer (190) can be formed between the lower optical substrate (110) and the upper optical substrate (140) so as to be attached to the lower optical substrate (110) and the upper optical substrate (140), respectively.

[0074] The bonding layer (190) may be formed as a eutectic metal layer. The eutectic metal layer may contain a metal having excellent eutectic bonding properties with the low refractive index layers (114a, 144a) of the lower mirror layer (114) and the upper mirror layer (144). If the low refractive index layers (114a, 144a) are titanium oxide films, the bonding layer (190) may be formed, for example, of silver having excellent diffusivity to the low refractive index layers (114, 144a).

[0075] When the bonding layer (190) is formed as a metal layer containing silver, the bonding layer (190) can be created by using a rapid heat treatment (220) in a temperature range that does not induce mutual diffusion between a plurality of refractive layers (114a, 114b, 144a, 144b) constituting the lower and upper mirror layers (114, 144). For example, the bonding layer (190) can be formed by a rapid heat treatment (220) for 15 seconds at a temperature of 800 to 900 degrees. More specifically, when the rapid heat treatment is performed at a temperature of 900 degrees, a very good (or narrow) full width at half maximum (FWHM) appears at the target transmission peak of 850 nm, and the heat treatment is performed at a high temperature for a short period of time, so that changes in the intermetallic diffusion and air gap of the refractive layers may not be induced.

[0076] Accordingly, an intermediate electrode layer (172) on the lower acting layer (130) and the upper acting layer (160) can be bonded to complete an intermediate electrode (170) interposed between these layers. Additionally, by attaching the lower optical substrate (110) and the upper optical substrate (140) to each other, a cavity (180) surrounded by the inner circumference of the lower electrode (120), the upper electrode (150), and the intermediate electrode (170) can be formed.

[0077] After the lower optical substrate (110) and the upper optical substrate (140) are bonded together by a bonding layer (190), a pulse voltage of a predetermined size is applied through the lower electrode (120), the upper electrode (150), and the intermediate electrode (170) to polarize the lower acting layer (130) and the upper acting layer (160), respectively.

[0078] The lower acting layer (130) and the upper acting layer (160) may be polarized such that the polarity facing the lower electrode (120) and the upper electrode (150) and the polarity facing the intermediate electrode are different, respectively. As illustrated in FIG. 2, in the lower and upper acting layers (130, 160), the polarity facing the lower electrode (120) may be positive, and the polarity facing the intermediate electrode (170) may be negative. The pulse voltage applied in the polarization may be, for example, 0V to the intermediate electrode (170) and -10 to -20V to the lower and upper electrodes (120, 150). The pulse voltage is generated by a separate device for applying a predetermined voltage to the spectroscopic element (100), and the device may be configured to include, for example, a pulse generator that generates a pulse wave having a specific voltage and an amplifier that amplifies the pulse wave output from the generator to a desired voltage. The reason for polarizing the lower acting layer (130) and the upper acting layer (160) into pulse waves is to prevent the constituent atoms of the acting layer from being continuously used by the electric field when a DC voltage is applied for a long time, thereby preventing a non-elastic condition from being induced, and also to control the duty cycle.

[0079] In the present disclosure, polarization is described as being performed after the bonding layer (190) is formed, but before the formation of the bonding layer (190), polarization similar to the process described above can be performed between the lower electrode (120) and the intermediate electrode (170) and between the upper electrode (150) and the intermediate electrode (170) while the lower optical substrate (110) and the upper optical substrate (140) are separated.

[0080] Hereinafter, with reference to FIGS. 5 to 10, the analysis results and characteristics derived through various experiments on the spectroscopic sensor according to the embodiment of the present disclosure will be described.

[0081] For the above experiment, the spectroscopic sensor exemplified in FIG. 2 was fabricated according to the process and the specifications of each layer described in FIG. 3a to 3e. The spectroscopic sensor accordingly was fabricated as the spectroscopic element sample shown in FIG. 4. FIG. 4 is a drawing showing a spectroscopic element sample fabricated according to an embodiment of the present disclosure. In the spectroscopic element sample of FIG. 4, the bonding layer interposed between the lower and upper optical substrates may be formed as a dot pattern spaced apart from the lower electrode, the upper electrode, and the intermediate electrode, respectively.

[0082] Figure 5 shows XRD and AFM images of the mirror layer surface of the rapidly heat-treated actuating layer.

[0083] Lower and upper actuating layers were formed with an 850 nm air gap between the lower and upper optical substrates having mirror layers. To avoid interdiffusion between the refractive index layers of the mirror layer at different temperatures for 150 seconds, the lower and upper actuating layers formed from PZT were crystallized in an oxygen atmosphere via rapid thermal treatment. To confirm the successful crystal formation of PZT, the XRD patterns of PZT with and without rapid thermal treatment (annealing) were recorded as shown in FIG. 5(a). Before annealing, peaks corresponding to the perovskite phase were not observed in the XRD pattern. After annealing, peaks (101) corresponding to the perovskite phase were clearly observed, indicating that a PZT-based film was successfully formed. Specifically, FIG. 5(a) shows PZT (PbZr) annealed at 400°C with RTA. 0.54 Ti 0.46O3 Figure 5(b) shows the XRD pattern of the mirror layer. Figure 5(b) shows that after heat treatment, the surface roughness of the low refractive index layer formed of titanium in the mirror layer is flat within the desired range. Figure 5(b) indicates that the surface roughness of the low refractive index layer is improved by the eutectic bonding process applied to the bonding layer, namely the rapid heat treatment process mentioned in Figure 3e.

[0084] Figure 6 is a diagram showing an electron microscope image of a spectroscopic element and an EDX of an optical substrate including a mirror layer.

[0085] By applying the rapid thermal processing of FIG. 3c to the lower and upper actuating layers and the rapid thermal processing of FIG. 3e to the bonding layer, as shown in FIG. 6(a), an air gap capable of achieving a target wavelength of 850 nm is formed well without a change in the air gap, and at the same time, as shown in FIG. 6(b), no diffusion of metal, i.e. titanium, between the refractive index layers of the mirror layer is observed. In FIG. 6(b), titanium appears in the form of dots as a metal constituting the low refractive index layer.

[0086] Metal interdiffusion between the mirror layer and the refractive index layer is a critical issue during the bonding process of the lower and upper optical substrates via the bonding layer. If exposed to high temperatures for a long time in an RTA chamber, interdiffusion occurs between the refractive index layers, which can degrade device performance. To increase bonding strength and the performance of the fabricated device, it is desirable to set the exposure time of the device to high temperatures in the RTA to a short duration, as in this embodiment. Consequently, silver diffuses smoothly into the titanium oxide film, which is the low refractive index layer, allowing for the formation of a good eutectic alloy between them and resulting in strong bonding strength. Furthermore, the mirror layers bonded by the bonding layer can maintain their bonding characteristics even when lateral shear forces are applied. Additionally, when rapid thermal processing is performed at a temperature of 800 to 900 degrees, a very good (or narrow) full width at half maximum (FWHM) appears at the target transmission peak of 850 nm. It can be confirmed that mechanical warping in the mirror layer is suppressed due to the bonding layer fabricated as described above.

[0087] Figure 7 is a diagram showing the polarization state of the actuating layer formed in the polarization treatment. Figure 7 shows the polarization state according to the diameter sizes of the cavity in the spectroscopic element, 1, 2, and 4 mm.

[0088] When an acting layer having each diameter is subjected to the rapid heat treatment described in FIG. 3, each acting layer is formed to have a crystal structure on a perovskite phase, and by applying a pulse voltage for polarization described in FIG. 3e, each acting layer can be polarized into the shape of a curve shown in FIG. 7. After that, even if the application of the pulse voltage is stopped, it can be confirmed that the polarization of each acting layer is maintained as shown in FIG. 7.

[0089] Figure 8 is a diagram showing the repeatability of a spectroscopic element related to the response and recovery of the acting layer according to the application and non-application of voltage in terms of the stretching length of the acting layer.

[0090] When pulse voltages switching between 0V and -10V are repeatedly applied to the upper and lower electrodes of an actuating layer formed of PZT, it can be confirmed that the expansion and contraction of the actuating layer occur immediately upon voltage application, and that the length and response time according to the expansion and contraction are constant. In addition, it can be seen that during expansion, an air gap corresponding to a target wavelength of 850 nm, that is, an expansion length of the actuating layer corresponding to this air gap, is realized in FIG. 8.

[0091] Figure 9 shows the results of a virtual simulation of transmitted light and transmittance according to the applied voltage, as well as the actual peak and actual transmittance of the transmitted light according to the actual applied voltage.

[0092] Figure 9(a) is a virtual simulation result for a spectroscopic element with the conditions and specifications of Figure 3 applied, showing the transmitted light and transmittance according to the applied voltage. In the simulation results, it can be observed that as the pulsed applied voltage increases, the air gap also increases, and as the air gap increases, the transmitted light shifts to a longer wavelength.

[0093] Figure 9(b) shows the results for a spectroscopic device actually fabricated under the conditions and specifications of Figure 3, and indicates the actual peak and actual transmittance of the transmitted light according to the applied pulse voltage. The magnitudes of the applied pulse voltages are 10, 15, and 20 V. As the pulse voltage increases, the air gap varies to become larger, and it shows that the transmitted light appearing as the actual peak shifts well to a longer wavelength, identical to the virtual simulation. It can be seen that when 20 V is applied, the peak shifts by 5 nm compared to 0 V, and through this, it can be confirmed that the spectroscopic device according to the present embodiment effectively filters the transmitted light of the desired wavelength by adjusting the applied voltage.

[0094] Hereinafter, FIG. 10 describes an electronic device to which a spectroscopic sensor according to an embodiment of the present disclosure is applied. FIG. 10 is a module diagram schematically showing an electronic device including a spectroscopic element according to another embodiment of the present disclosure.

[0095] The electronic device (300) may be a device capable of communicating with other devices via wired or wireless means by employing a spectroscopic sensor (310) according to the present disclosure. For example, the electronic device (300) may be a spectroscopic sensor device, an analysis device based on detection data of the spectroscopic sensor, a smart mobile device equipped with a spectroscopic sensor and implementing various functions, etc.

[0096] That is, the electronic device (300) filters light of a target wavelength, e.g., 850 nm, using a spectroscopic sensor (310), and may perform a predetermined processing based on the filtered light or transmit the results of the processing to another device, and is not limited to the embodiments described above. As an example, for the operation described above, the electronic device (300) may include a spectroscopic sensor (310) according to the present disclosure, a transceiver (320) that controls transmission and reception with another external device, a display (330) that visually displays the light or signal of the target wavelength output from the spectroscopic sensor (310) and the results related to processing thereof, a memory (340) that processes and stores the signal output from the spectroscopic sensor (310), and a processor (350) that controls all of the elements described above. That is, the electronic device (300) may include a configuration necessary for communicating with another device or may display the results of mutual data processing. In addition, as an example, the device may include other configurations in addition to the configurations described above. That is, the device is merely a configuration including the device described above to perform communication with another device, and is limited thereto, and may be a device that operates based on the above.

[0097] The exemplary methods of the present disclosure described above are expressed as a series of operations for clarity of explanation, but this is not intended to limit the order in which the steps are performed, and if necessary, each step may be performed simultaneously or in a different order. To implement the method according to the present disclosure, additional steps may be included in addition to the steps exemplified, steps excluding some steps and including the remaining steps, or steps excluding some steps and including additional steps.

[0098] The various embodiments of the present disclosure are not intended to list all possible combinations but to describe representative aspects of the present disclosure, and the matters described in the various embodiments may be applied independently or in combination of two or more.

[0099] The scope of the present disclosure includes software or machine-executable instructions (e.g., operating system, application, firmware, program, etc.) that enable an operation according to a method of various embodiments to be executed on a device or computer, and a non-transitory computer-readable medium on which such software or instructions, etc. are stored and executable on a device or computer.

Claims

Claim 1 In an optical interference-based spectroscopic device, a lower electrode disposed on a lower optical substrate to which a first voltage is applied; a lower acting layer disposed on the lower electrode; an upper electrode disposed on the lower part of an upper optical substrate to which the first voltage is applied; and an upper acting layer disposed on the lower part of the upper electrode. and includes an intermediate electrode interposed between the lower acting layer and the upper acting layer to which a second voltage is applied, wherein the lower acting layer and the upper acting layer are each polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, and are configured to adjust the air gap of the spectroscopic element by expanding and contracting by adjusting the voltage, wherein the lower acting layer, the intermediate electrode, and the upper acting layer are configured as a circle including an inner circumference and an outer circumference of a predetermined size, and the intermediate electrode includes an intermediate electrode layer, a lower adhesive layer and an upper adhesive layer disposed on both sides of the intermediate electrode layer, wherein the adhesive layer is used for attachment between the upper acting layer and the intermediate electrode layer, and the lower acting layer, the intermediate electrode, and the upper acting layer are continuously coupled in the height direction, and the air gap is formed by the coupled lower acting layer, the intermediate electrode, and A spectroscopic element formed by a hollow space existing in a central region formed by the inner circumference of the upper actuating layer, wherein the lower optical substrate includes a lower transparent substrate and a lower mirror layer interposed between the lower transparent substrate and the lower electrode, and the upper optical substrate includes an upper transparent substrate and an upper mirror layer interposed between the upper transparent substrate and the upper electrode, and wherein the lower mirror layer and the upper mirror layer are each formed such that a low refractive index layer and a high refractive index layer are alternately stacked. Claim 2 A spectroscopic element according to claim 1, wherein the lower acting layer and the upper acting layer are formed to have a crystal structure of a perovskite phase. Claim 3 A spectroscopic element according to claim 1, wherein the lower acting layer and the upper acting layer are formed of a ternary alloy of Pb, Zn, and Ti. Claim 4 A spectroscopic element according to claim 1, wherein the low refractive index layer is disposed adjacent to the lower acting layer and the upper acting layer. Claim 5 A spectroscopic element according to claim 4, wherein the lower electrode comprises a lower electrode layer and a lower attachment layer, the upper electrode comprises an upper electrode layer and an upper attachment layer, the lower attachment layer and the upper attachment layer are each disposed adjacent to the lower mirror layer and the upper mirror layer, and are formed to include a metal of the same type as the low refractive index layer. Claim 6 delete Claim 7 A spectroscopic element according to claim 1, comprising a bonding layer disposed between the lower optical substrate and the upper optical substrate so as to be attached to the lower optical substrate and the upper optical substrate, respectively, wherein the bonding layer is formed of a eutectic metal layer. Claim 8 In claim 7, the spectroscopic element, wherein the eutectic metal layer is formed of a eutectic metal including silver. Claim 9 A method for manufacturing an optical interference-based spectroscopic device comprises: forming a lower electrode and an upper electrode, each having a voltage of first polarity applied thereto, on a lower optical substrate and an upper optical substrate, respectively; forming a lower acting layer and an upper acting layer on the lower electrode and the upper electrode; and forming an intermediate electrode to which a voltage of second polarity is applied thereto, interposed between the lower acting layer and the upper acting layer. The method includes the step of applying a voltage through the lower electrode, the upper electrode, and the intermediate electrode to polarize the lower acting layer and the upper acting layer, respectively, wherein the lower acting layer and the upper acting layer are polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, and the lower acting layer, the intermediate electrode, and the upper acting layer are configured as a circle including an inner circumference and an outer circumference of a predetermined size, and the intermediate electrode includes an intermediate electrode layer, a lower adhesive layer and an upper adhesive layer disposed on both sides of the intermediate electrode layer, and the adhesive layer is used for attachment between the upper acting layer and the intermediate electrode layer, and the lower acting layer, the intermediate electrode, and the upper acting layer are continuously coupled in the height direction, and the air gap is a hollow existing in the central region formed by the inner circumference of the coupled lower acting layer, the intermediate electrode, and the upper acting layer. A method for manufacturing a spectroscopic element, wherein the lower optical substrate is formed as a space, the lower optical substrate comprises a lower transparent substrate and a lower mirror layer interposed between the lower transparent substrate and the lower electrode, the upper optical substrate comprises an upper transparent substrate and an upper mirror layer interposed between the upper transparent substrate and the upper electrode, and the lower mirror layer and the upper mirror layer are each formed such that a low refractive index layer and a high refractive index layer are alternately stacked. Claim 10 A method for manufacturing a spectroscopic element according to claim 9, wherein the lower acting layer and the upper acting layer are formed to have a crystal structure on a perovskite phase. Claim 11 A method for manufacturing a spectroscopic device according to claim 10, wherein the step of forming the lower acting layer and the upper acting layer comprises rapidly heat treating the lower acting layer and the upper acting layer at a temperature having a crystal structure on the perovskite phase in the lower acting layer and the upper acting layer. Claim 12 A method for manufacturing a spectroscopic element according to claim 9, wherein the lower acting layer and the upper acting layer are formed of a ternary alloy of Pb, Zn, and Ti. Claim 13 A method for manufacturing a spectroscopic element according to claim 9, wherein the low refractive index layer is formed adjacent to the lower acting layer and the upper acting layer. Claim 14 A method for manufacturing a spectroscopic element according to claim 13, wherein the lower electrode is formed to include a lower electrode layer and a lower attachment layer, the upper electrode is formed to include an upper electrode layer and an upper attachment layer, the lower attachment layer and the upper attachment layer are each disposed adjacent to the lower mirror layer and the upper mirror layer, and are formed to include a metal of the same type as the low refractive index layer. Claim 15 delete Claim 16 A method for manufacturing a spectroscopic element according to claim 9, further comprising the step of forming a bonding layer between the lower optical substrate and the upper optical substrate so as to be attached to the lower optical substrate and the upper optical substrate, respectively, wherein the bonding layer is formed of a eutectic metal layer. Claim 17 A method for manufacturing a spectroscopic element according to claim 16, wherein the eutectic metal layer is formed from a eutectic metal including silver. Claim 18 A method for manufacturing a spectroscopic element according to claim 17, wherein the lower optical substrate and the upper optical substrate are each formed to include a lower mirror layer and an upper mirror layer in which a plurality of refractive layers having at least two refractive indices are stacked, and the step of forming the bonding layer comprises rapid heat treatment at a temperature interposed between the lower optical substrate and the upper optical substrate and not inducing mutual diffusion between the plurality of refractive layers. Claim 19 A method for manufacturing a spectroscopic element according to claim 9, wherein the polarizing step comprises polarizing the lower acting layer and the upper acting layer, respectively, by applying a pulse voltage of a predetermined size through the lower electrode, the upper electrode and the intermediate electrode. Claim 20 An optical interference-based spectroscopic element; and a processor that controls the spectroscopic element and generates optical information based on the output of the spectroscopic element, wherein the spectroscopic element comprises: a lower electrode disposed on a lower optical substrate to which a first voltage is applied; a lower acting layer disposed on the lower electrode; an upper electrode disposed on the lower part of an upper optical substrate to which the first voltage is applied; and an upper acting layer disposed on the lower part of the upper electrode. and includes an intermediate electrode interposed between the lower acting layer and the upper acting layer to which a second voltage is applied, wherein the lower acting layer and the upper acting layer are each polarized such that the polarity toward the lower electrode and the upper electrode and the polarity toward the intermediate electrode are different, and are configured to adjust the air gap of the spectroscopic element by expanding and contracting by adjusting the voltage, wherein the lower acting layer, the intermediate electrode, and the upper acting layer are configured as a circular shape including an inner circumference and an outer circumference of a predetermined size, and the intermediate electrode includes an intermediate electrode layer, a lower adhesive layer and an upper adhesive layer disposed on both sides of the intermediate electrode layer, wherein the adhesive layer is used for attachment between the upper acting layer and the intermediate electrode layer, wherein the lower acting layer, the intermediate electrode, and the acting layer are continuously coupled in the height direction, and the air gap is formed between the coupled lower acting layer, the intermediate electrode, and the upper An electronic device formed by a hollow space existing in a central region formed by the inner circumference of an actuating layer, wherein the lower optical substrate includes a lower transparent substrate and a lower mirror layer interposed between the lower transparent substrate and the lower electrode, and the upper optical substrate includes an upper transparent substrate and an upper mirror layer interposed between the upper transparent substrate and the upper electrode, and wherein the lower mirror layer and the upper mirror layer are each formed such that a low refractive index layer and a high refractive index layer are alternately stacked.

Images