Device and manufacturing method thereof

Abstract

To provide a manufacturing method of an element which enables improvement of operation characteristics.SOLUTION: A manufacturing method of an element 1 includes: a step in which an alignment mark 3 formed of a non-transparent material is formed on a front surface of a substrate 2 formed of glass; a step in which a transparent film is formed on a rear surface of the substrate 2; a step in which positioning is performed from the rear surface of the substrate 2 by using the alignment mark 3 to form a resist pattern on the transparent film; a step in which the resist pattern is used as a mask to etch the transparent film and form an alignment mark 4; a step in which a protection film formed of a non-transparent material is formed on the alignment mark 4; a step in which positioning is performed from the rear surface of the substrate 2 by using the alignment mark 4 and the protection film on the alignment mark 4 to form a resist pattern on the protection film; and a step in which the resist pattern is used as a mask to etch the protection film.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a device and a method for manufacturing the same. [Background technology]

[0002] MEMS elements manufactured using MEMS (Micro Electro Mechanical Systems) technology, such as MEMS microphones, are known. MEMS elements using glass substrates are also known. MEMS elements are manufactured using a photolithography process.

[0003] In one example of a MEMS element, a MEMS structure is placed on the front surface of a glass substrate, and a glass hole is formed on the back surface of the glass substrate. When manufacturing such a MEMS element, the positional relationship between the MEMS structure and the glass hole is very important because it affects the operating characteristics of the MEMS element.

[0004] To form the glass holes, a mask for forming the glass holes must be formed on the back surface of the glass substrate in accordance with the position of the MEMS structure. A non-transparent film that can withstand glass etching is used as the mask for forming the glass holes.

[0005] However, when patterning a non-transparent film, if the non-transparent film is formed on the back surface of the glass substrate, the entire surface is shielded from light, making it impossible to detect the alignment marks on the front surface, and in this case, it becomes impossible to align the patterns on the front surface and the back surface. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2019-201263 A Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention provides an element capable of improving operating characteristics and a method for manufacturing the same. [Means for solving the problem]

[0008] According to a first aspect of the present invention, there is provided a method for manufacturing an element, comprising the steps of: forming a first alignment mark made of a non-transparent material on a front surface of a substrate made of glass; forming a transparent film on a back surface of the substrate; aligning from the back surface of the substrate using the first alignment mark and forming a first resist pattern on the transparent film; etching the transparent film using the first resist pattern as a mask to form a second alignment mark; forming a first protective film made of a non-transparent material on the second alignment mark; aligning from the back surface of the substrate using the second alignment mark and the first protective film on the second alignment mark and forming a second resist pattern on the first protective film; and etching the first protective film using the second resist pattern as a mask.

[0009] According to a second aspect of the present invention, there is provided a method for manufacturing an element according to the first aspect, further comprising, after the step of etching the first protective film, a step of forming a structure on the front surface of the substrate, and a step of etching the substrate using the first protective film as a mask.

[0010] According to a third aspect of the present invention, there is provided a method for manufacturing an element relating to the second aspect, further comprising a step of forming a second protective film made of a non-transparent material on the front surface of the substrate simultaneously with the first alignment mark, and the structure is formed on the second protective film.

[0011] According to a fourth aspect of the present invention, there is provided a method for manufacturing an element according to the second or third aspect, wherein the structure is a MEMS structure.

[0012] According to a fifth aspect of the present invention, there is provided a method for manufacturing an element according to any one of the first to fourth aspects, wherein the second alignment mark is arranged at a position different from that of the first alignment mark in a plan view.

[0013] According to a sixth aspect of the present invention, there is provided a method for producing an element according to any one of the first to fifth aspects, wherein the transparent film is made of ITO (indium tin oxide).

[0014] According to a seventh aspect of the present invention, there is provided a method for manufacturing an element according to any one of the first to sixth aspects, wherein the first protective film is made of chromium (Cr) or an alloy containing chromium (Cr).

[0015] According to an eighth aspect of the present invention, there is provided an element comprising a substrate having a front surface and a back surface, an opening extending from the front surface to the back surface and made of glass, a structure provided on the front surface so as to cover the opening, a first alignment mark provided on the front surface of the substrate and made of a non-transparent material, and a second alignment mark provided on the back surface of the substrate and made of a transparent material, wherein, in a planar view, the second alignment mark is positioned at a different position from the first alignment mark.

[0016] According to a ninth aspect of the present invention, there is provided the element according to the eighth aspect, further comprising a first protective film formed on the second alignment mark and made of a non-transparent material.

[0017] According to a tenth aspect of the present invention, there is provided the element according to the eighth or ninth aspect, further comprising a second protective film made of a non-transparent material and provided between the substrate and the structure.

[0018] According to an eleventh aspect of the present invention, there is provided a device according to any one of the eighth to tenth aspects, wherein the structure is a MEMS structure.

[0019] According to a twelfth aspect of the present invention, there is provided the element according to any one of the eighth to eleventh aspects, wherein the second alignment mark is made of ITO (indium tin oxide).

[0020] According to a thirteenth aspect of the present invention, there is provided the element according to the ninth aspect, wherein the first protective film is made of chromium (Cr) or an alloy containing chromium (Cr). Effect of the Invention

[0021] According to the present invention, it is possible to provide an element capable of improving operating characteristics and a method for manufacturing the same. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a cross-sectional view of a MEMS element according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the MEMS structure shown in FIG. [Diagram 3] 3A to 3C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 4] 4A to 4C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Diagram 5] 5A to 5C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 6] 6A to 6C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 7] 7A to 7C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 8] 8A to 8C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 9] 9A to 9C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 10] 10A to 10C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 11] 11A to 11C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 12] 12A to 12C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 13] 13A to 13C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 14] 14A to 14C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 15] 15A to 15C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 16] 16A to 16C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 17] FIG. 17 is a cross-sectional view illustrating a manufacturing process of the MEMS element. [Figure 18] 18A to 18C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 19] FIG. 19 is a cross-sectional view illustrating a manufacturing process of the MEMS element. [Figure 20] 20A to 20C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 21] 21A to 21C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Figure 22] 22A to 22C are cross-sectional views illustrating the manufacturing process of the MEMS element. [Diagram 23] 23A to 23C are cross-sectional views illustrating the manufacturing process of the MEMS element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, the embodiments will be described with reference to the drawings. However, the drawings are schematic or conceptual, and the dimensions and ratios of each drawing are not necessarily the same as those in reality. In addition, even when the same parts are shown between the drawings, the dimensional relationships and ratios of each may be different. In particular, the following embodiments are examples of devices and methods for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not specified by the shape, structure, arrangement, etc. of the components. In the following description, elements having the same function and configuration are given the same reference numerals, and duplicated descriptions are omitted.

[0024] [1] Structure of MEMS element 1 1 is a cross-sectional view of a MEMS element 1 according to an embodiment of the present invention. In this embodiment, the MEMS element 1 is a MEMS microphone.

[0025] The MEMS element 1 includes a glass substrate 2, an alignment mark 3 on the front surface side, an alignment mark 4 on the back surface side, and a MEMS structure 5.

[0026] The glass substrate 2 has a front surface 2-1 and a back surface 2-2 disposed opposite to each other. The glass substrate 2 has an element region AR1 in which the MEMS structure 5 is formed, and a peripheral region AR2 adjacent to the element region AR1.

[0027] The MEMS structure 5 is provided in the element region AR1 on the front surface 2-1 of the glass substrate 2. The specific configuration of the MEMS structure 5 will be described later.

[0028] An opening (through hole) 2A penetrating the glass substrate 2 is provided in the element region AR1 of the glass substrate 2. The opening 2A is disposed below the MEMS structure 5, and exposes a part of the MEMS structure 5.

[0029] An alignment mark 3 is provided on the front surface 2-1 and in the peripheral area AR2 of the glass substrate 2. An alignment mark 4 is provided on the back surface 2-2 of the glass substrate 2 and in the peripheral area AR2.

[0030] One of the manufacturing processes for devices having multiple layers (including MEMS elements) is the photolithography process using a manufacturing device (specifically, an exposure device). Alignment marks are used to form multiple layers of the element using the manufacturing device, and are used by the manufacturing device to align the layers when forming the multiple layers. The alignment marks have a predetermined shape (pattern) that can be recognized by the manufacturing device. In the photolithography process, an exposure device detects the alignment mark formed on the substrate, and the substrate and photomask are aligned using the alignment mark, and the resist is patterned using the photomask.

[0031] In a plan view, the alignment mark 4 is disposed at a position different from that of the alignment mark 3. A plan view refers to a state in which an object is viewed from the front surface of the glass substrate.

[0032] 1, each of the alignment marks 3 and 4 is shown as a simplified pattern of three squares. In reality, the alignment marks 3 and 4 have patterns whose positions and orientations can be recognized by a manufacturing device.

[0033] The alignment mark 4 includes a pattern that the manufacturing equipment can recognize from the back surface of the glass substrate 2. The alignment mark 3 includes a first pattern that the manufacturing equipment can recognize from the front surface of the glass substrate 2, and a second pattern that the manufacturing equipment can recognize from the back surface of the glass substrate 2, through the transparent glass substrate 2 and multiple transparent layers. In other words, the alignment mark 3 includes a first pattern that can be recognized from the front surface, and a second pattern that is a vertically inverted (or horizontally inverted) version of the first pattern.

[0034] This allows the manufacturing equipment to detect the alignment mark 3 by irradiating light from the rear surface of the glass substrate 2. The manufacturing equipment can also perform alignment using the alignment mark 3 and pattern a layer on the rear surface of the glass substrate 2.

[0035] (Configuration of MEMS structure 5) FIG. 2 is a cross-sectional view of the MEMS structure 5 shown in FIG.

[0036] The glass substrate 2 is provided with an opening 2A penetrating the glass substrate 2. The opening 2A has a planar shape that is, for example, circular.

[0037] A protective film 10 surrounding the opening 2A is provided on the glass substrate 2. The protective film 10 is used to protect the MEMS structure 5 when the glass substrate 2 is wet-etched.

[0038] The MEMS structure 5 is disposed so as to cover the opening 2 A formed in the glass substrate 2 .

[0039] A membrane 20 is provided on the protective film 10 and the glass substrate 2 so as to cover the opening 2A. The membrane 20 is also called a diaphragm, and is a film that vibrates due to sound pressure. The planar shape of the membrane 20 is, for example, a circle. The size of the membrane 20 is larger than the size of the opening 2A. The membrane 20 is configured by sequentially stacking an insulating layer 20A, a conductive layer 20B, and an insulating layer 20C. The conductive layer 20B functions as an electrode (vibrating electrode) of the membrane 20. The conductive layer 20B is configured of a metal, for example, molybdenum (Mo) or an alloy containing molybdenum. The insulating layer 20A and the insulating layer 20C are configured of, for example, silicon nitride (SiN).

[0040] The membrane 20 has at least one through hole 21. The through hole 21 penetrates the membrane 20. The planar shape of the through hole 21 is, for example, a circle. If the opening 2A is completely blocked by the membrane 20, a pressure difference may occur between the upper side and the lower side of the membrane 20. In order to reduce such a pressure difference, the membrane 20 is provided with the through hole 21. Note that the membrane 20 may be provided with a plurality of through holes.

[0041] A terminal 22 is provided at one end of the membrane 20. The terminal 22 is electrically connected to the conductive layer 20B. That is, the terminal 22 is configured by drawing out the conductive layer 20B in an arbitrary direction.

[0042] A backplate 24 is provided above the membrane 20 via a cavity 23. The planar shape of the backplate 24 is, for example, a circle. The backplate 24 is configured by laminating a conductive layer 24A and an insulating layer 24B in this order. The conductive layer 24A functions as an electrode (fixed electrode) of the backplate 24. The conductive layer 24A is configured of a metal, such as molybdenum (Mo) or an alloy containing molybdenum. The insulating layer 24B is configured of, for example, silicon nitride (SiN).

[0043] The aforementioned cavity 23 is provided between the membrane 20 and the back plate 24. The cavity 23 is surrounded by an insulating layer 24B.

[0044] The back plate 24 has a plurality of through holes (sound holes) 25. The through holes 25 penetrate the back plate 24. The planar shape of the through holes 25 is, for example, a circle. The plurality of through holes 25 are uniformly arranged over the entire surface of the back plate 24. The plurality of through holes 25 have the function of passing sound waves applied from the side of the back plate 24 opposite to the membrane 20 to the cavity 23.

[0045] A terminal 26 is provided at one end of the back plate 24. The terminal 26 is electrically connected to the conductive layer 24A. That is, the terminal 26 is configured by drawing out the conductive layer 24A in an arbitrary direction. The terminal 26 is exposed from the insulating layer 24B.

[0046] When sound reaches the MEMS structure 5, the sound passes through the multiple through holes 25 in the back plate 24, and sound pressure is applied to the membrane 20. This causes the membrane 20 to vibrate, and the distance between the vibrating electrode of the membrane 20 and the fixed electrode of the back plate 24 changes. When the distance between the vibrating electrode and the fixed electrode changes, the electrostatic capacitance between the vibrating electrode and the fixed electrode changes. Therefore, by applying a DC voltage between the vibrating electrode and the fixed electrode and extracting the change in electrostatic capacitance as an electrical signal, the sound pressure can be detected as an electrical signal.

[0047] [2] Manufacturing method of MEMS element 1 Next, a method for manufacturing the MEMS element 1 will be described with reference to the drawings.

[0048] As shown in Fig. 3, a glass substrate 2 is prepared. There is no particular limitation on the material of the glass substrate 2, and any glass can be used. For example, alkali-free glass or alumino-silicate glass can be used as the glass substrate 2. The alkali-free glass is glass that contains, for example, 0.1 mass % or less of an alkali component such as sodium or potassium.

[0049] The glass substrate 2 has a front surface 2-1 and a back surface 2-2. The front surface 2-1 is the surface on which the MEMS structure 5 is formed. The back surface 2-2 is the surface opposite to the front surface 2-1, and is the surface on which the opening is formed. In the drawings explaining the manufacturing method, the glass substrate 2 is illustrated with the back surface 2-2 facing up.

[0050] Subsequently, a protective film material is formed on the front surface 2-1 of the glass substrate 2, and the protective film material is patterned to form the protective film 10 and the alignment mark 3. The protective film 10 is formed in the element region AR1 in which the MEMS structure 5 is formed, and the alignment mark 3 is formed in the peripheral region AR2 adjacent to the element region AR1.

[0051] The protective film 10 has a function of protecting the MEMS structure 5 when the glass substrate 2 is wet etched from the back surface 2-2. The protective film 10 is made of a material that is resistant (etching resistance) to a glass etchant, such as chromium (Cr) or an alloy containing chromium (Cr). The alignment mark 3 is made of the same material as the protective film 10. The protective film 10 and the alignment mark 3 are made of a non-transparent material.

[0052] 4, a transparent film 4A is formed on the rear surface 2-2 of the glass substrate 2. The transparent film 4A is made of a material that can transmit alignment light emitted from a manufacturing device. For example, ITO (indium tin oxide) is used as the transparent film 4A. Alternatively, a transparent insulating film (for example, silicon nitride (SiN)) may be used as the transparent film 4A.

[0053] Subsequently, a transparent resist layer 11A is formed on the transparent film 4A as shown in Fig. 5. The resist layer 11A is made of, for example, a positive photoresist.

[0054] Next, as shown in Fig. 6, a manufacturing device (specifically, an exposure device) is used to detect the alignment mark 3 from the rear surface 2-2 of the glass substrate 2. Specifically, light for alignment is emitted from a light source provided in the manufacturing device, and the reflected light is detected by a camera. Since the transparent film 4A provided on the rear surface 2-2 of the glass substrate 2 is made of a transparent material, it is possible to detect the alignment mark 3 provided on the front surface 2-1 of the glass substrate 2. Then, using the detected alignment mark 3, the manufacturing device aligns the exposure photomask and the glass substrate 2.

[0055] 7, the resist layer 11A is exposed to light using a photomask (not shown) to partially expose the resist layer 11A. At this time, the exposure step is performed so that the exposure light is irradiated onto areas other than the pattern of the alignment marks 4 on the back surface side.

[0056] 8, the resist layer 11A is developed to remove the exposed (solubilized) portions. This forms a resist layer (resist pattern) 11 to which the pattern of the photomask is transferred. The resist pattern 11 covers the area where the alignment mark 4 is to be formed.

[0057] 9, the transparent film 4A is wet-etched using the resist pattern 11 as a mask, and then, as shown in FIG.

[0058] As a result, an alignment mark 4 is formed on the back surface 2-2 of the glass substrate 2. The alignment mark 4 is provided in the peripheral area AR2, and is arranged at a position different from the alignment mark 3 in a plan view (when viewed from the front surface or back surface of the glass substrate). The alignment mark 4 is formed in a pattern that can be recognized by a manufacturing device from the back surface. A part of the alignment mark 3 includes a pattern that is a vertically inverted (or horizontally inverted) version of the alignment mark 4.

[0059] 11, a protective film 12 is formed on the back surface 2-2 of the glass substrate 2 and on the alignment mark 4. The protective film 12 is made of a material that is resistant to a glass etching solution, and is made of the same material as the protective film 10 and the alignment mark 3 described above. The protective film 10 on the alignment mark 4 has projections and recesses corresponding to the pattern of the alignment mark 4. The projections and recesses of the protective film 10 essentially function as alignment marks.

[0060] 12, a transparent resist layer 13A is formed on the protective film 12. The resist layer 13A is made of, for example, a positive photoresist.

[0061] 13, the manufacturing device detects the alignment mark 4 from the back surface 2-2 side of the glass substrate 2. Specifically, the manufacturing device recognizes the unevenness of the protective film 12 formed on the alignment mark 4 as the alignment mark. Then, the manufacturing device aligns the exposure photomask and the glass substrate 2 using the detected alignment mark 4.

[0062] 14, the resist layer 13A is exposed to light using a photomask (not shown) to partially expose the resist layer 13A. At this time, the exposure step is performed so that the exposure light is irradiated onto the opening regions when etching the glass substrate 2.

[0063] 15, the resist layer 13 is developed to remove the exposed (solubilized) portion. This forms a resist layer (resist pattern) 13 to which the pattern of the photomask is transferred. The resist pattern 13 exposes the regions of the protective film 12 that are to be opened when the glass substrate 2 is etched.

[0064] Subsequently, as shown in FIG. 16, the protective film 12 is wet-etched using the resist pattern 13 as a mask.

[0065] 17, the resist pattern 13 is removed. This forms the protective film 12 having openings for etching the glass substrate 2. Here, the patterning of the protective film 12 is performed using the alignment marks 4 aligned with the alignment marks 3 on the front surface. This allows the openings in the protective film 12 to be formed at more accurate positions in accordance with the structures on the front surface.

[0066] 18, a MEMS structure 5 is formed on the front surface 2-1 of the glass substrate 2 in the element region AR1. A plurality of layers constituting the MEMS structure 5 are formed using the alignment marks 3. The MEMS structure 5 can be formed using a known manufacturing method.

[0067] 19, a protective layer 14 is formed on the front surface 2-1 of the glass substrate 2 so as to cover the MEMS structure 5. The protective layer 14 is made of, for example, a liquid photoresist. Then, a protective layer 15 is formed on the protective layer 14. The protective layer 15 is made of a non-photosensitive resin that is resistant to hydrofluoric acid. By covering the MEMS structure 5 with the two protective layers 14 and 15, the MEMS structure 5 can be more reliably protected when the glass substrate 2 is wet-etched.

[0068] Subsequently, a resist layer 16 is formed on the protective film 12, and this resist layer 16 is patterned. Then, a resist layer (resist pattern) 16 having the same shape as the protective film 12 is formed. The resist pattern 16 is patterned using the alignment mark 4.

[0069] 20, the glass substrate 2 is wet-etched using the protective film 12 and the resist pattern 16 as a mask. A solution containing hydrofluoric acid (hydrofluoric acid) is used as a glass etchant. As a result, an opening 2A is formed in the glass substrate 2. The opening 2A penetrates the glass substrate 2 and exposes the protective film 10. The planar shape of the opening 2A is, for example, a circle. The MEMS structure 5 is protected by the protective film 10.

[0070] 21, the resist pattern 16 on the back surface 2-2 side of the glass substrate 2 is removed. Then, the protective film 12 provided on the back surface 2-2 of the glass substrate 2 is wet etched, and the protective film 10 exposed by the opening 2A is wet etched. As a result, a part of the sacrificial layer 17 is exposed from the opening provided in the membrane.

[0071] Subsequently, as shown in FIG. 22, the protective layers 14 and 15 provided on the front surface 2-1 of the glass substrate 2 are removed.

[0072] 23, the sacrificial layer 17 is wet-etched to form a cavity 23 between the membrane and the back plate, thus completing the formation of the MEMS element 1.

[0073] [3] Effects of the embodiment In this embodiment, a transparent film is used as a material for forming the alignment mark 4 on the back surface, so that the alignment mark 3 on the front surface can be detected by passing through the transparent film from the back surface side. The alignment mark 4 on the back surface is aligned with the alignment mark 3 on the front surface and patterned. A protective film 12 made of a non-transparent material is formed on the alignment mark 4. The manufacturing device is capable of detecting unevenness on the alignment mark 4. A mask (protective film 12) used when etching the glass substrate 2 from the back surface side is aligned with the alignment mark 4 on the back surface and patterned. Then, a MEMS structure 5 is formed on the front surface of the glass substrate 2, and an opening 2A is formed on the back surface of the glass substrate 2 using the protective film 12 as a mask.

[0074] Therefore, according to this embodiment, the opening 2A of the glass substrate 2 can be formed at a more accurate position in accordance with the MEMS structure 5. This makes it possible to more appropriately set the positional relationship (relative position) between the MEMS structure 5 and the opening 2A. This makes it possible to improve the operating characteristics of the MEMS element 1.

[0075] In the above embodiment, a MEMS element (for example, a MEMS microphone) has been described as an example. However, the present embodiment is not limited to this, and can be applied to an element in which layers are formed on the front and back surfaces of the glass substrate 2.

[0076] Moreover, the above embodiment is also applicable to transparent substrates other than glass.

[0077] In the above embodiment, a microphone (also called an acoustic transducer) has been described as an example of the MEMS element, but the present invention is not limited to this. The MEMS structure 5 according to this embodiment can be applied to various elements having a MEMS mechanism, such as an acceleration sensor, a gyro sensor, a tilt sensor, and a pressure sensor.

[0078] The present invention is not limited to the above-mentioned embodiment, and various modifications can be made in the implementation stage without departing from the gist of the invention. In addition, the embodiments may be implemented in appropriate combination, and in that case, the combined effect can be obtained. Furthermore, the above-mentioned embodiment includes various inventions, and various inventions can be extracted by combinations selected from the multiple components disclosed. For example, if the problem can be solved and the effect can be obtained even if some components are deleted from all the components shown in the embodiment, the configuration from which the components are deleted can be extracted as an invention. [Explanation of symbols]

[0079] 1...MEMS element, 2...glass substrate, 2-1...front surface, 2-2...back surface, 2A...opening, 3...alignment mark, 4...alignment mark, 4A...transparent film, 5...MEMS structure, 10...protective film, 11...resist pattern, 12...protective film, 13...resist pattern, 14...protective layer, 15...protective layer, 16...resist pattern, 17...sacrificial layer, 20...membrane, 20A...insulating layer, 20B...conductive layer, 20C...insulating layer, 21...through hole, 22...terminal, 23...cavity, 24...back plate, 24A...conductive layer, 24B...insulating layer, 25...through hole, 26...terminal, AR1...element region, AR2...peripheral region.

Claims

1. forming a first alignment mark made of a non-transparent material on a front surface of a substrate made of glass; forming a transparent film on a rear surface of the substrate; performing alignment from the back surface of the substrate using the first alignment mark, and forming a first resist pattern on the transparent film; forming a second alignment mark by etching the transparent film using the first resist pattern as a mask; forming a first protective film made of a non-transparent material on the second alignment mark; performing alignment from the back surface of the substrate using the second alignment mark and the first protective film on the second alignment mark, and forming a second resist pattern on the first protective film; Etching the first protective film using the second resist pattern as a mask; A method for manufacturing an element comprising the steps of:

2. forming a structure on the front surface of the substrate after the step of etching the first protective film; Etching the substrate using the first protective film as a mask; Further comprising A method for manufacturing the element according to claim 1 .

3. The method further includes forming a second protective film made of a non-transparent material on the front surface of the substrate simultaneously with the first alignment mark; The structure is formed on the second protective film. A method for manufacturing the element according to claim 2 .

4. The structure is a MEMS structure. A method for producing the element according to claim 2 or 3.

5. In a plan view, the second alignment mark is disposed at a position different from that of the first alignment mark. A method for manufacturing the element according to claim 1 .

6. The transparent film is made of ITO (indium tin oxide). A method for manufacturing the element according to any one of claims 1 to 5.

7. The first protective film is made of chromium (Cr) or an alloy containing chromium (Cr). A method for manufacturing the element according to claim 1 .

8. A substrate having a front surface and a back surface, an opening extending from the front surface to the back surface, and made of glass; A structure provided on the front surface so as to cover the opening; a first alignment mark provided on the front surface of the substrate and made of a non-transparent material; a second alignment mark provided on the rear surface of the substrate and made of a transparent material; Equipped with In a plan view, the second alignment mark is disposed at a position different from that of the first alignment mark. element.

9. The second alignment mark is provided with a first protective film made of a non-transparent material. The device of claim 8.

10. The semiconductor device further includes a second protective film provided between the substrate and the structure and made of a non-transparent material.

10. The element according to claim 8 or 9.

11. The structure is a MEMS structure. A device according to any one of claims 8 to 10.

12. The second alignment mark is made of ITO (indium tin oxide). A device according to any one of claims 8 to 11.

13. The first protective film is made of chromium (Cr) or an alloy containing chromium (Cr). The device of claim 9.

Images