JP4339863B2 - Mirror element manufacturing method - Google Patents

Description

  The present invention relates to a mirror element manufacturing method applicable to an optical switching element for communication.

  In the field of optical networks that serve as the foundation for Internet communication networks, optical MEMS (Micro Electro Mechanical System) technology has been spotlighted as a technology for realizing multi-channel, wavelength division multiplexing (WDM), and cost reduction. Optical switches have been developed using this technology (see, for example, Patent Document 1). The most characteristic component of the optical switch based on the MEMS technology is a mirror array in which a plurality of mirror elements are arranged.

  The mirror array is composed of a mirror substrate and an electrode substrate disposed to face the mirror substrate. The mirror substrate has a plurality of movable structures that act as mirrors, and a support member that rotatably supports the movable structures by a spring member such as a torsion spring. The electrode substrate is formed by forming a plurality of electrode portions corresponding to a movable structure acting as a mirror on a base substrate.

  A conventional mirror array disclosed in Patent Document 1 will be described with reference to FIG. FIG. 4 is a schematic perspective view showing configurations of the mirror substrate and the electrode substrate. FIG. 4 partially shows a mirror element which is mainly one constituent unit of the mirror array. In the mirror array, the mirror elements shown in FIG. 4 are two-dimensionally squarely arranged, for example. The mirror element includes a mirror substrate 200 on which a mirror is formed and an electrode substrate 300 on which an electrode is formed, and these are arranged in parallel.

  The mirror substrate 200 includes a plate-shaped base 210, a ring-shaped movable frame 220, and a disk-shaped mirror 230. The base 210 includes an opening that is substantially circular in plan view. The movable frame 220 is disposed in the opening of the base portion 210 and is connected to the base portion 210 by a pair of connecting portions 211a and 211b. The movable frame 220 also has an opening that is substantially circular in plan view. The mirror 230 is disposed in the opening of the movable frame 220 and is coupled to the movable frame 220 by a pair of mirror coupling portions 221a and 221b. Further, a frame portion 240 surrounding the movable frame 220 and the mirror 230 is formed around the base portion 210. The frame part 240 is fixed to the base part 210 via the insulating layer 250.

  The connecting portions 211 a and 211 b are provided in the cutouts of the movable frame 220, are constituted by torsion springs having a zigzag shape, and connect the base portion 210 and the movable frame 220. The movable frame 220 connected to the base 210 in this manner is rotatable about a rotation axis (movable frame rotation axis) passing through the connection portions 211a and 211b. Further, the mirror connecting portions 221a and 221b are provided in the notches of the movable frame 220, are constituted by torsion springs having a zigzag shape, and connect the movable frame 220 and the mirror 230. Thus, the mirror 230 connected to the movable frame 220 can be turned around a turning shaft (mirror turning shaft) passing through the mirror connecting portions 221a and 221b. The movable frame rotation axis and the mirror rotation axis are orthogonal to each other.

  On the other hand, the electrode substrate 300 includes a projecting portion 320 and a rib structure 310 that is formed integrally with the electrode substrate 300 and is disposed around the projecting portion 320. The protrusion 320 includes a third terrace 323 having a truncated pyramid shape, a second terrace 322 having a truncated pyramid shape formed on the upper surface of the third terrace 323, and a pyramid formed on the upper surface of the second terrace 322. It comprises a first terrace 321 having a table shape.

  In addition, fan-shaped electrodes 340 a, 340 b, 340 c, and 340 d are formed in a circle concentric with the mirror 230 of the opposing mirror substrate 200 on the upper surface of the electrode substrate 300 including the outer surface of the protruding portion 320. . Further, a wiring 370 is formed around the protruding portion 320 of the electrode substrate 300, and electrodes 340a to 340d are connected to the wiring 370 via lead lines 341a to 341d. In the mirror substrate 200 and the electrode substrate 300 configured as described above, the mirror 230 and the electrodes 340a to 340d corresponding to each other are disposed to face each other, and the lower surface of the base 210 and the upper surface of the rib structure 310 are joined to each other. Is formed.

  Next, a manufacturing method will be briefly described. First, the mirror substrate 200 can be formed from an SOI (Silicon On Insulator) substrate. The SOI substrate is provided with a thin silicon layer (SOI layer) via a buried insulating layer on a thick base portion made of silicon. By processing the SOI layer, the base 210, the movable frame 220, A plate-like structure such as the mirror 230 can be formed. Further, the frame portion 240 can be formed by removing the thick base portion of the SOI substrate so as to leave a frame shape. Note that the insulating layer 250 illustrated in FIG. 4 corresponds to a buried insulating layer of the SOI substrate.

  The electrode substrate 300 can be formed by etching a single crystal silicon substrate having a (100) crystal orientation on the main surface with an alkaline solution such as potassium hydroxide. As is well known, single crystal silicon has a significantly lower etching rate for alkali on the (111) plane than on the (100) plane or the (110) plane. By utilizing this phenomenon, the truncated pyramid protrusion 320 and the rib structure 310 can be formed integrally with the electrode substrate 300. As described above, after the protrusion 320 and the rib structure 310 are formed, the electrodes 340a to 340d, the lead lines 341a to 341d, and the wiring 370 are formed by forming a metal film, processing the metal film formed by a photolithography technique, or the like. Is formed.

  As described above, after the mirror substrate 200 and the electrode substrate 300 are formed, a mirror element in which the mirror 230 is movable (rotated) by applying an electric field to the electrodes 340a to 340d can be formed by bonding them together. For example, the mirror substrate 200 and the electrode substrate 300 can be bonded together by forming an AuSn layer on the upper surface of the rib structure 310 and bonding the AuSn layer and the base 210 made of silicon.

The mirror element configured as described above applies an attractive force to the mirror 230 by an electric field generated by applying individual voltages to the electrodes 340a to 340d via the wiring 370, and the mirror 230 is rotated at an angle of several degrees ( Tilt). As a feature of the optical MEMS mirror element, the rotation angle of the mirror 230 can be statically and stably rotated only to an angle uniquely determined by the structure of the electrodes 340a to 340d. Assuming that the pull-in rotation angle of the mirror 230 is θ _P and the inclination angles of the electrodes 340 a to 340 d formed on the protrusion 320 are θ, the respective relationships are represented by “θ _P = (1/3) θ”. .

  Therefore, in order to rotate the mirror 230 with as large and low voltage as possible, the electrodes 340a to 340d are arranged so as to have the same area as the mirror 230, and the inclination of the protrusion 320 on which the electrodes 340a to 340d are formed. Just increase the corner. For this purpose, for example, it is conceivable to increase the height difference of the protrusion 320.

Japanese Patent No. 3579015

  However, since the electrodes 340a to 340d, the wiring 370, and the like are formed using a photolithography technique, it is difficult to increase the height difference of the protrusion 320. For example, a resist pattern made of a photoresist is formed on a metal film formed on the electrode substrate 300 including the protruding portion 320, and the electrodes 340a to 340d and the wiring 370 are etched by using the resist pattern as a mask. It is formed. Here, as is well known, the shape of the resist pattern is reflected (transferred) on the shapes of the electrodes 340 a to 340 d and the wiring 370. Therefore, in order to form the electrodes 340a to 340d and the wiring 370 with high accuracy (position, size, etc.), the resist pattern needs to be formed with high accuracy.

  However, since the electrodes 340a to 340d are formed on the projecting portions 320 having different heights, there is a problem that a resist pattern for forming them cannot be formed with high accuracy. In the photolithography technique, exposure is performed by forming (projecting) an optical image of a pattern to be formed on a pattern forming surface. At this time, if the focus of the projected image is deviated from the pattern formation surface, the light image formed on the pattern formation surface becomes a so-called blurred image with a low contrast between the pattern boundaries. In such a state, a resist pattern with high accuracy cannot be formed. As a result, for example, the electrodes 340a to 340d cannot be formed with high accuracy.

  Here, the above-described problem due to the shift of the focal position can be solved by performing exposure a plurality of times for each different focal position or repeating the exposure and etching for each terrace having different heights. However, in these methods, since exposure is performed a plurality of times, alignment in this exposure is not easy, and the number of steps increases. As described above, conventionally, there is a problem that the electrodes 340a to 340d, the wiring 370, and the like cannot be easily formed on the electrode substrate 300 provided with the projecting portions 320 having different heights.

  On the other hand, in the electrode substrate 300, a plurality of wirings 370 are arranged on the electrode substrate 300 in a complicated manner. Such wiring cannot be arranged in the region of the rib structure 310 formed integrally with the electrode substrate 300 as described above. In other words, the rib structure 310 cannot be formed in the wiring region where the wiring 370 is provided. Further, as is well known, the wiring formed by the photolithography technique and the etching technique is disposed near the rib structure 310 for the purpose of avoiding unnecessary light irradiation at the time of exposure. It is not easy.

  For these reasons, the rib structure 310 cannot be provided so as to surround one element region centered on the protrusion 320. Thus, since the mirror substrate 200 is bonded to the electrode substrate 300 by the rib structure 310 provided partially, the bonding strength between the two cannot be sufficiently obtained, and the mirror substrate 200 peels off. A problem occurs. In order to solve this problem, a new support structure is formed on the electrode substrate 300 after the wiring and the like are formed, and the support structure together with the rib structure 310 is used for the electrode substrate 300. The mirror substrate 200 may be bonded. However, it is necessary to arrange the support structure so as not to hinder the rotating operation of the mirror 230 and the like.

  However, such a support structure is also formed by a photolithography technique or the like. Therefore, in addition to the formation of the electrodes and wirings described above, more processes are required to form a new support structure. Thus, conventionally, there has been a problem that a mirror element cannot be easily formed.

  The present invention has been made to solve the above-described problems, so that electrodes and wirings can be easily formed with high accuracy in a state where the electrode substrate and the mirror substrate can be more firmly bonded. The purpose is to do.

  A manufacturing method of a mirror element according to the present invention is a manufacturing method of a mirror device having a mirror substrate having a mirror that is rotatably supported, and an electrode substrate disposed opposite to the mirror substrate. A substantially cone-shaped projecting portion projecting from the plane is formed on the upper surface, and then a metal film is formed on the plane of the electrode substrate and the surface of the projecting portion. A resist pattern is formed, and then the metal film is etched using the first resist pattern as a mask to form a plurality of wirings on the plane, and a metal pattern is formed on the projecting portion. After removing the resist pattern, a resin layer made of an organic material is formed on the plane including the wiring and the metal pattern and the protruding portion, a resin processing layer is formed on the resin layer, and this resin processing layer is patterned. The A resin processing pattern is formed using the formed resin processing pattern as a mask to form a resin mask pattern, and then a metal pattern is etched using the resin mask pattern as a mask to form a plurality of patterns on the protrusions. Next, the region including the protruding portion of the resin mask pattern is removed to form a support structure on the electrode substrate in the region around the protruding portion, and then the support structure The mirror substrate is fixed on the upper surface. Therefore, the wiring and the electrode are formed with different mask patterns.

  In the above mirror element manufacturing method, a resin processed layer made of an inorganic material is formed on the resin layer, and a second resist pattern is formed on the resin processed layer by photolithography. By etching the resin processing layer using the resist pattern as a mask, the resin processing pattern can be formed on the resin layer. Alternatively, the resin processing layer may be formed by patterning the resin processing layer by a photolithography technique with a photosensitive resin processing layer formed on the resin layer.

  As described above, in the present invention, a planar wiring is formed using the first resist pattern, a resin mask pattern is formed by the resin processing pattern, and an electrode on the protruding portion is formed by this resin mask pattern. In addition, the support structure is formed by a part of the resin mask pattern. As a result, according to the present invention, it is possible to obtain an excellent effect that electrodes, wirings, and the like can be easily formed with high accuracy in a state where the electrode substrate and the mirror substrate can be more firmly bonded.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1, 2, and 3 are process diagrams for explaining an example of a manufacturing method of a mirror element according to an embodiment of the present invention. Here, in these drawings, a mirror element which is one structural unit of the mirror array is mainly partially shown. First, as shown in FIG. 1 (a), a single crystal silicon substrate having a main surface crystal orientation of (100) is etched with an alkaline solution such as potassium hydroxide to project onto the electrode substrate 300. Assume that the portion 320 is formed. The protrusion 320 includes a third terrace 323 having a truncated pyramid shape, a second terrace 322 having a truncated pyramid shape formed on the upper surface of the third terrace 323, and a pyramid formed on the upper surface of the second terrace 322. It is comprised from the 1st terrace 321 which has the shape of a stand. Although not shown in FIG. 1, a rib structure higher than the protrusion 320 is formed at a predetermined position on the electrode substrate 300 at the same time.

  Next, as shown in FIG. 1B, the metal film 101 is formed on the electrode substrate 300 on which the protrusions 320 are formed. For example, the metal film 101 may be formed by depositing a metal such as aluminum by a sputtering method or a vacuum evaporation method. In addition, a resist pattern (first resist pattern) 102 including a pattern for forming a wiring or the like is formed on a part of the extraction electrode on the metal film 101. For example, the resist pattern 102 can be formed by applying a photoresist on the metal film 101 to form a resist film, and then performing exposure and development.

  Here, as shown in the schematic plan view of FIG. 1C, the resist pattern 102 covers the protruding portion 320 in a range wider than a portion where the wiring and the like are formed and a region where the protruding portion 320 (electrode) is formed. And a rectangular portion. In the formation of the resist pattern 102, exposure may be performed in a state where a portion where wiring or the like is to be formed is in focus. The rectangular portion only needs to be hidden by etching of the metal film 101 using the resist pattern 102 described below so that the region where the electrode formed on the protrusion 320 is disposed is hidden. For this reason, the rectangular portion does not need a highly accurate shape, and there is no problem even if the focal position is deviated. As described above, the resist pattern 102 can be exposed in a focused state in a portion for forming a wiring and the like, and can be formed with high accuracy in position, shape, and the like.

  The metal film 101 is selectively etched using the resist pattern 102 formed in this manner as a mask, and then the resist pattern 102 is removed, so that as shown in FIG. It is assumed that the wiring 370 and the metal pattern 103 are formed. As described above, since the portion of the resist pattern 102 for forming the wiring 370 is formed with high accuracy in position, shape, etc., the wiring 370 is also in a state where the position, shape, etc. are formed with high accuracy. can get.

  Next, as shown in FIG. 1E, a resin layer 104 is formed on the electrode substrate 300 on which the wiring 370 and the metal pattern 103 are formed. In addition, an inorganic layer (resin processing layer) 105 made of, for example, metal is formed on the resin layer 104. The resin layer 104 should just be formed higher than the protrusion part 320. FIG. In this example, the resin layer 104 is formed at the same height as a rib structure (not shown) formed at the same time as the protruding portion 320. For example, the resin layer 104 may be made of polyimide, and may be formed by applying a solution in which polyimide is dissolved by a predetermined application method, and curing by heating. Further, for example, the inorganic layer 105 may be formed by depositing a metal such as titanium by a sputtering method or a vacuum evaporation method.

  Next, a resist pattern (second resist pattern) 106 is formed by a known photolithography technique, and the inorganic layer 105 is patterned (processed) by selective etching using the resist pattern 106, whereby FIG. As shown in FIG. 4, an inorganic mask pattern (resin processing pattern) 107 is formed on the resin layer 104. Here, as shown in the schematic plan view of FIG. 2 (g), the resist pattern 106 is shown in FIG. 4 with four fan-shaped portions forming the fan-shaped electrodes 340a to 340d shown in FIG. This is provided with a portion for forming the lead lines 341a to 341d and a portion for covering a region other than these. In the formation of the resist pattern 106, since the patterning is performed on the inorganic layer 105 formed on the resin layer 104 whose surface is flattened, if exposure is performed at the same focal position over the entire region, the resist pattern 106 is formed. Well, the position and shape can be formed with high accuracy. For this reason, the inorganic mask pattern 107 is also formed with high accuracy in position, shape, and the like.

  Next, the resin layer 104 is selectively etched using the inorganic mask pattern 107 as a mask, so that the resin mask pattern 108 is formed as shown in FIG. For example, the resin mask pattern 108 can be formed by selectively removing the resin layer 104 by reactive ion etching using oxygen gas plasma. At this time, the etching may be performed until the surface of the metal pattern 103 is exposed at the bottom of the opening region to be removed. According to the reactive ion etching, it is possible to etch the resin layer 104 with a high selection ratio and with a vertical anisotropy. Further, as described above, since the inorganic mask pattern 107 is formed with high accuracy in position and shape, the resin mask pattern 108 is also formed in a state with high accuracy in position and shape. In the etching process of the resin layer 104, the resist pattern 106 made of an organic material is also removed at the same time.

Next, the metal pattern 103 is patterned using the formed resin mask pattern 108 as a mask, so that the electrodes 340b and 340d are formed as shown in FIG. 2 (i). Although not shown in FIG. 2I, an electrode 340a, an electrode 340c, and lead lines 341a to 341d are also formed at the same time. For example, the electrodes and lead lines can be formed by selectively removing the metal pattern 103 by reactive ion etching using a chlorine-based etching gas such as Cl ₂ . Further, as described above, since the resin mask pattern 108 is formed with high accuracy, these electrodes and lead lines are formed with high accuracy in position and shape. Thus, according to the present manufacturing method example, each electrode can be easily formed with high positional accuracy and high dimensional accuracy even on the protrusion 320 having a large step.

  Next, as shown in FIG. 2J, a resist pattern 109 is formed on the inorganic mask pattern 107. Here, as shown in the schematic plan view of FIG. 2 (k), the resist pattern 109 is a pattern in which a rectangular region including a protruding portion is opened. Next, the inorganic mask pattern 107 is selectively etched using the resist pattern 109 as a mask, and then the resin mask pattern 108 is selectively etched away by reactive ion etching using oxygen gas plasma. As shown in FIG. 3L and FIG. 3M, the support structure 111 is formed on the electrode substrate 300.

  According to the above etching process using the new inorganic mask pattern 110 patterned using the resist pattern 109 as a mask, the resin mask pattern 108 made of an organic material can be patterned with a high selectivity. By this patterning, the support structure 111 can be easily formed. In addition, the resist pattern 109 made of an organic material is also removed by this etching process. Note that the inorganic mask pattern 110 is not shown in the plan view of FIG.

  By bonding the electrode substrate 300 configured as described above and the mirror substrate 200, the mirror 230 can be moved (rotated) by applying an electric field to the electrodes 340a to 340d as shown in the sectional view of FIG. ) Can be formed. In the mirror element shown in FIG. 3 (n), the upper surface of the inorganic mask pattern 110 formed on the upper surface of the support structure 111 of the electrode substrate 300 and the rib structure 310 (not shown) and the base 210 of the mirror substrate 200 are bonded and fixed. Has been.

  In the electrode substrate 300 (mirror element) illustrated in FIGS. 3 (m) and 3 (n) configured as described above, electrodes between element regions adjacent in the vertical direction (inter-element region) on the paper surface, etc. A rib structure 310 is formed in a part other than the wiring region provided with. Focusing on one element region, the rib structure 310 is formed in addition to the wiring region around the element region. In addition, in the electrode substrate 300, the support structure 111 having the same height as the rib structure 310 is provided in the region where the rib structure 310 around each element region (inter-element region) is not provided. Is formed (fixed) separately. The upper surface of the support structure 111 and the upper surface of the rib structure 310 are disposed on the same plane.

  As shown in FIGS. 3M and 3N, according to the present mirror element, the upper surface of the support structure 111 is bonded to the element peripheral portion of the base 210 of the mirror substrate 200. According to the conventional mirror element shown in FIG. 4, the region is a space. As described above, since the region that has not been conventionally bonded is bonded by the support structure 111 provided separately from the electrode substrate 300, according to the present mirror element, the electrode substrate 300 and the mirror substrate 200 are bonded. Can be bonded more firmly, and separation between the mirror substrate 200 and the electrode substrate can be suppressed. In the above description, the rib structure is formed at the same time as the protruding portion. However, the present invention is not limited to this. When forming the protruding portion, the mirror substrate may be supported only by the support structure 111 formed by patterning the resin mask pattern 108 without forming the rib structure. For example, the support structure may be formed so as to surround one element region around the protrusion 320. In this case, a support structure is formed at the boundary between adjacent element regions.

  The mirror substrate 200 will be described with a plate-shaped base 210, a ring-shaped movable frame 220, and a disk-shaped mirror 230. The base 210 includes an opening that is substantially circular in plan view. The movable frame 220 is disposed in the opening of the base portion 210 and is connected to the base portion 210 by a pair of connecting portions 211a and 211b. The movable frame 220 also has an opening that is substantially circular in plan view. The mirror 230 is disposed in the opening of the movable frame 220 and is coupled to the movable frame 220 by a pair of mirror coupling portions 221a and 221b. In FIG. 3 (n), the connecting portion and the mirror connecting portion are omitted. Further, a frame portion 240 surrounding the movable frame 220 and the mirror 230 is formed around the base portion 210. The frame part 240 is fixed to the base part 210 via the insulating layer 250.

  The connecting portions 211 a and 211 b are provided in the cutouts of the movable frame 220, are constituted by torsion springs having a zigzag shape, and connect the base portion 210 and the movable frame 220. In this way, the movable frame 220 connected to the base 210 is rotatable about a rotation axis (movable frame rotation axis) passing through the connection portion. Further, the mirror connecting portions 221a and 221b are provided in the notches of the movable frame 220, are constituted by torsion springs having a zigzag shape, and connect the movable frame 220 and the mirror 230. Thus, the mirror 230 connected to the movable frame 220 can be rotated around a rotation axis (mirror rotation axis) passing through the mirror connection portion. Note that the movable frame rotation axis and the mirror rotation axis are perpendicular to each other.

  The mirror element configured in this manner gives an attractive force to the mirror 230 by an electric field generated by applying individual voltages to the electrodes 340a to 340d through the wiring 370, and tilts the mirror 230 at an angle of several degrees. is there. When no voltage is applied to the electrodes 340a to 340d, the mirror 230 is in a state (initial position) substantially parallel to the electrode substrate 300 (base 210). In this state, tilting of the mirror 230 can be controlled by applying individual voltages to the electrodes 340a to 340d.

  In the above description, the resin mask pattern 108 is patterned by etching using the inorganic mask pattern (resin processing pattern) 107 as a mask. However, the present invention is not limited to this. For example, a resin processing layer made of a photosensitive material containing silicon or metal is formed on the resin layer 104, and the resin processing layer is patterned by a photolithography technique, and oxygen plasma is applied to the formed pattern. By doing so, a resin processing pattern may be formed. For example, since polydimethylsiloxane has photosensitivity, it can be patterned by photolithography. In addition, a novolac-type photoresist to which a silicon-containing polymer is added can be applied to a resin processing layer (“Semiconductor Dry Etching Technology”, Sangyo Tosho Co., Ltd., pp.211-212, October 6, 1992). ). The pattern formed in this manner has high resistance to active oxygen such as oxygen plasma, and thus has a high etching selectivity with respect to the resin layer 104. For this reason, according to the above-mentioned resin processing pattern, the resin layer 104 can be selectively etched by using oxygen plasma.

  By the way, in the example of the manufacturing method described above, in the formation of the support structure 111 using FIGS. 2J to 3L, selective etching is performed using the inorganic mask pattern 110 made of metal (titanium) as a mask. However, it is not limited to this. For example, by forming the resin layer 104 from a photosensitive polyimide resin, the support structure 111 can be formed by selectively irradiating (exposing) light. In this case, after the shape of the support structure 111 is formed, it is cured by heating or the like.

It is process drawing which shows typically the example of the manufacturing method of the mirror element in embodiment of this invention. It is process drawing which shows typically the example of the manufacturing method of the mirror element in embodiment of this invention. It is process drawing which shows typically the example of the manufacturing method of the mirror element in embodiment of this invention. It is a perspective view which shows the structural example of a mirror element.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Metal film, 102 ... Resist pattern (first resist pattern), 103 ... Metal pattern, 104 ... Resin layer, 105 ... Inorganic layer, 106 ... (Second resist pattern) Resist pattern, 107 ... Inorganic mask pattern, 108 ... Resin mask pattern, 109 ... resist pattern, 110 ... inorganic mask pattern, 111 ... support structure, 200 ... mirror substrate, 210 ... base, 211a, 211b ... connecting portion, 220 ... movable frame, 221a, 221b ... mirror connecting portion, 230 ... Mirror, 240 ... Frame, 320 ... Projection, 321 ... First terrace, 322 ... Second terrace 322, 323 ... Third terrace, 340a, 340b, 340c, 340d ... Electrode, 341a, 341b, 341c, 341d ... leader line, 370 ... wiring.

Claims (3)

A method of manufacturing a mirror device having a mirror substrate having a mirror supported so as to be rotatable, and an electrode substrate disposed opposite to the mirror substrate,
A first step in which a substantially conical protruding portion protruding from the plane is formed on the plane of the electrode substrate;
A second step in which a metal film is formed on the surface of the flat surface and the protruding portion of the electrode substrate;
A third step in which a first resist pattern is formed on the metal film by a photolithography technique;
A fourth step of etching the metal film using the first resist pattern as a mask to form a plurality of wirings on the plane and forming a metal pattern on the protrusions;
A fifth step in which the first resist pattern is removed;
A sixth step in which a resin layer made of an organic material is formed on the plane including the wiring and the metal pattern and the protruding portion;
A seventh step in which a resin processing layer is formed on the resin layer;
An eighth step of patterning the resin processing layer to form a resin processing pattern;
A ninth step in which the resin mask pattern is formed by etching the resin layer using the resin processing pattern as a mask;
A tenth step of etching the metal pattern using the resin mask pattern as a mask to form a plurality of electrodes on the protruding portion;
An eleventh step in which a support structure is formed on the electrode substrate in a region around the protrusion by removing the region including the protrusion of the resin mask pattern;
And a twelfth step in which the mirror substrate is fixed to the upper surface of the support structure. In the manufacturing method of the mirror element of Claim 1,
The resin processing layer made of an inorganic material is formed on the resin layer,
A state in which a second resist pattern is formed on the resin processing layer by a photolithography technique,
The method of manufacturing a mirror element, wherein the resin processing layer is etched using the second resist pattern as a mask so that the resin processing pattern is formed on the resin layer. In the manufacturing method of the mirror element of Claim 1,
The resin processed layer having photosensitivity is formed on the resin layer,
A method of manufacturing a mirror element, characterized in that the resin processing layer is patterned by a photolithography technique to form the resin processing pattern.

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