JP5922873B2 - Planar actuator and manufacturing method thereof - Google Patents

Description

  According to the present invention, an actuator unit including a first semiconductor substrate and a movable unit that is pivotally supported by a fixed unit via a torsion bar and is driven by a driving means, and a second semiconductor substrate is fixed. The present invention relates to a planar actuator having a support portion that supports an actuator portion via the portion, and a manufacturing method thereof.

  Conventionally, a semiconductor substrate includes a frame-shaped fixed portion, a torsion bar formed inside the fixed portion, and a movable portion pivotally supported by the fixed portion via the torsion bar and driven by a driving means. There is a planar type actuator having an actuator portion integrally formed with (see, for example, Patent Document 1). This planar actuator includes a driving coil and a static magnetic field generating means as driving means, and is movable using Lorentz force generated by the interaction between the magnetic field generated in the driving coil by energization and the static magnetic field generated by the static magnetic field generating means. It is the structure which rotates a part. Such a planar actuator is applied to, for example, an optical scanner that deflects and scans a light beam by providing a mirror on a movable part.

  As such a planar type actuator, a frame-shaped fixing portion, a torsion bar formed inside the fixing portion, and a shaft that is pivotally supported by the fixing portion via the torsion bar and is driven by a driving means. An actuator unit integrally formed with the first semiconductor substrate; and a support unit that is formed of the second semiconductor substrate and supports the actuator unit via the fixed unit. The applicant of the present application proposes a cavity substrate in which a groove portion is formed in advance so that a thickness corresponding to the torsion bar remains at a portion corresponding to the torsion bar (see Patent Document 2). In this type of planar actuator, since it is necessary to form a support part so as not to prevent the rotation of the movable part, the support part is formed in the same shape as the fixed part formed in a frame shape.

Japanese Patent No. 2722314 Japanese Patent Application No. 2009-062295 (Japanese Patent Application Laid-Open No. 2010-214495)

  By the way, in this type of planar actuator, design that takes into account the drive stability of the actuator section and handling characteristics when mounting the planar actuator on a mounting board is required, and the shape of the support section is devised. By doing so, it is considered that driving stability and handling properties can be improved.

  Accordingly, the present invention focuses on the above-described problems, and an object thereof is to provide a planar actuator and a manufacturing method thereof in which the shape of the support portion is devised to improve the driving stability and handling properties.

In order to achieve the above object, a planar actuator according to the present invention according to claim 1 is such that a movable part is pivotally supported by a torsion bar inside a frame-like fixed part so as to be rotatable, and at least corresponds to the torsion bar. An actuator portion formed of a first semiconductor substrate having a groove portion formed by leaving a thickness corresponding to the thickness of the torsion bar at a portion; and a second semiconductor substrate formed in a shape different from that of the fixing portion. A support portion that supports the actuator portion, and the fixing portion is joined to the support portion via an etching stop layer between the first and second semiconductor substrates.

In order to achieve the above object, a planar actuator manufacturing method according to a fifth aspect of the present invention includes a frame-shaped fixing portion, a torsion bar formed inside the fixing portion, and the torsion bar. An actuator unit that is integrally formed with a first semiconductor substrate and a movable unit that is pivotally supported by the fixed unit and is driven by a driving unit, and the actuator unit that is formed of a second semiconductor substrate via the fixing unit. A cavity substrate having a support portion for supporting an actuator portion and having a groove portion formed in advance so that a thickness corresponding to the torsion bar remains at least in a portion corresponding to the torsion bar as the first semiconductor substrate. In the planar actuator manufacturing method formed by using, etching from the back side of the semiconductor substrate corresponds to at least the torsion bar. Forming a groove substrate as a first semiconductor substrate by removing the thickness corresponding to the torsion bar so that a thickness corresponding to the torsion bar remains, and forming a cavity substrate on the back surface of the first semiconductor substrate; A step of bonding two semiconductor substrates, a step of patterning and etching the surface of the first semiconductor substrate, removing portions other than the fixed portion, the torsion bar and the movable portion, and forming the actuator portion; And patterning the back surface of the second semiconductor substrate, etching to form a shape different from that of the fixed portion, removing portions other than the support portion, and forming the support portion in the order described above. .

In order to achieve the above object, a planar actuator manufacturing method according to the present invention according to claim 8 includes a frame-shaped fixing portion, a torsion bar formed inside the fixing portion, and the torsion bar. An actuator unit that is integrally formed of a first semiconductor substrate and a movable unit that is pivotally supported by the fixed unit and driven by a driving means, and a second semiconductor substrate that is formed through the fixing unit. A cavity in which a groove portion is formed in advance so that a thickness corresponding to the torsion bar remains at least in a portion corresponding to the torsion bar as the first semiconductor substrate. In a planar actuator manufacturing method formed using a substrate, etching is performed from the back surface side of the semiconductor substrate so that at least the torsion bar is Forming a groove substrate as a first semiconductor substrate by removing the portion corresponding to the torsion bar so as to leave a thickness corresponding to the torsion bar, and from the surface side of the second semiconductor substrate; Etching to form a groove allowing rotation of the movable part, forming the support part, attaching the second semiconductor substrate to the back surface of the first semiconductor substrate, Patterning and etching the surface of the first semiconductor substrate, removing portions other than the fixed portion, the torsion bar, and the movable portion, and forming the actuator portion in the order described above .

According to the planar actuator of the present invention, the support portion is formed in a shape different from that of the fixed portion. Specifically, for example, the frame outer surface of the support portion is substantially flush with the frame outer surface of the fixed portion. The support portion is formed in a frame shape so that the frame width of the portion is wider than the frame width of the fixed portion, or a cavity substrate having a groove portion that allows the movable portion to rotate as the second semiconductor substrate. Since the strength of the support portion can be increased by forming or the like, driving stability and handling properties can be improved. The etching stop layer can join the fixing portion of the first semiconductor substrate and the support portion of the second semiconductor substrate, and can stop the etching of the first semiconductor substrate and the second semiconductor substrate.

It is a top view of a first embodiment of a planar actuator according to the present invention. It is sectional drawing of the planar type actuator shown in FIG. It is a top view of the 1st semiconductor substrate which consists of a cavity board | substrate. It is a manufacturing process figure explaining the manufacturing method of the planar type actuator of the said 1st Embodiment. FIG. 5 is a manufacturing process diagram following FIG. 4; It is sectional drawing of 2nd Embodiment of the planar type actuator by this invention. It is a top view of the 2nd semiconductor substrate which consists of a cavity board | substrate. It is a manufacturing-process figure explaining the manufacturing method of the planar type actuator of the said 2nd Embodiment. FIG. 9 is a manufacturing process diagram following FIG. 8; It is a figure which shows another structural example of the planar type actuator in the said 2nd Embodiment, and is a top view. It is sectional drawing of the planar type actuator shown in FIG. It is a figure which shows another structural example of the planar type actuator in the said 2nd Embodiment, and is a top view. It is sectional drawing of the planar type actuator shown in FIG.

Embodiments of a planar actuator according to the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 is a top view of a planar actuator according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line A-O-B in FIG.
1 and 2, a planar actuator 1 according to the present embodiment is a two-dimensionally driven electromagnetic drive type actuator that deflects a light beam from a light source (not shown) in two orthogonal directions. Part 3.

  The actuator unit 2 includes a fixed portion 4, outer torsion bars 5a and 5a, an outer movable part 6a, inner torsion bars 5b and 5b, and an inner movable part 6b formed by a first semiconductor substrate 7 made of single crystal silicon. It is formed integrally. Each of the movable parts 6a and 6b is driven by a driving means constituted by a driving coil 8 that generates a magnetic field by energization and a static magnetic field generating means (not shown) described later. In the present embodiment, as shown in FIGS. 2 and 3, the actuator unit 2 has a thickness corresponding to the outer torsion bars 5a and 5a as the first semiconductor substrate 7, as shown in FIGS. Each of the grooves 9a having a trapezoidal cross section is formed in advance so that a portion corresponding to the inner torsion bars 5b, 5b and the inner movable part 6b has a thickness corresponding to the inner torsion bars 5b, 5b. It is formed by using a cavity substrate in which a groove 9b having a trapezoidal cross section is formed in advance so as to remain. As will be described later, the first semiconductor substrate 7 composed of the cavity substrate is bonded to the second semiconductor substrate 10 forming the support portion 3 via the protective layer 11, and then the first semiconductor substrate 7 is etched. Except for the fixed part 4, the torsion bars 5a, 5a, 5b, 5b and the movable parts 6a, 6b, the actuator part 2 shown in FIG. 2 is formed. The protective layer 11 is a layer made of a silicon oxide film or the like, and serves as a stop layer when the first semiconductor substrate 7 and the second semiconductor substrate 10 are etched. The actuator unit 2 has a surface opposite to the support unit 3 covered with a protective layer 12 such as a silicon oxide film. The protective layer 12 serves as an insulating layer between the drive coil 8 and the first semiconductor substrate 7.

  The fixing part 4 is formed in a frame shape as shown in FIG. Inside the fixed portion 4, a frame-like outer movable portion 6a is rotatably supported via a pair of outer torsion bars 5a and 5a. Inside the outer movable portion 6a, the inner movable portion 6b is pivotally supported via inner torsion bars 5b and 5b whose axial directions are perpendicular to the outer torsion bars 5a and 5a. A reflection mirror 13 for reflecting a light beam from a light source (not shown) is provided on the surface of the outer movable portion 6a opposite to the support portion 3.

  The drive coil 8 generates a magnetic field when energized. Generated by the interaction between the magnetic field generated by this energization and the static magnetic field generated by two pairs of static magnetic field generating means (not shown) arranged with the opposite magnetic poles facing each other across the outer movable portion 6a and the inner movable portion 6b. The outer and inner movable parts 6a and 6b are rotated using the Lorentz force. In this embodiment, the drive coil 8 is laid on the surface of the outer movable portion 6a opposite to the support portion 3 and can superimpose and supply electric signals for driving the outer movable portion 6a and the inner movable portion 6b. It is configured. Although not shown, both end portions of the drive coil 8 are connected to electrode terminals provided on the fixed portion 4 via a pair of outer torsion bars 5a, 5a, and an external drive circuit not shown and wire bonding, etc. Electrically connected by means. The external drive circuit is configured to supply an electric signal in which an electric signal that changes at the resonance frequency of the outer movable portion 6a and an electric signal that changes at the resonance frequency of the inner movable portion 6b are superimposed. Thereby, the inner movable part 6b can be rotated without separately providing the drive coil 8 in the inner movable part 6b. Thus, since it is not necessary to provide a drive coil in the periphery of the inner movable part 6b, the reflection mirror 13 can be provided on the entire surface of the inner movable part 6b.

  The support part 3 supports the fixing part 4, is formed of a second semiconductor substrate 10 made of single crystal silicon, and has a shape different from that of the fixing part 4. Generally, the support part 3 having higher strength as much as possible can improve the driving stability of the actuator part 2 and the handling property when the planar actuator is mounted on a mounting board. In the present embodiment, the support portion 3 is formed in a frame shape as shown in FIG. 2, and the frame width of the support portion 3 is formed wider than the frame width of the fixed portion 4. Thereby, the intensity | strength of the support part 3 is raised. In the present embodiment, the support portion 3 is formed so that the outer surface of the frame is substantially flush with the outer surface of the fixing portion 4 as shown in FIG. In this way, the strength can be increased without increasing the size of the support portion 3 in the outer direction of the frame of the fixed portion 4.

  Next, the operation of the planar actuator 1 configured as described above will be described with reference to FIGS.

  First, when an electric signal (current) in which an electric signal that changes at the resonance frequency of the outer movable portion 6a and an electric signal that changes at the resonance frequency of the inner movable portion 6b are passed through the drive coil 8, a magnetic field is generated. Lorentz force is generated by the interaction between the magnetic field and the static magnetic field generated by the static magnetic field generating means, and the outer movable portion 6a and the inner movable portion 6b are rotated by the Lorentz force. The outer movable portion 6a and the inner movable portion 6b oscillate at a period based on the respective resonance frequencies, and the light beam can be deflected and scanned by the reflection mirror 13. Since the rotational force for rotating the outer movable portion 6a and the inner movable portion 6b is proportional to the drive current value flowing through the drive coil 8, the outer movable portion can be controlled by controlling the drive current value supplied to the drive coil 8. The deflection angle (light beam deflection angle) of 6a and the inner movable part 6b can be controlled.

  With such a configuration, according to the planar actuator 1 of the present embodiment, the support portion 3 is formed in a frame shape, and the frame width is formed wider than the frame width of the fixed portion 4. Since the strength of 3 can be increased, driving stability and handling properties can be improved. Furthermore, by forming the support portion 3 so that the outer surface of the frame is substantially flush with the outer surface of the fixed portion 4, the driving stability and handling properties can be improved without increasing the size.

Next, a method for manufacturing the planar actuator 1 of the first embodiment will be described in detail.
FIG. 4 shows manufacturing steps (A) to (D) of the planar actuator 1 of the first embodiment, and FIG. 5 shows manufacturing steps (E) to (G) subsequent to FIG. is there. 4 and 5 are diagrams corresponding to cross sections taken along the line AOB in FIG. 1 in each manufacturing process.

The planar actuator 1 manufacturing method according to the present embodiment includes a step (A) of forming the protective layers 11 and 12 on both surfaces of the semiconductor substrate 7 ′ and a step of forming a cavity substrate as the first semiconductor substrate 7 (B). ), A step (C) of forming the protective layer 11 again on the first semiconductor substrate 7, a step (D) of bonding the first semiconductor substrate 7 and the second semiconductor substrate 10, and a drive coil to the first semiconductor substrate 7. Step (E) for forming 8, Step (F) for etching actuator portion 2 by etching first semiconductor substrate 7, and Step (G) for forming support portion 3 by etching second semiconductor substrate 10 And comprising.
Hereinafter, the respective steps in the present embodiment will be described.

  In the step (A), the protective layers 11 and 12 are formed on both surfaces of the semiconductor substrate 7 ′ made of single crystal silicon. As the protective layers 11 and 12, in this embodiment, an oxide film of silicon is formed using an oxidation furnace or the like.

  In the step (B), after patterning the back surface of the semiconductor substrate 7 ′, wet etching is performed from the back surface side, and as shown in FIGS. 4B and 3, the portions corresponding to the outer torsion bars 5a and 5a are formed. The outer torsion bars 5a and 5a are removed so that the thickness corresponding to the outer torsion bars 5a and 5a remains, and a groove 9a having a trapezoidal cross section is formed. The torsion bars 5b, 5b are removed so that the thickness corresponding to the torsion bars 5b remains, and a groove portion 9b having a trapezoidal cross section is formed. In this way, the first semiconductor substrate 7 composed of the cavity substrate in which the groove portions 9a and 9b are formed is formed. Here, when wet etching is performed, the etching time is accurately controlled and the etching depth is accurately controlled, so that the thickness accuracy of each of the torsion bars 5a, 5a, 5b, and 5b is increased as compared with dry etching. be able to. Note that the etching in FIGS. 4 and 5 is not limited to wet etching but may be dry etching. In this case, the cross sections of the grooves 9a and 9b are square.

  In the step (C), the protective layer 11 is formed again on the inner surfaces of the groove portions 9 a and 9 b of the first semiconductor substrate 7.

  In the step (D), the second semiconductor substrate 10 made of single crystal silicon is bonded to the back surface of the first semiconductor substrate 7 (grooves 9a and 9b forming side). Here, since the processing (step (F) and step (G)) of the first semiconductor substrate 7 and the second semiconductor substrate 10 is normally performed under reduced pressure, it remains in the grooves 9 a and 9 b of the first semiconductor substrate 7. There is a possibility that the air that has been expanded expands under reduced pressure, and the bonding surfaces of the first semiconductor substrate 7 and the second semiconductor substrate 10 are peeled off. Therefore, when etching the first semiconductor substrate 7 (step (B)), although not shown in the drawing, a communication hole for venting air is formed in advance, or the first semiconductor substrate 7 and the second semiconductor substrate 10 are bonded. Before the alignment, the grooves 9a and 9b of the first semiconductor substrate 7 may be filled with a filler.

  In the step (E), after wiring material is sputtered on the surface of the first semiconductor substrate 7, patterning is performed and unnecessary portions are etched, and although not shown, the drive coil 8 is formed in the outer movable portion 6a.

  In the step (F), the surface of the first semiconductor substrate 7 is patterned, and the protective layer 12 and the first semiconductor substrate 7 are etched to fix the fixed portion 4, the outer torsion bars 5a and 5a, the inner torsion bars 5b and 5b, and the outer movable body. The actuator portion 2 is formed by removing portions other than the portion 6a and the inner movable portion 6b. At this time, as shown in FIG. 5F, the etching is performed until reaching the protective layer 11 formed on the lower surface of the first semiconductor substrate 7 and the inner surface of the groove.

  In the step (G), the back surface of the second semiconductor substrate 10 (opposite side to the first semiconductor substrate 7) is patterned so that the support portion 3 has a frame shape and the outer surface of the frame is substantially flush with the outer surface of the fixed portion 4. In addition, the support portion 3 is formed by etching the second semiconductor substrate 10 so that the frame width is wider than the frame width of the fixed portion 4. At this time, the protective layer 11 in contact with the second semiconductor substrate 10 functions as a stop layer during etching. On the other hand, the protective layer 11 formed on the inner surfaces of the groove portions 9a and 9b of the first semiconductor substrate 7 surely prevents the back surface of the torsion bar or the like from being unnecessarily scraped during the etching and causing the surface roughness. Then, the protective layer 11 between the first semiconductor substrate 10 and the second semiconductor substrate 10 is etched, and portions other than the fixing portion 4 are removed. Finally, the portions other than the portion where the reflection mirror is formed on the surface of the first semiconductor substrate 7 are masked with a masking jig or the like, the material of the reflection mirror is sputtered, and the reflection mirror 13 is formed. The planar actuator 1 shown is formed.

Next, a planar actuator according to a second embodiment of the invention will be described.
FIG. 6 is a cross-sectional view of a planar actuator 1 according to a second embodiment of the present invention, and is a cross-sectional view along the line A-O-B as in FIG. The top view of the planar actuator 1 of the second embodiment is the same as FIG. Description of the same configuration as that of the first embodiment shown in FIG. 1 is omitted, and only different portions will be described. In addition, the operation of the planar actuator 1 in this embodiment is the same as that in the first embodiment, and a description thereof will be omitted.

  In the present embodiment, as shown in FIGS. 6 and 7, the second semiconductor substrate 10 that forms the support portion 3 has a rotation allowing groove portion 9 c that allows the outer movable portion 6 a and the inner movable portion 6 b to rotate. It is a cavity substrate formed in advance, and the cross section of the rotation allowing groove 9c is formed in a trapezoidal shape. The second semiconductor substrate 10 is bonded to the first semiconductor substrate 7 via the protective layer 11.

  With such a configuration, according to the planar actuator 1 of the present embodiment, the support portion 3 is a cavity substrate on which a rotation allowing groove portion 9c that allows rotation of the movable portions 6a and 6b is formed. Thus, since the strength of the support portion 3 can be further increased as compared with the frame-like support portion of the first embodiment, handling properties and driving stability can be further improved. Furthermore, as in the present embodiment, the support portion 3 in which the rotation allowable groove portion 9c is formed can form an air pool region in the rotation allowable groove portion 9c, and therefore the outer movable portion 6a and the inner movable portion. When 6b rotates, it functions as an air damper. Therefore, when the Q value of the outer movable part 6a and the inner movable part 6b is high and drive control is difficult, the support part 3 is caused to function as an air damper by adopting the structure of the support part 3 of the present embodiment. Therefore, the Q values of the outer movable portion 6a and the inner movable portion 6b can be lowered, and drive control becomes easy. Also, for example, a plurality of actuator chips are generally formed on a single semiconductor substrate, and a single actuator chip is formed by dicing while spraying cleaning water or the like. By adopting the structure of the part 3 and dicing by spraying cleaning water or the like from the support part 3 side, the dicing can be performed without worrying about the breakage of the actuator part 2 or the like. In the present embodiment, the shape of the upper surface of the second semiconductor substrate 10 has been described as being formed so as to be wider than the lower surface of the fixed portion 4 as shown in FIGS. Instead, it may be formed in the same shape as the lower surface of the fixed portion 4 or narrower than the lower surface of the fixed portion. Even in this case, since the support part 3 is formed so as to cover the back surface of the actuator part 2, the strength can be increased as compared with a conventional frame-like support part.

Next, a method for manufacturing the planar actuator 1 of the second embodiment will be described in detail.
FIG. 8 shows manufacturing steps (A) to (D) of the planar actuator 1 of the second embodiment, and FIG. 9 shows manufacturing steps (E) and (H) following FIG. is there. 8 and 9 are diagrams corresponding to cross sections taken along the line AOB in FIG. 1 in each manufacturing process. In addition, description is simplified about the structure same as the manufacturing method of the planar type actuator of 1st Embodiment.

The planar actuator 1 manufacturing method according to the present embodiment includes a step (A) of forming a protective layer 12 on a semiconductor substrate 7 ′, a step (B) of forming a cavity substrate as the first semiconductor substrate 7, (2) forming the protective layer 11 on the semiconductor substrate 10 (C); etching the second semiconductor substrate 12 (D) to form a support; and forming the protective layer 11 on the second semiconductor substrate 10 again. A step (E), a step (F) of bonding the first semiconductor substrate 7 and the second semiconductor substrate 10, a step (G) of forming the drive coil 8 on the first semiconductor substrate 7, and the first semiconductor substrate 7 And a step (H) of forming the actuator portion 2 by etching.
Hereinafter, the respective steps in the present embodiment will be described.

  In the step (A), the protective layer 12 is formed on the surface of the semiconductor substrate 7 'made of single crystal silicon. Then, in the step (B), similarly to the step (B) of the first embodiment, the semiconductor substrate 7 ′ is patterned and wet-etched to form the first semiconductor composed of the cavity substrate on which the groove 9a and the groove 9b are formed. A substrate 7 is formed.

  In the step (C), the protective layer 11 is formed on the surface of the second semiconductor substrate 10 made of single crystal silicon. In the step (D), after patterning the surface of the second semiconductor substrate 10, wet etching is performed to form a rotation-permissible groove 9c having a trapezoidal cross section that allows the outer movable portion 6a and the inner movable portion 6b to rotate. The support part 3 is formed. This etching is not limited to wet etching but may be dry etching. In this case, the cross section of the rotation allowing groove 9c is a square shape.

  In the step (E), the protective layer 11 is formed again on the inner surface of the rotation allowable groove 9c of the second semiconductor substrate 10.

  In the step (F), the second semiconductor substrate 10 is bonded to the back surface side of the first semiconductor substrate 7. At this time, the inside of the rotation allowable groove 9c of the second semiconductor substrate 10 may be filled with a filler as in the grooves 9a and 9b.

  In step (G), although not shown, the wiring material is sputtered and then patterned and etched to form the drive coil 8 on the outer movable portion 6a.

  In the step (H), the protective layer 12 and the first semiconductor substrate 7 are etched so that portions other than the fixed portion 4, the outer torsion bars 5a and 5a, the inner torsion bars 5b and 5b, the outer movable portion 6a and the inner movable portion 6b. The actuator part 2 is formed by removing. At this time, the protective layer 11 in contact with the first semiconductor substrate 7 functions as a stop layer at the time of etching, and the protective layer 11 formed on the inner surface of the rotation allowable groove 9c of the second semiconductor substrate 10 is etched. At times, it is possible to reliably prevent the inner surface of the rotation-permitting groove 9c from being unnecessarily shaved and causing surface roughness. Then, the protective layer 11 between the first semiconductor substrate 7 and the second semiconductor substrate 10 is etched to remove portions other than the fixed portion 4. Finally, by forming the reflection mirror 13, the planar actuator 1 shown in FIG. 6 is formed.

  In the second embodiment, the second semiconductor substrate 10 forming the support portion 3 has been described as being simply formed in a substantially concave shape with respect to the actuator portion 2 as shown in FIG. As shown in FIGS. 10 and 11 showing another configuration example, the protrusions 9d are formed in advance so as to remain in places where the rotation of the movable parts 6a and 6b in the rotation allowable groove 9c is not hindered. It is good also as what was done. Thereby, since the convex part 9d functions as a rib and the intensity | strength of the support part 3 can be further raised compared with the support part shown in FIG. 6, drive stability and handling property can further be improved.

  Moreover, in the said 2nd Embodiment, although the fixing | fixed part 4 demonstrated in the case where it formed in frame shape as shown in FIG.1 and FIG.6, it is not restricted to this, FIG. 12 which shows another structural example. As shown in FIG. 13 showing a cross section along the line AOB in FIG. 12, the fixing portion 4 has two sides parallel to the axial direction of the pair of outer torsion bars 5a, 5a in FIG. The removed shape may be used. In this case, the support 3 is also formed in a shape corresponding to the fixed portion 4 as shown in FIGS. 12 and 13. Thus, many actuator chips can be formed on one semiconductor substrate. Further, since the static magnetic field generating means can be brought closer to the outer movable portion 6a and the inner movable portion 6b, the driving force can be improved, and further, the planar actuator can be miniaturized. In the configuration shown in FIGS. 12 and 13, as shown in FIGS. 10 and 11, the convex portion 9d remains at a location that does not hinder the rotation of the movable portions 6a and 6b in the rotation allowable groove portion 9c. It is good also as what was previously formed.

  In the first and second embodiments, the actuator portion 2 has a groove portion formed in a portion corresponding to the inner movable portion 6b in addition to the portion corresponding to each torsion bar 5a, 5a, 5b, 5b. As described in the example, when the inner movable portion 6b may have the same thickness as the outer movable portion 6a and the fixed portion 4, the groove portion does not have to be formed in the portion corresponding to the inner movable portion 6b. The groove portion only needs to be formed so that the thickness corresponding to each torsion bar 5a, 5a, 5b, 5b remains at least in a portion corresponding to each torsion bar 5a, 5a, 5b, 5b. The positions other than 5a, 5b, and 5b can be appropriately determined according to the actuator design specifications.

  Moreover, in the said 1st and 2nd embodiment, although the case where the drive coil 8 was provided only in the outer side movable part 6a was demonstrated, it is not limited to this, but illustration is abbreviate | omitted. A drive coil may be provided, and an inner drive coil may be provided in the inner movable portion 6b, and an alternating current that changes at the resonance frequency of the movable portion corresponding to each drive coil may be supplied and swung. Further, in the case where the drive coils are provided in each movable part in this way, a DC current is supplied to each drive coil, and the outer movable part 6a and the inner movable part 6b are rotated at the rotation positions corresponding to the supplied drive current values. The reflection mirror 13 may be directed in a desired direction and the light beam may be deflected in that direction. Although the operation of the optical scanner has been described as an example, the present invention can be applied to other than the optical scanner. Further, in the first and second embodiments, the case where the reflection mirror 13 is formed has been described, but the reflection mirror 13 may not be provided.

  In the first and second embodiments, the case of manufacturing a two-dimensional actuator has been described. However, the present invention can also be applied to the case of manufacturing a one-dimensional actuator. Further, the present invention can be applied not only to the above-described electromagnetic drive type planar actuator, but also to any planar actuator such as an electrostatic drive type and a piezoelectric drive type.

DESCRIPTION OF SYMBOLS 1 Planar type actuator 2 Actuator part 3 Support part 4 Fixed part 5a, 5a Outer torsion bar 5b, 5b Inner torsion bar 6a Outer movable part 6b Inner movable part 7 1st semiconductor substrate 8 Drive coil (drive means)
9a, 9b Groove 9c Groove (Turnable groove)
9d Convex portion 10 Second semiconductor substrate 11 Protective layer

Claims (10)

The movable portion is rotatably supported on the frame-shaped fixing portion of the inner torsion bars, the grooves formed to leave a thickness corresponding to the thickness of the torsion bar at a site corresponding to at least the torsion bar an actuator portion which is formed in the first semiconductor substrate having,
A second semiconductor substrate having a support portion that is formed in a shape different from the fixed portion and supports the actuator portion;
The fixed part is a planar actuator joined to the support part via an etching stop layer between the first semiconductor substrate and the second semiconductor substrate.   The support portion is formed in a frame shape, the frame outer surface of the support portion is substantially flush with the frame outer surface of the fixed portion, and the frame width of the support portion is wider than the frame width of the fixed portion. The planar actuator according to claim 1, wherein the support portion is formed as described above. 2. The planar actuator according to claim 1, wherein the second semiconductor substrate is a cavity substrate having a groove portion that allows the movable portion to rotate.   4. The planar actuator according to claim 3, wherein the second semiconductor substrate has a convex portion formed at a location that does not hinder the rotation of the movable portion in the groove portion. A first semiconductor includes a frame-shaped fixed portion, a torsion bar formed inside the fixed portion, and a movable portion pivotally supported by the fixed portion via the torsion bar and driven by a driving unit. An actuator unit integrally formed with a substrate; and a support unit that is formed of a second semiconductor substrate and supports the actuator unit via the fixing unit, the first semiconductor substrate serving as at least the torsion bar In a planar actuator manufacturing method formed using a cavity substrate in which grooves are formed in advance so that a thickness corresponding to the torsion bar remains in a corresponding portion,
A cavity as the first semiconductor substrate is formed by etching from the back side of the semiconductor substrate and removing at least a portion corresponding to the torsion bar so that a thickness corresponding to the torsion bar remains. Forming a substrate;
Bonding a second semiconductor substrate to the back surface of the first semiconductor substrate;
Patterning and etching the surface of the first semiconductor substrate, removing portions other than the fixed portion, the torsion bar and the movable portion, and forming the actuator portion;
Patterning the back surface of the second semiconductor substrate, etching to have a different shape from the fixed portion, removing portions other than the support portion, and forming the support portion;
Are performed in the above order. A method for manufacturing a planar actuator.   The step of forming the support portion is such that the frame outer surface of the support portion is substantially flush with the frame outer surface of the fixed portion, and the frame width of the support portion is wider than the frame width of the fixed portion. 6. The method of manufacturing a planar actuator according to claim 5, wherein the second semiconductor substrate is etched to form the support portion in a frame shape.   The method for manufacturing a planar actuator according to claim 5, further comprising a step of forming an etching stop layer on an inner surface of the groove portion of the first semiconductor substrate after the step of forming the cavity substrate. . A first semiconductor includes a frame-shaped fixed portion, a torsion bar formed inside the fixed portion, and a movable portion pivotally supported by the fixed portion via the torsion bar and driven by a driving unit. An actuator unit integrally formed with a substrate; and a support unit that is formed of a second semiconductor substrate and supports the actuator unit via the fixing unit, the first semiconductor substrate serving as at least the torsion bar In a planar actuator manufacturing method formed using a cavity substrate in which grooves are formed in advance so that a thickness corresponding to the torsion bar remains in a corresponding portion,
A cavity as the first semiconductor substrate is formed by etching from the back side of the semiconductor substrate and removing at least a portion corresponding to the torsion bar so that a thickness corresponding to the torsion bar remains. Forming a substrate;
Etching from the surface side of the second semiconductor substrate so as to form a groove that allows rotation of the movable part, and forming the support part;
Bonding the second semiconductor substrate to the back surface of the first semiconductor substrate;
Patterning and etching the surface of the first semiconductor substrate, removing portions other than the fixed portion, the torsion bar and the movable portion, and forming the actuator portion;
Are performed in the above order. A method for manufacturing a planar actuator.   In the step of forming the support portion, the support portion is formed by etching the second semiconductor substrate so that a convex portion remains at a location that does not hinder the rotation of the movable portion in the groove portion. A method for manufacturing a planar actuator according to claim 8.   The method for manufacturing a planar actuator according to claim 8, further comprising a step of forming an etching stop layer on an inner surface of the groove portion of the second semiconductor substrate after the step of forming the support portion.

Images