Inspection methods for movable devices

Abstract

To provide a technique for rationalizing inspection of a movable device.SOLUTION: A movable device 100 includes a movable part 110, a driving part 120 for driving the movable part 110, a support frame 130 for surrounding the movable part 110 and supporting the driving part 120, an electrode part 140 which is electrically connected to the driving part 120, and a false electrode part 150 which is electrically insulated from the driving part 120, wherein the electrode part 140 and the false electrode part 150 are provided on the support frame 130. The false electrode part 150 and a probe are brought into contact with each other at the time of inspection of the movable device 100, fixation at the time of inspection is strengthened, and fluttering of the support frame 130 due to vibration in operation can be suppressed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This disclosure relates to , possible a method for inspecting a movable device.

Background Art

[0002] Conventionally, movable devices having movable parts driven by electricity are known. Among the movable devices, there are MEMS devices formed by microfabrication technology. Also, an optical scanning device that scans light using a movable device is known.

[0003] Inspection of a movable device is performed by bringing a probe into contact with an electrode of the movable device. Some movable devices have electrodes provided on one side of the movable device (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the inspection of the movable device of Patent Document 1, due to vibration during operation, normal probe contact may not be obtained, and sufficient test results may not be obtained. Therefore, inspection is performed after assembling the movable device into a package, but the inspection after assembly may increase costs due to an increase in inspection man-hours or the number of parts.

[0006] This disclosure provides a technique for rationalizing the inspection of a movable device.

Means for Solving the Problems

[0007] One aspect of this disclosure is A method for inspecting a movable device, wherein the movable device comprises a movable part, a drive unit for driving the movable part, a support frame surrounding the movable part and supporting the drive unit, an electrode part electrically connected to the drive unit, and a false electrode part electrically insulated from the drive unit, wherein the electrode part and the false electrode part are provided on the support frame, and the false electrode part is arranged in a plurality of positions symmetrically with respect to the center of the support frame in a plan view, and the plurality of false electrode parts arranged symmetrically with respect to each other are brought into contact with different inspection probes, and the plurality of false electrode parts arranged symmetrically with respect to the inspection probe is fixed in contact with the inspection probe in such a way as to suppress vibration of the support frame when the movable device is in operation. to provide a movable device Testing method < [Effects of the Invention]

[0008] According to one aspect of this disclosure, a technique for streamlining the inspection of movable devices can be provided. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows an example configuration of a movable device in one embodiment. [Figure 2] This is a partial cross-sectional view of an inspection device according to one embodiment. [Figure 3] This is a partially enlarged view of an inspection device according to one embodiment. [Figure 4] This figure shows a method for fixing a movable device according to one embodiment. [Figure 5] This figure shows a probe used to inspect a movable device in one embodiment. [Figure 6] This figure shows the test results of the movable devices for the reference example, comparative example, and example. [Figure 7] This figure shows an example configuration of an optical scanning device using a movable device according to one embodiment. [Modes for carrying out the invention]

[0010] Embodiments of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same reference numerals are used for the same components, and redundant descriptions are omitted as appropriate.

[0011] In each drawing, orthogonal coordinates having X, Y, and Z axes are used to represent direction. Furthermore, the X-axis direction is represented as left-right, the Y-axis direction as front-back, and the Z-axis direction as up-down, but these directional representations are not limited to the directions of the embodiments of this disclosure.

[0012] The configuration of a movable device 100 according to one embodiment will be described below.

[0013] <Configuration of movable device> FIG. 1 is a diagram showing a configuration example of the movable device 100 of the present embodiment. The movable device 100 is a MEMS device formed by a microfabrication technique, and is, for example, a MEMS mirror.

[0014] The movable device 100 includes a movable part 110, a drive part 120, a support frame 130, an electrode part 140, and a dummy electrode part 150.

[0015] The movable part 110 is a movable body driven by the drive part 120, and is, for example, a mirror body. There are through holes 115 penetrating in the Z-axis direction (vertical direction) around the movable part 110.

[0016] The movable part 110 includes a mirror 111, a mirror support 112, torsion beams 113A and 113B, and connecting beams 114A and 114B.

[0017] The drive part 120 is a drive source for driving the movable part 110. The drive part 120 drives the movable part 110 by a piezoelectric drive method, but may drive the movable part 110 by an electromagnetic drive method or an electrostatic drive method.

[0018] The drive part 120 includes drive beams 121A and 121B, and drive sources 122A and 122B.

[0019] The support frame 130 surrounds the periphery of the movable part 110. The support frame 130 supports the drive part 120. The shape of the support frame 130 is, for example, rectangular.

[0020] The support frame 130 includes frame bodies 131A, 131B, 132A, and 132B that constitute each side.

[0021] The electrode part 140 is a conductor electrically connected to the drive part 120. The electrode part 140 is supported by the support frame 130. [[ID=​​​​

[0023] The false electrode portion 150 is a false conductor electrically insulated from the drive unit 120. The false electrode portion 150 is supported by the support frame 130.

[0024] The false electrode section 150 is equipped with false electrode pads 151A, 151B, 152A, 152B, 153A, 153B, 154A, 154B, 155A, 155B, 156A, 156B, 157A, 157B, 158A, and 158B.

[0025] The electrode pads 141A to 142B are positioned symmetrically with respect to the center O of the support frame 130 in a plan view. The electrode pads 141A to 142B are provided on the first frame body 131A which forms one side of the support frame 130, and on the second frame body 131B which forms the opposite side opposite to that side. Note that a plan view means viewing the movable device 100 from a line of sight in the Z-axis direction (directly from above).

[0026] The false electrode pads 151A to 158B are positioned symmetrically with respect to the center O of the support frame 130 in a plan view. The false electrode pads 151A to 154B are provided on the frame members 131A to 132B that make up each side of the support frame 130 so as to surround the movable part 110.

[0027] The false electrode pads 155A to 156B may be provided at the ends of the frame members 131A to 132B that constitute each corner of the support frame 130.

[0028] The false electrode pads 157A to 158B may be provided in the central part of the first frame body 131A that forms one side of the support frame 130, and in the central part of the second frame body 131B that forms the opposite side opposite to that side.

[0029] The electrode pads 141A to 142B and the false electrode pads 151A to 158B are the positions where the probe makes contact during the inspection of the movable device 100, which will be described later.

[0030] The mirror 111 is formed on the upper surface of the mirror support 112.

[0031] The mirror support 112 supports the mirror 111. Torsion beams 113A and 113B are connected to each end of the mirror support 112 in the X-axis direction (left-right direction).

[0032] The twisted beams 113A and 113B extend in the X-axis direction (left-right direction). The twisted beams 113A and 113B support the mirror support 112 from both sides. The twisted beams 113A and 113B constitute the pivot axis SA of the mirror 111.

[0033] The twisting of the torsion beams 113A and 113B causes the mirror 111 to swing around the pivot axis SA. The torsion beams 113A and 113B are connected to the connecting beams 114A and 114B.

[0034] The connecting beams 114A and 114B are, for example, C-shaped in plan view. The ends of the twisted beams 113A and 113B are connected to the central part of the C-shape of the connecting beams 114A and 114B. The connecting beams 114A and 114B connect the twisted beams 113A and 113B to the drive beams 121A and 121B.

[0035] Drive beams 121A and 121B are connected to the C-shaped ends of connecting beams 114A and 114B.

[0036] The drive beams 121A and 121B are provided in pairs so as to sandwich the mirror 111 in a direction perpendicular to the pivot axis SA. The ends of the drive beams 121A and 121B are connected to the frames 131A and 131B of the support frame 130. Drive sources 122A and 122B are provided on the drive beams 121A and 121B.

[0037] The drive sources 122A and 122B are, for example, piezoelectric elements (piezoelectric thin films). The drive sources 122A and 122B are provided with upper electrodes 143A and 143B and lower electrodes 144A and 144B.

[0038] The upper electrodes 143A and 143B are connected to electrode pads 141A and 141B. The lower electrodes 144A and 144B are connected to electrode pads 142A and 142B.

[0039] The first drive source 122A extends or retracts in response to the drive voltage applied between the first electrode pad 141A and the second electrode pad 142A. The second drive source 122B extends or retracts in response to the drive voltage applied between the third electrode pad 141B and the fourth electrode pad 142B.

[0040] The first drive beam 121A vibrates in the Z-axis direction (vertical direction) in response to the extension or contraction of the first drive source 122A. The second drive beam 121B vibrates in the Z-axis direction (vertical direction) in response to the extension or contraction of the second drive source 122B.

[0041] By alternately applying drive voltages with reversed potentials between the first drive source 122A and the second drive source 122B, the first drive beam 121A and the second drive beam 121B vibrate alternately in the Z-axis direction (vertical direction) on both sides of the mirror 111.

[0042] The alternating vibrations of the first drive beam 121A and the second drive beam 121B cause the mirror 111 to oscillate around the axis SA, with the torsion beams 113A and 113B acting as the pivot axis.

[0043] The first drive beam 121A is supported by the first frame 131A. The second drive beam 121B is supported by the second frame 131B.

[0044] Each end of the first frame 131A is connected orthogonally to the end of the third frame 132A and the end of the fourth frame 132B. Each end of the second frame 131B is connected orthogonally to the other end of the third frame 132A and the other end of the fourth frame 132B.

[0045] The first electrode pad 141A and the third electrode pad 141B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view.

[0046] The second electrode pad 142A and the fourth electrode pad 142B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view.

[0047] The linear false electrode pads 151A, 151B, 152A, 152B, 153A, 153B, 154A, and 154B allow for an expansion of the probe's contact area.

[0048] The dot-shaped false electrode pads 155A, 155B, 156A, 156B, 157A, 157B, 158A, and 158B allow for the installation of pads in locations where space is limited. The dot shape is generally square, but circular or other shapes are also acceptable.

[0049] The first false electrode pad 151A, the second false electrode pad 151B, the third false electrode pad 152A, and the fourth false electrode pad 152B are provided on the first frame 131A and the second frame 131B of the support frame 130, which is opposite the first frame 131A.

[0050] The first false electrode pad 151A and the second false electrode pad 151B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view. The third false electrode pad 152A and the fourth false electrode pad 152B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view.

[0051] The fifth false electrode pad 153A, the sixth false electrode pad 153B, the seventh false electrode pad 154A, and the eighth false electrode pad 154B are provided on the third frame 132A and the fourth frame 132B of the support frame 130, which is opposite the third frame 132A.

[0052] The fifth false electrode pad 153A and the sixth false electrode pad 153B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view. The seventh false electrode pad 154A and the eighth false electrode pad 154B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view.

[0053] The ninth false electrode pad 155A, the tenth false electrode pad 155B, the eleventh false electrode pad 156A, and the twelfth false electrode pad 156B are provided at the ends of the frame members 131A, 131B, 132A, and 132B that constitute each corner of the support frame 130.

[0054] The ninth false electrode pad 155A and the tenth false electrode pad 155B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view. The eleventh false electrode pad 156A and the twelfth false electrode pad 156B are positioned point-symmetrically with respect to the center O of the support frame 130 in a plan view.

[0055] The 13th false electrode pad 157A and the 14th false electrode pad 157B are located in the center of the first frame 131A, which forms one side of the support frame 130. The 15th false electrode pad 158A and the 16th false electrode pad 158B are located in the center of the second frame 131B, which forms the opposite side of the support frame 130.

[0056] The 13th false electrode pad 157A and the 14th false electrode pad 157B are located between the first electrode pad 141A and the second electrode pad 142A. The 15th false electrode pad 158A and the 16th false electrode pad 158B are located between the third electrode pad 141B and the fourth electrode pad 142B.

[0057] The 13th false electrode pad 157A and the 14th false electrode pad 157B are positioned point-symmetrically with respect to the center O of the support frame 130. The 15th false electrode pad 158A and the 16th false electrode pad 158B are positioned point-symmetrically with respect to the center O of the support frame 130.

[0058] As described above, the false electrode pads 151A to 158B are positioned symmetrically with respect to the center O of the support frame 130 in a plan view. Therefore, the fixation of the movable device 100 by the probe during inspection is strengthened, and the flapping of the support frame 130 due to vibrations during operation can be suppressed.

[0059] The movable device 100 may also be equipped with either linear false electrode pads 151A to 154B or dot-shaped false electrode pads 155A to 158B.

[0060] Furthermore, the third frame 132A and the fourth frame 132B facing the third frame 132A do not support the drive unit 120, and vibrations from the drive unit 120 are relatively difficult to transmit to them. Therefore, the movable device 100 may be equipped with false electrode pads 151A to 152B only on the first frame 131A, which supports the drive unit 120, and the second frame 131B facing the first frame 131A.

[0061] Furthermore, the movable device 100 may be provided with false electrode pads 153A to 154B only at the ends of the frame members 131A to 132B that constitute each corner of the support frame 130.

[0062] <Inspection methods for movable devices> The inspection method for the movable device 100 will be described below. Figure 2 is a partial cross-sectional view of the inspection device 200 of this embodiment, and Figure 3 is a partial enlarged view of the inspection device 200 of this embodiment.

[0063] The inspection device 200 is a prober for inspecting an object to be inspected, such as a wafer W. A movable device 100, such as a MEMS device, is formed on the wafer W. The inspection device 200 includes a chuck 201, a tray 202, and a probe card 203, etc.

[0064] Chuck 201 is a mounting platform that holds wafer W by vacuum suction or the like. Chuck 201 is movable in the X, Y, and Z axes and rotatable around the θ axis by an alignment device located below it.

[0065] Tray 202 is placed on the top surface of chuck 201. A wafer W is placed on tray 202. Tray 202 is a dedicated tray for the movable device 100.

[0066] As shown in Figure 3, the tray 202 is provided with a recess 202A below the movable part 110 so as not to obstruct the movement of the movable part 110.

[0067] Adsorption holes (not shown) are provided at predetermined intervals around the circumferential direction of the tray 202. The outer periphery of the wafer W is adsorbed onto the tray 202 by the suction force of the chuck 201. However, the inner portion of the wafer W is not adsorbed onto the tray 202 because there are through holes 115 around the movable part 110.

[0068] The probe card 203 is equipped with multiple inspection probes 204, which are composed of probe pins and the like. The probes 204 extend downward from the bottom surface of the probe card 203. The alignment device brings the electrode portion 140 of the movable device 100 into contact with the probes 204.

[0069] The probe 204 is connected to the terminals of the test head located above the probe card 203. Power and test signals are supplied to the probe 204 from the test head. The testing device 200 measures the output signal of the movable device 100 to electrically or mechanically test whether the movable device 100 is functioning correctly.

[0070] However, since the inner portion of the wafer W is not adsorbed by the tray 202, during wafer inspection of the movable device 100, the support frame 130 of the movable device 100 also vibrates due to vibrations during operation.

[0071] Therefore, in this embodiment, the movable device 100 has a false electrode portion 150 provided on the support frame 130 surrounding the movable portion 110. During wafer inspection of the movable device 100, not only the electrode portion 140 but also the false electrode portion 150 and the probe 204 are brought into contact.

[0072] The false electrode pads 151A to 158B are positioned symmetrically with respect to the center O of the support frame 130 in a plan view. Therefore, by bringing the false electrode portion 150 into contact with the probe 204 and fixing the false electrode portion 150, the fixing of the support frame 130 during wafer inspection of the movable device 100 can be strengthened.

[0073] <Method for securing movable devices> The method for fixing the movable device 100 will be described below. Figure 4 is a diagram showing the method for fixing the movable device 100 in this embodiment. Figure 4 is a partially enlarged view of the wafer W, showing nine movable devices 100A to 100I formed on the wafer W.

[0074] The movable device 100A to be inspected is located in the center. The eight movable devices 100B to 100I surrounding the movable device 100A to be inspected are not to be inspected.

[0075] The movable devices 100B to 100I that are not subject to inspection include four movable devices labeled 100B, 100D, 100F, and 100H adjacent to the sides of the movable device 100A subject to inspection, and four movable devices labeled 100C, 100E, 100G, and 100I adjacent to the corners of the movable device 100A subject to inspection. The movable devices 100B to 100I that are not subject to inspection are movable devices provided in close proximity to the movable device 100A, and their details will be described later.

[0076] When inspecting the movable device 100A, vibration of the support frame 130A of the movable device 100A can be suppressed by bringing the electrode portion 140A and the false electrode portion 150A of the movable device 100A to contact the probe 204.

[0077] Furthermore, other false electrode portions 150B, 150C, 150D, 150E, 150F, 150G, 150H, and 150I of other non-inspection movable devices 100B to 100I surrounding the movable device 100A may be brought into contact with the probe 204. This can strengthen the fixation of the support frame 130A of the movable device 100A being inspected.

[0078] For movable devices 100B, 100D, 100F, and 100H that are not subject to inspection and are adjacent to movable device 100A in the X-axis and Y-axis directions (front-to-back and left-to-right), the support frames 130B, 130D, 130F, and 130H that constitute the adjacent sides are used.

[0079] By further bringing the false electrode sections 150B, 150D, 150F, and 150H, which are provided on the frame bodies of the support frames 130B, 130D, 130F, and 130H, into contact with the probe 204, the fixation of the support frame 130A of the movable device 100A to be inspected can be strengthened.

[0080] For the non-inspection movable devices 100C, 100E, 100G, and 100I adjacent to the upper right, lower right, upper left, and lower left of movable device 100A, the ends of the frame bodies of the support frames 130C, 130E, 130G, and 130I that constitute the adjacent corners are used.

[0081] By bringing the false electrode portions 150C, 150E, 150G, and 150I, which are provided at the ends of the support frames 130C, 130E, 130G, and 130I, into contact with the probe 204, the fixing of the support frame 130A of the movable device 100A to be inspected can be strengthened.

[0082] As described above, the flapping of the support frame 130A during the operation of the movable device 100A may be further suppressed by using the false electrode portions 150B to 150I of the non-inspection movable devices 100B to 100I that surround the movable device 100A being inspected.

[0083] <Examples> The following describes an example of inspecting the movable device 100A. Figure 5 shows the probes 204A to 204L used to inspect the movable device 100A in this embodiment.

[0084] Example 1 is a movable device 100A that was inspected using the first probe card 203A. The first probe card 203A is equipped with the first set of probes 204A and 204B.

[0085] The first pair of probes 204A and 204B make contact with the electrode portion 140 and false electrode portion 150 provided on the first frame 131A and the second frame 131B facing the first frame 131A of the movable device 100A.

[0086] One probe from the 204A contacts each of the electrode pads 141A and 142A of the first frame 131A, and one probe from the 204B contacts each of the electrode pads 141B and 142B of the second frame 131B, supplying a drive signal for the movable part to the movable device 100A.

[0087] One probe from the 204A makes contact with each of the false electrode pads 155A and 156A at the corners of the first frame 131A, and one probe from the 204B makes contact with each of the false electrode pads 155B and 156B at the corners of the second frame 131B.

[0088] One probe 204A is in contact with each of the false electrode pads 157A and 158A of the first frame 131A, and one probe 204B is in contact with each of the false electrode pads 157B and 158B of the second frame 131B.

[0089] Multiple probes of probe 204A, for example, four probes each, make contact with the false electrode pads 151A and 152A of the first frame 131A, excluding the six probes that contacted the electrode pads 141A and 142A of probe 204A and the four probes that contacted the false electrode pads 155A, 156A, 157A, and 158A. Multiple probes of probe 204B, for example, four probes each, make contact with the false electrode pads 151B and 152B of the second frame 131B, excluding the six probes that contacted the electrode pads 141B and 142B of probe 204B and the four probes that contacted the false electrode pads 155A, 156A, 157B, and 158B.

[0090] The frame bodies 131A and 131B are held down by the 12 probes 204A in contact with the false electrode pads 155A to 158A and the 12 probes 204B in contact with 155B to 158B, thereby suppressing the vibration of the movable device 100A.

[0091] In Example 1, with the movable device 100A on the wafer, the first pair of probes 204A and 204B were brought into contact with the electrode portion 140 and the false electrode portion 150 of the movable device 100A. Next, the electrical or mechanical characteristics of the movable device 100A were tested.

[0092] Example 2 uses a movable device 100A that was inspected using a second probe card 203B. The second probe card 203B further includes a second set of probes 204C and 204D in addition to the first set of probes 204A and 204B.

[0093] The second set of probes 204C and 204D make contact with the false electrode portions 150 provided on the third frame 132A of the movable device 100A and the fourth frame 132B facing the third frame 132A.

[0094] One probe 204C is in contact with each of the false electrode pads 155A at the corner of the first frame 131A, the false electrode pad 156B at the corner of the second frame 131B, that is, the false electrode pads at both corners of the third frame 132A. One probe 204D is in contact with each of the false electrode pads 156A at the corner of the first frame 131A, the false electrode pad 155B at the corner of the second frame 131B, that is, the false electrode pads at both corners of the fourth frame 132B. False electrode pads 155A, 156B, 156A, and 155B are in contact with both probes 204A and 204B, making a total of two probes in contact with each of them.

[0095] Multiple probes 204C, for example three probes each, make contact with the false electrode pads 153A and 154B of the third frame 132A, excluding the two probes that made contact with the false electrode pads 155A and 156B. Multiple probes 204D, for example three probes each, make contact with the false electrode pads 154A and 153B of the fourth frame 132B, excluding the two probes that made contact with the false electrode pads 156A and 155B.

[0096] The frames 131A and 131B are suppressed by the 12 probes 204A in contact with the false electrode pads 155A to 158A and the 12 probes 204B in contact with 155B to 158B, and further, the frames 131A, 131B, 132A, and 132B are suppressed by the 4 probes 153A, 154B, 154A, and 153B, the 6 probes 204C in contact with the false electrode pads 153A and 154B, and the 6 probes 204D in contact with the false electrode pads 154A and 153B, thereby suppressing the vibration of the movable device 100A.

[0097] In Example 2, with the movable device 100A on the wafer, the first and second sets of probes 204A, 204B, 204C, and 204D were brought into contact with the electrode portion 140 and the false electrode portion 150 of the movable device 100A. Subsequently, electrical or mechanical characteristic testing was performed on the movable device 100A.

[0098] Example 3 is a movable device 100A that was inspected using the third probe card 203C. The third probe card 203C further includes the third to sixth sets of probes 204E, 204F, 204G, 204H, 204I, 204J, 204K, and 204L, in addition to the first and second sets of probes 204A, 204B, 204C, and 204D.

[0099] The third pair of probes 204E and 204F make contact with the false electrode portions 150B and 150F provided on the non-inspection movable devices 100B and 100F, which are adjacent to the movable device 100A in the Y-axis direction (front-to-back direction).

[0100] The false electrode portion 150B, provided on the support frame 130B of the movable device 100B adjacent to the first frame 131A, and the probe 204E make contact. The contact position between the false electrode portion 150B and the probe 204E is set to be between the contact position between the probe 204A and the false electrode portion 150A.

[0101] The false electrode portion 150F, provided on the support frame 130F of the movable device 100F adjacent to the second frame 131B, and the probe 204F make contact. The contact position between the false electrode portion 150F and the probe 204F is set to be between the contact position between the probe 204B and the false electrode portion 150A.

[0102] The fourth set of probes, 204G and 204H, contact the false electrode portions 150D and 150H provided on the non-inspection movable devices 100D and 100H, which are adjacent to the movable device 100A in the X-axis direction (left-right direction).

[0103] The false electrode portion 150H, provided on the support frame 130H of the movable device 100H adjacent to the third frame 132A, and the probe 204H make contact. The contact position between the false electrode portion 150H and the probe 204H is set to be between the contact position between the probe 204D and the false electrode portion 150A.

[0104] The false electrode portion 150D, provided on the support frame 130D of the movable device 100D adjacent to the fourth frame 132B, and the probe 204G make contact. The contact position between the false electrode portion 150D and the probe 204G is positioned between the contact position between the probe 204C and the false electrode portion 150A.

[0105] The fifth set of probes 204I and 204J make contact with the false electrode portions 150C and 150G provided on the non-inspection movable devices 100C and 100G, which are adjacent to the movable device 100A in the XY positive direction (diagonal direction).

[0106] The sixth set of probes, 204K and 204L, contact the false electrode portions 150E and 150I provided on the non-inspection movable devices 100E and 100I, which are adjacent to the movable device 100A in the XY negative direction (diagonal direction).

[0107] The number of probes 204 that contact the false electrode portion 150 is not limited to the above and can be selected as appropriate. For example, although it is stated that multiple probes contact the false electrode portion 150, it is also possible to have only one probe make contact, or even more probes make contact.

[0108] In Example 3, with the movable device 100A on the wafer, the first to sixth sets of probes 204A to 204L were brought into contact with the electrode portion 140 and false electrode portion 150 of the movable device 100A and with the false electrode portion 150 of the movable devices 100B to 100I that were not to be inspected. Then, the electrical or mechanical characteristics of the movable device 100A were tested.

[0109] Furthermore, to confirm the effectiveness of wafer inspection for the movable devices 100A in Examples 1 to 3, a reference example and a comparative example were prepared.

[0110] The reference example consisted of a movable device assembled into a package without the false electrode pads 151A to 158B. In the reference example, with the movable device assembled into the package, a test socket was attached to the electrode portion 140 of the movable device, and then the electrical or mechanical characteristics of the movable device were tested.

[0111] The comparative example was a movable device without false electrode pads 151A to 158B. In the comparative example, with the movable device on the wafer, the probe 204 was brought into contact only with the electrode portion 140 of the movable device, and the electrical or mechanical characteristics of the movable device were tested.

[0112] Figure 6 shows the test results of the movable devices for the reference example, comparative example, and Examples 1 to 3. Figure 6 shows the relationship between the charge capacitance C [F] of the drive sources 122A and 122B and the frequency F [Hz] of the drive voltage applied to the drive sources 122A and 122B.

[0113] Figure 6 shows that at frequencies F where the capacitance C is large, the drive beams 121A and 121B vibrate significantly in the Z-axis direction (vertical direction).

[0114] The test results for the standard example are shown with a thick solid line. Since the test results for the standard example are those of a movable device assembled in a package, they represent the standard values.

[0115] The test results for the comparative example are shown by the dashed line. In the comparative example, the frequency FC corresponding to the peak value PC of capacitance C was far removed from the frequency F0 corresponding to the peak value P0 of capacitance C in the reference example.

[0116] Furthermore, the waveform of the comparative example's test results differed significantly from the waveform of the reference example's test results. As a result, it was found that wafer inspection of the movable device in the comparative example resulted in test results that deviated significantly from the reference values.

[0117] The test results for Example 1 are shown by the dashed line. In Example 1, the frequency F1 corresponding to the peak value P1 of the capacitance C approached the frequency F0 corresponding to the peak value P0 of the capacitance C in the reference example.

[0118] However, as indicated by the enclosed line FA, in Example 1, there was disturbance in the charge capacitance C in the high-frequency region. As a result, wafer inspection of the movable device 100A in Example 1 showed that the test results approached the reference value.

[0119] The test results for Example 2 are shown by the dashed line. In Example 2, the frequency F2 corresponding to the peak value P2 of the capacitance C came even closer to the frequency F0 corresponding to the peak value P0 of the capacitance C in the reference example.

[0120] However, as indicated by the enclosed line FA, in Example 2, there was a slight disturbance in the charge capacitance C in the high-frequency region. As a result, wafer inspection of the movable device 100A in Example 2 showed that the test results came even closer to the reference value.

[0121] The test results for Example 3 are shown by the solid line. In Example 3, the frequency F3 corresponding to the peak value P3 of the capacitance C was closest to the frequency F0 corresponding to the peak value P0 of the capacitance C in the reference example.

[0122] Furthermore, the waveform of the charge capacitance C in Example 3 was closest to the waveform of the charge capacitance C in the reference example. As a result, wafer testing of the movable device 100A in Example 3 revealed that the test results were equivalent to the reference value.

[0123] <Effects of this embodiment> The movable device 100 of this embodiment has a false electrode portion 150 on a support frame 130 that surrounds the movable portion 110 and supports the drive portion 120. The false electrode portion 150 is positioned symmetrically with respect to the center O of the support frame 130 in a plan view.

[0124] In wafer inspection of the movable device 100, it was found that the test results were close to or equivalent to the standard value. In other words, it was found that by making contact between the false electrode portion 150 and the probe 204, the fluttering of the support frame 130 caused by vibrations during the operation of the movable device 100 can be suppressed.

[0125] As a result, electrical or mechanical characteristic testing of the movable device 100 can be performed during wafer inspection, rather than after the movable device 100 has been assembled into a package. Therefore, the man-hours or number of parts required for testing the movable device 100 after assembly can be reduced.

[0126] Therefore, the movable device 100 of this embodiment provides a technology for streamlining the inspection of movable devices.

[0127] <Optical scanning device> The following describes an optical scanning device using the movable device 100. Figure 7 shows an example configuration of the optical scanning device 300 using the movable device 100.

[0128] The optical scanning device 300 is, for example, a LiDAR (Light Detection and Ranging) system. The optical scanning device 300 comprises an optical scanning control unit 310, a light source unit 320, and an optical scanning unit 330.

[0129] The optical scanning control unit 310 is a drive control device that drives and controls the light source unit 320 and the optical scanning unit 330. The optical scanning control unit 310 comprises a system controller 311, a mirror drive circuit 312, and a laser drive circuit 313.

[0130] The light source unit 320 is a light source equipped with a laser diode or the like.

[0131] The optical scanning unit 330 is an optical scanning body equipped with a movable device 100 such as a MEMS mirror. The optical scanning unit 330 comprises a mirror unit 331, a drive unit 120, a support frame 130, an electrode unit 140, and a false electrode unit 150.

[0132] The system controller 311 supplies a control signal to the mirror drive circuit 312 to control the oscillation of the mirror portion 331 of the optical scanning unit 330. The system controller 311 also supplies a laser beam irradiation timing signal to the laser drive circuit 313.

[0133] The system controller 311 includes a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). The system controller 311 also includes NVRAM (Non-Volatile Random Access Memory).

[0134] The CPU controls the entire system controller 311 and performs various arithmetic operations. ROM stores programs used to drive the CPU, such as the IPL (Initial Program Loader). RAM is used as a storage area for loading programs or as a work area for loaded programs. NVRAM stores various programs executed by the CPU.

[0135] The mirror drive circuit 312 supplies a mirror drive signal to the optical scanning unit 330 to cause the mirror unit 331 to swing around the pivot axis SA, based on a control signal from the system controller 311.

[0136] The laser drive circuit 313 supplies a laser drive signal to the light source unit 320 for driving the laser diode, based on the irradiation timing signal supplied from the system controller 311.

[0137] The light source unit 320 intermittently emits laser light at timings defined by the irradiation timing signal, based on the laser drive signal supplied from the laser drive circuit 313. The laser light emitted from the light source unit 320 is incident on the mirror unit 331 of the optical scanning unit 330.

[0138] The mirror section 331 is a mirror body that is driven by the drive unit 120 based on a mirror drive signal supplied from the mirror drive circuit 312.

[0139] The drive unit 120 is a drive source that drives the mirror unit 331 based on the mirror drive signal supplied from the mirror drive circuit 312.

[0140] The support frame 130 surrounds the mirror section 331 and supports the drive unit 120.

[0141] The electrode portion 140 is a conductor that is electrically connected to the drive unit 120. The false electrode portion 150 is a false conductor that is electrically insulated from the drive unit 120.

[0142] The electrode portion 140 and the false electrode portion 150 are provided on the support frame 130, and the false electrode portion 150 is positioned symmetrically with respect to the center of the support frame 130 in a plan view.

[0143] The optical scanning unit 330 can suppress the flapping of the support frame 130 due to vibrations during operation by bringing the false electrode portion 150 and the probe 204 into contact during wafer inspection of the movable device 100.

[0144] The electrical or mechanical characteristics of the movable device 100 can be inspected during wafer inspection, rather than in the state of the optical scanning unit 330 after the movable device 100 has been assembled into a package. Therefore, the man-hours or number of parts required for inspecting the optical scanning unit 330 after assembly can be reduced. [Explanation of Symbols]

[0145] 100, 100A, 100B, 100C, 100D, 100E, 100F, 100G, 100H, 100I...Movable device, 110...Movable part, 111...Mirror, 112...Mirror support, 113A, 113B...Twist beam, 114A, 114B...Connecting beam, 115...Through hole, 120...Drive unit, 121A, 121B...Drive beam, 122A, 122B...Drive source, 130...Support frame, 131A, 131B, 132A, 132B...Frame body, 140...Electrode part, 141A, 141B, 142A, 142B...Electrode pad, 150...False electrode part, 151A, 15 1B, 152A, 152B, 153A, 153B, 154A, 154B, 155A, 155B, 156A, 156B, 157A, 157B, 158A, 158B...False electrode pads, 200...Inspection device, 201...Chuck, 202...Tray, 202A...Recess, 203...Probe card, 204...Probe, 300...Optical scanning device, 310...Optical scanning control unit, 311...System controller, 312...Mirror drive circuit, 313...Laser drive circuit, 320...Light source unit, 330...Optical scanning unit, 331...Mirror unit, SA...Oscillating axis, W...Wafer

Claims

1. A method for inspecting a movable device, The aforementioned movable device is Movable parts and A drive unit that drives the aforementioned movable part, A support frame that surrounds the movable part and supports the drive unit, An electrode section electrically connected to the drive unit, A false electrode portion electrically insulated from the aforementioned drive unit, Equipped with, The electrode portion and the false electrode portion are provided on the support frame. Multiple false electrode portions are arranged in a plan view at positions symmetrical with respect to the center of the support frame. The plurality of false electrode portions, positioned symmetrically to the electrode portion, are brought into contact with different inspection probes, and the plurality of false electrode portions, positioned symmetrically, are fixed in contact with the inspection probes in such a manner that vibrations of the support frame during the operation of the movable device are suppressed. Inspection methods for movable devices.

2. Multiple movable devices not subject to inspection are arranged around the aforementioned movable device subject to inspection. The false electrode portion of the movable device to be inspected is provided on the support frame of the movable device to be inspected. The false electrode portion of each of the multiple movable devices not subject to inspection is provided on the support frame of each of the multiple movable devices not subject to inspection. The support frame of the movable device not subject to inspection is adjacent to the support frame of the movable device subject to inspection, The aforementioned multiple movable devices not subject to inspection include movable devices adjacent to the side of the movable device subject to inspection and movable devices adjacent to the corner of the movable device subject to inspection. The plurality of false electrode portions on the movable device to be inspected, the movable devices adjacent to the edges of the movable device to be inspected, and the movable devices adjacent to the corners of the movable device to be inspected, are each brought into contact with different inspection probes. A method for inspecting a movable device according to claim 1.

Images