MEMS element

Abstract

A microelectromechanical system (MEMS) element has a back plate (7) containing fixed electrodes (5) and a diaphragm (3) containing movable electrodes arranged opposite each other through a gasket (4) on a substrate 1 including a back chamber (9). The diaphragm (3) includes a pillar (11) connected to the back plate (7), a pillar-side slit (12), and an edge-side slit (13), forming a plurality of vibration portions (14) on the diaphragm (3). Since the central portion of the diaphragm (3) is connected to the back plate (7) by the pillar (11), the amplitude of the central portion of the diaphragm (3) can be suppressed. By providing a pillar-side slit (12) on the joint side of the pillar (11) and the diaphragm (3) and an edge-side slit (13) on the edge portion of each of the plurality of vibration portions, the difference in amplitude between the central portion and the edge portion of the diaphragm (3) is reduced.

Description

Microelectromechanical system components This disclosure relates to capacitive microelectromechanical systems (MEMS) components used as microphones, various sensors, etc. As a microelectromechanical system (MEMS) element using semiconductor manufacturing processes, a known capacitive MEMS element consists of a backplate and a diaphragm disposed on a substrate with an insulating film sandwiched between them as a spacer. The backplate includes a fixed electrode with a plurality of acoustic holes, and the diaphragm includes a movable electrode. A capacitive MEMS element is configured to detect the displacement of a movable electrode caused by the vibration of a diaphragm, as a change in capacitance between the movable and fixed electrodes, and output a detection signal. Such a MEMS element is described, for example, in Patent Document 1. [Prior Art Documents] [Patent Documents] [Patent Document 1] Japanese Patent Application Publication No. 2011-55087 [The problem that the invention aims to solve] For example, Figure 11 shows a cross-sectional schematic diagram illustrating a conventional capacitive MEMS device. As shown in Figure 11, in a conventional capacitive MEMS device, an insulating film 52 is formed on a substrate 51 serving as a support substrate, and a resonant diaphragm 53 containing conductive movable electrodes is formed on this insulating film 52. A spacer 54 made of insulating film and a backplate 57 made of conductive fixed electrodes 55 and insulating film 56 are then laminated to form an air-gap structure. 58 is an acoustic hole formed in the backplate 57, 59 is a back chamber formed in the substrate 51, and 60 is a slit formed at the edge of the resonant diaphragm 53. When sound pressure or the like is applied to the capacitive MEMS device in this way, the central portion of the resonant diaphragm 53 vibrates significantly. At this time, although the edge of the resonant diaphragm 53, which connects the substrate 51 and the spacer 54, becomes easier to vibrate by forming the slit 60, the amplitude of the edge portion is smaller compared to the amplitude of the central portion. Generally, in capacitive MEMS devices, to improve sensitivity, the spring constant of the diaphragm 53 is reduced, resulting in excessive displacement. This can cause the diaphragm 53 to contact the backplate 57, or a difference in amplitude between the central portion and the smaller edge portion of the diaphragm 53 with larger displacement. Consequently, the area of ​​the diaphragm 53 with parallel displacement to the backplate 57 decreases, leading to degradation of the acoustic overload point (AOP). However, when using this capacitive MEMS element as a microphone, it is necessary to suppress sensitivity degradation while improving AOP. Therefore, the subject of this disclosure is to provide MEMS devices with good sensitivity and improved AOP (Aspect-Oriented Programming). [Means used to solve the subject matter] An embodiment of the MEMS element disclosed herein includes: a substrate including a back chamber; a diaphragm including a movable electrode bonded to the substrate; and a backplate including a fixed electrode disposed opposite the movable electrode; wherein the diaphragm includes a pillar connecting the backplate and the diaphragm at its central portion; and a plurality of vibrating portions are included in the region between the junction of the pillar and the diaphragm and the edge portion of the diaphragm; each of the plurality of vibrating portions is formed by a region surrounded by a pillar-side slit and an edge-side slit, the pillar-side slit joining a first slit and a second slit extending from the junction of the pillar and the diaphragm toward the edge portion in mutually different directions; the edge-side slit is disposed at the edge portion between an extension line from the first slit to the edge portion and an extension line from the second slit to the edge portion. [Effects of the Invention] According to the MEMS element disclosed herein, since the central portion of the diaphragm is bonded to the backplate via pillars, the amplitude of the central portion of the diaphragm can be suppressed. Furthermore, by setting slits in the diaphragm, a vibration section with a smaller difference in amplitude is formed between the central and edge portions of the diaphragm. Forming multiple such vibration sections on the diaphragm results in a larger overall detection signal. Moreover, by dividing the diaphragm into multiple vibration sections with small areas, the force applied to each vibration section is reduced when a bias voltage is applied between the fixed and movable electrodes, thus reducing the distortion of the detection signal. Therefore, according to this disclosure, sensitivity is not reduced, providing a MEMS element that improves AOP (Aspect-Oriented Programming). As a result, a high-performance MEMS element for microphones can be obtained. The following description will illustrate embodiments of the microelectromechanical systems (MEMS) components disclosed herein with reference to the figures; however, the disclosure is not limited to these embodiments. For the purpose of illustrating Figures 1, 2, and 7-11, some dimensions have been exaggerated, and the proportions of the components or portions are not accurately shown. (Example 1) Figure 1 is a cross-sectional schematic diagram illustrating Example 1 of the Micro Electro Mechanical Systems (MEMS) device disclosed herein. As shown in Figure 1, in one embodiment of the MEMS device 100 disclosed herein, an insulating film 2, for example, made of a thermally oxidized film, is formed on a substrate 1, such as a silicon substrate. A resonant film 3 is formed on this insulating film 2 as a support substrate. The resonant film 3 includes a conductive movable electrode, for example, made of polycrystalline silicon. Furthermore, a stacked backplane 7 is provided, which includes an insulating gasket 4, for example, made of an undoped silicon glass (USG) film, a conductive fixed electrode 5, for example, made of polycrystalline silicon, and an insulating film 6, for example, made of silicon nitride. In the MEMS element of this embodiment, the diaphragm 3 and the back plate 7 are respectively bonded to the post 11 and connected, and include post-side slits 12A~12D and edge slits 13A~13D. Figure 2 is a plan view illustrating the diaphragm portion of the MEMS element shown in Figure 1, showing the arrangement of the pillar 11, pillar-side slits 12A-12D, and edge slits 13A-13D. In Figure 1, the back chamber 9 formed on the substrate 1 is circular; the outer edge of Figure 2 corresponds to the outer edge of the back chamber 9 of the substrate 1. The cross-sectional view shown in Figure 1 is a cross-sectional view through the center of the pillar 11 in Figure 2 and the two pillar-side slits 12A and 12C, or 12B and 12D, which are opposite each other with respect to the pillar 11 as the center. As shown in Figure 2, when the portion corresponding to the back chamber 9 of the diaphragm 3 is circular, a column 11 is arranged on the diaphragm 3 such that the center of the diaphragm 3 coincides with the center of the circular column 11. In the diaphragm 3, a plurality of vibration sections 14A-14D are formed in the area between the junction with the column 11 and the edge portion of the diaphragm 3. Therefore, column-side slits 12A-12D and edge slits 13A-13D are arranged around the column 11. In the embodiment shown in Figure 2, an example with four vibration sections 14A-14D is displayed. Let's take a vibrating section as an example for detailed explanation. The vibrating section 14A formed in the upper right region of the column 11 of the vibrating diaphragm 3 shown in Figure 2 has a column-side slit 12A formed by a first slit 12a and a second slit 12b. The first slit 12a extends from the column 11 upwards in the plane of the drawing parallel to the radial direction of the vibrating diaphragm 3, and the second slit 12b extends from the column 11 to the right in the plane of the drawing parallel to the radial direction of the vibrating diaphragm 3, intersecting and engaging with the first slit 12a at a 90-degree engagement angle. By forming the column-side slit 12A, a portion of the vibrating diaphragm 3 on the column side 11, which is restricted from vibration by the column 11, becomes more prone to vibration. Furthermore, by forming an edge slit 13A at the edge where the diaphragm 3 joins the substrate 1, the insulating film 2, and the gasket 4, the edge of the diaphragm 3, which is restricted from vibration due to its connection with the substrate 1, becomes more prone to vibration. Although this edge slit 13A has the same effect as the slit 60 formed in a typical MEMS element as illustrated in Figure 11, in particular, because the area enclosed by the extension lines of the extension directions of the first slit portion 12a and the second slit portion 12b shown as two dotted lines in Figure 2 is designated as a vibration portion, the edge slit 13A in this embodiment is formed to open to the position where it intersects with the aforementioned extension lines, or to the vicinity thereof. Thus, the area enclosed by the column-side slit 12A and the edge slit 13A becomes a vibrating part 14A. Similarly, the area enclosed by the column-side slit 12B and the edge slit 13B becomes a vibrating part 14B, the area enclosed by the column-side slit 12C and the edge slit 13C becomes a vibrating part 14C, and the area enclosed by the column-side slit 12D and the edge slit 13D becomes a vibrating part 14D. The plurality of vibrating parts 14A to 14D are evenly arranged around the center of the column 11 (the center of the vibrating diaphragm 3), forming four vibrating parts with uniform characteristics. Next, the vibration characteristics of the vibrating part 14A will be explained as an example. The vibration characteristics of the vibrating part 14A vary depending on the material, thickness, or size of the diaphragm 3. Furthermore, the vibration characteristics may vary depending on the shape of the column-side slit 12A and the edge slit 13A. As for the vibration characteristics of the vibrating parts 14B to 14D, since their respective shapes are the same as those of the vibrating part 14A, their vibration characteristics are the same, and therefore, explanations are omitted. Figures 3-6 illustrate the vibration characteristics of the vibrating section 14A of the MEMS element in this embodiment. The vertical axis of Figure 3 represents the amplitude, with the maximum amplitude set to 1.00, expressed as a relative quantity. The horizontal axis of Figure 3 represents the distance from the center of the diaphragm 3, and its direction is the radial direction of the diaphragm 3 from the center of the pillar 11 through the junction of the first slit portion 12a and the second slit portion 12b of the pillar-side slit 12A. The center of the pillar 11 is set to 0.00, and the outer edge shown in Figure 2 is set to 1.00, expressed as a relative distance. In Figure 3, the amplitude of the vibrating section 14A is compared when the extension length of the pillar-side slit 12A is changed to 19% (diaphragm A), 38% (diaphragm B), and 56% (diaphragm C). Here, the length from the center of the pillar 11 to the outer edge shown in Figure 2 is set to 100, and the extension length of the pillar-side slit 12A is expressed as a percentage. All conditions except for the length of the extension direction of the column-side slit 12A are set to be the same. As shown in Figure 3, it can be understood that both vibrate between the column-side slit 12A and the edge slit 13A. Furthermore, it can be understood that the longer the column-side slit 12A (slit length: vibrating membrane A < vibrating membrane B < vibrating membrane C), the greater the amplitude near the column-side slit 12A (amplitude: vibrating membrane A < vibrating membrane B < vibrating membrane C). It can also be understood that the amplitude near the edge slit 13A varies. In particular, regarding the case of diaphragm B, it can be understood that the vibrating section 14A between the column-side slit 12A and the edge slit 13A generates vibrations with almost equal amplitudes. This means that the movable electrode (diaphragm 3) of the vibrating section 14A is displaced almost parallel to the opposite fixed electrode 5. Therefore, from the perspective of improving the acoustic overload point (AOP), in this embodiment, it is preferable to set the slit length of the column-side slit 12A as diaphragm B among diaphragms A to C. The vibration characteristics of the vibrating section 14A can be adjusted not only based on the length of the column-side slit 12A as shown in Figure 3. The vibration characteristics of the vibrating section 14A can also be adjusted by changing the configuration of the column-side slit 12A. With the column-side slit 12A moving towards the edge, and setting the position from the column 11 to the corresponding outer edge as shown in Figure 2 to 100, and assuming the diaphragm D moves by a certain percentage, Figure 4 compares the amplitude of the vibrating section 14A, assuming the conditions such as the diaphragm B and slit length shown in Figure 3 are the same. As shown in Figure 4, when the column-side slit 12A moves towards the edge, it can be understood that the column-side end of the vibration area moves from the center of the diaphragm towards the edge. Therefore, the shape of the vibrating section 14A changes, and the vibration characteristics also change. At this time, the area of ​​the vibrating section 14A becomes smaller, and the relative amplitude also decreases. Here, to obtain the desired vibration characteristics, it is preferable to determine the configuration of the column-side slit 12A. Of course, even if the column-side slit 12A moves towards the center of the diaphragm 3, the shape of the vibrating part 14A changes, and the vibration characteristics also change. Furthermore, even if the arrangement of the edge slit 13A is changed, the vibration characteristics will change because the shape of the vibrating part 14A changes. Therefore, changing the shape or arrangement can achieve the desired vibration characteristics. The case of the diaphragm B will be described below. Figure 5 compares and explains the vibration characteristics of the vibrating section 14A of the MEMS element of this embodiment, including the vibrating diaphragm B, with those of a conventional example. The conventional example uses the vibrating diaphragm 53 of a generally known MEMS element with the structure shown in Figure 11. In Figure 5, the amplitudes are expressed as relative quantities, with the maximum amplitude set to 1. The distance from the center of the vibrating diaphragm is expressed as a relative distance, with the center of the diaphragm set to 0.00 and the position corresponding to the outer edge shown in Figure 2 set to 1.00. As shown in Figure 5, in a typical MEMS element, the amplitude of the diaphragm 3 is the largest at its center and decreases towards the edges. This means that the area of ​​vibration can be represented as a region at a specific distance from the center, and the periphery of the periphery does not function as a vibration unit. In contrast, in the MEMS element of this embodiment, the diaphragm in the region between the pillar-side slit 12A and the edge slit 13A vibrates more uniformly and can be understood as operating as a vibration unit (vibration unit 14A). In this embodiment, as shown in Figure 2, since it is divided into four vibration sections 14A to 14D, the signal output from each vibration section is smaller. However, as shown in Figure 5, since it includes multiple vibration sections, the area of ​​the vibration section that is almost parallel to the fixed electrode 5 in the radial direction of the vibration diaphragm 3 can be increased, and sufficiently high sensitivity can be obtained. Furthermore, Figure 6 shows the amplitude change when a sound pressure level of 130 dB is applied to the diaphragm 3. The diaphragm B in this embodiment does not differ significantly in amplitude from the diaphragm in the conventional example. However, by comparing the amplitude changes, it can be understood that the amplitude in this embodiment is symmetrical. Thus, in this embodiment of the MEMS element, where the diaphragm 3, including the movable electrode, is displaced almost parallel to the fixed electrode 5, the AOP (Average Opportunity) is improved. Moreover, if the diaphragm 3 is constructed from a material with a low spring constant that vibrates easily, when a bias voltage is applied between the fixed electrode 5 and the movable electrode, the force applied to each vibrating part is reduced, resulting in less distortion of the detection signal and improved AOP. Additionally, because the pillar 11 is included in this embodiment, even with a diaphragm 3 having a low spring constant, problems such as excessive vibration of the diaphragm 3 are avoided. Furthermore, as shown in Figure 3, the vibration characteristics of the diaphragm 3 can be appropriately modified to achieve the desired vibration characteristics. Here, the diaphragm 3 of the MEMS element disclosed herein can be configured as comprising a plurality of vibrating portions with equal vibration characteristics, or it can be configured as a combination of vibrating portions with different vibration characteristics that complement each other. In the latter case, for example, it can be configured as a combination of vibrating portions having relatively large amplitude on the column side and relatively small amplitude on the edge side, and vibrating portions having relatively small amplitude on the column side and relatively large amplitude on the edge side, thereby obtaining a detection signal. (Example 2) Next, Example 2 of the MEMS device disclosed herein will be described. Figure 7 is a plan view illustrating the diaphragm portion of the MEMS device shown in Figure 1, illustrating the arrangement of the pillar 11, the pillar-side slits 12E~12J, and the edge-side slits 13E~13J. In Figure 1, the back chamber 9 formed on the substrate 1 is circular, and the outer edge of Figure 7 corresponds to the outer edge of the back chamber 9 of the substrate 1. As shown in Figure 7, when the portion corresponding to the back chamber 9 of the diaphragm 3 is circular, a column 11 is arranged on the diaphragm 3 such that the center of the diaphragm 3 coincides with the center of the circular column 11. In the diaphragm 3, a plurality of vibration sections 14E~14J are formed in the area between the junction with the column 11 and the edge portion of the diaphragm 3. Therefore, column-side slits 12E~12J and edge slits 13E~13J are arranged around the column 11. In the embodiment shown in Figure 7, an example with six vibration sections 14E~14J is displayed. Let's take a vibrating section as an example for detailed explanation. The vibrating section 14E formed in the upper right region of the column 11 of the vibrating diaphragm 3 shown in Figure 7 has a column-side slit 12E formed by a first slit 12a and a second slit 12b. The first slit 12a extends from the column 11 upwards in the plane of the drawing parallel to the radial direction of the vibrating diaphragm 3, and the second slit 12b extends from the column 11 upwards in the plane of the drawing parallel to the radial direction of the vibrating diaphragm 3, intersecting and engaging with the first slit 12a at a 60-degree engagement angle. By forming the column-side slit 12E, a portion of the vibrating diaphragm 3 on the column side 11, which is restricted from vibration by the column 11, becomes more prone to vibration. Furthermore, by forming an edge slit 13E at the edge where the vibrating diaphragm 3 joins the substrate 1, the insulating film 2, and the gasket 4, the edge of the vibrating diaphragm 3, which is restricted from vibration due to its connection with the substrate 1, becomes more prone to vibration. Since the area enclosed by the extension lines of the first slit portion 12a and the second slit portion 12b (shown as two dotted lines in Figure 7) is defined as a vibrating portion, this edge slit 13E is formed to open to or near the positions where these extension lines intersect. Thus, the area enclosed by the column-side slit 12E and the edge slit 13E becomes a vibrating part 14E. Vibrating parts 14F to 14J are also formed in the same way. By being evenly arranged around the center of the column 11 (the center of the vibrating diaphragm 3), the plurality of vibrating parts 14E to 14J become six vibrating parts with uniform characteristics. The vibration units 14E-14J in this embodiment tend to exhibit the same vibration characteristics as the vibration units 14A-14D in Embodiment 1 described above. Specifically, the vibration characteristics of the vibration units 14E-14J vary depending on the material, thickness, or size of the diaphragm 3. Furthermore, the vibration characteristics vary depending on the shape or arrangement of the column-side slits 12E-12J and the edge-side slits 13E-13J. Therefore, the vibration sections 14E-14J of the MEMS element in this embodiment also exhibit the same vibration characteristics as those shown in Figures 3-6, similar to those in Embodiment 1. Furthermore, comparing the vibration section of this embodiment with that of Embodiment 1, the angle (joint angle) at which the first slit portion 12a and the second slit portion 12b of the column-side slits intersect is smaller in this embodiment. Here, when the extension lengths of the first slit portion 12a and the second slit portion 12b are the same, the smaller the joint angle, the smaller the column-side amplitude. Additionally, the smaller the joint angle, the shorter the length of the edge-side slit, and the smaller the amplitude on the edge side. Therefore, as explained in Figure 4 above, it is preferable to set the desired vibration characteristics by appropriately setting the length of the column-side slits 12E-12J. Thus, in this embodiment, the amplitude of the vibrating diaphragm 3 can be made almost uniform in the region between the column-side slits 12E~12J and their respective edge-side slits 13E~13J. This is because the vibrating diaphragm 3 containing the movable electrode in the vibrating section 14E~14J is displaced almost parallel to the opposite fixed electrode 5. In this embodiment, as shown in Figure 7, since it is divided into six vibration sections 14E~14J, the signal output from each vibration section is smaller. However, since it includes multiple vibration sections, the area of ​​the vibration section that can be displaced almost parallel to the fixed electrode 5 in the radial direction of the vibration diaphragm 3 can be increased, and sufficiently high sensitivity can be obtained. Furthermore, since the vibrating diaphragm 3, which includes the movable electrode, is displaced almost parallel to the fixed electrode 5, the AOP (Average Opportunity) can be improved. Moreover, if a vibrating diaphragm 3 with a small spring constant is used, the force applied to each vibrating part can be reduced when a bias voltage is applied between the fixed electrode 5 and the movable electrode of the vibrating part, resulting in less distortion of the detection signal and improved AOP. In this embodiment, because the pillar 11 is included, even with a vibrating diaphragm 3 having a small spring constant, problems such as excessive vibration of the vibrating diaphragm 3 will not occur. Furthermore, it can be configured to include a plurality of vibrating parts with equal vibration characteristics, or it can be configured to combine vibrating parts with different vibration characteristics to complement each other. (Example 3) Next, Example 3 of the MEMS device disclosed herein will be described. Figure 8 is a plan view illustrating the diaphragm portion of the MEMS device shown in Figure 1, illustrating the arrangement of the pillar 11, pillar-side slits 12K~12N, and edge-side slits 13K~13N. In Figure 1, the back chamber 9 formed on the substrate 1 is circular, and the outer edge of Figure 8 corresponds to the outer edge of the back chamber 9 of the substrate 1. In the MEMS device of this embodiment shown in Figure 8, the shape of the edge-side slits 13K~13N is different from that of the MEMS device described in Example 1 above shown in Figure 2. Taking a vibrating section as an example, the vibrating section 14K formed in the upper right region of the pillar 11 of the vibrating diaphragm 3 shown in Figure 8 has a pillar-side slit 12K formed by a first slit portion 12a and a second slit portion 12b. The pillar-side slit 12K corresponds to the pillar-side slit 12A shown in Figure 2. In addition, an edge-side slit 13K formed by a third slit portion 13a and a fourth slit portion 13b is formed. The third slit portion 13a corresponds to the edge-side slit 13A shown in Figure 2. In this embodiment, the fourth slit portion 13b is arranged on the pillar 11 side of the third slit portion 13a, and the edge-side slit 13K is formed by the third slit portion 13a and the fourth slit portion 13b. Because the area enclosed by the extension lines of the first slit portion 12a and the second slit portion 12b shown as two dashed lines in Figure 8 is designated as a vibrating portion, the edge slits 13K formed by the third slit portion 13a and the fourth slit portion 13b are formed to open to or near the positions where they intersect the aforementioned extension lines. By adding this fourth slit portion 13b, compared to the case where only the edge slits 13A to 13D formed by the third slit portion 13a shown in Figure 2 are included, the edge of the vibrating diaphragm 3 becomes easier to vibrate. Thus, the area enclosed by the column-side slit 12K and the edge slit 13K becomes a vibrating part 14K. Vibrating parts 14L to 14N are also formed in the same way. By being evenly arranged around the center of the column 11 (the center of the vibrating diaphragm 3), the plurality of vibrating parts 14K to 14N become four vibrating parts 14K to 14N with uniform characteristics. In this embodiment, the material, thickness, size, shape or configuration of the column-side slits 12K~12N and the edge-side slits 13K~13N constituting the vibrating diaphragm 3 can also be appropriately set so that the vibrating part 14K~14N has the desired vibration characteristics. Furthermore, although this embodiment is described using a MEMS element with four 14K~14N vibration sections as an example, a MEMS element with six vibration sections can also be applied as shown in Embodiment 2 above. Since the length of the edge slits decreases as the number of vibration sections increases, the amplitude of the vibration at the edge of the vibrating diaphragm 3 will decrease. In order to increase the amplitude at the edge, it is preferable to modify the amplitude at the edge to the desired vibration characteristics by including a fourth slit. Thus, in this embodiment, the amplitude of the vibrating diaphragm 3 can be made almost uniform in the region between the column-side slits 12K~12N and their respective edge-side slits 13K~13N. In this embodiment, because it is divided into multiple vibration sections, the signal output from each vibration section 14K to 14N is smaller. However, since it includes multiple vibration sections 14K to 14N, the area of ​​the vibration section that can be displaced almost parallel to the fixed electrode 5 in the radial direction of the vibration diaphragm 3 can be increased, and sufficiently high sensitivity can be obtained. In particular, in this embodiment, since the amplitude of the vibration at the edge of the vibration diaphragm 3 is increased, higher sensitivity than that of the MEMS element described in the first embodiment above can be obtained. Furthermore, since the vibrating diaphragm 3, which includes the movable electrode, is displaced almost parallel to the fixed electrode 5, the AOP (Average Opportunity) is improved. Moreover, if a vibrating diaphragm 3 with a small spring constant is used, the force applied to each vibrating part can be reduced when a bias voltage is applied between the fixed electrode 5 and the movable electrode of the vibrating part, resulting in less distortion of the detection signal and improved AOP. In this embodiment, because the pillar 11 is included, even with a vibrating diaphragm 3 having a small spring constant, problems such as excessive vibration of the vibrating diaphragm 3 are avoided. Furthermore, it can be configured to include vibrational parts with equal vibrational characteristics, or it can be configured to combine vibrational parts with different vibrational characteristics to complement each other. (Example 4) Next, Example 4 of the MEMS element disclosed herein will be described. In Examples 1 to 3 above, the edge slit 13 is a through hole of the diaphragm 3. In contrast, the edge slits 13P to 13S of this embodiment, as shown in Figure 9, differ in that they have an open end formed on the diaphragm 3 and an opening opposite to this open end. Figure 9 is a cross-sectional schematic diagram for illustrating Example 4 of the MEMS element disclosed herein. Figure 10 is a plan view for illustrating the diaphragm portion of the MEMS element shown in Figure 9, and is a plan view viewed from the backplate 7 side excluding the backplate 7. Compared with the MEMS element 100 shown in Figure 1 described in Example 1 above, the MEMS element 200 according to this embodiment has a different support structure for the diaphragm 3 including the movable electrode, and one end of a portion of the diaphragm 3 is an open end. In the MEMS element of this embodiment, the end of the diaphragm 3 facing the substrate 1, insulating film 2, or gasket 4 is an open end, and the non-open end of the diaphragm 3 is a support portion 15. The cross-sectional view shown in Figure 9 is a cross-sectional view through the center of the pillar 11 in Figure 10 and the two pillar-side slits 12P and 12R, or 12Q and 12S, which are opposite each other with the pillar 11 as the center. Therefore, the support portion 15 of the diaphragm 3 is not shown in Figure 9. The support portion 15 of the diaphragm 3 is laminated on the insulating film 2 in the unshown area, forming a structure in which the gasket 4 is laminated on this support portion 15. In the MEMS element of this embodiment, the end of the diaphragm 3 is called an open end. Specifically, the gap between the open end and the gasket 4 is called an edge slit 13P~13S. These edge slits 13P~13S correspond to the edge slits 13A~13N described in embodiments 1~3 above. However, as shown in Figure 10, when the portion corresponding to the back chamber 9 of the diaphragm 3 is circular, a column 11 is arranged on the diaphragm 3 such that the center of the diaphragm 3 coincides with the center of the circular column 11. In the diaphragm 3, a plurality of vibration sections 14P~14S are formed in the area between the joint with the column 11 and the open end of the diaphragm 3. Therefore, the column-side slits 12P~12S and the edge slits 13P~13S are arranged around the column 11. In the embodiment shown in Figure 10, an example of forming four vibration sections 14P~14S is shown. Let's take a vibrating section as an example for detailed explanation. The vibrating section 14P formed in the upper right region of the column 11 of the vibrating diaphragm 3 shown in Figure 10 has a column-side slit 12P formed by a first slit 12a and a second slit 12b. The first slit 12a extends from the column 11 side upwards in the plane of the drawing parallel to the radial direction of the vibrating diaphragm 3, and the second slit 12b extends from the column 11 side to the right in the plane of the drawing parallel to the radial direction of the vibrating diaphragm 3, intersecting and engaging with the first slit 12a at a 90-degree engagement angle. By forming the column-side slit 12P, a portion of the vibrating diaphragm 3 on the column side 11, which is restricted from vibration by the column 11, becomes more prone to vibration. Since the area enclosed by the extension lines of the first slit portion 12a and the second slit portion 12b shown as two dotted lines in Figure 10 is designated as a vibrating portion, the edge slits 13P formed by the open end of the vibrating diaphragm 3 are formed to open to the position intersecting with the aforementioned extension lines, or to the vicinity thereof. Thus, the area enclosed by the column-side slit 12P and the edge slit 13P becomes a vibrating part 14P. Vibrating parts 14P to 14S are also formed in the same way. By being evenly arranged around the center of the column 11 (the center of the vibrating diaphragm 3), the plurality of vibrating parts 14P to 14S become four vibrating parts with uniform characteristics. The vibration units 14P-14S in this embodiment tend to exhibit the same vibration characteristics as the vibration units 14A-14D in Embodiment 1 described above. Specifically, the vibration characteristics of the vibration units 14P-14S vary depending on the material, thickness, or size of the diaphragm 3. Furthermore, the vibration characteristics vary depending on the shape or arrangement of the column-side slits 12P-12S. Therefore, the vibration sections 14P to 14S of the MEMS element in this embodiment also exhibit the same vibration characteristics as those shown in Figures 3 to 6, similar to those in Embodiment 1. Furthermore, comparing the vibration section of this embodiment with that of Embodiment 1, the area where the vibration diaphragm 3 is bonded to the substrate 1 in this embodiment is smaller, making it less susceptible to deformation of the substrate 1. Thus, in this embodiment, the amplitude of the vibrating diaphragm 3 can be made almost uniform in the region between the column-side slits 12P~12S and their respective edge-side slits 13P~13S. This is because the vibrating diaphragm 3 containing the movable electrode in the vibrating section 14P~14S is displaced almost parallel to the opposite fixed electrode 5. In this embodiment, as shown in Figure 10, since it is divided into four vibration sections 14P~14S, the signal output from each vibration section is smaller. However, since it includes multiple vibration sections, the area of ​​the vibration section that is almost parallel to the fixed electrode 5 in the radial direction of the vibration diaphragm 3 can be increased, and sufficiently high sensitivity can be obtained. Furthermore, since the vibrating diaphragm 3, which includes the movable electrode, is displaced almost parallel to the fixed electrode 5, the AOP (Average Opportunity) can be improved. Moreover, if a vibrating diaphragm 3 with a small spring constant is used, the force applied to each vibrating part can be reduced when a bias voltage is applied between the fixed electrode 5 and the movable electrode of the vibrating part, resulting in less distortion of the detection signal and improved AOP. In this embodiment, because the pillar 11 is included, even with a vibrating diaphragm 3 having a small spring constant, problems such as excessive vibration of the vibrating diaphragm 3 will not occur. Furthermore, although this embodiment is described using a MEMS element comprising four vibration sections 14P~14S as an example, a MEMS element comprising six vibration sections can also be applied as shown in Embodiment 2 above. In this case, the number of support sections 15 can be set to six. In addition, since the amplitude near the support section 15 increases, by configuring the edge slits 13P~13S to each include a fourth slit section 13b as described in Embodiment 3 above, the amplitude of the edge portion near the support section 15 of the vibrating diaphragm 3 can be changed to achieve the desired vibration characteristics. Alternatively, it can be configured to include vibrational parts with equal vibrational characteristics, or it can be configured to combine vibrational parts with different vibrational characteristics to complement each other. (Summary) (1) An embodiment of the microelectromechanical system (MEMS) element disclosed herein includes: a substrate including a back chamber; a diaphragm including a movable electrode bonded to the substrate; and a back plate including a fixed electrode disposed opposite the movable electrode; wherein the diaphragm includes a pillar connecting the back plate and the diaphragm at its central portion; and a plurality of vibrating portions are included in the region between the junction of the pillar and the diaphragm and the edge portion of the diaphragm; each of the plurality of vibrating portions is formed by a region surrounded by a pillar-side slit and an edge-side slit, the pillar-side slit joining a first slit and a second slit extending from the junction of the pillar and the diaphragm toward the edge portion in mutually different directions; the edge-side slit is disposed at the edge portion between an extension line from the first slit portion toward the edge portion and an extension line from the second slit portion toward the edge portion. According to the MEMS element of this embodiment, by using pillars disposed at the center of the diaphragm and joined to the backplate, the amplitude at the center of the diaphragm is suppressed. Furthermore, by providing pillar-side slits and edge-side slits on the diaphragm, a vibration section with a small difference in amplitude between the center and the edge of the diaphragm can be formed. By forming a plurality of such vibration sections, a larger overall detection signal can be obtained. Moreover, by increasing the amplitude of the vibration section and dividing it into a plurality of vibration sections, when a bias voltage is applied between the fixed electrode and the movable electrode of the vibration section, the force applied to each vibration section can be reduced, and the distortion of the detection signal can be reduced. (2) By setting the column-side slit as an opening that penetrates the diaphragm, and setting the edge-side slit as an opening that penetrates the diaphragm or an opening between the open end of the diaphragm and the opposite side of the open end, the vibration characteristics of the diaphragm can be easily changed. (3) The edge side slit can be configured to include a third slit portion formed along the inner side of the edge of the vibrating diaphragm, and a fourth slit portion formed along the third slit portion on the column side of the third slit portion. By adding the fourth slit portion, the edge of the vibrating diaphragm can be made to vibrate easily. (4) The above-mentioned multiple vibration units can be set as vibration units with the same vibration characteristics, thereby obtaining a larger detection signal. (5) By configuring the above-mentioned multiple vibration units to include at least two vibration units with different vibration characteristics, the vibration characteristics of the central part or the edge part of the diaphragm can be changed respectively, and a vibration unit with a smaller difference in amplitude between the central part and the edge part of the diaphragm can be formed, thereby obtaining a larger detection signal. (6) By configuring the above-mentioned multiple vibrating parts to have the same shape of the above-mentioned column-side slits and the above-mentioned edge-side slits, a larger detection signal can be obtained. (7) By configuring the above-mentioned plurality of vibration parts to include at least two vibration parts, wherein the two vibration parts have at least one of the above-mentioned column side slits or the above-mentioned edge side slits with different shapes, the vibration characteristics of the central part or the edge part of the diaphragm can be changed respectively, and a vibration part with a smaller difference in amplitude between the central part and the edge part of the diaphragm can be formed, thereby obtaining a larger detection signal. (8) By forming the first slit portion and the second slit portion constituting the column side slit with a length and / or engagement angle that can obtain specific vibration characteristics, the vibration characteristics of the central portion of the diaphragm can be changed, and a vibration portion with a smaller difference in amplitude between the central portion and the edge portion of the diaphragm can be formed, thereby obtaining a larger detection signal. 100, 200: MEMS Components 1: Substrate 2: Insulating Film 3: Vibrating Diaphragm 4: Gasket 5: Fixed Electrode 6: Insulating Film 7: Backplate 8: Acoustic Hole 9: Back Chamber 11: Column 12, 12A~12N, 12P~12S: Column Side Slits 13, 13A~13N, 13P~13S: Edge Slits 14, 14A~14N, 14P~14S: Vibrating Part 15: Support Part 12a: First Slit 12b: Second Slit 13a: Third Slit 13b: Fourth Slit A, B, C, D: Vibrating Diaphragm [Figure 1] is a cross-sectional schematic diagram of a microelectromechanical system (MEMS) element (Embodiment 1) according to one embodiment of this disclosure. [Figure 2] is a plan view illustrating the diaphragm portion in Embodiment 1. [Figure 3] is a diagram illustrating the vibration characteristics of the vibrating part in Embodiment 1. [Figure 4] is a diagram illustrating the vibration characteristics of the vibrating part in Embodiment 1. [Figure 5] is a diagram illustrating the vibration characteristics of the vibrating part in Embodiment 1. [Figure 6] is a diagram illustrating the vibration characteristics of the vibrating part in Embodiment 1. [Figure 7] is a plan view of the diaphragm portion in a MEMS element (Embodiment 2) according to another embodiment of this disclosure. [Figure 8] is a plan view of the diaphragm portion in a MEMS element (Embodiment 3) according to another embodiment of this disclosure. [Figure 9] is a cross-sectional schematic diagram of a MEMS element (Embodiment 4) according to another embodiment of this disclosure. [Figure 10] is a plan view illustrating the diaphragm portion in Embodiment 4. [Figure 11] is a cross-sectional schematic diagram of a conventional capacitive MEMS device. 100: MEMS components 1:Substrate 2: Insulating film 3: Vibrating diaphragm 4: Gasket 5: Fixed electrode 6: Insulating film 7: Back panel 8: Sound hole 9: Back Chamber 11: column 12: Column side slit 13: Edge slit 14: Vibrating section

Claims

1. A microelectromechanical system (MEMS) component, comprising: The substrate includes a back chamber; A vibrating diaphragm, comprising movable electrodes bonded to the aforementioned substrate; The backplate includes a fixed electrode disposed opposite the movable electrode; wherein the diaphragm includes a pillar connecting the backplate and the diaphragm at its central portion; and a plurality of vibrating portions are included in the region between the junction of the pillar and the diaphragm and the edge of the diaphragm; each of the plurality of vibrating portions is formed by a region surrounded by a pillar-side slit and an edge-side slit, the pillar-side slit joining a first slit and a second slit extending from the junction of the pillar and the diaphragm toward the edge in mutually different directions; the edge-side slit is disposed at the edge between the extension line from the first slit to the edge and the extension line from the second slit to the edge.

2. The microelectromechanical system component of claim 1, wherein the aforementioned column-side slit is formed by an opening penetrating the aforementioned diaphragm, and the aforementioned edge-side slit is formed by an opening penetrating the aforementioned diaphragm or an opening between the open end of the aforementioned diaphragm and the opposite side of the aforementioned open end.

3. The microelectromechanical system component of claim 1, wherein the aforementioned edge-side slit includes a third slit portion formed along the inner side of the edge portion of the aforementioned vibrating diaphragm, and a fourth slit portion formed along the aforementioned third slit portion on the aforementioned column side of the aforementioned third slit portion.

4. The microelectromechanical system component as claimed in any of claims 1 to 3, wherein the aforementioned plurality of vibrating parts are vibrating parts that each have the same vibration characteristics.

5. A microelectromechanical system component as claimed in any one of claims 1 to 3, wherein the aforementioned plurality of vibrating parts includes at least two vibrating parts having different vibration characteristics.

6. The microelectromechanical system element of any one of claims 1 to 3, wherein the aforementioned plurality of vibrating parts all have the aforementioned column-side slits of the same shape and the aforementioned edge-side slits of the same shape.

7. A microelectromechanical system component as claimed in any one of claims 1 to 3, wherein the aforementioned plurality of vibrating parts includes at least two vibrating parts, and the aforementioned two vibrating parts have at least one of the aforementioned column-side slits or the aforementioned edge-side slits with different shapes.

8. The microelectromechanical system element of any one of claims 1 to 3, wherein the first slit portion and the second slit portion constituting the aforementioned column-side slit are formed by a length and / or engagement angle that can obtain specific vibration characteristics.

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