Detailed Description
The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments.
The existing acceleration sensor has two types, one type is that three relatively independent mass blocks are arranged, the three mass blocks are respectively used for measuring acceleration in three directions, and the acceleration sensor can reduce cross coupling, but has the problems of large chip area and high cost; another is to provide a mass block for measuring acceleration in three directions simultaneously, and this acceleration sensor has a problem of inaccurate measurement results due to cross coupling although it can reduce the cost.
In addition, for an acceleration sensor that measures acceleration in three directions based on one mass, in order to measure acceleration in the X direction, a spring beam extending in the Y direction needs to be provided on the mass so that at least a part of the mass can translate in the X direction; similarly, to measure acceleration in the Y direction, the mass needs to be provided with spring beams extending in the X direction so that at least a portion of the mass can translate in the Y direction. That is, the mass block of the acceleration sensor has at least two spring beams extending in two directions, and the arrangement of the spring beams extending in two directions makes the area of the whole chip larger. Therefore, the acceleration sensor based on the same mass block for measuring acceleration in three directions still has the problem of larger chip area in the prior art.
Fig. 1 is a schematic structural diagram of an acceleration sensor 100 according to an embodiment of the application. Referring to fig. 1 and 2, the acceleration sensor 100 includes: a substrate 110 and a mass 120.
The mass 120 comprises a first region 121 and a second region 122, the mass 120 being movably connected to the substrate 110 such that the acceleration sensor 100 detects an acceleration in an X-direction, which is in a plane, when the first region 121 and the second region 122 are twisted about a Z-axis perpendicular to the plane in which the mass 120 lies.
The three-dimensional rectangular coordinate system in fig. 1 shows X, Y and the Z direction. Referring to fig. 1, when there is acceleration in the X positive direction (the direction indicated by the X arrow in fig. 1), the first region 121 may twist right, and the second region 122 may twist left. For example, twisting of the first and second regions 121, 122 may be seen as a clockwise rotation of the first and second regions 121, 122 about a point therebetween.
Similarly, when there is acceleration in the negative X direction, the first region 121 may twist left and the second region 122 twist right. For example, twisting of the first and second regions 121, 122 may be seen as counterclockwise rotation of the first and second regions 121, 122 about a point therebetween.
In one embodiment, the first region 121 may form a capacitance with a fixed electrode on the substrate 110. When the first region 121 is twisted left or right, the capacitance value of the capacitor may be changed, and the magnitude and direction of the acceleration in the X direction may be detected according to the changed capacitance value.
By detecting acceleration in the X direction by twisting the first region 121 to the left or right, it is possible to avoid providing a spring beam extending in the Y direction at the periphery of the first region 121, and thus it is possible to significantly reduce the size of the mass block 120 and the chip area, thereby achieving miniaturization of the acceleration sensor.
Further, the second region 122 may also form a capacitance with a fixed electrode on the substrate 110. When the second region 122 is twisted left or right, the capacitance value of the capacitor changes. The accuracy of the acceleration detection result in the X direction can be improved in combination with the capacitance value change corresponding to the first region 121 and the capacitance value change corresponding to the second region 122.
In other embodiments, the acceleration sensor 100 may also be used to detect acceleration in the Y direction. Or the acceleration sensor 100 may be used to detect X, Y as well as acceleration in the Z direction.
The embodiment of the application provides an acceleration sensor, which can remarkably reduce the size of a mass block and the area of a chip by arranging the mass block into a first area and a second area which can mutually twist around a Z axis perpendicular to the plane of the mass block and detecting the acceleration in the X direction based on the mutual twisting of the first area and the second area, thereby realizing the miniaturization of the acceleration sensor.
According to an embodiment of the present application, the mass 120 is provided with a first spring beam 123 extending in the X direction, the first spring beam 123 being located between the first region 121 and the second region 122, and the first region 121 and the second region 122 being connected to each other through a middle portion of the first spring beam 123.
Specifically, the first region 121 and the second region 122 are connected by a first spring beam 123. As shown in fig. 1, the first spring beam 123 extends in the X direction, and the first region 121 and the second region 122 are distributed on both upper and lower sides of the first spring beam 123. The first region 121 and the second region 122 may be connected to the middle portion (one half of the length) of the first spring beam 123, so that the entire structure is more balanced, and the accuracy of the detection result is improved.
Of course, the first area 121 and the second area 122 may also be connected to other portions (such as a third, a quarter, etc. of the length) of the first spring beam 123, as long as the first area 121 and the second area 122 can be ensured to be balanced with each other, which is not limited by the embodiment of the present application.
In one embodiment, the first region 121 and the second region 122 are of unequal mass. For example, the mass of the first region 121 is greater than the mass of the second region 122. Thus, when there is acceleration in the X direction, the first region 121 may twist right (or left) and the second region 122 may twist left (or right) because the first spring beam 123 may be elastically deformed. Here, although the mass of the first region 121 is greater than the mass of the second region 122, the difference between the masses can be within the stiffness range of the mass block 120, that is, the relative balance between the first region 121 and the second region 122 can be maintained, because the displacement variation caused by the mass imbalance is about one thousandth of the original pitch under the influence of the gravitational acceleration, which is very weak displacement for the device, and does not cause unbalance of the device.
In other embodiments, the mutual twisting between the first region 121 and the second region 122 may be achieved by other suitable means, for example, a fixed point between the first region 121 and the second region 122 and the two is elastically connected to achieve the mutual twisting therebetween. The connection manner between the first region 121 and the second region 122 is not limited in the embodiment of the present application.
According to an embodiment of the present application, the distance from the center of gravity of the first region 121 to the first spring beam 123 is greater than the distance from the center of gravity of the second region 122 to the first spring beam 123.
Specifically, to achieve mutual twisting of the first region 121 and the second region 122, the size of the first region 121 is larger than the size of the second region 122. As shown in fig. 1, the first region 121 and the second region 122 have equal lengths in the X direction, and the width of the first region 121 in the Y direction is greater than the width of the second region 122 in the Y direction.
In another embodiment, the widths of the first region 121 and the second region 122 in the Y direction are equal, and the length of the first region 121 in the X direction is greater than the length of the second region 122 in the X direction. At this time, the distance from the center of gravity of the first region 121 to the first spring beam 123 is equal to the distance from the center of gravity of the second region 122 to the first spring beam 123. However, since the mass of the first region 121 is still greater than the mass of the second region 122, the first region 121 and the second region 122 can still twist with each other when there is acceleration in the X direction.
According to an embodiment of the present application, the mass 120 is provided with a second spring beam 124 and a third spring beam 125 extending in the X direction, the second spring beam 124 is located outside the first region 121, the third spring beam 125 is located outside the second region 122, and the acceleration sensor detects the acceleration in the Y direction when the first region 121 and the second region 122 move in the Y direction.
Specifically, as shown in fig. 1, the first region 121 and the second region 122 can be regarded as a complete movable region, and the second spring beam 124 and the third spring beam 125 are located on opposite sides of the complete movable region, respectively, and extend in the X direction. Thus, when acceleration exists in the Y direction, the complete movable region can translate along the Y direction, so that the capacitance for detecting the acceleration in the Y direction is changed, and the magnitude and the direction of the acceleration in the Y direction are detected. Here, the capacitance for detecting acceleration in the Y direction may be formed by the entire movable region and the fixed electrode on the substrate 110.
In one embodiment, the mass 120 is provided with a first spring beam 123, a second spring beam 124 and a third spring beam 125, which all extend in the X direction. As shown in fig. 1, the first spring beam 123 is located between the first region 121 and the second region 122, so that the first region 121 and the second region 122 can be twisted with each other, and further, the acceleration in the X direction can be detected. The second spring beam 124 is located outside the first region 121, and the third spring beam 125 is located outside the second region 122, and these two spring beams can implement translation of the first region 121 and the second region 122 in the Y direction, so that detection of acceleration in the Y direction can be implemented. The acceleration in the X and Y directions is detected by arranging the three spring beams extending in the same direction, so that the high-efficiency utilization of the area of the mass block can be realized, the area of a chip is obviously reduced, and the miniaturization of the acceleration sensor is realized.
According to an embodiment of the present application, the substrate 110 is provided with a first fixing point 131 and a second fixing point 132, the first fixing point 131 is connected to the second spring beam 124, and the second fixing point 132 is connected to the third spring beam 125.
In particular, the movable connection between the mass 120 and the substrate 110 is achieved by the cooperation of a fixed point and a spring beam. As shown in fig. 1, the second spring beam 124 is connected to a first fixed point 131 and the third spring beam 125 is connected to a second fixed point 132, thereby achieving a connection between the mass 120 and the substrate 110.
In this embodiment, the spring beams are disposed at opposite ends of the mass block 120, and the fixing points are disposed at positions on the substrate 110 corresponding to the two spring beams, so that a situation that a fixing point (or referred to as an anchor point) is disposed at a middle position of the mass block in the prior art can be avoided, and thus stress concentration can be avoided, and the service life of the acceleration sensor can be prolonged.
In one embodiment, as shown in FIG. 1, the mass 120 includes a first region 121, a second region 122, and a frame 126, the first region 121 and the second region 122 being located in the frame 126. The mass 120 further includes a first spring beam 123 located between the first region 121 and the second region 122, a second spring beam 124 located between the first region 121 and the frame 126, and a third spring beam 125 located between the second region 122 and the frame 126. The first spring beam 123, the second spring beam 124, and the third spring beam 125 each extend in the X direction. The first and second regions 121 and 122 are connected to the frame 126 by first spring beams 123, for example, both ends of the first spring beams 123 are connected to the frame 126. The second and third spring beams 124 and 125 are connected to first and second fixed points 131 and 132, respectively, on the substrate 110 to achieve a movable connection between the mass 120 and the substrate 110.
According to an embodiment of the present application, the first movable electrode 141 and the second movable electrode 142 are disposed on the first region 121, the first fixed electrode 151 and the second fixed electrode 152 are disposed on the substrate 110, the first movable electrode 141 and the first fixed electrode 151 form a first capacitor, the second movable electrode 142 and the second fixed electrode 152 form a second capacitor, a capacitance change direction of the first capacitor is opposite to a capacitance change direction of the second capacitor, and the first capacitor and the second capacitor are used for detecting acceleration in the X direction.
Specifically, the first and second movable electrodes 141 and 142 may be comb-teeth electrodes, which may be provided on the first region 121 by etching or the like. The first and second fixed electrodes 151 and 152 may be comb-tooth electrodes, and the shapes of the first and second fixed electrodes 151 and 152 correspond to the shapes of the first and second movable electrodes 141 and 142, respectively. As shown in fig. 1, the first movable electrode 141 forms a hollowed pattern in the first region 121, the first fixed electrode 151 is located in the hollowed pattern, and the comb teeth of the first fixed electrode 151 are arranged to cross the comb teeth of the first movable electrode 141. Similarly, the second fixed electrode 152 is located in the hollowed pattern formed by the second movable electrode 142, and the comb teeth of the second fixed electrode 152 are arranged to cross the comb teeth of the second movable electrode 142.
As shown in fig. 1, when the first region 121 is twisted rightward, the distance between the comb teeth 1 of the first fixed electrode 151 and the comb teeth 2 of the first movable electrode 141 or the side wall 2 '(the side wall 2' can be regarded as a part of the first movable electrode 141) in the first region 121 becomes large, so that the capacitance value of the first capacitor becomes small, and the capacitance change amount of the first capacitor is denoted as Δcx1. Further, the distance between the comb teeth 3 of the second fixed electrode 152 and the comb teeth 4 of the second movable electrode 142 or the side wall 4 '(the side wall 4' can be regarded as a part of the second movable electrode 142) in the first region 121 becomes small, so that the capacitance value of the second capacitance becomes large, where the capacitance variation amount of the second capacitance is denoted as Δcx2. Both Δcx1 and Δcx2 have the same magnitude and opposite direction of change. In this embodiment, the acceleration in the X direction may be obtained based on the difference between Δcx1 and Δcx2, so that the amounts of change in the two directions may be combined, and the accuracy and reliability of the detection result may be improved.
In the present embodiment, the more the number of the comb teeth of the first and second movable electrodes 141 and 142, the more accurate the detection result, but the too many comb teeth may cause an excessively large chip area, therefore, the number of the comb teeth of the first and second movable electrodes 141 and 142 may be set according to actual needs, which is not limited in the embodiment of the present application.
In another embodiment, the movable electrode may be provided on the second region 122 instead of the first region 121 to realize detection of acceleration in the X direction.
According to an embodiment of the present application, at least one hollow area is disposed on the first area 121, at least one third fixed electrode 153 is disposed on the substrate 110 in each hollow area 143 of the at least one hollow area, and the sidewall 5 of the hollow area 143 and the at least one third fixed electrode 153 form a third capacitor, and the third capacitor is used for detecting acceleration in the Y direction.
Specifically, as shown in fig. 1, when there is an acceleration in the Y positive direction (the direction indicated by the Y arrow in fig. 1), the first region 121 and the second region 122 move upward together, and at this time, the distance between the third fixed electrode 153 and the sidewall 5 of the hollowed-out region 143 becomes smaller, so that the capacitance value of the third capacitor becomes larger, where the capacitance change amount of the third capacitor is denoted as Δcy1. Acceleration in the Y direction can be acquired based on Δcy1.
In an embodiment, the number of the third fixing electrodes 153 in each hollow area 143 may be plural, and the plurality of the third fixing electrodes 153 may be aligned (i.e. aligned along the X direction) and disposed close to the sidewall 5.
In another embodiment, a plurality of hollow areas 143 may be disposed on the first area 121, and a third fixed electrode 153 adjacent to the sidewall 5 is disposed in each hollow area 143. Through the plurality of hollowed-out areas 143 and the corresponding plurality of third fixed electrodes 153, a plurality of deltacy 1 can be obtained, and the acceleration in the Y direction can be obtained based on the average value of the plurality of deltacy 1, so that the accuracy of the detection result can be improved.
In an embodiment, the first movable electrode 141 and the second movable electrode 142 are located at both ends of the first region 121, that is, the first movable electrode 141 is near one end of the first spring beam 123 and the second movable electrode 142 is near the other end of the first spring beam 123. This facilitates the first and second movable electrodes 141 and 142 to twist as much as possible based on the acceleration in the X direction, and improves the sensitivity of the first and second capacitances. The hollowed-out area 143 may be located between the first movable electrode 141 and the second movable electrode 142.
According to an embodiment of the present application, as shown in fig. 2, a fourth fixed electrode 154 is disposed on the substrate 110, and a fourth capacitance is formed between the fourth fixed electrode 154 and the first region 121, and is used to detect acceleration in the Z direction when the first region 121 and the second region 122 rotate around the first spring beam 123.
In particular, referring to fig. 1 and 2, the fourth fixed electrode 154 may be positioned between the first fixed electrode 151 and the second fixed electrode 152. A fourth capacitance may be formed between the fourth fixed electrode 154 and the first region 121. Referring to fig. 1 and 2, when there is an acceleration in the Z positive direction (the direction indicated by the Z arrow in fig. 1, i.e., the direction out of the plane of the paper), the first region 121 rotates in the Z positive direction, and the distance between it and the fourth fixed electrode 154 becomes large, so that the capacitance value of the fourth capacitance becomes small, where the capacitance change amount of the fourth capacitance is denoted as Δcz1. Acceleration in the Z direction can be acquired based on Δcz1.
In an embodiment, the number of the fourth fixed electrodes 154 may be two, and the fourth fixed electrodes are respectively located between the first fixed electrode 151 and the third fixed electrode 153, and between the third fixed electrode 153 and the second fixed electrode 152. Thus, two Δcz1 can be obtained, and the acceleration in the Z direction can be obtained based on the average value of the two Δcz1, so that the accuracy of the detection result can be improved.
In an embodiment, in each of the hollow areas 143, a fifth fixed electrode 155 is further disposed on the substrate 110, and the sidewall 6 of the hollow area 143 and the fifth fixed electrode 155 form a fifth capacitor. When the first region 121 moves upward, the distance between the fifth fixed electrode 155 and the sidewall 6 of the hollowed-out region 143 becomes larger, so that the capacitance value of the fifth capacitor becomes smaller, where the capacitance variation of the fifth capacitor is denoted as Δcy2. When the acceleration in the Y direction is detected, the variation amplitude of the deltaCY 1 and the variation amplitude of the deltaCY 2 are opposite in the same direction, and the acceleration in the Y direction is obtained based on the difference value of the deltaCY 1 and the deltaCY 2, so that the accuracy and the reliability of a detection result can be improved.
The hollowed-out area 143 may be disposed at a middle position of the first area 121 along the X direction and near the first spring beam 123 at the same time, so that when acceleration exists in the X direction and the Y direction at the same time, an influence of torsion of the first area 121 on a detection result of the acceleration in the Y direction can be significantly reduced.
In another embodiment, instead of providing a hollowed-out area on the first area 121, a hollowed-out area may be provided on the second area 122, where the hollowed-out area may form a capacitor with a fixed electrode on the substrate 110 for detecting acceleration in the Y direction.
In one embodiment, a sixth fixed electrode 156 is further disposed on the substrate 110, and a sixth capacitance is formed between the sixth fixed electrode 156 and the second region 122. The sixth capacitance is also used to detect acceleration in the Z direction. When the first region 121 rotates in the positive Z direction, the second region 122 rotates in the negative Z direction, and the distance between the second region 122 and the sixth fixed electrode 156 becomes smaller, so that the capacitance value of the sixth capacitance becomes larger, where the capacitance change amount of the sixth capacitance is denoted as Δcz2. When the acceleration in the Z direction is detected, the change amplitude of the delta CZ1 and the change amplitude of the delta CZ2 are opposite in the same direction, differential output is formed, the acceleration in the Z direction is obtained based on the difference value of the delta CZ1 and the delta CZ2, and the accuracy and the reliability of a detection result can be improved. Further, the number of the sixth fixed electrodes 156 may be the same as the number of the fourth fixed electrodes 154, and the arrangement positions of the sixth fixed electrodes 156 on the second area 122 may correspond to the arrangement positions of the fourth fixed electrodes 154 on the first area 121, which is not described herein.
Further, when the acceleration in the X direction is acquired based on the difference between Δcx1 and Δcx2, the acceleration existing in the Z direction does not affect the detection result in the X direction. Since the difference between Δcx1 and Δcx2 can cancel the influence of the acceleration in the Z direction. Similarly, the acceleration in the Y direction does not affect the detection result in the X direction.
Similarly, the acceleration in the Z direction is obtained based on the difference between Δcz1 and Δcz2, so that the accelerations existing in the X and Y directions do not affect the detection result in the Z direction, avoiding cross coupling.
In an embodiment, movable electrodes may be simultaneously disposed on the first region 121 and the second region 122 to enable detection of acceleration in the X direction. For example, the first movable electrode 141 and the second movable electrode 142 are provided in the first region 121, and the third movable electrode 144 and the fourth movable electrode 145 are provided in the second region 122. The third movable electrode 144 and the fourth movable electrode 145 are similar in structure to the first movable electrode 141 and the second movable electrode 142, respectively. Correspondingly, a seventh fixed electrode 157 and an eighth fixed electrode 158 are also provided on the substrate 110. The third movable electrode 144 and the seventh fixed electrode 157 may constitute a capacitance, the capacitance change amount of which may be denoted as Δcx1, and the fourth movable electrode 145 and the eighth fixed electrode 158 may constitute a capacitance, the capacitance change amount of which may be denoted as Δcx2. The third movable electrode 144 and the fourth movable electrode 145 may be provided by increasing the number of Δcx1 and Δcx2, and the accuracy of the detection result may be improved by acquiring the acceleration in the X direction based on the difference between the average value of the plurality of Δcx1 and the average value of the plurality of Δcx2.
Specifically, the distance between the comb teeth 7 of the seventh fixed electrode 157 and the comb teeth 8 of the third movable electrode 144 or the side wall 8 '(the side wall 8' can be regarded as a part of the third movable electrode 144) in the second region 122 is changed, thereby generating Δcx1. Further, the distance between the comb teeth 9 of the eighth fixed electrode 158 and the comb teeth 10 of the fourth movable electrode 145 or the side wall 10 '(the side wall 10' can be regarded as a part of the fourth movable electrode 145) in the second region 122 is changed, thereby generating Δcx2.
In an embodiment, on the basis that the first area 121 is provided with the hollowed-out area 143, the second area 122 may be further provided with the hollowed-out area 146. The hollowed-out region 146 is similar in structure to the hollowed-out region 143. Correspondingly, in the hollowed-out area 146, a ninth fixed electrode 159 and a tenth fixed electrode 160 are further disposed on the substrate 110.
Specifically, the sidewall 11 of the hollow area 146 and the ninth fixed electrode 159 can form a capacitor, the capacitance variation of the capacitor can be denoted as Δcy1, and the sidewall 12 of the hollow area 146 and the tenth fixed electrode 160 can form a capacitor, and the capacitance variation of the capacitor can be denoted as Δcy2.
The arrangement of the hollowed-out area 146, the ninth fixed electrode 159 and the tenth fixed electrode 160 can increase the number of Δcy1 and Δcy2, and the accuracy of the detection result can be improved by acquiring the acceleration in the Y direction based on the difference between the average value of the plurality of Δcy1 and the average value of the plurality of Δcy2. In addition, since the detection electrodes in the Y direction are disposed vertically and horizontally, the influence of the torsion in the X direction on the detection result in the Y direction can be canceled by the detection electrodes on the left and right sides (left: third and ninth fixed electrodes 153 and 159; right: fifth and tenth fixed electrodes 155 and 160), and the influence of the torsion in the Z direction on the detection result in the Y direction can be canceled by the detection electrodes on the upper and lower portions (upper: third and fifth fixed electrodes 153 and 155; lower: ninth and tenth fixed electrodes 159).
According to an embodiment of the present application, the substrate 110 is provided with first and second fixed electrodes 151 and 152 for detecting acceleration in the X direction, third and fifth fixed electrodes 153 and 155 for detecting acceleration in the Y direction, and fourth and sixth fixed electrodes 154 and 156 for detecting acceleration in the Z direction, wherein the first, third and fourth fixed electrodes 151, 153 and 154 are connected to leads located at one side of the substrate 110, respectively, and the second, fifth and sixth fixed electrodes 152, 155 and 156 are connected to leads located at the other side of the substrate 110, respectively.
Specifically, referring to fig. 1 and 2, the first fixed electrode 151 may be fixed on the substrate 110 through two connection points X1a and X1b, and the second fixed electrode 152 may be fixed on the substrate 110 through two connection points X2a and X2 b. The third fixed electrode 153 may be fixed to the substrate 110 through a connection point Y1a, and the fifth fixed electrode 155 may be fixed to the substrate 110 through a connection point Y2 a. Here, the connection points X1a, X1b, X2a, X2b, Y1a, and Y2a may not only function to support the fixed electrode, but also serve to achieve electrical connection between the fixed electrode and the corresponding lead. For example, the first fixed electrode 151 may be electrically connected to an X1 lead through a connection point X1b, and the X1 lead may be led out to one end of the substrate 110 for electrically connecting with other components or devices, such as components or devices for detecting a capacitance value, and the like. Similarly, the second fixed electrode 152 may be electrically connected to an X2 lead through a connection point X2b, and the X2 lead may be led out to the other end of the substrate 110. The third fixed electrode 153 may be electrically connected to a Y1 lead through a connection point Y1a, and the Y1 lead may be drawn out to one end of the substrate 110. The fifth fixed electrode 155 may be electrically connected to a Y2 lead through a connection point Y2a, and the Y2 lead may be drawn to the other end of the substrate 110.
Further, the fourth and sixth fixed electrodes 154 and 156 may be disposed directly on the substrate 110. The fourth fixed electrode 154 may be drawn out to one end of the substrate 110 through a lead Z1, and the sixth fixed electrode 156 may be drawn out to the other end of the substrate 110 through a lead Z2.
In this embodiment, the X1, Y1 and Z1 leads are all distributed at one end of the substrate 110, and the X2, Y2 and Z2 leads are all distributed at the other end of the substrate 110, so that effective layout and management of the leads can be achieved, and the situation that the detection result is wrong due to mixing of electrodes connected with the leads is avoided.
For example, if the X1 and X2 leads are disposed at one end of the substrate 110 and the Y1 and Y2 leads are disposed at the other end of the substrate 110, when the external interfaces of the other components or devices and the leads are connected to detect the corresponding capacitance values, the external interfaces of the X1 and X2 leads are easily mistaken for the external interfaces of the Y1 and Y2 leads, and the external interfaces of the Y1 and Y2 leads are mistaken for the external interfaces of the X1 and X2 leads, that is, the detection results in the X and Y directions are easily inverted. In particular, when the chip (or the acceleration sensor) is put on the back, the case where the detection results in the X and Y directions are reversed is more likely to occur.
Further, the arrangement order of the external interfaces of the X1, Y1 and Z1 leads at one end of the substrate 110 corresponds to the arrangement order of the external interfaces of the X2, Y2 and Z2 leads at the other end of the substrate 110. Here, one end and the other end may be both ends located on the same side of the substrate 110. For example, as shown in fig. 2, the external interfaces of the X1, Z1 and Y1 leads are sequentially arranged at one end of the substrate 110 from left to right, and the external interfaces of the X2, Z2 and Y2 leads are sequentially arranged at the other end of the substrate 110 from right to left. Thus, when the chip is inverted, at most, X1 and X2 are inverted, Y1 and Y2 are inverted, and Z1 and Z2 are inverted, and the detection result is not affected.
When the number of the third fixed electrode 153 and the fifth fixed electrode 155 is plural, the number of the corresponding connection points Y1a and Y2a is plural. The plurality of connection points Y1a are electrically connected to the lead Y1, and the plurality of connection points Y2a are electrically connected to the lead Y2.
In an embodiment, a seventh fixed electrode 157 and an eighth fixed electrode 158 for detecting acceleration in the X direction, and a ninth fixed electrode 159 and a tenth fixed electrode 160 for detecting acceleration in the Y direction are further provided on the substrate 110. The seventh fixed electrode 157 may be fixed on the substrate 110 through two connection points X1c and X1d, and the eighth fixed electrode 158 may be fixed on the substrate 110 through two connection points X2c and X2 d. The ninth fixed electrode 159 may be fixed to the substrate 110 through a connection point Y1b, and the tenth fixed electrode 160 may be fixed to the substrate 110 through a connection point Y2 b. Here, the connection points X1c, X1d, X2c, X2d, Y1b, and Y2b may not only function to support the fixed electrode, but also serve to achieve electrical connection between the fixed electrode and the corresponding lead. In this embodiment, the connection point X1b may be electrically connected to the connection point X1c through one segment of the X1 wire, the connection point X1c may be electrically connected to the connection point X1d through the seventh fixed electrode 157 itself, the connection point X1d may be electrically connected to another segment of the X1 wire, and the other segment of the X1 wire may be led out to one end of the substrate 110. The connection point X2b may be electrically connected to the connection point X2c through one segment of the X2 lead, the connection point X2c may be electrically connected to the connection point X2d through the eighth fixed electrode 158 itself, the connection point X2d may be electrically connected to another segment of the X2 lead, and the other segment of the X2 lead may be led out to the other end of the substrate 110. The ninth fixed electrode 159 may be electrically connected to a Y1 lead through a connection point Y1b, and the Y1 lead may be drawn out to one end of the substrate 110. The tenth fixed electrode 160 may be electrically connected to a Y2 lead through a connection point Y2b, and the Y2 lead may be drawn to the other end of the substrate 110.
In an embodiment, the number of the sixth fixed electrodes 156 may be the same as the number of the fourth fixed electrodes 154, and two. One fourth fixed electrode 154 is located between the first fixed electrode 151 and the third fixed electrode 153, and the other fourth fixed electrode 154 is located between the second fixed electrode 152 and the fifth fixed electrode 155. One sixth fixed electrode 156 is located between the seventh fixed electrode 157 and the ninth fixed electrode 159, and the other sixth fixed electrode 156 is located between the eighth fixed electrode 158 and the tenth fixed electrode 160. Referring to fig. 1 and 2, two fourth fixed electrodes 154 may be respectively provided with a connection point Z1a, and the two connection points Z1a may be connected by a wire 171, thereby achieving electrical connection between the two fourth fixed electrodes 154; the two sixth fixed electrodes 156 may be respectively provided with a connection point Z2a, and the two connection points Z2a may be connected by a wire 172, so as to implement electrical connection between the two sixth fixed electrodes 156. The wires 171 and 172 are not directly disposed on the substrate 110, but are vacated by connection points Z1a and Z2a, respectively, to be disposed on the substrate 110. The wire 171 and the wire 172 correspond to bridges for connecting the respective fixed electrodes. As shown in fig. 1, a hollowed-out area may be disposed on the first area 121, such that the conductive wire 171 is located in the hollowed-out area. Similarly, a hollowed-out area may be disposed on the second area 122, such that the conductive wire 172 is located in the hollowed-out area.
In an embodiment, as shown in fig. 2, the first fixing point 131 and the second fixing point 132 may not only function to support the mass 120, but also serve to achieve an electrical connection between the mass 120 and the corresponding lead. For example, the first fixation point 131 may be electrically connected to the second fixation point 132 through the mass 120 itself, and the second fixation point 132 may be electrically connected to the lead 173. Leads 173 may lead out to one end of substrate 110 for electrical connection with other components or devices.
The acceleration sensor 100 according to an embodiment of the present application is generally described below with reference to fig. 1 and 2, and specific details thereof are not described herein.
As shown in fig. 1 and 2, the acceleration sensor 100 includes a substrate 110 and a mass 120. The mass 120 includes a first region 121, a second region 122, a first spring beam 123, a second spring beam 124, a third spring beam 125, and a frame 126. The first spring beam 123, the second spring beam 124, and the third spring beam 125 each extend in the X direction. The first region 121 and the second region 122 are connected to the frame 126 by a first spring beam 123 therebetween. The second spring beam 124 is located between the first region 121 and the frame 126, and both ends of the second spring beam 124 are connected with the frame 126; the third spring beam 125 is located between the second region 122 and the frame 126, and both ends of the third spring beam 125 are connected to the frame 126. The second and third spring beams 124 and 125 are connected to first and second fixed points 131 and 132, respectively, provided on the substrate 110 to achieve a movable connection between the mass 120 and the substrate 110.
The first region 121 is provided with a first movable electrode 141 and a second movable electrode 142, and the second region 122 is provided with a third movable electrode 144 and a fourth movable electrode 145. The first movable electrode 141 and the first fixed electrode 151 on the substrate 110, the second movable electrode 142 and the second fixed electrode 152 on the substrate 110, the third movable electrode 144 and the seventh fixed electrode 157 on the substrate 110, and the fourth movable electrode 145 and the eighth fixed electrode 158 on the substrate 110 can be used together to detect acceleration in the X direction.
The first area 121 is further provided with a plurality of hollow areas 143, and the plurality of hollow areas 143 are located between the first movable electrode 141 and the second movable electrode 142. The second region 122 is further provided with a plurality of hollow regions 146, and the plurality of hollow regions 146 are located between the third movable electrode 144 and the fourth movable electrode 145. The hollowed-out area 143, the third fixed electrode 153 and the fifth fixed electrode 155 on the substrate 110, and the hollowed-out area 146, the ninth fixed electrode 159 and the tenth fixed electrode 160 on the substrate 110 can be used together to detect the acceleration in the Y direction.
Two fourth fixed electrodes 154 are provided on the substrate 110 at portions corresponding to the first regions 121, and two sixth fixed electrodes 156 are provided on the substrate 110 at portions corresponding to the second regions 122. One fourth fixed electrode 154 is located between the first fixed electrode 151 and the third fixed electrode 153, and the other fourth fixed electrode 154 is located between the second fixed electrode 152 and the fifth fixed electrode 155. One sixth fixed electrode 156 is located between the seventh fixed electrode 157 and the ninth fixed electrode 159, and the other sixth fixed electrode 156 is located between the eighth fixed electrode 158 and the tenth fixed electrode 160. The first region 121 and the fourth fixed electrode 154, and the second region 122 and the sixth fixed electrode 156 may be used together to detect acceleration in the Z direction.
The acceleration sensor provided by the embodiment of the application can be regarded as a single mass block three-beam acceleration sensor, and the acceleration sensor with the structure can avoid the mutual influence of detection results in three directions and cross coupling through the symmetrical arrangement and differential output of the detection electrodes.
The embodiment of the application also provides an electronic device, which comprises the acceleration sensor 100 according to any one of the above embodiments. The electronic device may be used to detect acceleration in the X-direction.
The embodiment of the application provides electronic equipment, which can remarkably reduce the size of a mass block and the area of a chip by arranging the mass block into a first area and a second area which can mutually twist around a Z axis perpendicular to the plane of the mass block and detecting the acceleration in the X direction based on the mutual twisting of the first area and the second area, thereby realizing the miniaturization of an acceleration sensor.
Further, the electronic device may be configured to detect X, Y and acceleration in the Z direction.
Any combination of the above optional solutions may be adopted to form an optional embodiment of the present application, which is not described herein.
In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "examples," and the like, means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, whereby features defining "first," "second," or the like, may explicitly or implicitly include at least one such feature.
The foregoing description of the preferred embodiments of the application is not intended to be limiting, but rather is to be construed as including any modifications, equivalents, and alternatives falling within the spirit and principles of the application.