Micromechanical sensor
By employing a stacked arrangement and direct conductive connection between micromechanical chips and analysis processing chips in micromechanical sensors, the problem of increased housing size is solved, achieving efficient space utilization and low-cost manufacturing, while improving signal-to-noise ratio and current consumption efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2021-09-17
- Publication Date
- 2026-06-02
Smart Images
Figure CN114249291B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a micromechanical sensor. Background Technology
[0002] Micromechanical sensors used to measure physical parameters such as acceleration, rotational speed, pressure, and others are mass-produced for a variety of applications in fields such as automotive and consumer electronics. Combined speed and acceleration sensors mounted in a common housing play an increasingly important role. The combination of a triaxial speed sensor and a triaxial acceleration sensor is also known as an IMU (Inertial Measurement Unit).
[0003] Micromechanical chips, also known as MEMS chips, can be used in the sensor. Here, the micromechanical chip can include a microelectromechanical system (MEMS). The sensor may also include one or more analysis processing chips, which may be configured, for example, as an ASIC (Application-Specific Integrated Circuit).
[0004] However, the multiple analysis and processing chips result in an increased housing size and consequently, a larger sensor size, which is undesirable. For many applications, increased housing size is intolerable. Especially in wearable devices (such as smartwatches) and audio devices (such as Bluetooth in-ear headphones), structural size is a decisive criterion for the market success of sensors. Summary of the Invention
[0005] The objective of this invention is to describe a micromechanical sensor with high space utilization, in which the housing size can be kept as small as possible.
[0006] This task is solved using a micromechanical sensor according to the invention. Advantageous configurations are described below.
[0007] This invention relates to a micromechanical sensor having a micromechanical chip, a first analytical processing chip, and a second analytical processing chip. The micromechanical chip has a first micromechanical structure, the first analytical processing chip has a first application-specific integrated circuit (ASIC), and the second analytical processing chip has a second ASIC. Here, the micromechanical structure may include a microelectromechanical system (MEMS). The first analytical processing chip and the micromechanical chip are arranged in a stacked manner. This means that the first analytical processing chip and the micromechanical chip are arranged at least substantially vertically above each other. In particular, the first analytical processing chip and the micromechanical chip can be arranged directly adjacent to each other, wherein, for example, the first analytical processing chip may at least partially protrude beyond the micromechanical chip, or the micromechanical chip may at least partially protrude beyond the first analytical processing chip. The micromechanical chip and the first analytical processing chip are electrically directly connected. Therefore, the conductive connection between the micromechanical chip and the first analytical processing chip is directly guided, and thus the conductive connection is not guided through a possible substrate. The first analytical processing chip and the second analytical processing chip are electrically directly connected. Therefore, the conductive connection between the first analytical processing chip and the second analytical processing chip is also directly guided (i.e., not through a possible substrate). The first application-specific integrated circuit (ASIC) mainly includes analog circuit elements. The second application-specific integrated circuit mainly includes digital circuit elements.
[0008] This arrangement enables the creation of micromechanical sensors with high space utilization.
[0009] In one embodiment of this sensor, the first technology node of the first analysis processing chip is larger than the second technology node of the second analysis processing chip. This further improves space utilization. In particular, compared to digital circuit elements, analog circuit elements require larger technology nodes to achieve particularly good signal-to-noise ratios and / or particularly low current consumption while maintaining relatively low manufacturing costs. As is common in semiconductor technology, the term "technology node" here refers to a milestone defining a generation of manufacturing processes and essentially relates to the smallest lithographically achievable structural size.
[0010] In one embodiment of this sensor, the first technology node is in the range of 80 to 180 nanometers, and / or the second technology node is less than 70 nanometers. This enables further improvements in space utilization.
[0011] In one embodiment of the sensor, it further includes another micromechanical chip having a second micromechanical structure. The second analysis processing chip and the other micromechanical chip are stacked, wherein the other micromechanical chip is electrically and directly connected to the first analysis processing chip. Therefore, the conductive connection between the other micromechanical chip and the first analysis processing chip is directly guided, and thus the conductive connection is not guided through a possible substrate.
[0012] In one embodiment of this sensor, a first bonding pad assembly of a micromechanical chip is connected to a first analysis and processing chip via bonding wires. A second bonding pad assembly of another micromechanical chip is connected to the first analysis and processing chip via bonding wires. The first and second bonding pad assemblies are arranged perpendicular to each other. This allows for further improvement in space utilization.
[0013] In one embodiment of the sensor, the micromechanical chip has a second micromechanical structure. The second analysis processing chip and the micromechanical chip are stacked. Either both the first and second analysis processing chips are positioned above the micromechanical chip, or both are positioned below it. This allows for further improvement in space utilization.
[0014] In one embodiment of the sensor, a first micromechanical structure is configured to measure three-dimensional rotational speed, and a second micromechanical structure is configured to measure three-dimensional acceleration.
[0015] In one embodiment of the sensor, it also includes a substrate. A communication disk is arranged on the substrate, wherein a first analysis processing chip and / or a second analysis processing chip are electrically connected to the communication disk. Specifically, the first analysis processing chip can be electrically connected to the communication disk, and the second analysis processing chip can be connected only to the first analysis processing chip. In this case, the second analysis processing chip can be turned off, for example, when it is not needed. This can be done by logic devices present on the first analysis processing chip, thereby saving energy during the operation of the micromechanical sensor. Alternatively, the second analysis processing chip can also be electrically connected to the communication disk, and the first analysis processing chip can be connected only to the second analysis processing chip. This enables simpler communication and savings in electrical connections.
[0016] In one embodiment of this sensor, it has a housing. The housing is a mold housing. The substrate is an integrated circuit board substrate. This enables cost-effective manufacturing of the sensor.
[0017] In one embodiment of this sensor, the first analysis processing chip and the second analysis processing chip are connected to each other via bonding wires. This enables a highly efficient electrical connection between the first and second analysis processing chips. Attached Figure Description
[0018] Embodiments of the present invention are illustrated with reference to the following accompanying drawings. The schematic drawings show:
[0019] Figure 1 This shows a micromechanical sensor;
[0020] Figure 2 Show Figure 1 A cross-sectional view of a micromechanical sensor;
[0021] Figure 3 Another micromechanical sensor is shown;
[0022] Figure 4 Show Figure 3 A cross-sectional view of another micromechanical sensor;
[0023] Figure 5 Show Figure 3 Another cross-sectional view of another micromechanical sensor;
[0024] Figure 6 Another micromechanical sensor is shown;
[0025] Figure 7 Show Figure 6 A cross-sectional view of another micromechanical sensor; and
[0026] Figure 8 Another micromechanical sensor is shown. Detailed Implementation
[0027] Figure 1 A micromechanical sensor 1 is shown, comprising a micromechanical chip 2 having a first micromechanical structure, a first analysis processing chip 3, and a second analysis processing chip 4. The first analysis processing chip has a first application-specific integrated circuit (ASIC) 31, and the second analysis processing chip has a second ASIC 41. The micromechanical chip 2 is disposed on an optional substrate 13. The first analysis processing chip 3 and the micromechanical chip 2 are arranged vertically, i.e., stacked, on top of each other. The micromechanical chip 2 and the first analysis processing chip 3 are electrically connected. This connection is... Figure 1 This is implemented using bonding wires 11 that guide from the chip pad 22 of the micromachined chip 2 to the chip connection pad 32 of the first analysis and processing chip 3. Other conductive connections can also be provided (e.g., via vias or direct bonding pad connections), however, not in... Figure 1As shown in the diagram, the first analysis processing chip 3 and the second analysis processing chip 4 are electrically connected. This connection is achieved via bonding wires 11 that run from the first data exchange disk 33 of the first analysis processing chip 3 to the second data exchange disk 42 of the second analysis processing chip 4; however, it can also be different from the connection shown in the diagram. Figure 1 It is implemented as shown. The first application-specific integrated circuit 31 mainly includes analog circuit elements, and the second application-specific circuit 41 mainly includes digital circuit elements.
[0028] A communication disk 12 is arranged on the substrate 13, and the communication disk is connected to the analysis and processing communication disk 34 of the first analysis and processing chip 3 via bonding wires 11. Data from the first analysis and processing chip 3 outside the micromechanical sensor 1 can be provided via the communication disk 13. A chip disk 22 is arranged in the first bonding disk group 23. The number of connections implemented via bonding wires 11 may differ from the number of connections on the substrate 13. Figure 1 The quantities shown are selected by those skilled in the art based on the prerequisites necessary for chips 2, 3, and 4.
[0029] Figure 2 Show Figure 1 The image shows a cross-sectional view of the micromechanical sensor 1 in a region of the bonding wire 11 that leads from the first data exchange disk 33 to the second data exchange disk 42. The micromechanical chip 2 includes a first micromechanical structure 21, which may be configured, for example, as a pressure sensor, an acceleration sensor, or a rotational speed sensor.
[0030] In one embodiment, the first technology node of the first analysis processing chip 3 is greater than the second technology node of the second analysis processing chip 4. In one embodiment, the first technology node is in the range of 80 to 180 nanometers. In one embodiment, the second technology node is less than 70 nanometers.
[0031] Figure 3 The micromechanical sensor 1 is shown, which corresponds to Figure 1 and 2 The micromechanical sensor 1, unless otherwise described below, has the following characteristics. The micromechanical sensor 1 also includes another micromechanical chip 5, which has a second micromechanical structure. This other micromechanical chip 5 is disposed on an optional substrate 13. The second analysis processing chip 4 and the other micromechanical chip 5 are disposed vertically, i.e., stacked. The other micromechanical chip 5 is electrically connected to the first analysis processing chip 3. This connection is... Figure 3 The connection is implemented using bonding wires 11 that are guided from other chip pads 52 of another micromachined chip 5 to other chip connection pads 35 of the first analysis and processing chip 3. Other conductive connections can also be provided (e.g., via vias or direct bonding pad connections), however, not in... Figure 3 As shown in the diagram. Other chip disks 52 are arranged in the second bonding disk group 53.
[0032] The first analytical processing chip 3 is arranged above the micromechanical chip 2. The second analytical processing chip 4 is arranged above another micromechanical chip 5. In an alternative configuration, the first analytical processing chip 3 may be arranged below the micromechanical chip 2 and / or the second analytical processing chip 4 may be arranged below another micromechanical chip 5. Which arrangement is most advantageous depends particularly on the chip area required for the two micromechanical chips 2, 5 and the two analytical processing chips 3, 4, wherein, typically, but not necessarily, the larger chips are arranged below the smaller chips.
[0033] Figure 4 Show Figure 3 The image shows a cross-sectional view of the micromechanical sensor 1 in a region of the bonding line 11 that leads from another chip connection pad 35 to another chip pad 52. The other micromechanical chip 5 includes a second micromechanical structure 51, which may be configured as, for example, a pressure sensor, an acceleration sensor, or a rotational speed sensor.
[0034] Figure 5 Show Figure 3 A cross-sectional view of the micromechanical sensor 1 in a region of the bonding wire 11 that leads from the first data exchange disk 33 to the second data exchange disk 42.
[0035] In one embodiment, the first bonding pad group 23 of the micromechanical chip 2 is connected to the first analysis and processing chip 3 via bonding wires 11. Furthermore, the second bonding pad group 53 of another micromechanical chip 5 is connected to the first analysis and processing chip 3 via bonding wires 11. The first bonding pad group 23 and the second bonding pad group 53—as in… Figure 3 As shown in the diagram—arranged perpendicular to each other.
[0036] Figure 6 The micromechanical sensor 1 is shown, which corresponds to Figure 1 and 2 The micromechanical sensor 1 is described below unless otherwise specified. The micromechanical chip 2 has a second micromechanical structure in which the second analysis processing chip 4 and the micromechanical chip 2 are stacked. Both the first analysis processing chip 3 and the second analysis processing chip 4 are disposed on top of the micromechanical chip 2.
[0037] In addition Figure 6 As shown, the communication disk 12 of the substrate 13 is connected to the other analysis processing communication disks 43 of the second analysis processing chip 4. Therefore, the analysis processing communication disk 34 of the first analysis processing chip 3 is not present. Figure 6 This configuration can also be set in Figures 1 to 5 In the embodiments. Alternatively, Figure 6The embodiment can also replace other analysis processing communication disks 43 in the second analysis processing chip 4, as in Figure 1 The analysis and processing communication disk 34 has a first analysis and processing chip 3 as shown.
[0038] If the first analysis and processing chip 3 and the communication disk 12 can be electrically connected and the second analysis and processing chip 4 is only connected to the first analysis and processing chip 3, such as in Figure 1 and 3 As shown, the second analysis processing chip 4 can be turned off, for example, when it is not needed. This can be done by logic devices present on the first analysis processing chip 3, thereby saving energy during the operation of the micromechanical sensor 1. If the second analysis processing chip 4 can be electrically connected to the communication disk 12 and the first analysis processing chip 3 is only connected to the second analysis processing chip 4, as shown in Figure 6 As shown in the diagram, this enables simpler communication and savings in electrical connections.
[0039] Figure 7 Show Figure 6 The image shows a cross-sectional view of the micromechanical sensor 1 in a region of the bonding wire 11 that leads from the first data exchange disk 33 to the second data exchange disk 42. The micromechanical chip 2 includes not only the first micromechanical structure 21 but also the second micromechanical structure 51.
[0040] Also in Figure 7 The cross-sectional view shows housing 6, which is a mold housing. In this case, substrate 13 can be an integrated circuit board substrate. Mold material 61 can be arranged inside housing 6, wherein, in particular, micromechanical chip 2, analysis and processing chips 3 and 4, and bonding wires are embedded in mold material 61, thus providing mechanical protection for the components. Figure 7 The housing can also be set in Figures 1 to 5 In the embodiments described above.
[0041] exist Figure 3 and 4 In the embodiments, but also in Figure 5 and 6 In one embodiment, the first micromechanical structure 21 may be configured to measure three-dimensional rotational speed, and the second micromechanical structure 51 may be configured to measure three-dimensional acceleration.
[0042] In all embodiments, the first analysis processing chip 3 may particularly include analog front-end circuitry for manipulating and analyzing signals from the micromechanical chip 2 or micromechanical chips 2, 5, while the second analysis processing chip 4 particularly includes a microprocessor and / or a digital signal processor and / or a storage unit. More complex calculations and larger data volumes can be performed on the microprocessor and / or digital signal processor to enable additional functions such as data fusion, self-calibration, and special filtering.
[0043] Figure 8 The micromechanical sensor 1 is shown, which corresponds to Figures 3 to 5 The micromechanical sensor 1 is described below without any differences. The micromechanical sensor 1 also has a micromechanical chip 7 with a third micromechanical structure, which can be constructed similarly to the first micromechanical structure 21 or the second micromechanical structure 51. Here, the other micromechanical chip 7 is disposed on an optional substrate 13. A third analysis processing chip 8 with a third dedicated circuit 81 is disposed above the other micromechanical chip 7. The third analysis processing chip 8 and the other micromechanical chip 7 are disposed vertically, i.e., stacked. The other micromechanical chip 7 is electrically connected to the first analysis processing chip 3. This connection is... Figure 3 The connection is implemented using bonding wires 11 that are guided from other chip pads 72 of another micromachined chip 7 to other chip connection pads 37 of the first analysis and processing chip 3. Other conductive connections (e.g., via vias or direct bonding pad connections) can also be provided, however, not in... Figure 3 As shown in the diagram. Other chip disks 72 are arranged in the third bonding disk group 73. The first analysis processing chip 3 and the third analysis processing chip 8 are electrically connected. This connection is achieved by bonding lines 11 leading from the other first data exchange disks 36 of the first analysis processing chip 3 to the third data exchange disk 82 of the third analysis processing chip 8; however, it can also be different from the bonding lines 11 shown in the diagram. Figure 8 It is implemented as shown. The third dedicated circuit 81, similar to the second dedicated circuit 41, mainly comprises digital circuit elements. The third bonding disk group 73 is here perpendicular to the first bonding disk group 23 and parallel to the second bonding disk group 53.
[0044] Unlike Figure 8 The illustration shows that the micromechanical sensor 1 can also be implemented without another micromechanical chip 7 or without a third analysis and processing chip 8.
[0045] Although the invention has been described in detail with reference to preferred embodiments, the invention is not limited to the disclosed examples, and other variations can be derived by those skilled in the art without departing from the scope of protection of the invention.
Claims
1. A micromechanical sensor (1), the micromechanical sensor having a micromechanical chip (2), the micromechanical chip having a first micromechanical structure (21), the micromechanical sensor further having a first analysis and processing chip (3), the first analysis and processing chip having a first application-specific integrated circuit (31), and the micromechanical sensor having a second analysis and processing chip (4), the second analysis and processing chip having a second application-specific integrated circuit (41), wherein, The first analysis processing chip (3) and the micromechanical chip (2) are stacked, wherein the micromechanical chip (2) and the first analysis processing chip (3) are electrically and directly connected, wherein the first analysis processing chip (3) and the second analysis processing chip (4) are electrically and directly connected, wherein the first application-specific integrated circuit (31) includes analog circuit elements, and wherein the second application-specific integrated circuit (41) includes digital circuit elements. The micromechanical sensor also has another micromechanical chip (5), which has a second micromechanical structure (51). The second analysis processing chip (4) and the other micromechanical chip (5) are stacked. The other micromechanical chip (5) is electrically and directly connected to the first analysis processing chip (3). The first bonding pad group (23) of the micromechanical chip (2) is connected to the first analysis processing chip (3) via bonding wires (11). The second bonding pad group (53) of the other micromechanical chip (5) is connected to the first analysis processing chip (3) via bonding wires (11). The first bonding pad group (23) and the second bonding pad group (53) are arranged perpendicularly to each other. The micromechanical chip (2) has a second micromechanical structure (51), wherein the second analysis processing chip (4) and the second micromechanical structure (51) of the micromechanical chip (2) are stacked, wherein the first analysis processing chip (3) and the second analysis processing chip (4) are both arranged above the micromechanical chip (2), or both are arranged below the micromechanical chip (2), wherein the second analysis processing chip (4) and the first analysis processing chip (3) are electrically connected directly, wherein the first bonding disk group (23) of the micromechanical chip (2) is connected to the first analysis processing chip (3) by means of bonding wire (11), wherein the second data exchange disk group of the second analysis processing chip (4) is connected to the first analysis processing chip (3) by means of bonding wire (11), the second data exchange disk (42) of the second analysis processing chip (4) is arranged in the second data exchange disk group, wherein the first bonding disk group (23) and the second data exchange disk group are arranged perpendicular to each other.
2. The micromechanical sensor (1) according to claim 1, wherein, The first technology node of the first analysis and processing chip (3) is greater than the second technology node of the second analysis and processing chip (4).
3. The micromechanical sensor (1) according to claim 2, wherein, The first technology node is in the range of 80 to 180 nanometers, and / or the second technology node is less than 70 nanometers.
4. The micromechanical sensor (1) according to any one of claims 1 to 3, wherein, The first micromechanical structure (21) is configured to measure three-dimensional rotational speed, wherein the second micromechanical structure (51) is configured to measure three-dimensional acceleration.
5. The micromechanical sensor (1) according to any one of claims 1 to 3, wherein the micromechanical sensor further comprises a substrate (13), wherein, A communication disk (12) is arranged on the substrate (13), wherein the first analysis processing chip (3) and / or the second analysis processing chip (4) are electrically connected to the communication disk (12).
6. The micromechanical sensor (1) according to claim 5, wherein the micromechanical sensor further comprises a housing (6), wherein, The housing (6) is a mold housing, wherein the substrate (13) is an integrated circuit board substrate.
7. The micromechanical sensor (1) according to any one of claims 1 to 3, wherein, The first analysis processing chip (3) and the second analysis processing chip (4) are connected to each other by means of bonding wire (11).