Sensor having package with sensor die
Patent Information
- Application Number
- JP2024146157
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-09-01
- Filing Date
- 2024-08-28
- Publication Date
- 2025-03-14
Smart Images
Figure 2025036279000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to sensors, and more particularly to sensors having a package that includes a substrate and a sensor die attached to the substrate. [Background technology]
[0002] A sensor, such as a pressure sensor, typically includes a housing and a diaphragm attached to the housing. Oil is disposed within a passageway in the housing, and a sensor die is disposed within the oil on the housing. When an external pressure is applied to the diaphragm, the diaphragm deflects, transmitting the external pressure to the oil surrounding the die, which applies the same external pressure to the die. The die deflects in response to the external pressure and generates an electrical signal representative of the external pressure.
[0003] This type of pressure sensor generally has two diaphragms to transmit two external pressures to the die, allowing the die to measure the differential pressure between the two external pressures. However, the two diaphragms are often axially opposite each other, which requires a wide passage in the housing to transmit the appropriate pressure to the die. Positioning the diaphragms in an axially opposite arrangement and positioning the die within the housing complicates the manufacture of the sensor. Summary of the Invention [Means for solving the problem]
[0004] The sensor includes a housing having a body and a plurality of ports, a plurality of diaphragms each disposed in one of the ports, and a package having a substrate and a sensor die attached to the substrate. The body has a first side and an opposing second side. The ports extend from the first side of the body. The substrate is attached to the second side of the body, and the sensor die is disposed in an enclosed containment space partially defined by the substrate.
[0005] The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]
[0006] [Figure 1] FIG. 1 is a perspective view of a sensor according to one embodiment. [Diagram 2] FIG. 2 is a partially exploded perspective view of the sensor of FIG. 1. [Diagram 3] FIG. 2 is a cross-sectional side view of the sensor of FIG. 1. [Figure 4] FIG. 13 is a perspective view of a sensor according to another embodiment. [Diagram 5] FIG. 5 is a cross-sectional side view of the sensor of FIG. 4. [Figure 6] FIG. 13 is a perspective view of a sensor according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0007] Exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying Figures 1 to 6, in which like reference numerals refer to like elements. However, the present disclosure may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will convey the concept of the present disclosure to those skilled in the art. In addition, in the following detailed description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, it will be apparent that one or more embodiments can be implemented without these specific details.
[0008] Throughout Figures 1-6, only one of multiple identical elements may be labeled in the figures for clarity of the drawings, but the detailed description of the elements herein applies equally to each of the elements appearing identically in the figures. Throughout the specification, directional descriptors such as "height-wise," "longitudinal," and "width-wise" are used. These descriptors are merely for clarity of description and differentiation of various directions. These directional descriptors do not suggest or require any particular orientation of the disclosed elements.
[0009] A sensor 10 according to one embodiment is shown in Figures 1 to 3. The sensor 10 includes a housing 100, a plurality of diaphragms 200 disposed in the housing 100, and a package 400 attached to the housing 100.
[0010] The housing 100 includes a body 110 having a first surface 112 and a second surface 114 opposite the first surface 112 in a height direction H, as shown in FIGS. 1-3. The body 110 has a number of recesses 116 in the second surface 114 and a number of cavities 118 in the second surface 114. In the embodiment shown, the cavities 118 extend deeper into the second surface 114 in the height direction H than the recesses 116. In the embodiment shown, the body 110 has a generally rectangular shape. In other embodiments, the body 110 may have a different polygonal shape.
[0011] As shown in FIG. 3, the housing 100 has a plurality of passages 120 extending through the body 110. Each of the passages 120 extends from the first surface 112 through the body 110 in a height direction H. The passages 120 include a pair of first passages 122 disposed closer to the center of the body 110 in a longitudinal direction L perpendicular to the height direction H, and a pair of second passages 124 disposed closer to the exterior of the body 110 in the longitudinal direction L. The first passages 122 terminate at the second surface 114 of the body 110 and are each surrounded by one of the recesses 116 of the second surface 114, as shown in FIGS. 2 and 3. The second passages 124 terminate at one end in a cavity 118 extending into the second surface 114 of the body 110 and communicate with the cavity 118.
[0012] 1-3, the housing 100 has a plurality of ports 130 extending from the first surface 112 of the body 110. The ports 130 include a first port 132 and a second port 134 that are separated from one another along the longitudinal direction L and define separate ports 132 and 134 that protrude from the body 110 in a height direction H. The passages 120 communicate with the ports 130, and one end of one of the first passages 122 and one end of the second passages 124, opposite the second surface 114, open into each of the ports 132 and 134.
[0013] In the embodiment shown, the housing 100 is integrally formed from a single piece of metallic material. In other embodiments, the housing 100 may be formed from multiple pieces and assembled together to form the elements of the housing 100 described above. In other embodiments, the housing 100 may be formed from a non-metallic conductive material, or may be formed from a non-conductive material, such as a ceramic or plastic.
[0014] As shown in FIG. 3, the diaphragms 200 are disposed in the ports 130 of the housing 100. The diaphragms 200 are each formed of an elastically flexible material. The elastically flexible material of the diaphragms 200 may be a thin metallic material, such as stainless steel, or other conductive or non-conductive flexible material capable of transmitting forces as described in more detail below. The diaphragms 200 may be planar elements or, as in the embodiment shown, may have a corrugated cross-sectional shape. The diaphragms 200 include a first diaphragm 210 disposed in the first port 132 and a second diaphragm 220 disposed in the second port 134. The diaphragms 210 and 220 may be attached to the ports 132 and 134 by welding or any other form of attachment. The diaphragms 200 are flush with each other in the plane P.
[0015] 1-3, the package 400 includes a substrate 410, a sensor die 420 attached to the substrate 410, and a cover 440 attached to the substrate 410. The cover 440 and the substrate 410 define a sealed containment space 450 in which the sensor die 420 is disposed. The cover 440 is a solid, opaque member, although it is shown as semi-transparent in FIGS. 2 and 3 to facilitate illustration of the sealed containment space 450 of the package 400.
[0016] 1-3, the substrate 410 is a hybrid ceramic circuit, or printed circuit board, that includes a plurality of contact pads 412 and a plurality of traces 414 that electrically connect the contact pads 412 to the sensor die 420. In the embodiment shown, the contact pads 412 are arranged along the substrate 410 in a width direction W perpendicular to a height direction H and a length direction L. In the embodiment shown, the substrate 410 has a plurality of substrate passages 416 that extend through the substrate 410 along the height direction H, as shown in FIG.
[0017] As shown in Figures 2 and 3, the sensor die 420 is attached to the substrate 410 and disposed in the sealed containment space 450. In the illustrated embodiment, the sensor die 420 is a MEMS pressure sensor and has a membrane 422 that is capable of elastically deflecting in response to pressure. In one embodiment, the membrane 422 is capable of deflecting in response to pressure on both sides of the membrane 422 and is a differential pressure sensor. In another embodiment, the membrane 422 is capable of deflecting in response to pressure on one side of the membrane 422 and is an absolute pressure sensor. In a further embodiment, the sensor die 420 has a pair of membranes 422, one membrane serving as a differential pressure sensor and the other membrane serving as an absolute pressure sensor. The sensor die 420 is attached to the substrate 410 over one of the substrate passages 416.
[0018] 2 and 3, the sensor package 400 includes an integrated circuit 430, such as an application-specific integrated circuit (ASIC), mounted on a substrate 410 and electrically connected to a sensor die 420 and contact pads 412 by traces 414. The integrated circuit 430 is disposed in a sealed containment space 450 along with the sensor die 420. The integrated circuit 430 processes the electrical output signal from the sensor die 420 to determine the differential and / or absolute pressure sensed by the sensor die 420.
[0019] The cover 440 shown in FIGS. 1-3 is attached to the substrate 410 to create a sealed containment space 450. The cover 440 may be made of a ceramic material, a metal material, a plastic material, or any combination thereof. The cover 440 may be attached to the substrate 410 by any method that defines and fluid-tightly seals the sealed containment space 450 at the interface between the cover 440 and the substrate 410, such as an adhesive such as an epoxy, solder, brazing, or welding. In the position where the cover 440 is attached to the substrate 410 to create the sealed containment space 450, the contact pads 412 of the substrate 410 are disposed outside the sealed containment space 450, as shown in FIGS. 1 and 2.
[0020] As shown in FIGS. 1-3, to assemble the sensor 10, the package 400 is attached to the housing 100. The substrate 410 of the package 400 is attached to the second surface 114 of the body 110 by, for example, an adhesive such as epoxy, solder, brazing, or welding. A material for attaching the substrate 410 to the second surface 114 may be disposed in the recess 116 of the second surface 114. When the substrate 410 is attached to the second surface 114, as shown in FIG. 3, the plurality of substrate passages 416 are each aligned with one of the first passages 122 along the height direction H and communicate with the first passages 122. As described above, the cover 440 attached to the substrate 410 is disposed on the substrate 410 on the side opposite the second surface 114.
[0021] 3, the oil 700 is placed in the cavity 118 of the second surface 114, filling the second passage 124, the oil 700 fills the ports 132 and 134 held by the diaphragms 210 and 220, and fills the first passage 122 that communicates with the second passage 124 through the ports 132 and 134. The oil 700 further flows through the first passage 122, through the substrate passage 416, and into the sealed accommodation space 450, filling the sealed accommodation space 450 around the sensor die 420 and the integrated circuit 430. A passageway seal 800 is disposed in each of the cavities 118 to close the second passageway 124 and contain the oil 700 in the sensor 10 when the oil 700 is disposed in the ports 132 and 134, the passageways 122 and 124, and the sealed containment space 450. In one embodiment, the passageway seals 800 are a glass material that forms a glass-to-metal bond with the housing 100. In other embodiments, a different incompressible liquid may be used in place of the oil 700.
[0022] As shown in FIG. 3, during the use of the sensor 10 to measure pressure, the sensor 10 is exposed to, for example, a first pressure R1 and a second pressure R2. The first pressure R1 acts on the first diaphragm 210 at the first port 132. The first diaphragm 210 deflects in proportion to the first pressure R1 and correspondingly transmits the first pressure R1 to the oil 700 in the first passage 122 and the oil 700 in the substrate passage 416 that communicates with the first passage 122. The oil 700 in the substrate passage 416 that is connected to the first port 132 applies the first pressure R1 to the first surface of the membrane 422 of the sensor die 420. The second pressure R2 acts on the second diaphragm 220 at the second port 134. The second diaphragm 220 deflects in proportion to the second pressure R2 and correspondingly transmits the second pressure R2 to the oil 700 in the first passage 122 connected to the second port 134, through one of the substrate passages 416, and to the sealed containment space 450. The oil 700 in the sealed containment space 450 applies the second pressure R2 to the second surface of the membrane 422 of the sensor die 420.
[0023] In one embodiment, the membrane 422 deflects in response to a pressure difference between the first pressure R1 and the second pressure R2. The deflection of the membrane 422 generates an electrical signal representative of the pressure difference across the membrane 422. In other embodiments, the membrane 422 may alternatively or additionally deflect in response to only the first pressure R1 on one side of the membrane 422 and generate an electrical signal representative of absolute pressure. The electrical signal may be output externally from the sensor 10 through contact pads 412 of the substrate 410 by an integrated circuit 430 connected to the sensor die 420.
[0024] Another embodiment of the sensor 10 is shown in Figures 4 and 5. Like reference numerals refer to like elements and differences from the embodiment shown in Figures 1 to 3 will mainly be described in detail.
[0025] In the embodiment of the housing 100 shown in Figures 4 and 5, as shown in Figure 5, the body 110 does not have the recess 116 of the embodiment of Figure 2, but only has a pair of cavities 118 extending into the second surface 114. The passageway 120 in the embodiment of Figures 4 and 5 includes only a plurality of first passageways 122 extending along the height direction H. Each of the first passageways 122 is connected between one of the ports 132 and 134 and one of the cavities 118.
[0026] The sensor 10 according to the embodiment of Figures 4 and 5 has a package 500 including a pair of substrates 510. Each of the pair of substrates 510 has a sensor die 520 or a sensor die 530 attached thereto. The substrates 510 each have a base 512 and a flange 514 extending from the base 512. The substrates 510 each have a number of substrate passages 516 extending through the substrate 510 along a height direction H. In the embodiment of Figures 4 and 5, the substrates 510 each are solid materials without circuitry, such as a ceramic material, a metal material, a plastic material, or any combination thereof.
[0027] As shown in FIG. 5, the sensor die 520 and the sensor die 530 are each attached to one base 512 of the substrate 510. In the embodiment shown, the sensor die 520 and the sensor die 530 are each a MEMS pressure sensor and have a membrane 522 or a membrane 532 that can elastically deflect in response to pressure. In the embodiment shown, the first sensor die 520 has a first membrane 522 that can deflect in response to pressure on both sides of the first membrane 522 and is a differential pressure sensor. In the embodiment shown, the second sensor die 530 has a second membrane 532 that can deflect in response to pressure on one side of the membrane and is an absolute pressure sensor. In other embodiments, the sensor die 520 and the sensor die 530 may be arranged opposite to the embodiment shown, or both the membrane 522 and the membrane 532 may be on one of the dies 520 and 530.
[0028] The package 500 has a number of pins 550 that extend through the substrate passages 516 of each substrate 510 and are electrically connected to the first sensor die 510 or the second sensor die 530. As shown in FIG. 5, the pins 550 are located in only a portion of the substrate passages 516 of each substrate 510. The pins 550 are each a conductive material capable of transmitting an electrical signal output by the sensor die 510 and the sensor die 530. The pins 550 are sealed to the substrate passages 516 by a sealing material 560. In one embodiment, the sealing material 560 is a glass material that forms a glass-to-metal bond with the substrate 510. In other embodiments, the sealing material 560 may be any other material capable of sealing the conductive pins 550 to the substrate passages 516.
[0029] 5, to mount the package 500 to the housing 100, the substrates 510 are each disposed over one of the cavities 118 on the second side 114 of the body 110 with the flange 514 disposed on the second side 114 and the base 512 extending into the cavity 118. The flange 514 is attached to the second side 114 for fastening the substrates 510 to the housing 100 with, for example, an adhesive such as epoxy, solder, brazing, or welding. The substrates 510 each form a sealed accommodation space 570 with the body 110, the sealed accommodation space 570 being defined in each of the cavities 118. The sensor die 520 and the sensor die 530 are each disposed in one of the sealed accommodation spaces 570.
[0030] The package 500 includes a tube 540 having a pair of opposite ends, each disposed in one of the substrate passages 516 of one of the substrates 510, shown in Figures 4 and 5. The tube 540 is sealed to each of the substrates 510 by a sealing material 560. The tube 540 fluidly connects a sealed containment space 570 formed by one of the substrates 510 to a sensor die 520 on the other of the substrates 510.
[0031] With the package 500 attached to the housing 100 as shown in Figures 4 and 5, the sensor 10 is filled with oil 700. The oil 700 is placed in one of the board passages 516 of each board 510 that does not have a pin 550 or a tube 540, and fills the sealed accommodation space 570. The oil 700 flows from the sealed accommodation space 570 through the passage 120 of the housing 100 to the port 130 where the oil 700 is held by the diaphragm 200. The oil 700 further fills the tube 540 from one of the sealed accommodation spaces 570. When the oil 700 is filled, a passage seal 800 is placed in one of the board passages 516 used to contain the oil 700, and the oil 700 is contained in the sensor 10. In other embodiments, a different incompressible liquid may be used instead of the oil 700.
[0032] 4 and 5 to measure pressure, the first diaphragm 210 deflects in proportion to the first pressure R1 and correspondingly transmits the first pressure R1 through one of the passages 120 to one of the sealed containment spaces 570 having the first sensor die 520, applying the first pressure R1 to a first surface of the first membrane 522 of the first sensor die 520. The second pressure R2 acts on the second diaphragm 220 of the second port 134, which deflects in proportion to the second pressure R2 and transmits the second pressure R2 through one of the passages 120 to one of the sealed containment spaces 570 having the second sensor die 530. The second pressure R2 in the sealed containment space 570 acts on one surface of the second membrane 532 of the second sensor die 530. The second pressure R 2 is further transmitted through the tube 540 and acts on a second surface of the first membrane 522 of the first sensor die 520 .
[0033] 4 and 5, the first membrane 522 deflects in response to a pressure difference between a first pressure R1 and a second pressure R2. The deflection of the first membrane 522 generates an electrical signal representative of the pressure difference in the sealed containment volume 570 acting on either side of the first membrane 522. The second membrane 532 deflects in response to a second pressure R2 acting on one side of the second membrane 532, generating an electrical signal representative of the absolute pressure in one side of the sealed containment volume 570. The electrical signals of both the second die 520 and the second die 530 are output from the sensor 10 to the outside by sending them along the pins 550.
[0034] Another embodiment of the sensor 10 is shown in Figure 6. Like reference numerals refer to like elements and differences from the embodiment shown in Figures 1-3 will be mainly described in detail. The package 400 of the embodiment of Figures 1-3 is shown diagrammatically in Figure 6 for clarity of illustration, but has the same structural details and positions as described above with respect to Figures 1-3.
[0035] 6 embodiment of the sensor 10 includes a third port 136 in the housing 100 and a third diaphragm 230 disposed in the third port 136 in a manner similar to that described above. The third port 236 includes another set of passages 120, including the first passages 122 and the second passages 124 described above. The other set of passages 120 connect to the third port 136 and communicate with the second face 114 of the body 110.
[0036] 6, the sensor 10 has another package 600 disposed on the second face 114 over the first passage 122 connected to the third port 136. The package 600 has a substrate 610, a sensor die 620 disposed on the substrate 610, and a number of sidewalls 630 extending from the substrate 610 around the sensor die 620. The substrate 610 and the sidewalls 630 define a sealed containment space 632 around the sensor die 620 that is filled with a gel 634.
[0037] 6, the sensor die 420 of the package 400 senses the differential and / or absolute pressure of the pressures R1 and R2 as described above. As described above, the third pressure R3 acting on the third diaphragm 230 is transmitted through the oil, through the first passage 122, and through the substrate passage 612 of the substrate 610 to the sensor die 620. The third pressure R3 deflects one side of the diaphragm 622 of the sensor die 620, and the sensor die 620 can measure the absolute pressure of the third pressure R3.
[0038] The sensor 10 according to the embodiment of Figure 6 may further include a temperature probe 900 disposed on and extending from the housing 100. The temperature probe 900, such as a thermocouple, may measure the temperature proximate the sensor 10, which may be used to improve the accuracy of the pressure signal output by the sensor 10.
[0039] 1-6, the use of packages 400, 500, 600 containing sensor die 420, 520, 530, 620 on substrate 410, 510, 610, and attachment of packages 400, 500, 600 to housing 100 facilitates manufacturing of sensor 10 by simplifying placement of sensor die 420, 520, 530, 620 and connection to oil 700. Additionally, locating integrated circuit 430 in close proximity to sensor die 420 within oil 700 improves signal processing.
Claims
1. A sensor (10), a housing (100) having a body (110) and a plurality of ports (130), said body (110) having a first side (112) and an opposing second side (114), said ports (130) extending from said first side (112) of said body (110); a plurality of diaphragms (200) each disposed in one of the ports (130); a package (400, 500, 600) having a substrate (410, 510, 610) and a sensor die (420, 520, 530, 620) attached to the substrate (410, 510, 610), the substrate (410, 510, 610) being attached to the second surface (114) of the body (110), the sensor die (420, 520, 530, 620) being disposed in an enclosed containment space (450, 570, 632) partially defined by the substrate (410, 510, 610); A sensor (10).
2. The sensor (10) of claim 1, wherein the diaphragms (200) are coplanar with one another.
3. 2. The sensor (10) of claim 1, wherein the package (400) has a cover (440) attached to the substrate (410) on a side of the substrate (410) opposite the second surface (114) of the body (110), and the cover (440) and the substrate (410) define the sealed storage space (450).
4. 4. The sensor (10) of claim 3, wherein the body (110) has a plurality of passages (120) extending therethrough, the passages (120) communicating with the port (130), and the substrate (410) has a plurality of substrate passages (416) extending therethrough, the passages (120) of the body (110) including a plurality of first passages (122) communicating with the substrate passages (416).
5. The sensor (10) of claim 4, wherein the sensor die (420) is disposed over one of the substrate passages (416), the sensor die (420) having a deflectable membrane (422).
6. 5. The sensor (10) of claim 4, wherein the body (110) has a plurality of cavities (118) extending into the second surface (114), the passage (120) of the body (110) includes a plurality of second passages (124) in communication with the cavities (118), and the sensor (10) further comprises a passage seal (800) disposed in each of the cavities (118) and closing the second passages (124).
7. The sensor (10) of claim 4, wherein the package (400) comprises an integrated circuit (430) disposed in the sealed containment volume (450) and connected to the sensor die (420).
8. The sensor (10) of claim 1, wherein oil (700) is contained in the port (130) and the enclosed containment space (450, 570, 632).
9. 2. The sensor (10) of claim 1, wherein the body (110) has a cavity (118) extending into the second surface (114), the substrate (510) is attached to the second surface (114) over the cavity (118), and the sealed containment space (570) is defined by the substrate (510) and the body (110).
10. 10. The sensor of claim 9, wherein the substrate has a base and a flange extending from the base, the flange being attached to the second surface of the body, and the base extending into the cavity.
11. 10. The sensor of claim 9, wherein the body has a passage extending therethrough and connecting one of the ports to the enclosed containment volume.
12. The sensor (10) of claim 9, wherein the package (500) has a plurality of pins (550) extending through the substrate (510) and electrically connecting to the sensor die (520, 530).
13. 10. The sensor (10) of claim 9, wherein the cavity (118) is one of a plurality of cavities (118) extending into the second surface (114), the substrate (510) is one of a plurality of substrates (510) of the package (500), each of the substrates (510) being attached to the second surface (114) over one of the cavities (118) to define a plurality of sealed accommodation spaces (570), and the sensor (10) further comprises a tube (540) extending between the substrates (510).
14. 14. The sensor (10) of claim 13, wherein the package (500) has a pair of sensor dies (520, 530) each attached to one of the substrates (510), a first sensor die (530) of the sensor dies (520, 530) measuring an absolute pressure of one of the sealed containment spaces (570) and a second sensor die (520) of the sensor dies (520, 530) measuring a differential pressure between the sealed containment spaces (570).
15. 2. The sensor of claim 1, wherein the package includes a plurality of sidewalls extending from the substrate to define the sealed containment space, and a gel disposed about the sensor die in the sealed containment space.