WO2013006167A1 - Puce de capteur - Google Patents

Puce de capteur Download PDF

Info

Publication number
WO2013006167A1
WO2013006167A1 PCT/US2011/042999 US2011042999W WO2013006167A1 WO 2013006167 A1 WO2013006167 A1 WO 2013006167A1 US 2011042999 W US2011042999 W US 2011042999W WO 2013006167 A1 WO2013006167 A1 WO 2013006167A1
Authority
WO
WIPO (PCT)
Prior art keywords
axis
cavity
sensor
stress isolation
diaphragm
Prior art date
Application number
PCT/US2011/042999
Other languages
English (en)
Inventor
Ron B. Foster
Original Assignee
Foster Ron B
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Foster Ron B filed Critical Foster Ron B
Priority to PCT/US2011/042999 priority Critical patent/WO2013006167A1/fr
Publication of WO2013006167A1 publication Critical patent/WO2013006167A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
    • G01L19/14—Housings
    • G01L19/145—Housings with stress relieving means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
    • G01L19/14—Housings
    • G01L19/147—Details about the mounting of the sensor to support or covering means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
    • G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
    • G01L9/0042—Constructional details associated with semiconductive diaphragm sensors, e.g. etching, or constructional details of non-semiconductive diaphragms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805—Shape
    • H01L2224/4809—Loop shape
    • H01L2224/48091—Arched

Definitions

  • the present invention relates to sensor die that are electrically and
  • Sensor die may comprise pressure sensor, microphone, gyroscope, or accelerometer die.
  • High performance sensor die maintain small measurement error as a percentage of output voltage over wide temperature range and long operating life.
  • Common elements include a diaphragm that may be round, square, or rectangular in shape, having sidelength (or diameter) to thickness ratio of roughly 20 - 200. For most silicon manufacturers, minimum diaphragm thickness is in the range of .005 - .020 mm. Surrounding the diaphragm is a relatively stiff constraint region that deflects minimally in response to applied pressure.
  • the diaphragm deflects proportionally to a difference in pressure on the top and bottom of the diaphragm.
  • Various sensing components have been applied to extract an output voltage that is relatively linearly related to the diaphragm deflection, and hence to the applied pressure.
  • piezoresistive and capacitive sensing components have been widely applied.
  • Nominal design diaphragm thickness is limited by manufacturing variability. For example, with electrochemical etch stop, any leakage currents across a given wafer result in debiasing and localized variation in the stopping potential. Such leakage currents lead to variability in diaphragm thickness of perhaps +/- .001 mm. A reasonable diaphragm thickness tolerance is +/- 20% about nominal. Therefore, for this example manufacturing method, the minimum nominal design diaphragm thickness is about .005 mm.
  • Sensor die cost is roughly proportional to die area. For a pressure sensor die, the output voltage in response to applied pressure is approximately proportional to the square of the ratio of diaphragm sidelength to thickness regardless of the sensing components used.
  • diaphragm sidelength-to-thickness ratio For sensing at lower full-scale applied pressure, larger diaphragm sidelength-to-thickness ratio is required to maintain a given output voltage. Since diaphragms are subject to a minimum thickness due to manufacturing constraints, larger sidelength-to-thickness ratio dictates increasingly larger diaphragm size as full-scale applied pressure decreases. In turn, die size and cost is increased as full-scale applied pressure is decreased.
  • the minimum die size is defined by the size of the diaphragm plus
  • a 10 kPa full scale sensor die might have a diaphragm sidelength of 1 .0 mm, diaphragm thickness of 0.01 mm. With a constraint region width of 0.15 mm, the minimum die size prior to dicing is then 1 .3 X 1 .3 mm.
  • wet anisotropic silicon etch to form diaphragms. As frequently applied, this etch procedure produces sidewalls angled at 54.74 degrees. Die size must be further increased to accommodate this slope.
  • DRIE deep reactive ion etch
  • etching through the almost entire thickness of the wafer as typically required to produce a diaphragm, the cost of DRIE is often considered to be prohibitive.
  • a solution applying DRIE to produce vertical diaphragm sidewalls might lead to reduced die cost if, for example, the required thickness of silicon to be etched is less than about 20% of the entire thickness of the wafer.
  • a first line of defense is to mechanically connect to the bottom, or back, of the die, as far away as possible from the sensitive diaphragm.
  • a stress buffering element between the silicon die and the port to which the die is mounted is a common approach to further isolate mounting stresses when the mechanical interconnection is to the bottom, or back, of the silicon die.
  • an anodically bonded borosilicate glass isolator is often applied.
  • isolators significantly reduce coupling of mounting stress into the sensitive diaphragm, the cost is substantially increased.
  • inclusion of an isolator often leads to doubling or tripling the overall thickness of the mounted die.
  • singulation by dicing is much more difficult and costly when using a thick glass isolator.
  • the port is formed of a metal alloy having a CTE that is substantially larger than the silicon CTE.
  • soft adhesion layer materials are often used to attach the die on isolator to the port.
  • RTV room temperature vulcanizing
  • Epoxies, solders, eutectic alloys, and fritted glass are representative of mechanically hard adhesion layer materials. Such materials undesirably couple mounting stresses arising from CTE mismatch between the port, isolator and the die into the sensitive diaphragm portion of the sensor die.
  • hard adhesion layer materials may themselves introduce stresses that affect the diaphragm.
  • the elastic constants of epoxy are known to change over operating life, while solders are subject to creep over temperature and operating life.
  • there are significant motivations to apply such hard mount adhesion layer materials For example, application of epoxy is desired for ease of assembly and for cost reduction. Application of solder or eutectic alloy is desired for hermetic applications. An approach is needed that accommodates an adhesion layer formed of hard materials without resulting in undue coupling of mounting stresses to the sensitive sensor die diaphragm.
  • a drawback common to various circuits formed of sensing components is that a non-zero electrical output voltage, termed an offset voltage, is seen at the output terminals.
  • the offset voltage is undesirable at room temperature, since it complicates sensor calibration.
  • the offset voltage also changes with temperature, partially due to CTE mismatch.
  • TCO temperature change in offset
  • the specified device operating temperature range is often limited primarily by TCO considerations.
  • Reproducible changes in offset voltage over temperature and non-reproducible changes in offset voltage over operating life together establish critical limitations on performance. It is difficult to correct for both of these error sources over operating life. And, it is well established empirically that as die size is decreased, performance as limited by TCO becomes steadily worse. But, there is a need for sensor die having both reduced die size and high performance. For high performance, both room temperature offset voltage and TCO must be minimized.
  • the isolator material is borosilicate glass as opposed to silicon.
  • the CTE mismatch between silicon and borosilicate glass leads to increased TCO.
  • the result is an expensive isolator that itself introduces mismatch stresses over temperature.
  • the cantilever approach has merit, but there is a need for an inventive approach that simultaneously reduces cost and minimizes coupling of mounting stresses.
  • a pressure sensor module incorporates a platform providing stress isolation to a pressure sensing element.
  • This patent does not teach how to make a sensing element. From the specification and drawings it appears that the sensing element does not involve a diaphragm. And, it appears that there are no fluid conduits associated with the sensing element.
  • U.S. Patent No. 7,635,077 a method of flip-chip mounting pressure sensor die to a substrate is taught. The method makes no provision for stress isolation. A low-cost method of manufacturing pressure sensors suitable for price sensitive applications is provided, without regard to performance in terms of measurement error. To those skilled in the art it will be obvious that this method results in unacceptably high measurement error for the majority of applications. There is a need for a flip-chip mounting approach that simultaneously reduces cost and maintains or improves on established performance.
  • the invention enables integration of multiple stress isolation features into a single, silicon-based, sensor die, thereby eliminating the need for a separate isolator.
  • the invention is directed to a sensor comprising a sensor die, the die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a cavity disposed between the first and second surfaces, wherein the cavity is proximate the first end of the first axis;
  • a diaphragm capping the cavity; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic communication with the cavity; a substrate proximate to the second surface; an adhesion layer mechanically bonding the second surface to the substrate, wherein the adhesion layer is nearer the second end of the first axis than the first end of the first axis and wherein the adhesion layer does not extend beneath the diaphragm; and a sensing component disposed on or proximate to the diaphragm, wherein the sensing component is connected in signal communication with an external circuit.
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a cavity disposed between the first and second surfaces, wherein the cavity is proximate the first end of the first axis; a diaphragm capping the cavity; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic
  • a substrate proximate to the second surface; an adhesion layer mechanically bonding the second surface to the substrate, wherein the adhesion layer is nearer the second end of the first axis than the first end of the first axis and wherein the adhesion layer does not extend beneath the diaphragm; a sensing component disposed on or proximate to the diaphragm; an electronic circuit connected to the sensing component; and an external circuit electrically connected to the electronic circuit.
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a first cavity disposed between the first and second surfaces, wherein the first cavity is proximate the first end of the first axis; a diaphragm capping the first cavity; a second cavity disposed between the first and second surface to form a chamber, wherein the chamber is proximate a second end of the first axis; a channel disposed between the first and second surface, wherein the channel connects the first cavity and the chamber whereby fluid may flow therebetween; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic communication with the first cavity
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a first cavity disposed between the first and second surfaces, wherein the first cavity is proximate the first end of the first axis; a diaphragm capping the first cavity; a second cavity disposed between the first and second surface to form a chamber, wherein the chamber is proximate the second end of the first axis; a channel disposed between the first and second surface, wherein the channel connects the first cavity and the chamber whereby fluid may flow therebetween; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic communication with the first cavity;
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a cavity disposed between the first and second surfaces, wherein the cavity is proximate the first end of the first axis; a diaphragm capping the cavity; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic
  • a substrate proximate to the first surface; an adhesion layer mechanically bonding the first surface to the substrate, wherein the adhesion layer is nearer the second end of the first axis than the first end of the first axis and wherein the adhesion layer does not extend beneath the diaphragm; and a sensing component disposed on or proximate to the diaphragm, wherein the sensing component is connected in signal communication with an external circuit.
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a cavity disposed between the first and second surfaces, wherein the cavity is proximate the first end of the first axis; a diaphragm capping the cavity; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic
  • a substrate proximate to the first surface; an adhesion layer mechanically bonding the first surface to the substrate, wherein the adhesion layer is nearer the second end of the first axis than the first end of the first axis and wherein the adhesion layer does not extend beneath the diaphragm; a sensing component disposed on or proximate to the diaphragm; an electronic circuit connected to the sensing component; and
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface; a first cavity disposed between the first and second surfaces, wherein the first cavity is proximate the first end of the first axis; a diaphragm capping the first cavity; a second cavity disposed between the first and second surface to form a chamber, wherein the chamber is proximate a second end of the first axis; a channel disposed between the first and second surface, wherein the channel connects the first cavity and the chamber whereby fluid may flow therebetween; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic communication with the first cavity
  • the invention is directed to a sensor comprising a sensor die, the sensor die comprising a planar first surface comprising a first axis and second axis, wherein the second axis is perpendicular to the first axis and the first axis is longer than the second axis, and wherein the first axis comprises first and second ends; a second surface adjacent to the first surface;
  • first cavity disposed between the first and second surfaces, wherein the first cavity is proximate the first end of the first axis; a diaphragm capping the first cavity;
  • a second cavity disposed between the first and second surface to form a chamber, wherein the chamber is proximate the second end of the first axis; a channel disposed between the first and second surface, wherein the channel connects the first cavity and the chamber whereby fluid may flow therebetween; and one or more stress isolation features disposed between the first and second surfaces, wherein the stress isolation features comprise cavities spaced apart from and not in fluidic communication with the first cavity; a via connecting the chamber to the first surface; a substrate proximate to the first surface, wherein the substrate comprises a port connected in fluidic communication with the via in the sensor die and a pressure source; an adhesion layer mechanically bonding the first surface to the substrate, wherein the adhesion layer is nearer the second end of the first axis than the first end of the first axis and wherein the adhesion layer does not extend beneath the diaphragm and does not extend beneath the via; a sensing component disposed on or proximate to the diaphragm; an electronic circuit connected to
  • Fig. 1A is a side cross-sectional view illustration of a conventional prior art silicon die having sloped diaphragm sidewalls and stress isolation mount.
  • Fig. 1 B is a side cross-sectional view illustration of a conventional prior art silicon die having vertical diaphragm sidewalls formed by DRIE. Stress isolation mount is included.
  • Fig. 2 is a side cross-sectional view illustration of a prior art silicon die.
  • the mechanical connection to a port is on one end of the die (right side in view), while the diaphragm is positioned on the opposite end of the die (left side in view).
  • Fig. 3A is a plan view illustration of a first embodiment of the inventive die.
  • Fig. 3B is a sectional view illustration of a first embodiment of the inventive die.
  • Fig. 4A is a plan view illustration of a second embodiment of the inventive die incorporating buried stress isolation cavities.
  • Fig. 4B is a sectional view illustration of a second embodiment of the inventive die incorporating buried stress isolation cavities.
  • Fig. 4D is a plan view illustration of a second embodiment of the inventive die where connecting channel is serpentine and coarse-feature buried stress isolation cavities are included.
  • Fig. 5A is a plan view illustration of a third embodiment of the inventive die including top-down stress isolation slots.
  • Fig. 5C is a plan view illustration of a third embodiment of the inventive die including both top-down stress isolation slots and bottom-up stress isolation slots.
  • Fig. 5D is a side view illustration of a third embodiment of the inventive die including both top-down stress isolation slots and bottom-up stress isolation slots.
  • Fig. 6B is a side view illustration of a fourth embodiment of the inventive die incorporating flip-chip die attach and multiple stress isolation features, optionally including top-down stress isolation slots, bottom-up stress isolation slots, and buried stress isolation cavities.
  • Fig. 7A is a plan view illustration of a fifth embodiment of the inventive die incorporating backstops.
  • Fig. 7B is a sectional view illustration of a fifth embodiment of the inventive die incorporating backstops.
  • a buried cavity beneath diaphragm and optionally buried cavities comprising connecting channel and chamber are defined with a single photomask and DRIE step.
  • electrical connections are formed to the first, or top, surface of the sensor die. For example, conventional wire bonding may be applied.
  • Mechanical connections are made to the second, or bottom, surface of the sensor die. Since the sensitive diaphragm region is
  • additional stress isolation features comprised of slots cut into either the top surface, bottom surface, or both top and bottom surfaces may be included in order to reduce lateral coupling of stresses into the diaphragm region.
  • a second embodiment is similar to the first embodiment, with the addition of buried stress isolation cavities. Integration of buried cavities designed to further improve isolation of mounting stresses is accomplished by simply adding features to the photomask used during the DRIE step, with no added cost relative to the first embodiment.
  • a third embodiment is similar to the second embodiment, with the addition of top-down isolation slots, bottom-up isolation slots, or both top-down and bottom-up isolation slots formed in both first and second surfaces of the sensor die to further improve isolation of mounting stresses.
  • the invention enables flip-chip mounting of sensor die while maintaining performance meeting a majority of application requirements.
  • the sensor die is flip-chip mounted with both the electrical, the mechanical and optionally the fluidic connections made to the first, or top, surface of the die.
  • An electrically conductive adhesion layer is used to mechanically attach the sensor die to the port. Electrically isolated portions of said electrically conductive adhesion layer form electrical connections to each of several circuit interconnect pads on the die. It is understood that slots may optionally be cut into either the first surface, second surface, or both first and second surfaces to optimize mounting stress isolation and cost for a given application. Integration of stress isolation features enables flip-chip mounting to a port without incurring increased measurement error.
  • the thickness of the second wafer is then reduced to a target value equal to a planned diaphragm thickness.
  • portions of the device layer formed by thinning the second wafer cover all of the buried cavities.
  • the portion of the device layer covering the largest cavity is termed a diaphragm.
  • connecting channels leading from the cavity beneath the diaphragm to a port-connecting chamber and the chamber itself are formed simultaneously with other cavities.
  • Stress isolation cavities may be formed simultaneously with the buried cavity beneath the diaphragm by simply adding features to a photomask.
  • the various functions of diaphragm, connecting channel, chamber and stress isolation cavities are provided by a single preparation procedure on a sensor wafer.
  • Some non-uniformity in the device layer thickness results from thinning of the second wafer. Such non-uniformity may be minimized by maintaining a sidelength to thickness ratio of no more than 40:1 for all features.
  • a layer transfer technique well known to those skilled in the arts, may be applied to obtain sidelength to thickness ratios much greater than 40:1 while maintaining acceptable thickness uniformity.
  • diaphragm thickness of 0.002 mm is achievable using
  • diaphragm thickness variation can be controlled to within +/- .0005 mm of target value by use of these methods.
  • device layer thickness may be reduced to a few nanometers.
  • Some care is required to ensure that all features formed by device layer over buried cavities are sufficiently robust to enable follow-on fabrication.
  • the continuity of buried cavities may be interrupted to include supporting posts. As is well known to those skilled in the arts, such supporting posts may be designed to provide diaphragm backstop, which enhances robustness.
  • the sidelength can be reduced, resulting in smaller die.
  • the die size might be reduced to 0.5 X 0.5 mm.
  • both the constraint width and thickness should be at least about 3 times the diaphragm thickness, and preferably at least about 10 times the diaphragm thickness. Therefore, for a diaphragm thickness of .002 mm, the constraint width may comfortably be reduced to .05 mm.
  • a rectangular die sized 0.3 X 0.5 mm may meet all requirements. In this case, the chamber and via connecting to the port may be limited to about 0.1 mm diameter.
  • Interconnect metal and pads typically enable electrical connection, but may also include, for example, an annular ring about the port to make fluidic and mechanical connection. Those skilled in the arts will recognize that many alternative procedures are satisfactory to form such sensing components and interconnect.
  • added circuit elements may include resistors, capacitors, inductors, transistors, and isolation regions.
  • resistors may include resistors, capacitors, inductors, transistors, and isolation regions.
  • circuit elements along with associated interconnect metal and pads are known to comprise an integrated circuit.
  • a first, optional photopattern and DRIE step is included to form slots extending from the first, or top, surface towards the second, or back, surface.
  • the DRIE is targeted to remove .002 - .400 mm of silicon thickness in the areas not protected by photoresist.
  • a second, optional, photopattern and etch step is included to form a fluidic connection between the chamber and the second, or bottom, surface of the die.
  • the wafer can proceed to electrical test and singulation.
  • the first, slot-creating, photopattern and etch step can fulfill multiple purposes.
  • silicon can be substantially removed as required to create a via bringing the chamber into fluidic communication with the port.
  • coupling of mounting stresses into the diaphragm portion can be further reduced, both at ambient temperature and across the specified temperature range, by incorporation of slots.
  • die can be partially or totally singulated by etching in the dicing lanes.
  • the second, chamber-connecting, photopattern and etch step can also fulfill multiple purposes.
  • the step can complete any removal as required to bring the chamber into fluidic communication with the port.
  • additional slots may be created on the second, or bottom, surface of the die, to further reduce coupling of mounting stresses.
  • die again die can be partially or totally singulated by etching in the dicing lanes.
  • interconnect pads may optionally be selectively coated with a material that meets the requirements for both electrical and mechanical interconnections.
  • conductive epoxy may be applied by screen printing methods, covering interconnect pads and forming an annular ring about the port.
  • Fig. 3A is a plan view
  • Fig. 3B a sectional view illustrating a first embodiment of a die according to the present invention.
  • diaphragm 320, connecting channel 330, and chamber 335 are simultaneously formed during wafer fabrication photolithography and deep reactive ion etch (DRIE) steps.
  • silicon layer 300 is formed by direct silicon fusion bond of a second wafer followed by thinning. Thickness of silicon layer 300 establishes the thickness of diaphragm 320.
  • conduit 305 is formed by photolithography and DRIE step. It is understood that the photopattern used to form conduit 305 is carefully aligned to chamber 335 using industry standard methods.
  • silicon die 310 is mounted to port 315 using adhesion layer 380. Conduit 305 connects chamber 335 to port 315 allowing for coupling of pressure to connecting channel 330 and hence to diaphragm 320.
  • adhesion layer 380 mounting is positioned on the opposite end of silicon die 310 from diaphragm 320, allowing for isolation of mounting stresses.
  • the inventive approach results in significant cost (size) reduction both by incorporation of vertical diaphragm sidewalls and by elimination of the requirement for specialized epitaxial layers and a separate isolator formed of borosilicate glass.
  • the all-silicon construction results in perfect matching of expansion coefficients over temperature.
  • Port 315 includes conductive traces 350. Electrical connection between conductive traces 350 and circuit interconnect pads 340 on silicon die 310 are formed by wire bonds 360.
  • conductive traces 350 may alternately be formed on a secondary structure, for example a printed circuit board, with wire bonds 360 connecting circuit interconnect pads 340 to said secondary structure. Although not shown, it is further understood that additional conductive traces will connect circuit interconnect pads 340 to sensing components on diaphragm 320.
  • Fig. 4A is a plan view
  • Fig. 4B a sectional view of Section B - B taken from Fig. 4A, together illustrating a second embodiment of the inventive die incorporating additional stress isolation features.
  • diaphragm 400, connecting channel 410, chamber 420, and buried stress isolation cavities 430 are
  • Fig. 4E and Fig. 4F are plan views further illustrating a second embodiment of the inventive die incorporating additional stress isolation features.
  • connecting channel 450 is shown as being serpentine.
  • Fine-feature buried stress isolation cavities 470 are included. By reducing the feature width and spacing between adjacent features, a multiplicity of such cavities may be included.
  • feature widths may be as small as about .05 times feature etched depth, while feature spacing is limited by undercut to be about the same as feature width. For example, with a 0.2 mm etch depth, feature width and spacing may each be 0.01 mm.
  • Such feature size is substantially larger than typical minimum geometry as defined by photolithography limitations.
  • connecting channel 450 is serpentine, and arbitrary-shape buried stress isolation cavities 480 are included. As above, some ⁇ restrictions must be observed to minimize lateral flexing due to applied pressure.
  • FIG. 5 is an illustration of a third embodiment of the invention.
  • Fig. 5A is a plan view
  • Fig 5B a side view illustration of a third embodiment of the inventive die incorporating additional stress isolation features.
  • Top-down stress isolation slots 520 are formed in silicon layer 500 and extend into silicon substrate 510.
  • Top-down stress isolation slots 520 are formed by photolithography and DRIE. Such top-down stress isolation slots 520 further enhance stress isolation and prevent coupling of stress from the mounting platform to the sensitive diaphragm.
  • Fig. 5C is a plan view
  • Fig 5D a side view illustration of a third embodiment of the inventive die incorporating yet additional stress isolation features.
  • Top-down stress isolation slots 520 are formed in silicon layer 500 and extend into silicon substrate 510.
  • Top-down stress isolation slots 520 are formed by a first
  • solder does not form a hermetic seal.
  • Hermetic materials are required in some applications.
  • Solder and eutectic alloys in general are higher cost alternative flip-chip attachment materials that are hermetic.
  • solderable metal must be applied to both the die and the port.
  • solder exhibits thermal hysteresis and tends to creep with time. In fact, usage of solder mounting without addition of the inventive lateral isolation features would result in significantly reduced performance.
  • Formation of backstops 700 requires an additional photolithography and DRIE step prior to forming buried cavities 710 and prior to fusion bonding and thinning to form silicon layer 720.
  • a first photolithography pattern would include all buried cavity features, and DRIE would be performed perhaps only .001 - .005 mm deep.
  • Said first photolithography pattern would be removed and a second photolithography pattern having all buried cavity features except for backstop 700 regions would be applied.
  • DRIE would be performed to normal target depth.
  • Wafer thinning may be completed prior to singulation as a means of further miniaturizing sensor die and further optimizing lateral stress isolation.
  • compositions and methods consisting essentially of and consisting of the recited components or elements.
  • the invention illustratively described herein suitably may be practiced in the absence of any element or elements, limitation or limitations which is not specifically disclosed herein.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Child & Adolescent Psychology (AREA)
  • Measuring Fluid Pressure (AREA)

Abstract

L'invention concerne une puce de capteur comportant au moins une cavité enfouie, couverte par un diaphragme, et qui est couplée électriquement et mécaniquement afin de produire une tension de sortie linéaire stable en réponse à une stimulation physique appliquée. La puce de capteur est formée à partir de deux surfaces assemblées, l'une des surfaces formant également la partie diaphragme en coiffant la cavité enfouie. Une connexion traversant le substrat et qui pénètre dans une chambre se situant à l'intérieur d'une surface, est mise en communication fluidique avec la cavité enfouie par un canal d'écoulement. La chambre et le diaphragme sont séparés latéralement afin d'isoler les contraintes de montage, ce qui permet d'améliorer l'efficacité du capteur. La puce de capteur peut comprendre un capteur de pression, un microphone, un gyroscope ou une puce d'accéléromètre.
PCT/US2011/042999 2011-07-06 2011-07-06 Puce de capteur WO2013006167A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US2011/042999 WO2013006167A1 (fr) 2011-07-06 2011-07-06 Puce de capteur

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2011/042999 WO2013006167A1 (fr) 2011-07-06 2011-07-06 Puce de capteur

Publications (1)

Publication Number Publication Date
WO2013006167A1 true WO2013006167A1 (fr) 2013-01-10

Family

ID=47437314

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2011/042999 WO2013006167A1 (fr) 2011-07-06 2011-07-06 Puce de capteur

Country Status (1)

Country Link
WO (1) WO2013006167A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3376194A1 (fr) * 2017-03-15 2018-09-19 Honeywell International Inc. Systèmes microélectromécaniques (mems) force capteur avec cavité ventilée aux bords
CN108622851A (zh) * 2018-04-28 2018-10-09 中科芯集成电路股份有限公司 一种带有空腔的衬底的制备方法
CN109738098A (zh) * 2018-12-29 2019-05-10 菲比蓝科技(深圳)有限公司 压力传感器及其形成方法
CN112050995A (zh) * 2019-06-06 2020-12-08 泰科电子连接解决方案有限责任公司 具有保护性压力特征的压力传感器组件
CN112050996A (zh) * 2019-06-06 2020-12-08 泰科电子连接解决方案有限责任公司 具有保护性压力特征的压力传感器组件

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5412994A (en) * 1994-06-14 1995-05-09 Cook; James D. Offset pressure sensor
US6229190B1 (en) * 1998-12-18 2001-05-08 Maxim Integrated Products, Inc. Compensated semiconductor pressure sensor
US20010001550A1 (en) * 1998-11-12 2001-05-24 Janusz Bryzek Integral stress isolation apparatus and technique for semiconductor devices
US6958285B2 (en) * 2001-02-22 2005-10-25 Tru-Si Technologies, Inc. Methods of manufacturing devices having substrates with opening passing through the substrates and conductors in the openings
US20060260408A1 (en) * 2005-05-06 2006-11-23 Stmicroelectronics S.R.L. Integrated differential pressure sensor and manufacturing process thereof
US7265429B2 (en) * 2002-08-07 2007-09-04 Chang-Feng Wan System and method of fabricating micro cavities
US7409865B2 (en) * 2005-09-30 2008-08-12 General Electric Company Diaphragm structure
US20090064790A1 (en) * 2005-12-31 2009-03-12 Corning Incorporated Microreactor Glass Diaphragm Sensors
WO2009053915A1 (fr) * 2007-10-23 2009-04-30 Sensile Pat Ag Système de détection d'écoulement de liquide
US7703339B2 (en) * 2005-12-09 2010-04-27 Analog Devices, Inc. Flow sensor chip

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5412994A (en) * 1994-06-14 1995-05-09 Cook; James D. Offset pressure sensor
US20010001550A1 (en) * 1998-11-12 2001-05-24 Janusz Bryzek Integral stress isolation apparatus and technique for semiconductor devices
US6229190B1 (en) * 1998-12-18 2001-05-08 Maxim Integrated Products, Inc. Compensated semiconductor pressure sensor
US6958285B2 (en) * 2001-02-22 2005-10-25 Tru-Si Technologies, Inc. Methods of manufacturing devices having substrates with opening passing through the substrates and conductors in the openings
US7265429B2 (en) * 2002-08-07 2007-09-04 Chang-Feng Wan System and method of fabricating micro cavities
US20060260408A1 (en) * 2005-05-06 2006-11-23 Stmicroelectronics S.R.L. Integrated differential pressure sensor and manufacturing process thereof
US7409865B2 (en) * 2005-09-30 2008-08-12 General Electric Company Diaphragm structure
US7703339B2 (en) * 2005-12-09 2010-04-27 Analog Devices, Inc. Flow sensor chip
US20090064790A1 (en) * 2005-12-31 2009-03-12 Corning Incorporated Microreactor Glass Diaphragm Sensors
WO2009053915A1 (fr) * 2007-10-23 2009-04-30 Sensile Pat Ag Système de détection d'écoulement de liquide

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108627286B (zh) * 2017-03-15 2022-01-25 霍尼韦尔国际公司 具有向边缘通气的埋置腔的微机电系统（mems）力芯片
CN108627286A (zh) * 2017-03-15 2018-10-09 霍尼韦尔国际公司 具有向边缘通气的埋置腔的微机电系统（mems）力芯片
EP3376194A1 (fr) * 2017-03-15 2018-09-19 Honeywell International Inc. Systèmes microélectromécaniques (mems) force capteur avec cavité ventilée aux bords
CN114323370B (zh) * 2017-03-15 2024-08-16 霍尼韦尔国际公司 具有向边缘通气的埋置腔的微机电系统（mems）力芯片
CN114323370A (zh) * 2017-03-15 2022-04-12 霍尼韦尔国际公司 具有向边缘通气的埋置腔的微机电系统（mems）力芯片
CN108622851A (zh) * 2018-04-28 2018-10-09 中科芯集成电路股份有限公司 一种带有空腔的衬底的制备方法
CN109738098A (zh) * 2018-12-29 2019-05-10 菲比蓝科技(深圳)有限公司 压力传感器及其形成方法
US11193842B2 (en) 2019-06-06 2021-12-07 Te Connectivity Solutions Gmbh Pressure sensor assemblies with protective pressure feature of a pressure mitigation element
EP3748325A1 (fr) * 2019-06-06 2020-12-09 TE Connectivity Solutions GmbH Ensembles capteurs de pression dotés d'une fonctionnalité de pression de protection
CN112050996A (zh) * 2019-06-06 2020-12-08 泰科电子连接解决方案有限责任公司 具有保护性压力特征的压力传感器组件
CN112050995B (zh) * 2019-06-06 2024-06-11 泰科电子连接解决方案有限责任公司 具有保护性压力特征的压力传感器组件
CN112050996B (zh) * 2019-06-06 2024-06-11 泰科电子连接解决方案有限责任公司 具有保护性压力特征的压力传感器组件
CN112050995A (zh) * 2019-06-06 2020-12-08 泰科电子连接解决方案有限责任公司 具有保护性压力特征的压力传感器组件

Similar Documents

Publication Publication Date Title
EP2653443B1 (fr) Structures MEMS isolées du stress et procédés de fabrication
EP1920229B1 (fr) Capteurs de pression et procedes de realisation
EP3364165B1 (fr) Capteur piezorésistif à flexibles de ressort pour l'isolement de contrainte
US20010001550A1 (en) Integral stress isolation apparatus and technique for semiconductor devices
JP6024481B2 (ja) 半導体圧力センサ
EP2423656A1 (fr) Capteur de pression
EP2463636A1 (fr) Adhésion augmentée d'une puce de capteur
JP2005227283A (ja) 鋼ダイヤフラム上にシリコンチップを備えた圧力センサ
WO2013006167A1 (fr) Puce de capteur
JP2009241164A (ja) 半導体センサー装置およびその製造方法
CA2975342C (fr) Capteur mems a integration de dispositifs electroniques
US8866241B2 (en) Pressure sensing device having contacts opposite a membrane
EP3260831B1 (fr) Capteur de force à faible coût
JP4847686B2 (ja) 半導体加速度センサ
JP3316555B2 (ja) 圧力センサ
JP3173256B2 (ja) 半導体加速度センサとその製造方法
JP2006506653A (ja) 圧力センサ
CN113443602B (zh) 微机电系统芯片晶圆级封装结构及其制造工艺
JP2010197286A (ja) 加速度センサ及び加速度センサの製造方法
JP2003090845A (ja) 半導体加速度センサ
JPH07294548A (ja) 半導体センサ
JP2002328136A (ja) 加速度センサ

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11868906

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11868906

Country of ref document: EP

Kind code of ref document: A1