CN105527042A - Pressure sensors and methods of making the same - Google Patents
Pressure sensors and methods of making the same Download PDFInfo
- Publication number
- CN105527042A CN105527042A CN201510666874.5A CN201510666874A CN105527042A CN 105527042 A CN105527042 A CN 105527042A CN 201510666874 A CN201510666874 A CN 201510666874A CN 105527042 A CN105527042 A CN 105527042A
- Authority
- CN
- China
- Prior art keywords
- silicon chip
- cavity
- pressure sensor
- diaphragm
- dielectric layer
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
Landscapes
- Measuring Fluid Pressure (AREA)
- Pressure Sensors (AREA)
Abstract
A pressure sensor assembly comprising: three stacked silicon wafers which form a support, a sensor and a cover wherein the sensor includes a cavity extending from the bottom of the sensor up towards the top of the sensor to form a cavity bottom and a diaphragm; a dielectric layer covering the bottom of the sensor and the cavity and wherein the support is coupled to the dielectric layer along the bottom of the sensor; a plurality of ports located on a top of the support within an area defined by the cavity, the plurality of ports extending through the support to its bottom and wherein the cover is coupled to the top of the sensor covering the diaphragm; and, a second cavity cut into a bottom of the cover wherein the second cavity is sized and positioned to surround the diaphragm.
Description
Technical field
The present invention relates to pressure transducer and manufacture method thereof.More specifically, the present invention relates to the pressure transducer be made up of silicon chip.
Background technology
The existing design of the high pressure dorsal part application of pressure transducer is inadequate for many application.General pressure transducer utilizes diaphragm as the pressure detecting element of this pressure transducer.This diaphragm is only exposed to malleation or negative pressure in side, produces a pressure differential across this diaphragm.This this diaphragm flexes of pressure official post, bending amount can cause the change of such as resistance or electric capacity, and this change can by circuit measuring.
A problem of existing design is, they are not restricted to the pressure flow of this diaphragm.Therefore, when this pressure transducer is exposed to acute variation, this diaphragm will experience pressure change very fast.This change of pressure fast may cause this diaphragm flexes to exceed its yield point, and this diaphragm of permanent damages, final this pressure transducer of damage.
Another problem of existing design is, silicon diaphragm is directly exposed to the medium needing to measure its pressure.The conductive fluid of noble potential is clashed into silicon face and big current will be caused to be flowed by sensor, and causes this sensor and/or the damage of the circuit of attachment on it.
The another problem of existing design is, when this diaphragm has reached its displacement limits, does not have detection means.Because such detection means likely weakens displacement limits state.
Summary of the invention
In view of mentioned above, according to an aspect of the present invention, object is to provide a kind of pressure sensor assembly.Preferably, these methods and device solve or at least improve above-mentioned one or more problem.For this reason, a kind of pressure sensor assembly is provided.In one embodiment, this pressure sensor assembly comprises: first silicon chip with top and bottom; Be formed at the cavity in described silicon chip, the top of described cavity from the bottom of the first silicon chip towards the first silicon chip upwards extends, and forms cavity bottom, makes to form diaphragm between described cavity bottom and described first silicon chip; Cover the bottom of described first silicon chip and the dielectric layer of described cavity; Conductive layer, such as metal (such as aluminium), or heavily doped polysilicon, it covers the top of the described diaphragm in described first silicon chip; Second silicon chip, its bottom along described first silicon chip is coupled to described dielectric layer, and covers described cavity; Be positioned at multiple ports in the region limited by described cavity at the top of described second silicon chip, the plurality of port extends through the bottom that described second silicon chip arrives described second silicon chip; 3rd silicon chip, it is coupled to the described top of described first silicon chip, makes described 3rd silicon chip cover described diaphragm; And second cavity, it is cut the bottom of described 3rd silicon chip, and the size of wherein said second cavity and position are configured such that described second cavity surrounds described diaphragm.
In a preferred embodiment, the degree of depth of the described second cavity moving displacement that is designed to mechanically to limit described diaphragm is to being less than 3 times of gamut line pressure shift.In preferably preferred embodiment, the degree of depth of described second cavity is less than or equal to 0.9 μm.
Again in other embodiments, described second cavity also can comprise the device having arrived at its displacement limits for detecting described diaphragm electronically.In this kind of embodiment, conductive layer can cover described cavity bottom or be desirably placed on described cavity bottom.Corresponding conductive layer can cover the described top of described diaphragm or be desirably placed on the described top of described diaphragm.Therefore, when described diaphragm arrives at its maximum displacement, the described conductive layers make contact on the bottom of the described conductive layer on the top of described diaphragm and described second cavity.These layers can by suitable design, size and shape, and make the contact completing circuit between these layers, therefore described in detection of electrons, the maximum displacement of diaphragm occurs.In certain embodiments, the described conductive layer in the bottom of described second cavity can with the contact electric connection on another region of described sensor module.In a preferred embodiment, described contact can be positioned on the top of described 3rd silicon chip.Described conductive layer can be made up of the metal of such as aluminium or heavily doped polysilicon.
In certain embodiments, the described cavity bottom forming described diaphragm is positioned at 80% of the distance at the top to described first silicon chip.In other embodiments, also other degree of depth can be used.
In a preferred embodiment, described dielectric layer makes the described circuit on described sensor and impacts the dielectric insulation of described diaphragm.In a preferred embodiment, described dielectric layer makes the described circuit on described sensor and described support member insulate.In a preferred embodiment, described dielectric layer is made up of the combination of silicon dioxide or silicon nitride or silicon dioxide and silicon nitride.In certain embodiments, do not use dielectric layer, described first silicon chip is directly coupled with described second silicon chip.
In certain embodiments, described pressure sensor assembly can be coupled to substrate further.In this kind of embodiment, described substrate can be coupled to the described bottom of described second silicon chip.Described substrate can comprise passage, and described passage extends to the bottom of described substrate from the top of described substrate.The opening of the passage at the top of described substrate can contain the opening of the multiple described port of the bottom of described second silicon chip.In certain embodiments, described substrate can be pedestal.
Other embodiment of pressure transducer is also described.In one embodiment, described pressure sensor assembly comprises: the first silicon chip, it has top surface and lower surface and mid-plane, mid-plane is limited at the centre position between described top surface and described lower surface, wherein said lower surface comprises cavity, described cavity upwards extends towards described top surface, forms cavity bottom through described mid-plane; Be formed at the diaphragm between described cavity bottom and described top surface; Second silicon chip, it is coupled to the described lower surface of described first silicon chip, and described second silicon chip covers described cavity with forming chamber; Multiple passage, it extends through described second silicon chip, and enters described room; 3rd silicon chip, it is coupled to the top surface of described first silicon chip, and described 3rd silicon chip comprises the second cavity, and size and the position of described second cavity are set up, to cover described diaphragm, and the mechanical stopping piece of described diaphragm is formed on the bottom of wherein said second cavity; And wherein, described first silicon chip and described second silicon chip are electrically insulated from each other by the dielectric layer be positioned at therebetween.
In a preferred embodiment, the described bottom of described second cavity can be coated with conductive layer, if the pressure being applied to described diaphragm makes the described conductive layers make contact on the bottom of the conductive layer at described diaphragm top and described second cavity, described conductive layer is located with closed circuit.
According to a further aspect in the invention, a kind of manufacture method of pressure sensor assembly is provided.In a preferred embodiment, described method comprises: by forming the cavity being extended upward into described first silicon chip by bottom, form sensor by described first silicon chip; Conductive layer is formed on the top of described first silicon chip; Dielectric layer is formed on the bottom and cavity of described first silicon chip; By forming multiple passage, form support member by the second silicon chip, wherein said multiple passage passes described second silicon chip to lower surface from top surface; The described bottom key of described first silicon chip is incorporated into the described top surface of described second silicon chip, make by described cavity forming chamber, described multiple passage leads to described room; By forming the second cavity, form lid by the 3rd silicon chip, wherein said second cavity extends upward into described 3rd silicon chip from bottom; The bottom key of described 3rd silicon chip is incorporated into the top of described first silicon chip, makes described second cavity surround described diaphragm.
In certain embodiments, the degree of depth of described second cavity is cut into 3 times that the moving displacement mechanically limiting described diaphragm is less than gamut line pressure shift.In certain methods, the described degree of depth of described second cavity is less than or equal to 0.9 μm, 1.1 μm, 1.3 μm or 1.5 μm.
In other embodiments, conductive layer also can be formed in the bottom of the described cavity of described 3rd silicon chip.Described conductive layer can with the contact electric connection be positioned on the top of described 3rd silicon chip.In addition, conductive layer also can be formed on the top of the described diaphragm of described first silicon chip.Described conductive layer can be positioned such that when described diaphragm reaches maximum displacement state, conductive layer electric connection on the bottom of the described cavity in the described conductive layer on the top of described diaphragm and described 3rd silicon chip, and completing circuit, it can be used to detect this maximum displacement state.
In some embodiments of described method, described dielectric layer is combined to form by silicon dioxide or silicon nitride or silicon dioxide and silicon nitride.Further, in some embodiments of described method, described pressure sensor assembly is coupled to the substrate of the bottom of described support member.
As hereafter described more fully, these embodiments of pressure transducer as herein described will be improved or will alleviate more previously mentioned problems.With reference to detailed description below and accompanying drawing (it only describes various embodiment by way of example), the feature of further aspect of the present invention, object, hope and the advantage of apparatus and method disclosed herein will be understood better.But be clearly understood that, accompanying drawing only for the object of example, and is not intended to as the restriction to advocated scope of invention.
Accompanying drawing explanation
Fig. 1 shows the isometric views of the embodiment being arranged on suprabasil pressure sensor assembly.
Fig. 2 shows the cross-sectional view of the pressure sensor assembly in Fig. 1.
Fig. 3 shows the partial enlarged view of the cross-sectional view of Fig. 2.
Fig. 4 shows multiple cross-sectional views of the silicon chip in the process of the embodiment forming sensor.
Fig. 5 shows multiple cross-sectional views of the silicon chip in the process of the embodiment forming support member.
Fig. 6 shows the cross-sectional view of the combination of the sensor in Fig. 4 and the support member in Fig. 5.
Fig. 6 A shows the xsect of Fig. 6, wherein on the top surface of pressure transducer, is added with conductive layer 57.
Fig. 7 shows multiple cross-sectional views of the silicon chip in the process of the embodiment forming lid.
Fig. 7 A shows multiple cross-sectional views of the silicon chip in the process of the embodiment forming lid, and wherein said cover is configured to the maximum displacement state electronically detecting described diaphragm.
It is combined with the cross-sectional view of the embodiment forming sensor module that Fig. 8 shows sensor in Fig. 4 and the support member in Fig. 5 and the lid in Fig. 7.
Fig. 9 shows the sensor module in Fig. 8, and the both sides of its middle cover 52 are cut.
Figure 10 shows the cross-sectional view of an embodiment of sensor module, and wherein sensor module is designed to the maximum displacement electronically detecting diaphragm.
Figure 11 shows the cross-sectional view of an embodiment of sensor module, and wherein dielectric layer is configured to different from the embodiment in Figure 10.
Embodiment
Employ in instructions at " top " and " bottom ", it provides orientation for helping to reader.These words also do not mean that the specific direction scope of embodiment be restricted to relative to gravity is directed, and only for providing relative to other elements of specific embodiment or the relative orientation of part and/direction.Such as, if establish " top " direction, then the opposite side at " bottom " top that is this embodiment, vice versa.Therefore, " upwards " is the direction from " bottom " to " top ", and " downwards " is the direction from " top " to " bottom ".
Fig. 1 shows the isometric views of the embodiment being arranged on suprabasil pressure sensor assembly.In the embodiment shown in fig. 1, whole assembly 100 comprises pressure sensor assembly 50 and substrate 10.Can use multiple diverse ways that pressure sensor assembly 50 is coupled to substrate 10.In a preferred embodiment, use eutectic solder technology, frit bonding techniques or bonding agent adhesive technology that pressure sensor assembly 50 is attached to substrate 10.The substrate 10 shown in Fig. 1 is exemplary, also can use the substrate 10 of other sizes or shape.
Pressure sensor assembly 50 comprises lid 52, sensor 54 and support member 56.In the embodiment comprising substrate 10, support member 56 is coupled to the top of substrate 10.Sensor 54 is coupled to the top of support member 56, and lid 52 is coupled to the top of sensor 54.
In a preferred embodiment, lid 52, sensor 54 and support member 56 are all made up of silicon (Si).In a more preferred embodiment, lid 52, sensor 54 and support member 56 are all made up of silicon chip.Therefore, sensor module can comprise three stacking silicon chips.In other embodiments, other materials can be used.The parts manufacturing sensor module 50 with silicon are favourable, and this is due to advanced manufacturing technology can be used to manufacture its parts, such as those technology used in MEMS (micro electro mechanical system) (MEMS).Usually, sensor module 50 can be MEMS device.
Can between 300 μm to 400 μm with the usual thickness of silicon chip in a preferred embodiment.In a preferred embodiment, silicon wafer thickness is 350 μm.In other embodiments, lid 52, the silicon chip that sensor 54 and support member 56 use can have other thickness.In various embodiments, each parts can use different thickness.In a preferred embodiment, the Miller's indices of the crystal orientation of silicon chip is 100.But, other crystal orientation can be used in other embodiments.
In a preferred embodiment, lid 52, sensor 54 and support member 56 are all made up of silicon chip, and are bonded to together with silicon bonding techniques.But, other bonding techniques can be used, particularly, if the material used is not silicon chip, likely use other bonding techniques.
The cross-sectional view of the embodiment of the pressure sensor assembly 50 of the substrate 10 comprised in Fig. 1 has been shown in Fig. 2.Pressure sensor assembly 50 is coupled to substrate 10 in the bottom of support member 56.In the embodiment shown in Figure 2, substrate comprises passage 12, and it extends to the bottom 13 of substrate 10 from the top 11 of substrate 10.In other embodiments, the passage of other types can also be used.Passage in substrate 10 can have uniform diameter, or can comprise two or more different diameter, or can be square or rectangle or polygon.Passage in substrate 10 can have different designs, but all should provide from the bottom of substrate 10 upwards until the connection of the bottom of support member 56.
As can be seen from Figure 2, support member 56 comprises multiple port 60, and sensor 56 comprises cavity 58.Support member 56 is attached on sensor 54, makes cavity 58 become room 58.Multiple port 60 extends through support member 56 at thickness direction.In a preferred embodiment, the opening of port is aligned to and makes them in room 58 for opening.Multiple port 60 is that the pressure upwards entered cavity 58 from the bottom of support member 56 provides path.
Fig. 3 shows the partial enlarged view of the xsect of Fig. 2.As can be seen from Figure 3, multiple port 60 extends through support member 56.Port 60 also can be called as passage or channel array.Use multiple less port 60 than using single comparatively large port to have advantage, because inhibit the pressure peak pouring in medium compared with the array of portlet 60, to protect sensor 54.Particularly, multiple port 60 inhibits the pressure peak of the diaphragm 59 of pressure transducer 54.In a preferred embodiment, multiple port 60 is built as, and compared with common single comparatively large port, has the diameter obviously reduced.In a preferred embodiment, port 60 is holed to support member 56 by using deep reactive ion etch (DRIE) instrument or passes through ultrasonic drilling or pass through machine drilling and formed.The shape of port 60 can be circular or square or rectangle or polygon.Flow velocity V in each passage
fit is the pressure P outside room 58
outwith the pressure P in room 58
inbetween pressure differential Δ p, the ratio of fluid density ρ, the diameter D of passage and the length L of passage, and the friction factor f of passage
dfunction.This relation is described by following formula
for this reason, select, make compared with single large port to the diameter of port 60 and length, the rate-of flow flowing into room reduces.In a preferred embodiment, convection cell, the maximum pressure differential that sensor will use, and D/L ratio is selected, and makes flow be reduced to 1/10th of flow when using single large port.In other embodiments, other reduction ratios can be designed for it.
In the embodiment shown in fig. 3, five ports from the bottom of support member 56 extend up to room 58.But, in other embodiments, the port of other quantity also can be used.In a preferred embodiment, 2 to 10 ports can be used.In a further advantageous embodiment, 5 to 10 ports can be used.Again in another embodiment, 5 to 50 ports can be used.Again in other more complicated embodiments, 50 or more ports can be used.。
Port is subject in the embodiment of the thickness limits of support member 56 wherein, and the length of port 60 is limited by the thickness of silicon chip.Therefore, only need to select diameter.In a preferred embodiment, the diameter of port is one of percentage of the maximum gauge of room 58 or less.Again in other embodiments, the diameter of port is 1/25 to 1/15 of the maximum gauge of room 58.Again in other embodiments, the diameter of port is 1/15 to 1/10 of the maximum gauge of room 58.Again in other embodiments, the diameter of port is 1/10 to 1/5 of the maximum gauge of room 58.
Multiple port 60 can be aligned to the top that access portal 15 is positioned at substrate 10, makes access portal 15 contain multiple port openings 60 on the bottom of support member 56.In other embodiments, some parts or more the part of port openings 60 can be positioned at outside access portal 15.
As can as seen from Figure 3, sensor 54 comprises cavity 58.This cavity upwards extends to form cavity bottom from the lower surface of described sensor 54, makes to form diaphragm between cavity bottom and the top of sensor 54.In a preferred embodiment, the bottom of described cavity extends towards the top surface of sensor 54, and extended distance is at least 80% of the distance arriving described top surface.In a more preferred embodiment, cavity bottom extends to the top surface of sensor 54, and extended distance is 85% to 95% of the distance arriving described top surface.The degree of depth of cavity 58 determines the thickness of diaphragm 59, thus determines the gamut pressure limit of pressure transducer 54.The thickness of sensor 54 is the distance between basal surface and top surface, and sensor 54 has the midplane in the centre position between top surface and basal surface.In a preferred embodiment, this cavity 58 upwards extends towards top surface, forms cavity bottom through mid-plane.
The minimum thickness (or depth capacity of cavity 58) of diaphragm 59 is determined by output target, and is subject to the restriction of manufacturing process.There is not the maximum gauge (or minimum-depth of cavity 58) of diaphragm 59.In a preferred embodiment, the thickness of diaphragm 59 is generally 10 microns to 95% of sensor wafer thickness.
Sensor 54 comprises the circuit of the top side being arranged on sensor 54.This circuit is used for the deflection of measuring diaphragm, and therefore measures pressure.This circuit can be formed by conductive layer 51.This conductive layer can be made up of any metal.Conductive layer 51 is used to form the circuit be embedded in the silicon of sensor.In a preferred embodiment, conductive layer 51 is conductive layers different from conductive layer 57 (as shown in Figure 6A).In certain embodiments, they can be made from a variety of materials and/or have different thickness.In other embodiments, the part that conductive layer 57 can be formed as circuit 51 maybe can be connected on it.
In order to make circuit electrical isolation to prevent potential short circuit, dielectric layer can be used between sensor 54 and support member 56.In a preferred embodiment, the bottom side of dielectric layer covering sensor 54 and cavity 58.Dielectric layer can be made up of any insulating material.In a preferred embodiment, dielectric layer is made up of silicon dioxide or silicon nitride.
The main source of short circuit is, when producing short circuit when the conductive fluid of noble potential enters described sensor module and clashes on a silicon surface.Contact between noble potential fluid and silicon may cause the big current of flows through sensor, causes sensor and/or the damage of circuit that is connected thereto.Therefore, circuit needs to carry out electrical isolation with the cavity of the fluid having inflow and passage.Its implementation can be as shown in the xsect of sensor module 50 in fig. 11, the wherein whole lower surface of dielectric layer 30 covering sensor.In a preferred embodiment, this comprises the surface between the surface of cavity 58 and sensor 54 and support member 56.In another embodiment, same electrical isolation can realize by applying a dielectric layer on all surfaces being exposed to the fluid of inflow, can find out in the cross-sectional view of sensor module 50 as shown in Figure 10.In a preferred embodiment, this can comprise the surface of whole room 58 and port 60.
Turn back in Fig. 3, lid 52 is coupled to the top of sensor 54.In a preferred embodiment, cover 52 and also comprise a cavity 62.Cavity 62 is in being coupled to sensor 54 side incision lid 52.Cavity 62 extends upward into lid and forms cavity bottom.Therefore, when lid 52 is assembled into sensor 54, cavity 62 forms gap above diaphragm 59.In a preferred embodiment, size and the position of covering the cavity 62 in 52 are configured such that cavity 62 surrounds the bottom of diaphragm 59.Also in a preferred embodiment, the degree of depth of cavity 62 is designed so that the motion of bottom limiting diaphragm 59 towards lid 52 of cavity 62.Therefore, the size of cavity and position are configured such that, when lid is coupled to sensor 54, mechanical stopping piece is served as in the bottom of cavity 62, to stop diaphragm 59, over-travel occur.
In a preferred embodiment, diaphragm 59 usually moves about 0.3-0.5 μm under gamut pressure.In order to effective stopping, the gap formed by cavity 62 needs to be greater than gamut displacement, if but be less than diaphragm when wherein not having retainer by the distance of surrender or explosion.Diaphragm surrender or fracture betide the gamut line pressure shift of 3 times to 5 times usually.Therefore, be the diaphragm of 0.3 μm for usual gamut line pressure shift, the degree of depth of cavity 62 can be greater than 0.3 micron but be less than 0.9 μm.The usual gamut line pressure shift of diaphragm is in another embodiment of 0.3 μm wherein, and the degree of depth of cavity 62 can be greater than 0.3 μm but be less than 1.5 μm.In other embodiments, according to the design of diaphragm, other cavity depth can be used.
Present by description one group of accompanying drawing, so that the process of the embodiment building pressure sensor assembly 50 to be described.In the present embodiment, pressure sensor assembly 50 is formed by 3 that are bonded together independent silicon wafers.Pressure sensor assembly 50 will comprise multiple port 60, and have lid 52 and the dielectric layer of mechanical stopping piece, this dielectric layer makes electrical isolation between sensor 54 and support member 56.In other embodiments, other combination or configuration can also be built.
Fig. 4 shows multiple cross-sectional views of the silicon chip in the process of the embodiment forming sensor 54.In step 1, the method preferably from resistance be 10 Ω cm+/-20%, thickness is the N-shaped <100>Si wafer of 350 μm.In step 2, with the addition of oxide layer along with SiN deposition.In a preferred embodiment, photoresist spin coating is carried out.Cavity mask passes through SiN etching and the oxide etching of suitably placing and set size, and photoresist stripping is subsequently formed.In step 3, therefore KOH etching for generation of the cavity 58 of sensor 54, and produces diaphragm 59.KOH etching preferably etches into the degree of depth of wafer thickness 90%.Also corners (cornerrounding) is preferably carried out in this step.In step 4, SiN and oxide skin(coating) are stripped.
Fig. 5 shows multiple cross-sectional views of the silicon chip in the process of the embodiment forming support member 56.In step 1, the method preferably starts from the <100>Si sheet that thickness is 350 μm.In step 2, the mask of multiple port 60 is formed by following steps: apply oxide layer, carry out photoresist spin coating, then expose port mask, carry out oxide etching.In step 3, multiple port 60, by first carrying out deep reactive ion etch (DRIE), carries out photoresist stripping subsequently and is formed.Finally, in step 4, oxide skin(coating) is stripped.
Fig. 6 shows the cross-sectional view that sensor in Fig. 4 54 and the support member 56 in Fig. 5 carry out combining.In a preferred embodiment, two silicon chips are carried out silicon-to-silicon bonding, then assembly is oxidized, to prepare the circuit of the diaphragm displacement of formation one on the top surface of detecting sensor 54.As known to those skilled in the art, carry out series of steps, to form described circuit.This series of steps comprises plated metal and pattern metal, such as, and aluminium.The metal of this patterning not only can form circuit, and it also can be used as a part for electrical contact, and described electrical contact forms the maximum displacement detector switch (maximumdisplacementdetectionswitch) of the top side of diaphragm 59.
Fig. 6 A shows the xsect of Fig. 6, and wherein conductive layer 57 is added on the top surface of pressure transducer 54.As can be found out in fig. 6, a part for conductive layer can be formed on diaphragm 59, to provide electrical contact for maximum displacement detector switch.
Fig. 7 shows multiple cross-sectional views of the silicon chip of the embodiment forming lid 52.In step 1, the method preferably starts from resistance to be 0.1 Ω cm or following, thickness the be <100>Si wafer of 350 μm.In step 2, first carry out photoresist spin coating, form groove mask subsequently.Cavity 62 is formed by DRIE.Then, photoresist stripping is carried out.
Fig. 7 A shows multiple xsects of the silicon chip in the process of the embodiment forming lid, and wherein said cover is configured to the maximum displacement state electronically detecting described diaphragm.In a preferred embodiment, this lid 52 can, not only as mechanical arresting device, also can be configured to serve as electric detector switch.In such embodiments, cavity 62 is coating is stamped conductive layer 63, and conductive layer 63 is electrically connected to described lid 52.Conductive layer can be made up of any metal.Therefore, when diaphragm 59 arrives the bottom of cavity 62, the conductive layer 57 on diaphragm 59 contacts with the conductive layer 63 in the cavity of described lid 52.Preferably, this contact forms a closed circuit, and this closed circuit can detect with a testing circuit, and this testing circuit can make high pressure source be prohibited, or by opening another valve to ease off the pressure.
As seen in fig. 7, in step 3, conductive layer, such as aluminium, be deposited over the bottom side of lid 52.Then carry out photoresist spin coating, carry out mask and etching step subsequently.In step 4, conductive layer, such as aluminium, be deposited on the top side of lid 52, and the conductive layer on the top side of lid 52 with the electrical contact accomplishing conductive layer 63, then, can carry out photoresist spin coating, carry out mask and etching step subsequently.
Fig. 8 illustrates sensor 54 and support member 56 and covers 52 combined with the xsect forming sensor module 50.In a preferred embodiment, lid 52 is bonded to the top of sensor 54 to silicon by silicon.Then, be bonded to the stacking of three silicon chips together and can carry out titanium/platinum/gold deposition on the bottom side of wafer stacking.Fig. 9 shows the sensor module in Fig. 8, and the both sides of its middle cover 52 are cut.
Figure 10 shows the cross-sectional view of an embodiment of sensor module, and wherein sensor module is designed to the maximum displacement electronically detecting diaphragm.As found out in Fig. 10, conductive layer 63 is deposited on the bottom of the cavity 62 in lid 52.In addition, conductive layer 57 is deposited on the top of diaphragm 59.When diaphragm flexes is to its maximum displacement, two conductive layers 57 contact with 63 and complete a circuit.Completing of circuit is detected, and system knows that diaphragm has reached its maximum displacement.In a preferred embodiment, the detection of maximum displacement may cause action, to alleviate or to remove overvoltage condition.
As what also can find out in Fig. 10, dielectric layer covers the inside of cavity 58 and the inside of port/channel 60.Therefore, dielectric layer 30 makes cavity 58 and port/channel 60 and sensor 54 electrical isolation.As found out in the present embodiment, sensor 54 and support member 56 are directly coupled together.
Figure 11 illustrates the cross-sectional view of an embodiment of sensor module, and wherein said dielectric layer is configured to different from the embodiment of Figure 10.As found out in fig. 11, be not cover all cavitys 58 and port 60, but the whole lower surface of dielectric layer 30 covering sensor 54.Although the dielectric layer in the embodiment of Figure 11 has different configurations, it has identical function, that is, make electrical isolation between sensor 54 and support member 56.Can find out in fig. 11, in such embodiments, sensor 54 is not directly coupled to support member 56, because dielectric layer 30 is placed between which.
Although be described embodiments of the invention with reference to preferred disposition and specific examples; but those skilled in the art can easily understand; many amendments and adjustment can be carried out to pressure transducer and manufacture method thereof, and not depart from the spirit and scope as hereinafter claimed embodiment.Therefore, it should be clearly understood that this instructions is described by means of only the mode of example, instead of as the restriction of the scope to such as hereafter claimed embodiment.
Claims (39)
1. a pressure sensor assembly, comprising:
First silicon chip, described first silicon chip has top and bottom;
Be formed in the cavity in described first silicon chip, the top of described cavity from the bottom of described first silicon chip towards described first silicon chip upwards extends, and forms cavity bottom, makes to form diaphragm between described cavity bottom and the top of described first silicon chip;
Circuit, it is formed by the conductive layer at the described top being arranged on described first silicon chip;
Second silicon chip, described second silicon chip along the described bottom coupling of described first silicon chip, and covers described cavity, with forming chamber;
Dielectric layer, described dielectric layer makes electrical isolation between the inside of described room and described first silicon chip;
Multiple port, described multiple port is positioned at the region limited by described cavity at the top of described second silicon chip, and described multiple port extends through the bottom that described second silicon chip arrives described second silicon chip;
3rd silicon chip, described 3rd silicon chip is coupled to the described top of described first silicon chip, makes described 3rd silicon chip cover described diaphragm; And
Second cavity, the bottom of described 3rd silicon chip of described second cavity incision, the size of wherein said second cavity and position are configured such that described second cavity surrounds described diaphragm.
2. pressure sensor assembly according to claim 1, the moving displacement that the degree of depth of wherein said second cavity is designed to mechanically to limit described diaphragm is to being less than 3 times of gamut line pressure shift.
3. pressure sensor assembly according to claim 1, the second electrical contact of the electrical contact also comprising the top being positioned at described diaphragm and the bottom that is positioned at described second cavity.
4. pressure sensor assembly according to claim 3, wherein when described diaphragm moves to the full degree of depth in described second cavity, described electrical contact will contact with described second electrical contact, and form closed circuit.
5. pressure sensor assembly according to claim 1, the degree of depth of wherein said second cavity is less than or equal to 0.9 μm.
6. pressure sensor assembly according to claim 1, the bottom of wherein said cavity is positioned at least 80% of the distance at the top to described first silicon chip.
7. pressure sensor assembly according to claim 1, wherein said dielectric layer is made up of silicon dioxide or silicon nitride.
8. pressure sensor assembly according to claim 1, also comprise substrate, described substrate is coupled to the bottom of described second silicon chip, described substrate comprises passage, described passage extends to the bottom of described substrate from the top of described substrate, and the opening of the multiple described port of the bottom of described second silicon chip wherein, is encompassed at the opening of the passage at the top of described substrate.
9. pressure sensor assembly according to claim 1, described first silicon chip and described second silicon chip separate by wherein said dielectric layer.
10. pressure sensor assembly according to claim 1, wherein said dielectric layer covers the inside of described room.
11. 1 kinds of pressure sensor assemblies, comprising:
First silicon chip, described first silicon chip has top surface and lower surface and mid-plane, described mid-plane is limited at the centre position between described top surface and described lower surface, wherein said lower surface comprises cavity, described cavity upwards extends towards described top surface, forms cavity bottom through described mid-plane;
Diaphragm, described diaphragm is formed between described cavity bottom and described top surface;
Second silicon chip, described second silicon chip is coupled to the described lower surface of described first silicon chip, and described second silicon chip covers described cavity with forming chamber;
Multiple passage, described multiple passage extends through described second silicon chip, and enters described room;
3rd silicon chip, described 3rd silicon chip is coupled to the described top surface of described first silicon chip, described 3rd silicon chip comprises the second cavity, and the size of described second cavity and position are configured to cover described diaphragm, and the mechanical stopping piece of described diaphragm is formed on the bottom of wherein said second cavity;
And wherein, described room is by electrical isolation between dielectric layer and described first silicon chip.
12. pressure sensor assemblies according to claim 11, the degree of depth of wherein said second cavity is less than or equal to 0.9 μm.
13. pressure sensor assemblies according to claim 11, wherein said cavity bottom extends towards the described top surface of described first silicon chip, and extended distance is at least 80% of the distance arriving described top surface.
14. pressure sensor assemblies according to claim 11, wherein said dielectric layer is made up of silicon dioxide or silicon nitride.
15. pressure sensor assemblies according to claim 11, the second electrical contact of the electrical contact also comprising the top being positioned at described diaphragm and the bottom that is positioned at described second cavity.
16. pressure sensor assemblies according to claim 11, also comprise substrate, described substrate is coupled to the bottom side of described second silicon chip, described substrate comprises substrate channel, described substrate channel extends to the bottom of described substrate from the top of described substrate, and the access portal of the multiple described passage being positioned at described second silicon chip wherein, is covered at the open-topped substrate channel of described substrate.
17. 1 kinds of sensor modules, comprising:
The chaffy sensor of tool, described sensor has top and bottom;
Lid, described cover is coupled to the top of described sensor, and forms gap on described diaphragm, and the gamut that described gap is designed to limit described diaphragm moves;
Support member, described support member is coupled to the bottom of described sensor, wherein said support member and described sensor form the room adjacent with described diaphragm, and wherein said support member comprises multiple passage, multiple passages of described support member are upward through described support member from the bottom of described support member and enter described room; With,
Dielectric layer, described dielectric layer makes described room and described multiple passage all insulate with described sensor electrical.
18. pressure sensor assemblies according to claim 17, wherein said gap is less than or equal to 0.9 μm.
19. pressure sensor assemblies according to claim 17, also comprise the second electrical contact of the electrical contact being positioned at described diaphragm top and the bottom being positioned at the described lid on described gap.
20. pressure sensor assemblies according to claim 17, described sensor and described support member separate by wherein said dielectric layer.
21. 1 kinds of methods manufacturing pressure sensor assembly, comprising:
By forming the cavity being extended upward into the first silicon chip by bottom, form sensor by described first silicon chip;
Conductive layer is formed at the top of described first silicon chip;
By forming multiple passage, form support member by the second silicon chip, wherein said multiple passage passes described second silicon chip to lower surface from top surface;
The bottom key of described first silicon chip is incorporated into the top surface of described second silicon chip, make by described cavity forming chamber, described multiple passage leads to described room;
Form dielectric layer, described dielectric layer makes electrical isolation between described room and described sensor;
By forming the second cavity, form lid by the 3rd silicon chip, wherein said second cavity extends upward into described 3rd silicon chip from bottom; With
The bottom key of described 3rd silicon chip is incorporated into the top of described first silicon chip, makes described second cavity surround described diaphragm.
The method of 22. manufacture pressure sensor assemblies according to claim 21, the degree of depth of wherein said second cavity is cut into the moving displacement that mechanically limits described diaphragm to being less than 3 times of gamut line pressure shift.
The method of 23. manufacture pressure sensor assemblies according to claim 21, the degree of depth of wherein said second cavity is less than or equal to 0.9 μm.
The method of 24. manufacture pressure sensor assemblies according to claim 21, wherein said dielectric layer is made up of silicon dioxide or silicon nitride.
The method of 25. manufacture pressure sensor assemblies according to claim 21, described sensor and described support member separate by wherein said dielectric layer.
The method of 26. manufacture pressure sensor assemblies according to claim 21, wherein said dielectric layer covers the surface of described room.
The method of 27. manufacture pressure sensor assemblies according to claim 21, also comprise described lower surface substrate being attached to described support member, wherein said substrate comprises passage, described passage extends to the bottom of described substrate from the top of described substrate, and wherein contains described multiple passage of the described lower surface of described support member in the access portal at the top of described substrate.
The method of 28. manufacture pressure sensor assemblies according to claim 21, conductive layer is formed on the bottom being also included in the described cavity of described 3rd silicon chip.
The method of 29. manufacture pressure sensor assemblies according to claim 21, electrical contact is formed on the top being also included in described 3rd silicon chip, and described electrical contact is connected to the described conductive layer on the bottom of the described cavity of described 3rd silicon chip.
The method of 30. manufacture pressure sensor assemblies according to claim 21, wherein, when described diaphragm moves to the full degree of depth of described second cavity, the described conductive layers make contact of the conductive layer of the top side of described diaphragm and the bottom of described second cavity, and form closed circuit.
31. 1 kinds of methods manufacturing pressure sensor assembly, comprising:
Form sensor by the first silicon chip, wherein said sensor comprises diaphragm;
Circuit is formed on the top of described sensor;
Support member is formed by the second silicon chip;
The bottom key of described first silicon chip is incorporated into the top surface of described second silicon chip, makes to form the room encapsulated by described first silicon chip and described second silicon chip;
Form multiple passage, described multiple passage arrives the lower surface of described second silicon chip through described second silicon chip from described room;
Form dielectric layer, described dielectric layer makes electrical isolation between described room and described sensor;
Lid is formed by the 3rd silicon chip; With
The bottom key of described 3rd silicon chip is incorporated into the top of described first silicon chip, the gap on described diaphragm is between described sensor and described lid.
The method of 32. manufacture pressure sensor assemblies according to claim 31, wherein said gap is less than 3 times of the gamut line pressure shift of described diaphragm.
The method of 33. manufacture pressure sensor assemblies according to claim 31, wherein said gap is less than or equal to 0.9 μm.
The method of 34. manufacture pressure sensor assemblies according to claim 31, wherein said dielectric layer is made up of silicon dioxide or silicon nitride.
The method of 35. manufacture pressure sensor assemblies according to claim 31, wherein said dielectric layer makes described sensor and described support member separate.
The method of 36. manufacture pressure sensor assemblies according to claim 31, wherein said dielectric layer covers the surface of described room.
The method of 37. manufacture pressure sensor assemblies according to claim 31, formation second conductive layer on the surface being also included in the described gap relative with described conductive layer on described diaphragm.
38. according to the method for manufacture pressure sensor assembly according to claim 37, and the top being also included in described 3rd silicon chip forms electrical contact, with described second conductive layer electric connection.
39. according to the method for manufacture pressure sensor assembly according to claim 37, wherein when described diaphragm moves to the full degree of depth of described room, and described conductive layer and described second conductive layers make contact, and form closed circuit.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US14/515,470 US9506827B2 (en) | 2014-10-15 | 2014-10-15 | Pressure sensors and methods of making the same |
| US14/515480 | 2014-10-15 | ||
| US14/515,480 US9212054B1 (en) | 2014-10-15 | 2014-10-15 | Pressure sensors and methods of making the same |
| US14/515470 | 2014-10-15 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105527042A true CN105527042A (en) | 2016-04-27 |
| CN105527042B CN105527042B (en) | 2020-06-05 |
Family
ID=55769410
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510666874.5A Active CN105527042B (en) | 2014-10-15 | 2015-10-15 | Pressure sensor and method for manufacturing the same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105527042B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101248340A (en) * | 2005-08-24 | 2008-08-20 | 通用电气公司 | Pressure sensors and methods of making the same |
| CN101344447A (en) * | 2007-07-13 | 2009-01-14 | 清华大学 | Micro-electromechanical pressure transducer |
| CN102105769A (en) * | 2008-05-23 | 2011-06-22 | 霍尼韦尔国际公司 | Media isolated differential pressure sensor with cap |
| US20130200439A1 (en) * | 2010-01-11 | 2013-08-08 | Elmos Semiconductor Ag | Micro-electromechanical semiconductor component |
| CN103562697A (en) * | 2011-05-30 | 2014-02-05 | 埃普科斯股份有限公司 | Pressure sensor and method for producing a pressure sensor |
-
2015
- 2015-10-15 CN CN201510666874.5A patent/CN105527042B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101248340A (en) * | 2005-08-24 | 2008-08-20 | 通用电气公司 | Pressure sensors and methods of making the same |
| CN101344447A (en) * | 2007-07-13 | 2009-01-14 | 清华大学 | Micro-electromechanical pressure transducer |
| CN102105769A (en) * | 2008-05-23 | 2011-06-22 | 霍尼韦尔国际公司 | Media isolated differential pressure sensor with cap |
| US20130200439A1 (en) * | 2010-01-11 | 2013-08-08 | Elmos Semiconductor Ag | Micro-electromechanical semiconductor component |
| CN103562697A (en) * | 2011-05-30 | 2014-02-05 | 埃普科斯股份有限公司 | Pressure sensor and method for producing a pressure sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105527042B (en) | 2020-06-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101332701B1 (en) | Microelectromechanical pressure sensor including reference capacitor | |
| US9212054B1 (en) | Pressure sensors and methods of making the same | |
| US9518877B2 (en) | Micromechanical component for a capacitive sensor device, and manufacturing method for a micromechanical component for a capacitive sensor device | |
| CN103969296B (en) | Sensor device and its manufacturing method based on film | |
| JP5649474B2 (en) | Capacitance type pressure sensor and method of manufacturing capacitance type pressure sensor | |
| US9670059B2 (en) | Sensor structure for sensing pressure waves and ambient pressure | |
| EP2871456A1 (en) | Pressure sensor | |
| KR20080015862A (en) | Silicon microphone | |
| US8252695B2 (en) | Method for manufacturing a micro-electromechanical structure | |
| EP2082422A2 (en) | Formation of through-wafer electrical interconnections and other structures using an etch stop layer | |
| JP2005345294A (en) | Acceleration sensor and its manufacturing method | |
| KR102588550B1 (en) | Micromechanical pressure sensor device and corresponding manufacturing method | |
| US7989263B2 (en) | Method for manufacturing a micromechanical chip and a component having a chip of this type | |
| WO2015042701A1 (en) | Mems device including an electrode guard ring and method of manufacturing the same | |
| CN111170265A (en) | MEMS device and method of manufacturing the same | |
| CN103130174B (en) | MEMS and forming method thereof | |
| CN117069053A (en) | Semiconductor device and method for manufacturing the same | |
| EP3127158B1 (en) | Membrane-based sensor and method for robust manufacture of a membrane-based sensor | |
| TWI652728B (en) | Epi-poly etch stop for out of plane spacer defined electrode | |
| EP3614372B1 (en) | Method for manufacturing an air pulse generating element | |
| EP3290389A1 (en) | Method for reducing cracks in a step-shaped cavity | |
| US20100064808A1 (en) | Acceleration sensor and method of manufacturing acceleration sensor | |
| US9506827B2 (en) | Pressure sensors and methods of making the same | |
| CN105527042A (en) | Pressure sensors and methods of making the same | |
| EP3328093A1 (en) | Mems microphone having reduced leakage current and method of manufacturing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |