Compact sensing apparatus having an orthogonal sensor and methods for forming same

A sensing apparatus having a sensor formed in a monolithic semiconductor substrate and oriented orthogonally to a signal conditioner is provided. The sensor generates a sensing signal in response to a predetermined physical stimulus. A signal conditioner electrically connected and responsive to the sensor conditions the sensing signal. The signal conditioner, moreover, is preferably formed in the same semiconductor substrate and, more preferably is oriented at a right angle relative so as to be orthogonal to the sensor to thereby enhance the compactness of the sensing apparatus.

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
RELATED APPLICATIONS

[0001] This application claims priority to Provisional Application Ser. No. 60/288,312, filed May 2, 2001, and incorporates by reference the disclosures of Provisional Application Ser. No. 60/288,282 filed May 2, 2001, Provisional Application Ser. No. 60/288,313 filed May 2, 2001, Provisional Application Ser. No. 60/287,856 filed May 1, 2001, Provisional Application Ser. No. 60/287,763 filed May 1, 2001, Provisional Application Ser. No. 60/288,281 filed May 2, 2001, and Provisional Application Ser. No. 60/288,279 filed May 2, 2001.

FIELD OF THE INVENTION

[0002] The present invention relates to the field of sensing apparatuses and, more particularly, to the field of sensing apparatuses having a sensing element formed in a monolithic semiconductor substrate.

BACKGROUND OF THE INVENTION

[0003] Sensing apparatuses are widely used in various types of mechanical and electrical systems for detecting and measuring myriad physical and chemical phenomena. The various uses for such devices include sensing the presence and intensity of electrical and magnetic fields, detecting mechanical forces, measuring the temperature or flow of a liquid or gas, and registering the acceleration of a solid body.

[0004] Over the years various types of sensing devices have been developed to accomplish these disparate tasks. Some of the sensing apparatuses developed rely on a sensing element (e.g. a transducer) having a specific preferred orientation in relation to an electrical or magnetic field or to a mechanical force to be sensed. Typical examples of electrical or magnetic field sensing elements are position and proximity sensors such as a Hall-effect cell, magnetoresistor, capacitive sensing element, and inductive sensing elements. An example of a mechanical force sensing element is a stress gauge that measures mechanical stress or weight of an object. Another example of a mechanical force sensing element is the accelerometer, which measures the acceleration of an object.

[0005] These sensing devices, then, typically have a preferred orientation for the sensing element relative to the electrical or magnetic field or to the physical force being sensed. The device thus must be oriented so that the sensing element has the preferred orientation if the sensor's sensitivity is to be magnetized. There also may be extraneous electrical or magnetic fields or mechanical forces associated with use of the system with which the sensing device must accommodate, preferably by orienting the sensor relative to these extraneous fields or forces in a specific direction so as to reduce the sensor's sensitivity to the extraneous fields or forces. Such orientation can reduce sensing errors or noise caused by the presence of other fields or forces within the vicinity of the sensing device or the movement of other objects.

[0006] Sensing apparatuses typically also rely on signal conditioning circuitry to amplify or otherwise condition the sensing signal that typically has too low a magnitude to overcome extraneous noise effects. The signal conditioning circuitry is also employed to condition a sensing signal that contains a large offset or other error signal that can overdrive sensitive monitoring equipment. Indeed, the signal conditioning circuitry can condition a sensing signal not otherwise conducive to transmission over an extended distance to a remotely located electrical device such a sensor monitoring circuit.

[0007] In the manufacture of a sensing apparatus, the sensing element, generally defining a sensor, and the corresponding signal conditioning circuitry defining a signal conditioner are both formed on a common surface of a semiconductor wafer. Conventional techniques for manufacturing a sensing apparatus generally leave the sensor and the signal conditioner on a common, single-plane surface. Conductive traces are then formed directly on the common surface between the sensor and signal conditioner to electrically connect each with the other. Therefore, for a sensing apparatus having a signal conditioner formed in a common plane with the sensor, the combined extent of the surface area required for both the sensor and the signal conditioner will generally dictate the overall size of the sensing apparatus.

[0008] Having the sensor and the signal conditioner formed on a common plane inevitably results in the sensing apparatus having a relatively large surface area relative to the depth of the device. Moreover, because the sensor will of necessity be oriented with respect to the field or force to be sensed, one will be constrained in attempts at orienting the sensing apparatus in a system so as to accommodate the surface area of the sensing apparatus. The electrical and mechanical systems in which sensing apparatuses are employed, however, have become increasingly smaller over the years. Yet the ability to position the sensing apparatus in an electrical or mechanical system of limited size, though, is accordingly severely constrained depending on the preferred orientation of the sensor and the orientation of the signal conditioner relative to the sensor. Thus, there is a need for a sensing apparatus having a smaller surface area than conventional ones having the sensor and signal conditioner positioned in the same plane.

[0009] The amount of area occupied by the sensor is typically much smaller than the area occupied by the signal conditioner. Moreover, in contrast to the sensor, the signal conditioner does not require a specific orientation relative to the electrical or magnetic field or the mechanical force that is to be sensed by the sensing apparatus. One way of achieving a reduced cross section, then, is to physically separate the sensor and signal conditioner, and orient the separated components in separate planes while maintaining the necessary electrical connection between them. Because the electrical and mechanical systems in which the sensing apparatuses will be employed are likely to be subjected to significant stress forces, however, it is necessary to maintain the structural integrity of the sensing apparatus, especially the necessary electrical connection between the sensor and the signal conditioner. Therefore, there also is a need for a sensing apparatus that achieves both a reduction in overall size while maintaining its structural integrity.

SUMMARY OF THE INVENTION

[0010] With the foregoing in mind, the present invention advantageously provides a sensing apparatus reduced in size by orienting the sensor and signal conditioner in separate planes while maintaining the overall structural integrity of the device. In addition, the method aspects of the present invention advantageously provide means for forming a compact sensing apparatus having structural integrity.

[0011] More specifically, the present invention provides a compact sensing apparatus having a sensor formed in a surface of a monolithic semiconductor substrate and a signal conditioning circuitry defining a signal conditioner formed in the same semiconductor substrate. The sensor and signal conditioner are oriented relative to each other to advantageously reduce the overall size of the sensing apparatus. The sensor generates a sensing signal in response to a predetermined physical stimulus. The signal conditioner senses the sensing signal generated by the sensor in response to the predetermined physical stimulus. The physical stimulus can be an electric field, a magnetic field, or a mechanical force.

[0012] A significant advantage of the present invention is the orientation of the sensor relative to the signal conditioner. Specifically, the sensor is oriented orthogonally to the signal conditioner and positioned on a surface substantially smaller than the surface on which the signal conditioner is positioned. Orthogonal orientation reduces the lengthwise extent of the sensing apparatus, making the device much more compact than conventional devices having same-plane sensor and signal conditioning circuitry. Specifically, because the depth (or height) and lateral extent of the sensing apparatus will be a function of the surface area of the surface on which the sensor is formed, orienting the sensor orthogonally relative to the surface on which the signal conditioner is formed accordingly reduces the height and lateral extend of the compact sensing apparatus.

[0013] Moreover, because the sensor and signal conditioner are formed on separate planes of a monolithic semiconductor substrate rather than positioned separately, the structural integrity of the sensing apparatus is accordingly enhanced. In addition, the sensor and the signal conditioner are electrically connected via a stable electrical connection that can resist breakage by being formed on the monolithic semiconductor substrate. The electrical connection more specifically can include at least one integrated conductor formed in the monolithic semiconductor substrate by, for example, heavily doping a region of the substrate. The at least one integrated conductors preferably are formed in and extend over an edge portion of the monolithic semiconductor substrate. The edge more specifically is the edge shared by the surface on which the sensor is formed and the separate surface on which the signal conditioner is formed.

[0014] A conductive path between the sensor and the signal conditioner can be provided by including at least one pair of metal conductors also formed on the monolithic semiconductor substrate. One of the at least one pair of metal conductors connects to the at least one integrated conductor and extends along the surface on which the sensor is formed to connect to the sensor. The other of the at least one pair of metal conductors preferably connects to the same at least one integrated conductor and extends along the surface in which the signal conditioner is formed to connect to the signal conditioner. The respective conductors extending from the sensor and the signal conditioner, each on separate planes of the same semiconductor substrate, are electrically connected at the edge-positioned integrated conductor so as to complete a stable, reliable conductive path between the sensor and the signal conditioner.

[0015] The sensor positioned orthogonally on the monolithic substrate can sense electrical or magnetic fields, as well as mechanical forces oriented perpendicularly or horizontally relative to the sensor, depending on the nature of the sensor. More specifically an orthogonal sensor will sense electrical or magnetic fields, or mechanical forces, oriented perpendicularly to the planar surface of the sensor. Alternatively, a transverse sensor can sense electrical or magnetic fields, or mechanical forces that are oriented parallel to the planar surface of the sensor.

[0016] A second conductive path can also be provided, one which links the sensing apparatus to a remote electrical device such as a sensing monitor. The second conductive path, specifically, can include an electrical conductor that electrically connects to the signal conditioner and extends from the signal conditioner to connect to the preselected electrical device, the device being positioned apart from the sensing apparatus. Thus, the conductive path thereby forms a conductive path between the compact sensing apparatus and the remotely positioned preselected electrical device. The preselected electrical device preferably will be a sensing monitor. The compact sensing apparatus also can include a mounting base to which the monolithic substrate is attached to thereby provide a separate or additional support structure underlying the substrate-mounted sensor and substrate-mounted signal conditioner.

[0017] The sensing apparatus, moveover, can further include a housing or other type of encapsulation extending over all or a portion of the sensing apparatus to thereby encapsulate at least a portion of the signal conditioner SO as to provide a protective cover the sensing apparatus. The electrical conductor providing the conductive path between the signal conditioner and a remotely positioned electrical device, then, extends through the encapsulation to thereby electrically connect the sensing apparatus with the sensing monitor or other preselected electrical device.

[0018] In yet an additional embodiment, the sensing apparatus includes an encapsulation extending over the sensor as well as the signal conditioner. Specifically, with respect to a sensor comprising a magnetoresistor or Hall element cell, the encapsulation preferably is a nonmagnetic material that partially encapsulates the sensor and the signal conditioner that are both formed on the monolithic semiconductor substrate. Moreover, the sensor can be a magnetoresistor or Hall element cell. In the case of magnetic sensor, the encapsulation preferably further comprises a magnetic encapsulation that partially encapsulates the sensor and the signal conditioner and is positioned behind the planar surface of the sensor. The magnetic material of the magnetic encapsulation, moreover, is preferably charged in a direction parallel to an imaginary straight line extending between the sensor and the magnetic encapsulation, the line being generally perpendicular to both the planar surface of the sensor and the edge of the magnetic encapsulation that is closest to or abuttingly in contact with the monolithic semiconductor substrate. In each of the respective embodiments of the present invention, the sensors can be any of a variety of sensing element types that generate a sensing signal in response to one of a host of physical stimuli. The sensor, for example, can be a magnetoresistor or a Hall-effect cell for detecting magnetic fields, as already noted. The sensor alternatively can be capacitive transducer for detecting electrical fields. Types of sensors also include ones for detecting mechanical forces such as pressure sensors, flow sensors, and accelerometers. These and a host of other types of sensors can be accommodated with the present invention as will be readily apparent to those of skilled in the relevant art.

[0019] The present invention, moreover, encompasses various method aspects as well. The present invention provides a method for forming a compact sensing apparatus that includes positioning a signal conditioner on a monolithic semiconductor substrate. The monolithic semiconductor substrate, for example, can be cut from a wafer of semiconductor material on which a signal conditioner has been formed. Preferably, a plurality of signal conditioners will be formed on one wafer surface in order to efficiently form multiple sensing apparatuses. After the plurality of signal conditioners is formed on the wafer surface, the wafer surface is cut into multiple monolithic semiconductor substrates, each of which has a signal conditioner formed thereon. If the signal conditioner has been formed on the surface of the wafer and the wafer cut into an individual monolithic semiconductor substrate, the substrate (or each of a plurality of substrates) is then rotated appropriately so that a sensor can be formed on a distinct plane of the monolithic semiconductor substrate. The sensor and the signal conditioner will be electrically connected and oriented orthogonally relative to each other.

[0020] The method aspects of the invention further include forming at least one integrated conductor on the monolithic semiconductor substrate, preferably by doping the monolithic semiconductor substrate with a suitable material for making the semiconductor conductive so as to thereby form the integrated conductor having the desired conductive properties for completing a conductive path between the sensor and the signal conditioner. Using the at least one integrated conductor as an electrical juncture, the conductive path between the sensor and the signal conditioner can be completed by electrically connecting the sensor to at least one integrated conductors and electrically connecting the signal conditioner to the same integrated conductor to thereby form the conductive path.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Some of the features, advantages, and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings in which:

[0022] FIG. 1 is a perspective view of a sensing apparatus according to the present invention;

[0023] FIG. 2 is a perspective view of a mounted sensing apparatus according to the present invention;

[0024] FIG. 3 is a side elevational view of a sensing apparatus according to the present invention;

[0025] FIG. 4 is a side elevational view of a sensing apparatus according to the present invention;

[0026] FIG. 5 is perspective view a sensing apparatus according to the present invention;

[0027] FIG. 6 is a perspective view of a sensing apparatus according to the present invention;

[0028] FIG. 6A is a cross sectional view of a sensing apparatus according to the present invention; and

[0029] FIG. 7 is a perspective view of a sensing apparatus according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The present invention will now be described more fully hereinafter with reference to the accompanying drawings which illustrate preferred embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout, the prime notation, if used, indicates similar elements in alternative embodiments.

[0031] FIG. 1 illustrates a compact sensing apparatus 20 according to a first embodiment of the present invention. The compact sensing apparatus 20 includes a monolithic substrate 22 having a sensor surface 24 and a signal conditioner surface 26, a sensor 34 formed on the sensor surface 24 for generating a sensing signal in response to a predetermined physical stimulus. The compact sensing apparatus 20 further includes signal conditioning circuitry defining a signal conditioner 36, the signal conditioner 36 being formed in the signal conditioner surface 26 of the monolithic semiconductor substrate 22. The signal conditioner 36, moreover, is electrically connected to the sensor 34 for conditioning the sensing signal generated by the sensor 34 in response to the predetermined physical stimulus. A sensing apparatus formed on a monolithic substrate is illustrated in U.S. Pat. No. 5,670,886 to Applicants titled Method and Apparatus for Sensing Proximity or Position of an Object Using Near-Field Effects, the disclosures of which are incorporated herein in their entirety. As will be readily understood by those skilled in the art, the physical stimulus can be an electric field, a magnetic field, or a mechanical force.

[0032] A significant advantage of the present invention is the orientation of the sensor 34 relative to the signal conditioner 36. Preferably, the sensor 34 is oriented orthogonally to the signal conditioner 36. Orthogonal orientation reduces the lengthwise extent L of the sensing apparatus 20, making the device much more compact than conventional devices having same-plane sensor and signal conditioning circuitry. (See FIG. 2.) A sensor formed on a substrate and oriented orthogonally to a signal conditioner also formed on the substrate is illustrated in applicants' co-pending application titled Compact Sensing Having an Orthogonal Sensor Formed in a Monolithic Substrate and in U.S. Pat. No. 5,670,886 to applicants titled Method and Apparatus for Sensing Proximity or Position of an Object Using Near-Field Effects, the disclosures of which are incorporated herein in their entirety.

[0033] Moreover, according to the present invention, advantage can be taken of the fact that the circuitry required for the signal conditioner 36 is typically more extensive than that associated with the sensor 34. Specifically, because the height H and lateral extent W of the sensing apparatus 20 will be a function of the surface area of the sensor surface 24 when the sensor 34 is orthogonal to the signal conditioner 36, the sensor surface 24 preferably is smaller than the signal conditioner surface 26 to thereby reduce the height and lateral extend of the compact sensing apparatus 20. (See FIG. 2)

[0034] As further illustrated in FIG. 1, the signal conditioner 36 preferably is electrically connected to the sensor 34 via a conductive path comprising at least one integrated conductor 42 formed in the monolithic semiconductor substrate 22 and extending over an edge portion 44 of the monolithic semiconductor substrate 22, the edge specifically being the edge shared by the sensor surface 24 and the signal conditioner surface 36. The conductive path, moreover, preferably also includes at least one pair of metal conductors 46,48 formed on the monolithic semiconductor substrate 22. More specifically, one of the at least one pair of metal conductors 46 connects to the at least one integrated conductor 42 and extends along the sensor surface 24 to connect to the sensor 34 formed therein. The other of the at least one pair of metal conductors 48, then, preferably connects to the at least one integrated conductor 42 and extends along the signal conditioner surface 26 to connect to the signal conditioner 36 formed therein to thereby complete the conductive path between the sensor 34 and the signal conditioner 36.

[0035] Preferably, each of the at least one integrated conductors 42 is formed by heavily doping the monolithic semiconductor substrate 22 in at least one region of the monolithic semiconductor substrate 22 wherein that region extends over an edge portion of the monolithic semiconductor substrate 22 and the edge is that edge shared by the sensor surface and the signal conditioner surface. A conductor, such as a metal conductor, can then connect to the sensor 34 and extend from the sensor 34 along the sensor surface 24 to one of the at least one edge-positioned integrated conductors 42 to thereby form an electrical connection between the sensor and the integrated conductor. Similarly, another conductor—again, for example, a metal conductor—can connect to the signal conditioner 36 and extend therefrom along the signal conditioner surface 26 to the same at least one integrated conductors 42 to thereby electrically connect the signal conditioner 36 to the integrated conductor 42. Thus, the sensor 24 and the signal conditioner jointly connect electrically to a same at least one integrated conductor 42 thereby completing the conductive path between the sensor 34 and the signal conditioner 36.

[0036] As illustrated in FIGS. 3-4, a sensor positioned orthogonally on the monolithic substrate 22 can sense electrical or magnetic fields, as well as mechanical forces, oriented perpendicularly or horizontally relative to the sensor, depending on the nature of the sensor 34. More specifically an orthogonal sensor 34 will sense electrical E or magnetic fields B, or mechanical forces F, oriented perpendicularly to the planar surface of the sensor 34. (See FIG. 3) Alternatively, a transverse sensor 34′ can sense electrical E or magnetic fields B, or mechanical forces F that are oriented parallel to the planar surface of the sensor 34′. (See FIG. 4) In each case the field or force is generated by an entity 50 spaced apart from the sensing apparatus mounted sensor 34,34′.

[0037] FIG. 5 illustrates a second embodiment of the present invention wherein the conductive path between the sensor 134 and the signal conditioner 136 defines a first conductive path, and the sensing apparatus 120 further includes a second conductive path. The second conductive path, specifically, includes an electrical conductor 160 that is electrically connected to the signal conditioner 136 and extends therefrom to connect to a preselected electrical device 170 positioned apart from the sensing apparatus 120. Thus, the conductive path thereby forms a conductive path between the compact sensing apparatus 120 and the remotely positioned preselected electrical device 170. The preselected electrical device 170 preferably will be a sensing monitor. The compact sensing apparatus 120, as also illustrated in FIG. 5, can further include a mounting base 180 to which the monolithic substrate 122 is attached to thereby provide a separate or additional support structure underlying the substrate-mounted sensor 124 and substrate mounted signal conditioner 126.

[0038] As further illustrated in FIGS. 6, 6A the sensing apparatus 120 can further include a housing or other type of encapsulation extending over all or a portion of the sensing apparatus 120 to thereby encapsulate at least a portion of the signal conditioner 136 so as to provide a protective cover therefor. The electrical conductor 160 providing a conductive path between the signal conditioner 136 and a remotely positioned electrical device 170, then, extends through the encapsulation to thereby electrically connect the sensing apparatus 120 and the preselected electrical device 170.

[0039] FIG. 7 illustrates a third embodiment of the present invention, the sensing apparatus 220 having an encapsulation extending over the sensor 234 formed on the sensor surface 224 as well as the signal conditioner formed on the signal conditioning surface 226. With respect to a sensor 234 comprising a magnetoresistor or Hall element cell, the encapsulation preferably is a nonmagnetic material that partially encapsulates the monolithic semiconductor substrate 222, the sensor 234 formed in the substrate, and the signal conditioner 236 formed in the substrate. Moreover, as illustrated, a sensing apparatus 220 having a sensor 234 comprising a magnetoresistor or Hall element cell further comprises a magnetic encapsulation 228 that partially encapsulates the monolithic semiconductor substrate 222, the sensor 234 formed in the substrate 222, and the signal conditioner 236 formed in the substrate 222. More specifically, the magnetic encapsulation 228 is behind the planar surface of the sensor 234 formed on the sensor surface 224 and the magnetic material of the magnetic encapsulation 228 is preferably charged in a direction parallel to an imaginary straight line extending between the sensor 234 and the magnetic encapsulation 228, the line being generally perpendicular to both the planar surface of the sensor 234 and the edge of the magnetic encapsulation 228 that is closed or abuttingly in contact with the monolithic semiconductor substrate 222.

[0040] Further, the second conductive path, as illustrated in FIG. 7, preferably is provided by an output wire 262 and ground wire 264. An electrical connection with the signal conditioner 236 preferably is be made by contacting the output wire 262 and the ground wire 264 to wirebond pads 227, 229 formed on the monolithic substrate 222 and electrically connected to the signal conditioner 236 as also illustrated in FIG. 7. The connection between the wirebond pads 227, 229 and the output wire 262 and the ground wire 264, respectively, is preferably held in place by use of a conductive epoxy that causes the output wire 262 and the ground wire 264 to adhere to the wirebond pads 227, 229.

[0041] As with respect to the first embodiment, the sensors 134, 234 comprising the second and third embodiments of the invention likewise can be any of various types of sensing elements for generating a sensing signal in response to a host of physical stimuli. The sensor, for example, can be a magnetoresistor or a Hall effect cell for detecting magnetic fields B. The sensor alternatively can be capacitive transducer for detecting electrical fields E. Types of sensors also include ones for detecting mechanical forces F such as pressure sensors, flow sensors, and accelerometers. These and a host of other types of sensors can be accommodated with the present invention as will be readily apparent to those of ordinary skill in the relevant art.

[0042] FIGS. 1-7, moreover, illustrate method aspects of the present invention. The method for forming a compact sensing apparatus includes positioning a signal conditioner 36,136, 236 on a monolithic semiconductor substrate. The monolithic semiconductor, for example, can be cut from a wafer of semiconductor material on which a signal conditioner 36,136, 236 has been formed. Preferably, a plurality of signal conditioners will be formed on one wafer surface in order to efficiently form multiple sensing apparatuses 20, 120, 220. After the plurality of signal conditioners is formed on the wafer surface, the wafer surface is cut into multiple monolithic semiconductor substrates, each of which has a signal conditioner formed thereon. If the signal conditioner 36,136, 236 has been formed on the surface of the wafer and the wafer cut into an individual monolithic semiconductor substrate 22, 122, 222, the substrate (or each of a plurality of substrates) is then rotated. A sensor 34,134, 234 is then formed, the sensor 34,134, 234 and the signal conditioner 36, 136, 236, being electrically connected and oriented orthogonally relative to each other.

[0043] The method further includes forming at least one integrated conductor 42,142, 242 on the monolithic semiconductor substrate. Preferably, the at least one integrated conductor is formed by doping the monolithic semiconductor substrate with an appropriate trivalent, pentavalent, or other doping material for making the semiconductor conductive so as to thereby form the integrated conductor having the desired conductive properties for completing a conductive path between the sensor 34,134,234 and the signal conditioner 36,136,236. Using the at least one integrated conductor 42,142, 242 as an electrical juncture, the conductive path between the sensor 34,134, 234 and the signal conditioner 36,136, 236 is completed by electrically connecting the sensor 34,134, 234 to one of the at least one integrated conductors 42,142, 242 and electrically connecting the signal conditioner 36, 136, 236 to the same integrated conductor 42,142, 242 to thereby form the conductive path.

[0044] In the drawings and specification, there have been disclosed a typical preferred embodiment of the invention, and although specific terms are employed, the terms are used in a descriptive sense only and not for purposes of limitation. The invention has been described in considerable detail with specific reference to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the foregoing specification and as defined in the appended claims.

Claims

1. A compact sensing apparatus comprising:

a monolithic semiconductor substrate having a sensor surface and a signal conditioner surface, the sensor surface being smaller than the signal conditioner surface;
a sensor formed in the sensor surface of the monolithic semiconductor substrate for generating a sensing signal in response to a predetermined physical stimulus; and
a signal conditioner formed in the signal conditioner surface of the monolithic semiconductor substrate and electrically connected to the sensor for conditioning the sensing signal.

2. A compact sensing apparatus as defined in claim 1, wherein the signal conditioner is electrically connected to the sensor via an electrical connection comprising at least one integrated conductor formed in the monolithic semiconductor substrate and extending over an edge portion of the monolithic semiconductor substrate shared by the sensor surface and the signal conditioner surface.

3. A compact sensing apparatus as defined in claim 1, wherein the sensor and the signal conditioner are electrically connected via a conductive path comprising at least one integrated conductor formed in the monolithic semiconductor substrate and at least one pair of metal conductors formed on the monolithic semiconductor substrate, the at least one integrated conductor positioned to extend over an edge of the monolithic semiconductor substrate shared by the sensor surface and the signal conditioner surface, one of the at least one pair of metal conductors connected to the at least one integrated conductor and extending along the sensor surface to connect to the sensor formed therein, and the other of the at least one pair of metal conductors connected to the at least one integrated conductor and extending along the signal conditioner surface to connect to the signal conditioner formed therein to thereby provide the conductive path between the sensor and the signal conditioner.

4. A compact sensing apparatus as defined in claim 3, wherein each of the at least one integrated conductors is formed by heavily doping the monolithic semiconductor substrate in at least one region of the monolithic semiconductor substrate that extends over an edge portion of the monolithic semiconductor substrate shared by the sensor surface and the signal conditioner surface.

5. A compact sensing apparatus as defined in claim 4, wherein the conductive path between the sensor and the signal conditioner defines a first conductive path, and wherein the apparatus further includes a second conductive path, the second conductive path comprising an electrical conductor electrically connected to the signal conditioner and extending therefrom to connect to a preselected electrical device positioned remotely from the sensing apparatus to thereby form a conductive path between the compact sensing apparatus and the preselected electrical device.

6. A compact sensing apparatus as defined in claim 5, the apparatus further comprising a base on which the monolithic substrate is positioned for providing support thereto.

7. A compact sensing apparatus as defined in claim 6, the apparatus further comprising an encapsulation encapsulating at least a portion of the signal conditioner for providing a protective cover therefor, the electrical conductor extending through the encapsulation to thereby provide an electrical connection between the sensing apparatus and a preselected electrical device positioned outside the encapsulation.

8. A compact sensing apparatus as defined in claim 6, wherein the sensor is a magnetoresistor.

9. A compact sensing apparatus as defined in claim 6, wherein the sensor is a Hall element.

10. A compact sensing apparatus comprising:

a monolithic semiconductor substrate comprising a wafer surface and an orthogonal surface, the wafer surface and the orthogonal surface being oriented orthogonal to each other;
a sensor formed in the orthogonal surface of the monolithic semiconductor substrate for generating a sensing signal in response to a predetermined physical stimulus;
a signal conditioner formed in the wafer surface of the monolithic semiconductor substrate and electrically connected to the sensor for conditioning the sensing signal;
a base on which the monolithic semiconductor substrate is mounted for supporting the substrate-mounted sensor and signal conditioner;
an encapsulation connected to the base and encapsulating at least the signal conditioner mounted thereon to provide a protective covering for at least the signal conditioner; and
an electrical conductor electrically connected to the signal conditioner and extending outside the encapsulation for connecting the sensing apparatus to a preselected device.

11. A compact sensing apparatus as defined in claim 10, wherein the signal conditioner is electrically connected to the sensor via an electrical connection comprising at least one integrated conductor formed in the monolithic semiconductor substrate and extending over an edge portion of the monolithic semiconductor substrate shared by the orthogonal surface and the wafer surface.

12. A compact sensing apparatus as defined in claim 11, wherein each of the at least one integrated conductors is formed by heavily doping the monolithic semiconductor substrate in at least one region of the monolithic semiconductor substrate that extends over an edge portion of the monolithic semiconductor substrate shared by the wafer surface and the orthogonal surface.

13. A compact sensing apparatus as defined in claim 10, wherein the sensor and the signal conditioner are electrically connected via a conductive path comprising at least one integrated conductor formed in the monolithic semiconductor substrate and at least one pair of metal conductors formed on the monolithic semiconductor substrate, the at least one integrated conductor positioned to extend over an edge of the monolithic semiconductor substrate shared by the wafer surface and the orthogonal surface, one of the at least one pair of metal conductors connected to the at least one integrated conductor and extending along the orthogonal surface to connect to the sensor formed therein, and the other of the at least one pair of metal conductors connected to the at least one integrated conductor and extending along the wafer surface to connect to the signal conditioner formed therein to thereby provide the conductive path between the sensor and the signal conditioner.

14. A compact sensing apparatus as defined in claim 10, wherein the sensor is a magnetoresistor.

15. A compact sensing apparatus as defined in claim 10, wherein the sensor is a Hall element.

16. A compact magnetic sensing apparatus comprising a magnetic sensor formed in a monolithic semiconductor substrate to generate a sensing signal in response to a predetermined physical stimulus and a signal conditioner formed in the same substrate and positioned at a right angle relative to the magnetic sensor, the signal conditioner being responsive to the magnetic sensor to condition the sensing signal generated by the sensor.

17. A compact magnetic sensing apparatus as defined in claim 16, wherein the sensor and the signal conditioner are electrically connected via a conductive path comprising at least one integrated conductor formed in the monolithic semiconductor substrate.

18. A compact sensing apparatus as defined in claim 17, wherein each of the at least one integrated conductors is formed by heavily doping the monolithic semiconductor substrate in at least one region of the monolithic semiconductor substrate that extends over an edge portion of the monolithic semiconductor substrate.

19. A compact sensing apparatus as defined in claim 18, wherein the conductive path between the sensor and the signal conditioner defines a first conductive path, and wherein the apparatus further includes a second conductive path, the second conductive path comprising an electrical conductor electrically connected to the signal conditioner and extending therefrom to connect to a preselected electrical device positioned remotely from the sensing apparatus to thereby form a conductive path between the compact sensing apparatus and the preselected electrical device.

20. A compact sensing apparatus as defined in claim 16, wherein the sensor and the signal conditioner are electrically connected via a conductive path comprising at least one integrated conductor formed in the monolithic semiconductor substrate and at least one pair of metal conductors formed on the monolithic semiconductor substrate.

21. A compact sensing apparatus as defined in claim 20, wherein each of the at least one integrated conductors is formed by heavily doping the monolithic semiconductor substrate in at least one region of the monolithic semiconductor substrate that extends over an edge portion of the monolithic semiconductor substrate.

22. A compact sensing apparatus as defined in claim 21, wherein the conductive path between the sensor and the signal conditioner defines a first conductive path, and wherein the apparatus further includes a second conductive path, the second conductive path comprising an electrical conductor electrically connected to the signal conditioner and extending therefrom to connect to a preselected electrical device positioned remotely from the sensing apparatus to thereby form a conductive path between the compact sensing apparatus and the preselected electrical device.

23. A compact sensing apparatus as defined in claim 16, the apparatus further comprising a base on which the monolithic substrate is positioned for providing support thereto.

24. A compact sensing apparatus as defined in claim 23, the apparatus further comprising an encapsulation encapsulating at least a portion of the signal conditioner for providing a protective cover therefor.

25. A compact sensing apparatus as defined in claim 24, wherein the encapsulation defines a protective encapsulation of nonmagnetic material that partially encapsulates the monolithic semiconductor substrate, the sensor formed in the substrate, and the signal conditioner formed in the substrate, and wherein the apparatus further comprises a magnetic encapsulation partially that partially encapsulates the monolithic semiconductor substrate, the sensor formed in the substrate, and the signal conditioner formed in the substrate.

26. A compact sensing apparatus as defined in claim 16, wherein the sensor is a magnetoresistor.

27. A compact sensing apparatus as defined in claim 16, wherein the sensor is a Hall element.

28. A compact sensing apparatus comprising a sensor formed in a monolithic semiconductor substrate to generate a sensing signal in response to a predetermined physical stimulus and a signal conditioner positioned at a right angle relative to the sensor, the signal conditioner being responsive to the sensor to condition the sensing signal generated by the sensor.

29. A compact sensing apparatus as defined in claim 28, wherein the sensor and the signal conditioner are electrically connected via a conductive path comprising at least one integrated conductor formed in the monolithic semiconductor substrate and at least one pair of metal conductors formed on the monolithic semiconductor substrate.

30. A compact sensing apparatus as defined in claim 29, wherein each of the at least one integrated conductors is formed by heavily doping the monolithic semiconductor substrate in at least one region of the monolithic semiconductor substrate that extends over an edge portion of the monolithic semiconductor substrate.

31. A compact sensing apparatus as defined in claim 30, wherein the conductive path between the sensor and the signal conditioner defines a first conductive path, and wherein the apparatus further includes a second conductive path, the second conductive path comprising an electrical conductor electrically connected to the signal conditioner and extending therefrom to connect to a preselected electrical device positioned remotely from the sensing apparatus to thereby form a conductive path between the compact sensing apparatus and the preselected electrical device.

32. A compact sensing apparatus as defined in claim 31, the apparatus further comprising a base on which the monolithic substrate is positioned for providing support thereto.

33. A compact sensing apparatus as defined in claim 32, the apparatus further comprising an encapsulation encapsulating at least a portion of the signal conditioner for providing a protective cover therefor.

34. A method for forming a compact sensing apparatus comprising the steps of positioning a sensor on a monolithic semiconductor substrate and positioning a signal conditioner on the same monolithic semiconductor substrate, the sensor and the signal conditioner being electrically connected and oriented orthogonally relative to each other.

35. A method as defined in claim 34, the method further comprising forming at least one integrated conductor on the monolithic semiconductor substrate.

36. A method as defined in claim 35, wherein the at least one integrated conductor is formed by doping the monolithic semiconductor substrate.

37. A method as defined in claim 34, the method further comprising forming at least one pair of conductors on the monolithic semiconductor substrate.

38. A method as defined in claim 37, wherein each of the pair of conductors is a metal conductor, one of the at least one pair of conductors being attached to the sensor and extending therefrom to connect to an integrated conductor and the other of the at least one pair of conductors being attached to the signal conditioner and extending therefrom to connect to the same integrated conductor.

39. A method for forming a compact sensing apparatus comprising positioning a sensor on a monolithic semiconductor substrate, the sensor being oriented orthogonally to a signal conditioner on the same monolithic semiconductor substrate.

40. A method as defined in claim 39, the method further comprising electrically connecting the sensor to the signal conditioner by forming a conductive path between the sensor and the signal conditioner, the conductive path being formed by doping the monolithic semiconductor to form at least one integrated conductor and electrically connecting the sensor to one of the at least one integrated conductors and electrically connecting the signal conditioner to the same integrated conductor to thereby form the conductive path.

Patent History
Publication number: 20020167312
Type: Application
Filed: May 1, 2002
Publication Date: Nov 14, 2002
Inventors: Marshall E. Smith (Eaton, FL), Richard W. Stettler (Winter Haven, FL), Peter U. Wolff (Winter Haven, FL)
Application Number: 10136466
Classifications
Current U.S. Class: Semiconductor Type Solid-state Or Magnetoresistive Magnetometers (324/252); Hall Plate Magnetometers (324/251)
International Classification: G01R033/06; G01R033/02;