Sensing system and method using galvanic isolation - Patents.com

Abstract

The sensor system includes a plurality of electric potential sensors. Each of the electric potential sensors has a sensor area of ​​less than one square centimeter. Each of the electric potential sensors includes one working electrode. Each one of the electric potential sensors is galvanically isolated from all other ones of the electric potential sensors to avoid measurement crosstalk between the plurality of electric potential sensors. The sensor system further includes a plurality of sensor control subunits. Each of the sensor control subunits is communicatively connected to a particular corresponding one of the plurality of electric potential sensors. Each one of the sensor control subunits is galvanically isolated from all other ones of the sensor control subunits to avoid measurement crosstalk between the plurality of sensor control subunits. The sensor system further includes a main control unit communicatively connected to each of the plurality of sensor control subunits.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application is a PCT application related to and claims the benefit of commonly owned, co-pending U.S. Provisional Application No. 63 / 299,308, filed on January 13, 2022, and entitled "System and Method for Continuous Multi-Parameter Recording Using Galvanically Isolated Circuits," the contents of which are incorporated herein by reference in their entirety.

[0002] The present disclosure relates to a sensor device that includes a plurality of sensor microprobes. [Background technology]

[0003] Bioanalyte sensing using microprobes has the advantage of being minimally invasive. Microsensing systems, such as sensors mounted on microneedles, microprobes, and neural probes, are commonly used in healthcare applications (among other applications). Minimally invasive techniques have the dual advantage of being less painful and less susceptible to infection. However, sensors positioned at minute distances from each other may be subject to crosstalk, which may affect the quality of data acquired by such sensors. Summary of the Invention [Means for solving the problem]

[0004] This Summary is a high level overview of various aspects of the invention and introduces certain concepts that are described in more detail in the Detailed Description section below. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used alone to determine the scope of the claimed subject matter. The claimed subject matter should be understood by reference to the entire specification, any or all drawings, and appropriate portions of each claim.

[0005] In some embodiments, the sensor system includes a plurality of potential sensors, each of the potential sensors having a sensor area of ​​less than one square centimeter, each of the potential sensors including one working electrode, and each one of the potential sensors being galvanically isolated from every other of the potential sensors to avoid measurement crosstalk between the multiple potential sensors. The sensor system further includes a plurality of sensor control subunits, each of the sensor control subunits communicatively connected to a particular corresponding one of the plurality of electric potential sensors, and each one of the sensor control subunits galvanically isolated from every other of the sensor control subunits to avoid measurement crosstalk between the plurality of sensor control subunits. The sensor system further includes a main control unit communicatively connected to each of the plurality of sensor control subunits.

[0006] In some embodiments, the potential sensor and the sensor control subunit are galvanically isolated from one another by a physical separation in which there is no electrical or dielectric contact between the potential sensor and the sensor control subunit. In some embodiments, the physical isolation is achieved by bulk physical isolation at the wafer level. In some embodiments, the physical separation is achieved by a dielectric or polymeric material.

[0007] In some embodiments, the main control unit and the multiple sensor control subunits are galvanically isolated from one another through the use of wireless or capacitive power transfer.

[0008] In some embodiments, the main control unit and the multiple sensor control subunits communicate with each other while remaining galvanically isolated by wireless, capacitive, optical or RF data signal transfer.

[0009] In some embodiments, the main control unit is connected to the multiple sensor control subunits by a switch configured to provide an active connection between the main control unit and only one of the multiple sensor control subunits at any one time. In some embodiments, each of the multiple sensor control subunits includes an internal power storage that provides power to the sensor control subunit when not actively connected to the main control unit.

[0010] In some embodiments, the main control unit and the sensor control subunit each include a respective microcontroller.

[0011] In some embodiments, the main control unit includes a microcontroller and each of the sensor control subunits does not include a microcontroller.

[0012] In some embodiments, each of the sensor control subunits includes an analog front end. In some embodiments, the analog front end includes an application specific integrated circuit.

[0013] In some embodiments, the main control unit and the multiple sensor control subunits are implemented on a printed circuit board.

[0014] In some embodiments, a support layer is positioned between (1) the printed circuit board and (2) the main control unit and the multiple sensor control subunits. In some embodiments, the main control unit and the multiple sensor control subunits are secured to the support layer by a non-dielectric adhesive.

[0015] In some embodiments, each of the potential sensors includes only one working electrode.

[0016] In some embodiments, each of the potential sensors does not include a reference electrode. [Brief description of the drawings]

[0017] Several embodiments of the present disclosure are described herein, by way of example only, with reference to the accompanying drawings, in which: FIG. 1 is a schematic diagram of a method for manufacturing a semiconductor device according to the present invention; FIG. 2 is a schematic diagram of a semiconductor device according to the present invention;

[0018] [Figure 1A] 1 illustrates an exemplary embodiment of a sensor array. [Figure 1B] 1 illustrates an exemplary embodiment of a number of sensors. [Figure 2A] 1 shows a diagram of a wafer level stack configuration of a multi-layer assembly structure. [Figure 2B] 1 illustrates an exemplary sensor array. [Figure 3A] 1 illustrates an exemplary sheet of material for forming a support layer. [Figure 3B] 1 shows two exemplary sensors bonded to a support layer. [Figure 4] 1 shows a circuit diagram of an exemplary sensor device. [Diagram 5] 1 shows a circuit diagram of an exemplary sensor device. [Figure 6] 1 shows a circuit diagram of an exemplary sensor device. [Figure 7A] A diagram showing the operation of virtual floating voltage control is shown. [Figure 7B] A diagram showing the operation of virtual floating voltage control is shown. [Figure 7C] A diagram showing the operation of virtual floating voltage control is shown. [Figure 8] 1 illustrates an exemplary embodiment of a sensing device. [Figure 9] 1 illustrates an exemplary embodiment of a sensing device. [Figure 10] 1 illustrates an exemplary embodiment of a sensing device. [Figure 11]1 illustrates an exemplary embodiment of a sensing device. [Figure 12] 1 illustrates an exemplary embodiment of a sensing device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The following description of preferred embodiments is merely exemplary in nature and is not intended to limit the present invention, its application or use in any way. Throughout, range descriptions are used as shorthand for describing all values ​​within the range. Any value within the range can be selected as the end of the range. Furthermore, all documents cited herein are incorporated herein by reference in their entirety. In the event of a discrepancy in definition between this disclosure and the cited documents, this disclosure shall prevail.

[0020] The description of illustrative embodiments according to the principles of the invention is intended to be read in connection with the accompanying drawings and should be considered as part of the entire written description. In describing the embodiments of the invention disclosed herein, references to directions or orientations are intended merely for convenience of explanation and are in no way intended to limit the scope of the invention.

[0021] Relative terms such as "lower," "upper," "horizontal," "vertical," "top," "down," "upper," "lower," "left," "right," "top," "bottom," and derivatives thereof (e.g., "horizontal," "downward," "upward," etc.) should be construed to refer to the orientation shown in the description or drawings being discussed. These relative terms are for convenience of description and do not require that the device be constructed or operated in a particular orientation unless expressly indicated.

[0022] The terms "attach," "affix," "connect," "couple," "interconnect," "mount," and similar terms refer to a relationship in which structures are fixed or attached to one another, either directly or indirectly through intervening structures, and, unless otherwise specified, refer to both movable and fixed attachments or relationships.

[0023] As used in the specification and claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0024] Spatial or directional terms such as "left," "right," "inside," "outside," "up," "down," etc. should not be considered limiting, and the present invention may contemplate various alternative orientations.

[0025] All numbers used in the specification and claims should be understood in any instance as being modified by the term "about," which refers to a range of plus or minus ten percent of the stated value.

[0026] Unless otherwise stated, all ranges or ratios disclosed herein should be understood to encompass any sub-ranges or ratios contained therein. For example, a range stated as "1 to 10," or a ratio stated as "1 to 10," should be considered to include all sub-ranges between (and including) a minimum value of 1 and a maximum value of 10, i.e., all sub-ranges or ratios beginning with a minimum value of 1 or greater and ending with a maximum value of 10 or less, including, but not limited to, 1 to 6.1, 3.5 to 7.8, 5.5 to 10, etc.

[0027] The terms "first," "second," and the like are not intended to refer to a particular hierarchy or order, but instead refer to different conditions, characteristics, or elements.

[0028] All documents referenced herein are incorporated by reference in their entirety.

[0029] The term "at least" means "greater than or equal to." The term "less than or equal to" means "less than or equal to."

[0030] As used herein, the term "microprobe" is interchangeable with the terms "microneedle" and "neural probe."

[0031] As used herein, the term "distal end" is defined as the most distal point or line of a unit. For example, the distal end of the tip of a microprobe is the portion of the microprobe that first contacts the skin.

[0032] Exemplary embodiments relate to, but are not limited to, compact, solid-state potential sensors employing only one working electrode. Examples of such sensors are described in WO 2021 / 009559 ("ELECTROCHEMICAL FET SENSOR") and WO 2021 / 144651 ("SENSING SYSTEM INCLUDING LAYERED MICROPROBE"), the contents of both of which are incorporated herein by reference in their entirety. In some embodiments, such sensors utilize the high sensitivity of silicon nanowire field effect transistors (SiNW FETs) to detect changes in working electrode potential driven by the interaction of the electrode surface with redox species or ions. In some embodiments, such sensors have an extremely small sensor area (e.g., about 50 μm×50 μm), and such extremely small sensors, when implemented with the use of dedicated electronic transducers, enable sensing of multiple metabolites and background signal subtraction. However, the inventors of this application have discovered that recording multiple analytes with closely spaced potential sensors (e.g., within a few centimeters of each other) with the same electrical ground can result in crosstalk between the different sensors. Potential sensors measure small changes in the working electrode potential using highly sensitive field effect transistors placed in close proximity to the working electrodes for signal amplification. Some of these sensing systems do not include a reference electrode to which a given sensor signal can be differentially referenced. Thus, in the case of mixed signals arising from two or more different working electrodes, the connected field effect transistors may sense the average / mixed potential change of all the separate working electrodes.

[0033] Exemplary embodiments described herein relate to electrical decoupling of various field-effect transistor-based sensors, including actuation electrodes and backgates. In other embodiments, similar platforms and methods using galvanic isolation are applicable to other types of multi-sensor arrays that exhibit signal crosstalk. In some embodiments, such decoupling separates the signals of various sensors of a single sensor device, even when such sensors are in close proximity to each other in a liquid medium (e.g., within a millimeter of each other). In some embodiments, galvanic isolation primarily blocks current flow between two differentially grounded electrical circuits. In some embodiments, complete wireless galvanic isolation, as described herein, also separates (e.g., completely separates) relative potential interactions that may interfere with potentiometric sensors. In some embodiments, galvanic isolation (e.g., complete galvanic isolation) is utilized to avoid sensor crosstalk between sensor arrays in a common buffer / solution and in close proximity in a non-reference sensing setup.

[0034] In some embodiments, different sensors, such as field effect transistor type sensors, positioned on the same conductive or dielectric substrate may experience potential interference, particularly if their individual gates are not positioned in close proximity (e.g., less than 1 μm) to the FET channel of the corresponding sensor. In some embodiments, interference between sensors can be significantly reduced by inserting a non-dielectric insulation, such as an air gap, polymer, etc., between the sensors. In some embodiments, crosstalk prevention allows simultaneous recording of multiple parameters by different sensors in the sensor array. In some embodiments, analog or digital galvanic isolation can be achieved according to one of the embodiments described below.

[0035] In some embodiments, a silicon-on-insulator (SOI) substrate includes a relatively thin (e.g., having a thickness on the order of 100 nanometers to a few micrometers) buried oxide dielectric insulator layer. In some embodiments, such a buried oxide dielectric insulator allows propagation of electrical potentials across the buried oxide layer, which disrupts galvanic isolation of the electrical potentials. FIG. 1A illustrates an exemplary embodiment of a sensor array 100 including multiple sensors 110, 120, 130, 140 formed on a single substrate. In some embodiments, to provide sufficient galvanic isolation to prevent crosstalk, the conductive elements are separated from the dielectric layer, thereby achieving sufficient galvanic isolation. FIG. 1B illustrates an exemplary embodiment of multiple sensors 150, 160, 170 that are galvanically isolated (e.g., by air gaps). As shown in FIG. 1B, the sensors 150, 160, 170 are separated from the wafer 180 and illustrated on a bottom tape 190 that holds the sensors 150, 160, 170 in a fixed position relative to one another for assembly into a sensor array as described herein. In the embodiment shown in FIG. 1B, the sensors 150, 160, 170 are sized to 50 micrometers. Additionally, in some embodiments, a different back-gate bias voltage is applied to each sensor in the sensor array to change the transistor characteristics of each sensor, thereby altering its electrochemical properties. In some embodiments, physical separation of the substrate underlying each sensor's back-gate (e.g., galvanic separation of each back-gate) allows for the application of such independent sensor-specific voltages. In some embodiments, galvanic isolation of the sensor probes can also be achieved by the use of a thicker dielectric (e.g., having a thickness on the order of greater than 100 micrometers), such as, for example, silicon oxide or other oxides, or by the inclusion of a thin (e.g., on the order of greater than 0.1 nanometers) non-dielectric material, such as, for example, a non-dielectric polymer such as polyimide or SU-8 photoresist, which would provide a gap between the probes.

[0036] In some embodiments, the sensors are positioned on a support substrate (e.g., a rigid or flexible support substrate) in a wafer-level setup to achieve physical separation (e.g., galvanic isolation) of adjacent sensors while maintaining constant relative positions of adjacent sensors. In some embodiments, the support layer comprises a non-dielectric material, a dielectric material, or a metal, and is insulated from the sensor itself by a polymer and a non-dielectric adhesive. For example, in some embodiments, the sensor chip is positioned on a dielectric or conductive support substrate that is pre-coated with a non-dielectric layer, such as, for example, a polymer adhesive. In some embodiments, any number of sensors (e.g., two sensors, three sensors, or more sensors) are physically separated from each other (e.g., galvanically isolated from each other) and mounted on a common support layer using a polymer and a non-dielectric adhesive layer. In some embodiments, the manufacturing process includes depositing an adhesive (e.g., a polymer and a non-dielectric adhesive) on the support substrate at the wafer level, bonding (by the deposited adhesive) the support substrate to an etched and separated silicon wafer containing the sensors, and cutting the support substrate. In some embodiments, the support layer is cut using a laser or other mechanical or chemical cutting process. In some embodiments, a wafer level printed circuit board is bonded underneath the support layer to provide electrical connectivity so that the laser cut slots allow direct wire bonding of the silicon chip to the printed circuit board through these slots.

[0037] FIG. 2A shows an illustration of a wafer-level stack configuration of a multi-layer assembly structure, as described above. The structure 200 shown in FIG. 2A includes a complementary metal oxide semiconductor (CMOS) type silicon wafer 210. In the embodiment shown in FIG. 2A, the wafer 210 is bonded to a support layer 220. In some embodiments, the support layer 220 includes a metal. In some embodiments, the support layer 220 includes stainless steel. In some embodiments, the support layer 220 includes other flexible or rigid materials that can mechanically support the wafer 210. In some embodiments, an adhesive (e.g., polymer and non-dielectric adhesives) bonds the wafer 210 to the support layer 220 as described above. FIG. 2A shows an adhesive tape 230 that is used to hold the wafer 210 and transfer the wafer 210 onto the support layer 220. As shown in FIG. 2A, the two-layer structure (e.g., including the wafer 210 and the support layer 220) is then mounted to a wafer-level printed circuit board 240. In some embodiments, the mounting to the wafer-level printed circuit board is performed using an adhesive.

[0038] FIG. 2B illustrates a sensor array 250. In some embodiments, the sensor array 250 includes a wafer layer (e.g., similar to the wafer 210 described above) that includes three sensors 262, 264, 266 that are galvanically isolated from one another prior to separation. In the embodiment illustrated in FIG. 2B, the sensor array 250 includes a support layer 270 (e.g., shown in cutaway view, similar to the support layer 220), which includes slots to allow wire bonding of the wafer 260 (e.g., including the sensors 262, 264, 266) to a printed circuit board 280 (e.g., similar to the printed circuit board 240) located at the bottom. In some embodiments, the printed circuit board 280 includes bond pads 282 positioned on the top side of the printed circuit board 280 (e.g., the side facing the support layer 270) and facing the openings in the support layer 270. In some embodiments, the wafer 260 includes connectors 268 facing downward (e.g., toward the support layer 270). In some embodiments, by connecting connectors 268 to bond pads 282 (e.g., bond wires 290 (only sensor 264 is shown for clarity)), the sensors 262, 264, 266 formed from the wafer 260 can communicate with an electronic reading system via the printed circuit board 280 after the sensor array 250 is separated.

[0039] FIG 3A shows a sheet 320 of material for forming a support layer, such as support layer 220 described above. In the embodiment shown in FIG 3A, the material is stainless steel, but as described above, in other embodiments, other materials may be used. As shown in FIG 3A, the sheet 320 is cut (e.g., laser cut) into several portions 322 (for clarity, only one of the portions 322 is shown in detail in FIG 3B). Each of the portions 322 is sized and shaped to form the support layer 220 for a single sensor array.

[0040] Figure 3B illustrates two physically separate silicon wafer-based sensors 360, 362 (e.g., sensors fabricated as described above with reference to Figure 1B) bonded to a support layer 370 with an adhesive 380. In the embodiment illustrated in Figure 3B, the support layer 370 comprises stainless steel, although as described above, in other embodiments the support layer may comprise other suitable materials. In the embodiment illustrated in Figure 3B, the adhesive 380 is a non-dielectric polymer adhesive, although in other embodiments the adhesive may comprise other suitable non-dielectric adhesives.

[0041] Various embodiments described herein employ various electronic setups to provide galvanic isolation between various sensors, thereby preventing crosstalk as described herein. In some embodiments, galvanic isolation is provided using an inductive power supply or other wireless power transfer connection, and data (e.g., analog or digital) is transferred using optical isolators, RF transmission, inductive, capacitors, or other wireless data transfer connections. FIG. 4 shows a circuit diagram for such a device 400, including a main module (e.g., main control unit) 410 and two sub-modules (e.g., sensor control sub-units) 450, 452. In some embodiments, each of the sub-modules 450, 452 includes a microcontroller controller unit (MCU) 454, a power management element 456, and one or more amplifiers 458 (for clarity, reference numbers are shown for only one of the sub-modules 450). In some embodiments, each of the sub-modules 450, 452 includes additional electronic hardware elements, such as multiplexers, memories, etc. In some embodiments, the one or more amplifiers 458 are connected to the sensor 470 (e.g., having physically separated sensing elements as described above). In some embodiments, each of the sub-modules 450, 452 is powered by a corresponding power supply 480, 482 that is galvanically isolated from one another. In some embodiments, as shown in FIG. 4, the power supplies 480, 482 are wireless inductive power supplies. In some embodiments, the sub-modules 450, 452 are connected to the main module 410 under galvanic isolation conditions. In some embodiments, the sub-modules 450, 452 are wirelessly connected to the main module 410. In some embodiments, the main module 410 includes an MCU 412 and a communication module 414. In some embodiments, the sub-modules 450, 452 are digitally connected to the main module 410 by galvanically isolated signal transducers 490, 492.In some embodiments, the galvanically isolated signal transducers 490, 492 include optical isolators or other galvanically isolated signal devices such as capacitors, Hall effect sensors, magnetoresistors, RF, transformers, relays, etc. In some embodiments, the main module 410 includes only an MCU and the sub-modules 450, 452 include only analog components. In the embodiment shown in Figure 4, the device 400 includes two sub-modules 450, 452 and two sensors 470, although one skilled in the art will appreciate that this quantity is merely exemplary and other embodiments may include other quantities of sub-modules and sensors.

[0042] In some embodiments, galvanic isolation is provided using temporal isolation. FIG. 5 shows a circuit diagram of a device 500 that provides galvanic isolation using temporal isolation. In some embodiments, the device 500 is generally similar to the device 400 described above, except as described below. In some embodiments, the device 500 includes two sub-modules 550, 552 connected to a main module 510. In some embodiments, the sub-modules 550, 552 are sequentially connected to the main module 510 using a galvanic switching system 530, so that only one of the sub-modules 550, 552 has an active connection with the main module 510 at any one time. In some embodiments, each sub-module 550, 552 includes a switched power element 572 (e.g., a hold capacitor or a rechargeable battery that serves as internal power storage) configured to apply a current and potential to the sub-module 550, 552 when temporarily disconnected from the main module 510. In some embodiments, the sensor data is transmitted continuously (e.g., while connected to the mains power supply or while disconnected from the mains power supply) via the galvanically isolated signal transducers 590, 592. In some embodiments, the galvanically isolated signal transducers 590, 592 include optical isolators, capacitors, Hall effect sensors, magnetoresistors, RF, transformers, or relays. In other temporal galvanic isolation embodiments, the main module 510 includes a single galvanically isolated signal transducer 590 that is selectively connected to one of the sub-modules 550, 552 at a time by a switching element located between the signal transducers 590, 592 and the sub-modules 550, 552.

[0043] In some embodiments, the sensor-specific sub-modules include only an analog "front end" and do not include a microcontroller controller unit. FIG. 6 shows a circuit diagram of a system 600 thus provided. In some embodiments, the system 600 includes a main module 610 and two sub-modules 650, 652. In some embodiments, each of the sub-modules 650, 652 includes a power management element 656 and one or more amplifiers 662. In some embodiments, each of the sub-modules 650, 652 includes additional electronic hardware elements such as multiplexers, memory, etc. In some embodiments, the one or more amplifiers 662 are connected to a sensor 670 (e.g., with physically separated sensing elements as described above). In some embodiments, rather than including an MCU included in the sub-modules 450, 452, the sub-modules 650, 652 include an Inter-Integrated Circuit (I2C) bus 654 that facilitates communication with the main module 610. In some embodiments, each of the sub-modules 650, 652 is powered by a corresponding power supply 680, 682 that is galvanically isolated from one another. In some embodiments, as shown in FIG. 6, the power supplies 680, 682 are wireless inductance power supplies. In some embodiments, the sub-modules 650, 652 are connected to the main module 610 under galvanic isolation conditions. In some embodiments, the sub-modules 650, 652 are wirelessly connected to the main module 610.

[0044] In some embodiments, to further benefit from the separation of the digital and analog front ends, some of the front end functionality is integrated directly into the physical sensor chip. For example, in some embodiments, the sensor chip is manufactured using CMOS fabrication and includes additional non-functional silicon area, so that some or all of the analog / digital components are integrated directly into the sensor silicon chip as part of the application specific integrated circuit (ASIC).

[0045] In some embodiments, the physical galvanic isolation of each sensor chip is performed in a MEMS deep etching step, which directly results in isolated integrated chips. In some embodiments, the fact that the sensor sub-modules are galvanically isolated in-situ and assembled at wafer level allows for highly accurate (e.g., less than 1 micron tolerance) and repeatable chip-to-chip distances. In some embodiments, chip-to-chip distances of less than 20 microns are achieved.

[0046] In some embodiments, having a predefined relative positioning between the probes as a result of wafer level assembly, and a high spatial correlation between the probes and the PCB layers of the chip, allows for highly efficient design and manufacturing of wireless power and data communication. Additionally, in some embodiments, having a predefined main module ASIC chip located in close proximity (e.g., within 50 microns) to the MEMS isolation etch enables low power Wi-Fi communication since the distance between the receiver and transducer is minimized and precisely predefined.

[0047] In some embodiments, virtual floating voltage control is implemented to facilitate integration of biosensors, such as electrochemical potentiometric FET-based sensors with variable backgate bias, with other application specific integrated circuit (ASIC) elements. As described herein, an exemplary field effect transistor-based sensor is implemented to sense chemical or biological analytes. In such sensors, the backgate voltage can be adjusted to configure the operation of the sensor, thereby tuning the sensor for sensing different analytical analytes. For example, in some cases, biological and chemical sensors use the bulk of the wafer (sometimes referred to as the "handle") as a connection point to a voltage source, such that the voltage source can be operated to apply a particular voltage to the backgate at a desired time. However, in some cases, tuning the backgate voltage in a sensor system with multiple sensors in close proximity to each other can create interference that can compromise the reliability of the sensor data. For example, integrating a biological or chemical sensor on a common substrate with an ASIC (such as a front-end analog ASIC or a mixed analog / digital ASIC as described herein) has the effect that any change to the shared handle potential will affect the performance of the ASIC analog / digital transistors, causing their threshold voltages to change, which may cause system instability and failure. Thus, in some embodiments, a floating virtual voltage control can be implemented to apply a constant potential or ground to the handle of such an integrated chip (thereby avoiding the associated potential instabilities as described above) and to allow tuning of the backgate to tune the performance of a given sensor to sense a desired analyte. In some embodiments, the floating voltage control involves grounding the backgate (or in other embodiments, maintaining the backgate at a fixed non-zero voltage) and shifting the potentials of other components of the same sensor (such as the potentials of the working electrode, source, and drain) in parallel with respect to the handle, thereby controlling the relative potential of a given backgate.Since the sensing performance of the sensor depends on the voltage of the backgate relative to other components, such a shifting operation adjusts the performance of the sensor while maintaining the backgate itself at a fixed voltage. For example, FIGS. 7A-7C show diagrams illustrating this effect. In FIGS. 7A-7C, the backgate is set to a fixed ground voltage, while the source voltage S, the drain voltage D, and the working electrode WG are adjusted in parallel with each other relative to the backgate voltage BG. In FIG. 7A, the virtual backgate voltage (e.g., the voltage of the backgate relative to the drain voltage D used as a reference point) is −1.5. In FIG. 7B, the virtual backgate voltage is 0. In FIG. 7C, the virtual backgate voltage is 1. Since the actual voltage of BG does not change, all other on-chip components, such as analog / digital components, are not affected by such changes. In some embodiments, the virtual voltage control described here can be implemented by software control (e.g., by controlling the voltage applied by a DAC).

[0048] In other embodiments, the chemical or biological FET-based sensor does not include virtual floating voltage control, which means an ungrounded backgate with a variable voltage. This ungrounded backgate system, when integrated with an analog / digital ASIC, requires that the backgate voltage of the sensor FET region (the backgate of the sensor) is isolated from the analog / digital ASIC, so that each component can be controlled separately while not affecting the other components. In such embodiments, backgate isolation can be achieved by: (1) physically isolating the wafer handle silicon bulk by dielectric or etching; (2) isolating the potential of various parts of the wafer handle by implanting different dopants to achieve N / P junctions; (3) adding a local backgate well (biased backgate dedicated to sub-FETs) under other components (e.g., sensors, ASICs, etc.); (4) adding a local backgate well under each transistor on the chip (e.g., sensors, ASICs, etc.) so that each transistor or transistor array (e.g., ADC, DAC, AMP, resistor, memory cell, etc.) can be individually controlled; (5) adding a backgate well above or below the buried oxide of a silicon-on-insulator wafer.

[0049] FIG. 8 illustrates one embodiment of a sensing device 800. In the embodiment illustrated in FIG. 8, the sensing device 800 includes three sensor probes 810, 820, and 830. The sensor probes 810, 820, and 830 are physically and galvanically isolated from one another as described herein. The sensor probes 810, 820, and 830 are mounted on a support layer 840. In some embodiments, the sensor probes 810, 820, and 830 are mounted on the support layer 840 using a non-dielectric adhesive as described herein. In some embodiments, a PCB layer is positioned "below" the support layer 840 (e.g., on the side of the support layer 840 opposite the sensor probes 810, 820, and 830), as described above with reference to FIGS. 2A-2B. In some embodiments, all assembly is performed at a wafer-level scale.

[0050] FIG. 9 illustrates one embodiment of a sensing device 900. In the embodiment illustrated in FIG. 9, the sensing device 900 includes three sensor probes 910, 920, 930. The sensor probes 910, 920, 930 are physically and galvanically isolated from one another as described herein. In some embodiments, the sensor probes 910, 920, 930 each include an individual sensor 912, 922, 932 positioned at an end of the individual sensor probe 910, 920, 920 and configured to be inserted into a sample solution or tissue. In some embodiments, each of the sensors 912, 922, 932 is a field effect transistor sensor. The sensor probes 910, 920, 930 each include an individual on-chip integrated analog front end 914, 924, 934 as described above with reference to FIG. 6. In some embodiments, each of the analog front ends 914, 924, 934 includes an ADC, a DAC, a voltage control unit, and an amplifier. In some embodiments, each of the analog front ends 914, 924, 934 is configured to provide a potential to the source, working electrode, and back gate of a corresponding one of the sensors 912, 922, 932, and to collect and amplify a current from a field effect transistor drain of a corresponding one of the sensors 912, 922, 932. In some embodiments, communication between each of the sensor probes 910, 920, 930 is performed using a raw output / input data architecture, such as, for example, I2C (Inter-Integrated Circuit). The sensing device 900 includes a main PCB 940. In some embodiments, each of the probes 910, 920, 930 is connected to the PCB 940 via a physical connection, such as, for example, wire bonding. In some embodiments, as shown in FIG. 9, each of the probes 910, 920, 930 includes four pads 916 (specifically identified for only the probe 910 for clarity) connected to four corresponding pads 942 on the PCB 940. In some embodiments, two of the pads 916 for each of the probes 910, 920, 930 provide power and the remaining two pads 916 provide data communication.In other embodiments, only two pads connect the PCB 940 to each of the probes 910, 920, 930, and power and data communication are provided through the same connection. In some embodiments, each of the sensor probes 910, 920, 930 is galvanically isolated at the PCB level via in-situ wireless power transfer, such as by inductive, capacitive, electromechanical, magneto-mechanical, or other methods of wireless power / energy transfer. In some embodiments, wireless energy transfer is achieved by coil-to-coil induction, which is added as a discrete component on the PCB 940 or integrated into a layer of the fabricated PCB 940, while the powering coil and receiving coil are separated by a PCB insulating layer. In some embodiments, bidirectional data communication is achieved through the same wireless power system or by separate conductive, capacitive, electro-optical, magnetic, or RF transducers. In some embodiments, the PCB 940 includes a battery 944, a microcontroller controller unit 946, and a communication interface 948 that allows communication with additional devices. In some embodiments, the communication interface 948 is a wireless communication interface. In some embodiments, the communication interface 948 includes Bluetooth, WiFi, Near Field Communication (NFC), NarrowBand Internet of Things (NB-loT), Long Range (LoRa), etc. In other embodiments, the PCB 940 also includes one or more multiplexers, power management, or memory. In other embodiments, the PCB 940 includes additional sensors, such as accelerometers, temperature sensors, electro-optical sensors for pulse oximetry, contact electrodes (e.g., ECG electrodes), or other types of sensors suitable for health monitoring and / or patient treatment prediction, etc. In some embodiments, the analog front-ends of the probes 910, 920, 930 are fabricated on separate silicon dies assembled on top of the silicon probe chip, and both are electrically connected in a manner such as flip-chip or similar for die-to-die electrical connections. In some embodiments, a support layer (e.g., a metal support layer) is present between the sensor probes 910, 920, 930 and the PCB 940 and is adhered by an adhesive (e.g., a non-dielectric adhesive), as described above with reference to at least FIG. 3B.

[0051] FIG. 10 illustrates one embodiment of a sensing device 1000. In the embodiment illustrated in FIG. 10, the sensing device 1000 includes three sensor probes 1010, 1020, 1030. The sensor probes 1010, 1020, 1030 are physically and galvanically isolated from each other as described herein. In some embodiments, each of the sensor probes 1010, 1020, 1030 includes an individual sensor 1012, 1022, 1032 positioned at an end of the individual sensor probe 1010, 1020, 1020 and configured to be inserted into a sample solution or tissue. In some embodiments, each of the sensors 1012, 1022, 1032 is a field effect transistor sensor. The sensing device 1000 includes a PCB 1040. In the embodiment of FIG. 10, each of the sensor probes 1010, 1020, 1030 is connected to the PCB 1040 in a wireless manner and without wired connections. In some embodiments, the PCB 1040 includes a battery 1042, a microcontroller controller unit 1044, and a communication interface 1046 that allows communication with additional devices. In some embodiments, the communication interface 1046 is a wireless communication interface. In some embodiments, the communication interface 1046 includes Bluetooth, WiFi, Near Field Communication (NFC), Narrow Band Internet of Things (NB-loT), Long Range (LoRa), etc. In other embodiments, the PCB 1040 also includes one or more multiplexers, power management, or memory. In some embodiments, each of the sensor probes 1010, 1020, 1030 includes at least one wireless connection element 1014, 1024, 1034, respectively, and the PCB 1040 includes at least one wireless connection element 1050, 1052, 1054 corresponding to each of the sensor probes 1010, 1020, 1030.In some embodiments, a first wireless connection between the PCB 1040 and each of the sensor probes 1010, 1020, 1030 provides power transfer (e.g., from a battery 1042), and a second wireless connection between the PCB 1040 and each of the sensor probes 1010, 1020, 1030 provides data transfer. In some embodiments, the first wireless connection between the PCB 1040 and each of the sensor probes 1010, 1020, 1030 provides both power transfer (e.g., from a battery 1042) and data transfer. In some embodiments, the analog front end (e.g., of each of the sensor probes 1010, 1020, 1030) is fabricated on a separate silicon die assembled on top of a silicon probe chip, and both are electrically connected in a manner such as flip-chip or similar for die-to-die electrical connections. In some embodiments, a support layer (e.g., a metal support layer) is present between the sensor probe 1010, 1020, 1030 and the PCB 1040 and is adhered by an adhesive (e.g., a non-dielectric adhesive) as described above with reference to at least FIG. 3B. In some embodiments, the wireless connection elements 1014, 1024, 1034 and / or the wireless connection elements 1050, 1052, 1054 are integrated into the sensor probe 1010, 1020, 1030 and / or the PCB 1040 during a CMOS fabrication step (e.g., to form silicon embedded metal coils for energy and / or data transfer from the sensor probe 1010, 1020, 1030 to / from the PCB 1040).

[0052] FIG. 11 illustrates one embodiment of a sensing device 1100. In the embodiment illustrated in FIG. 11, the sensing device 1100 includes three sensor probes 1110, 1120, 1130. The sensor probes 1110, 1120, 1130 are physically and galvanically isolated from one another as described herein. In some embodiments, each of the sensor probes 1110, 1120, 1130 includes an individual sensor 1112, 1122, 1132 positioned at an end of the individual sensor probe 1110, 1120, 1120 and configured to be inserted into a sample solution or tissue. In some embodiments, each of the sensors 1112, 1122, 1132 is a field effect transistor sensor. The sensing device 1100 includes a PCB 1140. In the embodiment of FIG. 11, each of the sensor probes 1110, 1120, 1130 is connected to the PCB 1140 in a wireless manner and without wired connections. In some embodiments, the PCB 1140 includes a battery 1142. In the embodiment shown in FIG. 11, the sensing device 1100 includes an application specific integrated circuit (ASIC) 1180 including a microcontroller controller unit (MCU) 1182 and a communication interface 1184. In some embodiments, the communication interface 1184 is a wireless communication interface. In some embodiments, the communication interface 1184 includes Bluetooth, WiFi, Near Field Communication (NFC), Narrow Band Internet of Things (NB-loT), Long Range (LoRa), etc. In some embodiments, the ASIC 1180 is fabricated from a silicon frame that is not directly part of the sensor probe 1110, 1120, 1130 or its analog front end. In some embodiments, each of the sensor probes 1110, 1120, 1130 includes a first wireless connection element 1114, 1124, 1134, respectively, and a second wireless connection element 1116, 1126, 1136, respectively.In some embodiments, the PCB 1140 includes wireless charging links 1150, 1152, 1154 configured to provide power to the respective sensor probes 1110, 1120, 1130 via the respective first wireless connection elements 1114, 1124, 1134. In some embodiments, the ASIC 1180 includes wireless data links 1190, 1192, 1194 configured to communicate data to and from the respective sensor probes 1110, 1120, 1130 via the respective second wireless connection elements 1116, 1126, 1136. In some embodiments, all silicon chips are fabricated from the same wafer and separated by deep etch separation, so that the distance between elements such as the second wireless connection elements 1116, 1126, 1136 and the wireless data links 1190, 1192, 1194 is controlled to improve the efficiency of such elements. In some embodiments, the MCU 1182 of the ASIC 1180 is located on a different die, so that the ASIC 1180 can be manufactured using an analog manufacturing process. In some embodiments, the PCB 1140 also includes one or more multiplexers, power management, or memory. In some embodiments, a support layer (e.g., a metal support layer) is present between the sensor probes 1110, 1020, 1030 and the PCB 1140 and is attached by an adhesive (e.g., a non-dielectric adhesive) as described above with reference to at least FIG. 3B. In some embodiments, the first wireless connection element 1114, 1124, 1134 and / or the second wireless connection element 1116, 1126, 1136 and / or the wireless charging link 1150, 1152, 1154 and / or the wireless data link 1190, 1192, 1194 are integrated into the sensor probe 1110, 1120, 1130 and / or the PCB 1140 and / or the ASIC 1180 during a CMOS fabrication step (e.g., to form silicon embedded metal coils for energy and / or data transfer from the sensor probe 1110, 1120, 1130 to / from the PCB 1140 and / or the ASIC 1180).

[0053] FIG. 12 illustrates one embodiment of a sensing device 1200. In the embodiment illustrated in FIG. 12, the sensing device 1200 includes three sensor probes 1210, 1220, 1230. The sensor probes 1210, 1220, 1230 are physically and galvanically isolated from one another as described herein. In some embodiments, each of the sensor probes 1210, 1220, 1230 includes an individual sensor 1212, 1222, 1232 positioned at an end of the individual sensor probe 1210, 1220, 1220 and configured to be inserted into a sample solution or tissue. In some embodiments, each of the sensors 1212, 1222, 1232 is a field effect transistor sensor. The sensing device 1200 includes a PCB 1240 and an application specific integrated circuit (ASIC) 1280. In the embodiment of FIG. 12, each of the sensor probes 1210, 1220, 1230 is connected to the ASIC 1280 in a wireless manner and without a wired connection. In some embodiments, the PCB 1240 includes a battery 1242 connected to the ASIC 1280. In the embodiment shown in FIG. 12, the ASIC 1280 includes a microcontroller controller unit (MCU) 1282 and a communication interface 1284. In some embodiments, the communication interface 1284 is a wireless communication interface. In some embodiments, the communication interface 1284 includes Bluetooth, WiFi, Near Field Communication (NFC), Narrow Band Internet of Things (NB-loT), Long Range (LoRa), etc. In some embodiments, the ASIC is fabricated from a silicon frame that is not directly part of the sensor probes 1210, 1220, 1230 or their analog front ends. In some embodiments, each of the sensor probes 1210, 1220, 1230 includes a first wireless connection element 1214 and a second wireless connection element 1216 (identified by reference number only for the sensor probe 1210 for clarity).In some embodiments, the ASIC 1280 includes wireless charging links 1286, 1288, 1290 configured to provide power to the respective sensor probes 1210, 1220, 1230 via the respective first wireless connection elements 1214. In some embodiments, the ASIC 1280 includes wireless data links 1292, 1294, 1296 configured to communicate data to and from the respective sensor probes 1210, 1220, 1230 via the respective second wireless connection elements 1216. In some embodiments, all silicon chips are fabricated from the same wafer and separated by deep etch separation, thereby controlling the distance between elements such as the second wireless connection elements 1216, the wireless data links 1290, 1292, 1294, and the like, improving the efficiency of such elements. In some embodiments, the MCU 1282 of the ASIC 1280 is located on a different die, such that the ASIC 1280 can be fabricated using analog manufacturing processes. In some embodiments, the PCB 1240 also includes one or more multiplexers, power management, or memory. In some embodiments, the ASIC 1280 and the sensor probes 1210, 1220, 1230 are connected by an insulating adhesive, so that all power and communication between the different modules (e.g., between the sensor probes 1210, 1220, 1230 and the ASIC 1280) is conducted wirelessly. In some embodiments, a support layer (e.g., a metal support layer) is present between the sensor probes 1210, 1220, 1230 and the ASIC 1280, and is attached by an adhesive (e.g., a non-dielectric adhesive) as described above with reference to at least FIG. 3B.In some embodiments, the first wireless connection element 1214 and / or the second wireless connection element 1216, and / or the wireless charging links 1286, 1288, 1290 and / or the wireless data links 1292, 1294, 1296 are integrated into the sensor probe 1210, 1220, 1230 and / or the ASIC 1280 during a CMOS fabrication step (e.g., to form silicon embedded metal coils for energy and / or data transfer from the sensor probe 1210, 1220, 1230 to / from the ASIC 1280).

[0054] In any of the embodiments described herein, the sensing device (e.g., a PCB of the sensing device, etc.) may include additional sensors. In some embodiments, the additional sensors may include an accelerometer, a temperature sensor, an electro-optical sensor for pulse oximetry, and / or contact electrodes (e.g., ECG electrodes). In some embodiments, the additional sensors are suitable for health monitoring and / or patient treatment prediction.

[0055] Various exemplary embodiments are described herein and illustrated in the accompanying drawings that include a particular number of sensors (and corresponding sensor-specific ancillary hardware), e.g., two sensors, three sensors, etc. Such quantities described throughout this disclosure are merely exemplary, and other embodiments can include any other number of sensors without departing from the general principles described herein with reference to the exemplary embodiments.

[0056] It is understood that features of the present disclosure may be described in the context of separate embodiments for clarity, or may be provided in a single embodiment. Conversely, various features of the present disclosure may be described in the context of a single embodiment for brevity, or may be provided separately, or in any subcombination, or may be provided in any other embodiment of the present disclosure as appropriate. Certain features described in the context of various embodiments are not to be construed as essential features of such an embodiment, unless the embodiment is infeasible without those elements.

Claims

1. A plurality of potential sensors; A plurality of sensor control subunits; a main control unit communicatively connected to each of the plurality of sensor control subunits; each of the potential sensors having a sensor area of ​​less than one square centimeter; Each of the potential sensors comprises an actuating electrode; each one of the potential sensors being galvanically isolated from every other one of the potential sensors to avoid measurement crosstalk between the multiple potential sensors; each of the sensor control subunits is communicatively connected to a particular corresponding one of the plurality of electric potential sensors; A sensor system, wherein each one of the sensor control subunits is galvanically isolated from every other of the sensor control subunits to avoid measurement crosstalk between the multiple sensor control subunits.

2. 10. The sensor system of claim 1, wherein the potential sensor and the sensor control subunit are galvanically isolated from one another by a physical separation in which there is no electrical or dielectric contact between the potential sensor and the sensor control subunit.

3. The sensor system of claim 2 , wherein the physical isolation is achieved by bulk physical isolation at the wafer level.

4. The sensor system of claim 2 , wherein the physical separation is achieved by a dielectric or polymeric material.

5. The sensor system of claim 1 , wherein the main control unit and the multiple sensor control sub-units are galvanically isolated from each other through the use of wireless or capacitive power transfer.

6. The sensor system of claim 1 , wherein the main control unit and the plurality of sensor control subunits communicate with each other while remaining galvanically isolated by wireless, capacitive, optical or RF data signal transfer.

7. 10. The sensor system of claim 1, wherein the main control unit is connected to the multiple sensor control subunits by a switch configured to provide an active connection between the main control unit and only one of the multiple sensor control subunits at any one time.

8. Each of the plurality of sensor control subunits includes an internal power storage; The sensor system of claim 7 , wherein the internal power storage provides power to the sensor control subunit when not actively connected to the main control unit.

9. The sensor system of claim 1 , wherein the main control unit and the sensor control subunit each comprise a respective microcontroller.

10. The main control unit comprises a microcontroller, The sensor system of claim 1 , wherein each of the sensor control subunits does not include a microcontroller.

11. The sensor system of claim 10 , wherein each of the sensor control subunits comprises an analog front end.

12. The sensor system of claim 11 , wherein the analog front end comprises an application specific integrated circuit.

13. The sensor system of claim 1 , wherein the main control unit and the plurality of sensor control subunits are implemented on a printed circuit board.

14. The sensor system of claim 13 , wherein a support layer is positioned between (1) the printed circuit board and (2) the main control unit and the plurality of sensor control subunits.

15. The sensor system of claim 14 , wherein the main control unit and the plurality of sensor control subunits are secured to the support layer by a non-dielectric adhesive.

16. The sensor system of claim 1 , wherein each of the electric potential sensors comprises only one working electrode.

17. The sensor system of claim 1 , wherein each of the potential sensors does not include a reference electrode.

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