CN107703198B - Cartridge and analyzer for fluid analysis - Google Patents

Abstract

Fluidic cartridges and methods of operation are described. The fluidic cartridge includes a substrate having a plurality of contact pads designed to electrically connect with an analyzer, a semiconductor chip having a sensor array, and a reference electrode. The fluidic cartridge includes a first fluidic channel having an inlet and connected to a second fluidic channel, the second fluidic channel aligned such that the sensor array and the reference electrode are disposed within the second fluidic channel. A first plug is disposed at the first inlet. The first plug includes a flexible material configured to be passed through by a capillary tube without leakage of fluid through the first plug. The invention also provides an analyzer for analyzing a fluid.

Description

Cartridge and analyzer for fluid analysis

Technical Field

Embodiments of the present invention relate generally to the field of semiconductor technology, and more particularly, to a cartridge and analyzer for fluid analysis.

Background

Biosensors are devices for sensing and detecting biomolecules and operate on the principles of electronic, electrochemical, optical and mechanical detection. Biosensors comprising a transistor are sensors that electrically sense the charge, photon or mechanical properties of a biological entity or biomolecule. The detection is carried out by detecting the biological entity or the biological molecule itself or by the interaction and reaction between a specific reactant and the biological entity/biological molecule. Such a biosensor can be manufactured using a semiconductor process, can convert an electrical signal quickly, and can be easily applied to Integrated Circuits (ICs) and MEMS.

The interaction of the biological sample itself and the biosensor can be a challenge. Typically, a fluid comprising a biological sample is pipetted directly over the sensing portion of the biosensor. This approach results in a large portion of the fluid sample being unusable and manual loading of each sensing zone is time consuming.

Disclosure of Invention

According to an aspect of the present invention, there is provided a fluid cartridge including: a substrate including a plurality of contact pads configured to be electrically connected to an analyzer, a semiconductor chip having a sensor array, and a reference electrode; a first fluid channel having a first inlet and connected to a second fluid channel, the second fluid channel aligned such that the sensor array and the reference electrode are disposed within the second fluid channel; a sample inlet for placing a sample within the path of the first or second fluid channel; a first plug disposed at the first inlet and comprising a flexible material configured to be traversed by a capillary tube without leakage of fluid through the first plug.

According to another aspect of the present invention, there is provided a fluid cartridge comprising: a first fluid channel having a first inlet and connected to a second fluid channel, the second fluid channel aligned such that the sensor array and the reference electrode are disposed within the second fluid channel; a sample inlet for placing a sample within the path of the first or second fluid channel; a first plug disposed at the first inlet and comprising a flexible material configured to be traversed by a capillary without leakage of fluid through the first plug, wherein the capillary is connected to an analyzer and the capillary traverses the first plug when the fluidic cartridge is in physical contact with the analyzer.

According to yet another aspect of the present invention, there is provided an analyzer configured to be connected to a fluidic cartridge, the analyzer comprising: a syringe arranged such that when the fluid cartridge is physically connected to the analyzer, a needle of the syringe is aligned with a corresponding input port of the fluid cartridge; an actuator configured to control operation of the injector; a sensing module configured to send and receive signals to and from the fluidic cartridge via a plurality of conductive pads when the fluidic cartridge is physically connected to the analyzer, wherein the plurality of conductive pads contact a corresponding plurality of conductive pads on the fluidic cartridge; and a processor electrically connected to the sensing module and configured to determine a concentration level of a given analyte from a sample in the fluidic cartridge based on a signal received from the fluidic cartridge.

Drawings

The various aspects of the invention are best understood from the following detailed description when read with the accompanying drawing figures. It should be noted that, in accordance with standard practice in the industry, various components are not drawn to scale. In fact, the dimensions of the various elements may be arbitrarily increased or reduced for clarity of discussion.

Fig. 1 illustrates a diagram of components of an exemplary biosensing cartridge.

FIG. 2 is a cross-sectional view of an exemplary dual gate backside sense FET sensor.

Fig. 3 is a circuit diagram of a plurality of FET sensors configured in an exemplary addressable array.

Fig. 4 is a circuit diagram of an exemplary addressable array of dual gate FET sensors and heaters.

Fig. 5 is a cross-sectional view of an exemplary dual gate backside sense FET sensor configured as a pH sensor.

Fig. 6A shows an example of ion binding to the receptor layer.

Fig. 6B shows the change in threshold voltage in an exemplary pH-based FET sensor.

Fig. 7 is a plan view of an exemplary biosensor chip.

Fig. 8 shows a series of cross-sectional views of a manufacturing process for mounting an exemplary biosensor chip to a handle layer.

FIG. 9 is a top view of a handle layer with an exemplary biosensor chip mounted to a substrate.

Fig. 10 is a schematic of an exemplary fluidic cartridge with an integrated biosensor chip.

Fig. 11 is a schematic view of some of the fluidic channels in an exemplary fluidic cartridge.

Fig. 12 is a schematic of an exemplary fluidic cartridge connected to an analyzer.

Fig. 13 is a flow chart of an exemplary method of using a fluid cartridge.

Fig. 14 is a cross-sectional view of an exemplary dual gate backside sensing biofet for detecting DNA.

Fig. 15A shows the binding force of DNA on the receptor surface.

Fig. 15B shows the variation of threshold voltage of an exemplary dual-gate backside sensing biofet based on paired analyte binding.

Fig. 16 is a cross-sectional view of an exemplary dual-gate backside sensing biofet with antibodies immobilized on its sensing layer.

Figure 17 shows the binding force of antigen and antibody on the receptor surface.

Fig. 18 is a flow diagram of an embodiment of a method 2100 of fabricating a BioFET device according to one or more aspects of the present disclosure.

Detailed Description

The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to limit the invention. For example, in the following description, forming a first feature over or on a second feature may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed and/or disposed between the first and second features such that the first and second features may not be in direct contact. Moreover, the present disclosure may repeat reference numerals and/or characters in the various examples. This repetition does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Also, spatially relative terms such as "below …," "below …," "lower," "above …," "upper," and the like may be used herein for ease of description to describe one element or component's relationship to another (or other) element or component as illustrated. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Term(s) for

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the embodiments in accordance with the present invention; methods, devices, and materials are now described. All patents and publications mentioned herein are incorporated herein by reference to describe and disclose the materials and methods in the publications used in connection with the invention.

The acronym "FET" as used herein refers to a field effect transistor. One very common type of FET is referred to as a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). Historically, MOSFETs have been planar structures created in and on a planar surface of a substrate, such as a semiconductor wafer. Recent advances in semiconductor fabrication have resulted in three-dimensional fin MOSFET structures.

The term "biofet" refers to a FET that includes an immobilized capture reagent layer that serves as a surface receptor to detect the presence of target analytes of biological origin. According to an embodiment, the biofet is a field effect sensor with a semiconductor transducer. One advantage of biofets is the prospect of label-free operation. In particular, biofets enable expensive and time consuming labeling operations to be avoided, such as labeling analytes with, for example, fluorescent or radioactive probes. One particular type of biofet described herein is a dual-gate backside sensing biofet. The analyte detected by a biofet is typically of biological origin such as, but not limited to, proteins, carbohydrates, lipids, tissue fragments or fractions thereof. In a more general sense, however, a biofet is part of a broader class of FET sensors, which can also detect any chemical compound (known in the art as a chemfet) or any other element (known in the art as an ISFET) including ions such as protons or metal ions. The present invention is intended to be applicable to all types of FET-based sensors ("FET sensors"). One particular type of FET sensor herein is a double-gate backside sense FET sensor ("DG BSS FET sensor").

"S/D" refers to the source/drain junctions that form two of the four terminals of the FET.

The expression "high k" refers to a high dielectric constant. In the field of semiconductor device structures and fabrication processes, high-k refers to greater than SiO₂I.e., a dielectric constant greater than 3.9.

The term "analysis" generally refers to a process or step involving physical, chemical, biochemical, or biological analysis, including but not limited to characterization, testing, measurement, optimization, separation, synthesis, addition, filtration, dissolution, or mixing.

The term "assay" (assay) generally refers to a process or step involving the analysis of a chemical substance or target analyte, and includes, but is not limited to, cell-based assays, biochemical assays, high throughput assays and screens, diagnostic assays, pH determination, nucleic acid hybridization assays, polymerase activity assays, nucleic acid and protein sequencing, immunoassays (e.g., antibody-antigen binding assays, ELISA, and iqPCR), bisulfite methylation assays for detecting methylation patterns of genes, protein assays, protein binding assays (e.g., protein-protein, protein-nucleic acid, and protein-ligand binding assays), enzyme assays, conjugated enzyme assays, kinetic measurements (e.g., protein folding kinetics and enzyme reaction kinetics), enzyme inhibitor and activator screening, chemiluminescent and electrochemiluminescent assays, fluorescent assays, nucleic acids, and protein-ligand binding assays, enzyme inhibitors, and activators, and the like, Fluorescence polarization and anisotropy assays, absorbance and colorimetric assays (e.g., Bradford assays, Lowry assays, Hartree-Lowry assays, Biuret assays, and BCA assays), chemical assays (e.g., for detecting environmental contaminants and contaminants, nanoparticles, or polymers), and drug discovery assays. The devices, systems, and methods described herein may use or employ one or more of these assays to be used with any of the designs described for FET sensors.

The term "liquid biopsy" generally refers to a biopsy sample obtained from a bodily fluid of a subject as compared to a tissue sample of the subject. The ability to perform assays using body fluid samples is generally more desirable than using tissue samples. Minimally invasive methods using body fluid samples have broad implications in terms of patient well-being, the ability to perform longitudinal disease monitoring, and the ability to obtain expression profiles even when tissue cells are not readily accessible (e.g. in the prostate). Assays for detecting a target analyte in a liquid biopsy sample include, but are not limited to, those described above. As a non-limiting example, a liquid biopsy sample may be subjected to a Circulating Tumor Cell (CTC) assay.

For example, capture reagents (e.g., antibodies) immobilized on FET sensors can be used to detect analytes of interest (e.g., tumor cell markers) in liquid biopsy samples using CTC assays. CTCs are cells that flow from a tumor into the vasculature and circulate in, for example, the blood. Typically, CTCs are present in blood circulation at very low concentrations. To determine CTCs, CTCs are enriched from patient blood or plasma by various techniques known in the art. CTCs can be stained for specific markers using methods known in the art, including but not limited to cell count (e.g., flow cytometry) based methods and IHC based methods. For the devices, systems, and methods described herein, CTCs can be captured or detected using capture reagents, or nucleic acids, proteins, or other cellular environments from CTCs can be targeted for target analytes for binding to or detection by the capture reagents.

When an analyte of interest is detected on or from CTCs, for example, an increase in expression or inclusion of the analyte of interest in the CTCs may help identify the subject as having a cancer that is likely to respond to a particular treatment (e.g., a cancer associated with the analyte of interest) or allow optimization of a treatment regimen with, for example, antibodies to the analyte of interest. CTC measurement and quantification can provide information about, for example, the stage of a tumor, response to treatment, disease progression, or a combination thereof. The information obtained from target analytes for detecting CTCs can be used, for example, as a pre-diagnostic, predictive, or pharmacodynamic biomarker. In addition, CTC assays for liquid biopsy samples may be used alone or in combination with additional tumor marker analysis of solid biopsy samples.

The term "identification" generally refers to a process of determining a characteristic of a target analyte based on its binding to a capture reagent whose characteristic (identity) is known.

The term "measuring" generally refers to a process of determining the amount, quantity, quality, or nature of a target analyte based on its binding to a capture reagent.

The term "quantifying" generally refers to the process of determining the amount or concentration of a target analyte based on its binding to a capture reagent.

The term "detecting" generally refers to the process of determining the presence or absence of a target analyte based on its binding to a capture reagent. Detection includes, but is not limited to, identification, measurement, and quantification.

The term "chemical" refers to a substance, compound, mixture, solution, emulsion, dispersion, molecule, ion, dimer, macromolecule such as a polymer or protein, biomolecule, precipitate, crystal, chemical moiety or group, particle, nanoparticle, reagent, reaction product, solvent, or fluid, any of which may exist in a solid, liquid, or gaseous state and is typically the object of analysis.

The term "reacting" refers to a physical, chemical, biochemical or biological transformation involving at least one chemical species, and typically (in the case of chemical, biochemical and biological transformation) breaking or forming one or more bonds, such as covalent, non-covalent, van der waals, hydrogen or ionic bonds. The term includes typical chemical reactions such as synthesis reactions, neutralization reactions, decomposition reactions, displacement reactions, reduction-oxidation reactions, precipitation, crystallization, combustion reactions, and polymerization reactions, as well as covalent and non-covalent bonding, phase changes, color changes, phase formation, crystallization, solubilization, luminescence, changes in light absorption or emission properties, temperature changes or heat absorption or emission, conformational changes, and folding or unfolding of macromolecules such as proteins.

As used herein, a "capture reagent" is a molecule or compound capable of binding a target analyte or target reagent, which may be attached directly or indirectly to a substantially solid material. The capture reagent can be a chemical substance, specifically a naturally occurring target analyte (e.g., an antibody, polypeptide, DNA, RNA, cell, virus, etc.) or any substance that can produce a target analyte, and the capture reagent can bind to one or more target analytes in an assay.

As used herein, a "target analyte" is a substance in a test sample to be detected using the present invention. The target analyte may be a chemical substance, in particular a naturally occurring capture reagent (e.g. an antibody, polypeptide, DNA, RNA, cell, virus, etc.) or any substance from which a capture reagent may be prepared, and the target analyte may bind to one or more capture reagents in the assay. "target analyte" also includes any antigenic substance, antibody, and combinations thereof. Target analytes may include proteins, peptides, amino acids, carbohydrates, hormones, steroids, vitamins, including those drugs administered for therapeutic purposes as well as those drugs administered for illicit purposes, bacteria, viruses, and metabolites or antibodies of any of the foregoing.

As used herein, "test sample" refers to a composition, solution, substance, gas or liquid that includes an analyte of interest that is detected and assayed using the present invention. The test sample may include other components in addition to the target analyte, which may have the physical properties of a liquid or gas, and may be of any size or volume, including, for example, a moving stream of liquid or gas. The test sample may comprise any substance other than the target analyte, as long as the other substance does not interfere with the binding of the target analyte to the capture reagent or the specific binding of the first binding component (member) to the second binding component. Examples of test samples include, but are not limited to, naturally occurring and non-naturally occurring samples or combinations thereof. Naturally occurring test samples may be synthetic or synthetic. Naturally occurring test samples include bodily or body fluids isolated from any location in or on the body of a subject, including, but not limited to, blood, plasma, serum, urine, saliva or sputum, spinal fluid, cerebrospinal fluid, pleural fluid, nipple aspirate, lymph fluid, respiratory, intestinal and genitourinary fluids, tears, saliva, breast milk, lymphatic fluid, semen, cerebrospinal fluid, intra-organ systemic fluid, ascites, tumor cyst fluid, amniotic fluid, and combinations thereof, as well as environmental or food related samples such as ground or waste water, soil extracts, air and pesticide residues.

The detected substances may include, for example, nucleic acids (including DNA and RNA), hormones, various pathogens (including biological agents that cause disease or illness in their host, such as viruses (e.g., H)₇N₉Or HIV), protozoa (e.g., malaria causing plasmodium) or bacteria (e.g., escherichia coli or mycobacterium tuberculosis)), proteins, antibodies, various drugs or therapeutic agents, or other chemical or biological substances including hydrogen or other ions, non-ionic molecules or compounds, polysaccharides, small chemical compounds such as chemical combinatorial library components (members), and the like. The parameters detected or determined may include, but are not limited to, for example, pH changes, lactose changes, concentration changes, particles per unit time, and other parameters where a fluid flows over the device over a period of time to detect particles, such as sparse particles.

As used herein, the term "immobilized" as used with respect to, for example, a capture reagent includes substantially attaching the capture reagent at the molecular level to a surface. For example, capture reagents may be immobilized to the surface of a substrate material using adsorption techniques including non-covalent interactions (e.g., electrostatic forces, van der waals forces, and dehydration of hydrophobic interfaces) as well as covalent bonding techniques, where functional groups or linkers (linkers) facilitate attachment of the capture reagents to the surface. The capture reagent may be immobilized to the surface of the substrate material based on the properties of the substrate surface, the medium carrying the capture reagent, and the properties of the capture reagent. In some cases, the surface of the substrate may first be modified to have functional groups bonded to the surface. The functional groups can then bind biomolecules or biological or chemical substances to immobilize them thereon.

The term "nucleic acid" generally refers to a group of nucleotides linked to each other by phosphodiester bonds, and refers to a naturally occurring nucleic acid to which naturally occurring nucleotides that occur in nature are linked, which may be, for example, DNA and/or RNA, wherein DNA includes deoxyribonucleotides having any of adenine, guanine, cytosine, and thymine linked to each other and/or RNA includes ribonucleotides having any of adenine, guanine, cytosine, and uracil linked to each other. Furthermore, non-naturally occurring nucleotides and non-naturally occurring nucleic acids are within the scope of the nucleic acids of the invention. Examples include Peptide Nucleic Acids (PNA), peptide nucleic acids having a phosphate group (PHONA), bridged nucleic acids/locked nucleic acids (BNA/LNA), and morpholino nucleic acids. Another example includes chemically altered nucleic acids and nucleic acid analogs, such as methylphosphonate DNA/RNA, phosphorothioate DNA/RNA, phosphoramidate DNA/RNA, and 2' -O-methyl DNA/RNA. Nucleic acids include those that may be altered. For example, phosphate groups, sugars and/or bases in nucleic acids can be labeled as desired. Any substance known in the art for nucleic acid labeling may be used for labeling. Examples include, but are not limited to, radioisotopes (e.g., 32P, 3H, and 14C), DIG, biotin, fluorescent dyes (e.g., FITC, Texas, cy3, cy5, cy7, FAM, HEX, VIC, JOE, Rox, TET, Bodipy493, NBD, and TAMRA), and luminescent substances (e.g., acridinium esters).

An aptamer as used herein refers to an oligonucleotide or peptide molecule that binds to a particular target molecule. The concept of using single-stranded nucleic acids (aptamers) as affinity molecules for protein binding was originally disclosed in 1990 (Ellington and Szostak 1990, 1992; Tuerk and Gold 1990) and in the presence of targets the aptamers fold into unique three-dimensional structures that bind to targets with high affinity and specificity based on the ability of short sequences. Eugene W.M Ng et al disclosed in 2006 that aptamers were the oligonucleotide ligands of choice for high affinity binding to molecular targets.

The term "antibody" as used herein refers to a polypeptide of the immunoglobulin family capable of non-covalently, reversibly and in a specific manner binding a corresponding antigen. For example, naturally occurring IgG antibodies are tetramers comprising at least two heavy (H) chains and two light (L) chains interconnected by disulfide bonds. Each heavy chain consists of a heavy chain variable region (abbreviated herein as VH) and a heavy chain constant region. The heavy chain constant region consists of three domains, CH1, CH2, and CH 3. Each light chain consists of a light chain variable region (abbreviated herein as VL) and a light chain constant region. The light chain constant region consists of one domain CL. The VH and VL regions can be further subdivided into hypervariable regions (referred to as Complementarity Determining Regions (CDRs)) interspersed with more conserved regions (referred to as Framework Regions (FRs)). Each VH and VL is composed of three CDRs and four FRs arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3 and FR 4. Three CDRs make up about 15-20% of the variable domain. The variable regions of the heavy and light chains include binding domains that interact with antigens. The constant regions of the antibodies may modulate the binding of the immunoglobulin to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component of a typical complementary system (C1q) (Kuby, Immunology,4th ed., Chapter 4.w.h.freeman & co., New York, 2000).

The term "antibody" includes, but is not limited to, monoclonal antibodies, human antibodies, humanized antibodies, chimeric antibodies and anti-idiotypic (anti-Id) antibodies (including, for example, anti-Id antibodies directed against an antibody of the invention). The antibody can be of any isotype/class (e.g., IgG, IgE, IgM, IgD, IgA, and IgY) or subclass (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA 2).

The term "polymer" refers to any substance or compound consisting of two or more building blocks ("mers") repeatedly connected to each other. For example, a "dimer" is a compound in which two synthetic building blocks have been joined together. Polymers include both condensation and addition polymers. Typical examples of condensation polymers include polyamides, polyesters, proteins, wool, silk, polyurethanes, cellulose, and silicones. Examples of addition polymers are polyethylene, polyisobutylene, polyacrylonitrile, poly (vinyl chloride) and polystyrene. Other examples include polymers with enhanced electrical or optical properties (e.g., nonlinear optical properties), such as electrically conductive or photorefractive polymers. Polymers include both linear and branched polymers.

Overview of the biosensing Cartridge

Fig. 1 shows an overview of various components that are integrated together to form an exemplary biosensing cartridge 102. Biosensing cartridge 102 can include a plurality of fluidic channels configured to control the flow of fluid toward and away from a sensing location where the presence of a target analyte can be detected.

In the exemplary embodiment, biosensing cartridge 102 includes an array of FET sensors 104. The FET sensor 104 constitutes a sensor component of the biosensing cartridge 102. The FET sensors 104 may be arranged in an array and individually addressed to detect binding events at the surface of the FET sensor sensing layer. In one embodiment, the FET sensor 104 comprises a dual gate backside FET sensor. In alternative embodiments, other types of FET sensor-based sensors may be used.

The biosensing cartridge 102 includes a biological interface 106. The bio-interface 106 may be connected to the dual-gate backside sense FET sensor 104 in order to perform detectable binding reactions at the surface of the dual-gate backside sense FET sensor 104. Various types of biomolecules may form part of the biological interface 106 such as DNA or RNA aptamers and antibodies, to name a few examples. Further details regarding biological interfaces and their associated chemical and biological forces will be discussed in detail herein.

The biosensing cartridge 102 includes various levels of chip packaging 108 to integrate the dual gate backside sense FET sensor chip into a fluidic environment. The biosensing cartridge 102 also includes a fluidic assembly 110 having microfluidic channels for managing the delivery of liquid to the FET sensors 104. Fluidic assembly 110 also includes a fluidic inlet for connecting with a fluid delivered from outside of biosensing cartridge 102.

The integration of the various components in the biosensing cartridge 102 results in a compact and portable platform that can be used for many individual biosensing applications. The use of FET sensors with integrated fluidic components can produce accurate results when low sample volumes are used. Further, the biosensing cartridge 102 can be configured to operate in a fully autonomous manner by the analyzer and then disposed of after use.

The description herein is divided into four main sections to describe the components of the biosensing cartridge 102 in more detail. The first section will describe the arrangement and fabrication of the dual gate backside biofet sensor 104. The second section will describe the packaging process. The third section will describe the fluidic component 110 and further describe the interaction between the biosensing cartridge 102 and the analyzer. The last section will provide details regarding biology and various biosensing applications using the dual-gate backside FET sensor 104.

Dual gate backside FET sensor

Dual-gated backside FET sensors utilize semiconductor fabrication techniques and biological capture reagents to form sensitive and easily arrayed sensors. While conventional MOSFETs have a single gate electrode connected to a single electrical node, dual gate backside sense FET sensors have two gate electrodes, each gate electrode connected to a different electrical node. A first of the two gate electrodes is referred to herein as a front-side gate and a second of the two gate electrodes is referred to herein as a back-side gate. Both the front-side gate and the back-side gate are configured such that in operation each can be charged and/or discharged and thereby each affect the electric field between the source/drain terminals of the dual-gate backside sense FET sensor. The front-side gate is conductive, is separated from the channel region by a front-side gate dielectric, and is configured to be charged and discharged by a circuit connected thereto. The back side gate is typically separated from the channel region by a back side gate dielectric and includes a biofunctionalized sensing layer disposed on the back side gate dielectric. The amount of charge on the back side gate is a function of whether a biometric response has occurred. In typical operation of a dual gate backside sense FET sensor, the front-side gate is charged to a voltage within a predetermined voltage range. The voltage of the front-side gate determines the corresponding conductivity of the channel region of the FET sensor. A relatively small change in charge on the back side gate changes the conductivity of the channel region. This change in conductivity indicates a biological recognition reaction.

One advantage of FET sensors is the prospect of label-free operation. In particular, FET sensors enable expensive and time consuming labeling operations to be avoided, such as labeling analytes with, for example, fluorescent or radioactive probes.

Referring to fig. 2, an exemplary dual gate backside sense FET sensor 200 is shown. The dual gate backside sense FET sensor 200 includes a control gate 202 formed over a substrate 214 and separated from the substrate 214 by an intermediate dielectric 215 disposed on the substrate 214. Substrate 214 also includes source region 204, drain region 206, and channel region 208 located between source region 204 and drain region 206. In an embodiment, the substrate 214 has a thickness between about 100nm and about 130 nm. Gate 202, source region 204, drain region 206, and channel region 208 may be formed using suitable CMOS process techniques. Gate 202, source region 204, drain region 206, and channel region 208 form a FET. An isolation layer 210 is disposed on a side of the substrate 214 opposite the gate 202. In one embodiment, the isolation layer 210 has a thickness of about 1 μm. In the present invention, the side of the substrate 214 on which the gate 202 is disposed is referred to as the "front side" of the substrate 214. Similarly, the side of substrate 214 on which isolation layer 210 is disposed is referred to as the "backside".

An opening 212 is provided in the isolation layer 210. The opening 212 may be substantially aligned with the gate 202. In other embodiments, the opening 212 is larger than the gate 202 and may extend over multiple dual gate backside sense FET sensors. An interface layer (not shown) may be disposed in the opening 212 located on the surface of the channel region 208. The interface layer is operable to provide an interface for positioning and immobilizing one or more receptors for detection of biomolecules or biological entities. Further details regarding the interface layer are provided herein.

The dual-gate backside sense FET sensor 200 includes electrical contacts to the drain region 206(Vd 216), the source region 204(Vs 218), the gate structure 202 (front-side gate 220), and/or the active region 208 (e.g., the backside gate 222). It should be noted that the backside gate 222 need not physically contact the substrate 214 or any interface layer above the substrate 214. Thus, while conventional FETs use a gate contact to control the conductance of the semiconductor between the source and drain (e.g., the channel), the dual-gate backside sense FET sensor 200 allows a receptor formed on opposite sides of the FET device to control the conductance, while the gate structure 202 provides another gate to control the conductance. Thus, the dual gate backside sense FET sensor 200 may be used to detect one or more specific biomolecules or biological entities in the ambient environment and/or in the opening 212, as discussed in more detail in various embodiments used herein.

The dual gate backside sense FET sensor 200 may be connected to additional passive components such as resistors, capacitors, inductors, and/or fuses; and other active components including P-channel field effect transistors (PFETs), N-channel field effect transistors (NFETs), Metal Oxide Semiconductor Field Effect Transistors (MOSFETs), high voltage transistors, and/or high frequency transistors; other suitable components; and/or combinations thereof. It should also be understood that for additional embodiments of the dual-gate backside sense FET sensor 200, additional components may be added in the dual-gate backside sense FET sensor 200, and some of the components described may be replaced or removed. Commonly owned U.S. patent application publication No. 2013/0200438 and U.S. patent application publication No. 2014/0252421 may find more detail regarding an exemplary fabrication procedure for the dual gate backside sense FET sensor 200.

Fig. 18 is a flow diagram of an embodiment of a method 2100 of fabricating a BioFET device according to one or more aspects of the present disclosure. The method 2100 begins at block 2102, where a substrate is provided. The substrate may be a semiconductor substrate (e.g., a wafer). The semiconductor substrate may be a silicon substrate. Alternatively, the substrate may comprise other elemental semiconductors, such as germanium; a compound semiconductor including silicon carbide, gallium arsenide, gallium phosphide, indium arsenide, and/or indium antimonide; an alloy semiconductor including SiGe, GaAsP, AlInAs, AlGaAs, GaInAs, GaInP and/or GaInAsP; or a combination thereof. In one embodiment, the substrate is a semiconductor-on-insulator (SOI) substrate. The SOI substrate may include a Buried Oxide (BOX) layer formed by a process such as by separation by implanted oxygen (SIMOX) and/or other suitable processes. The substrate may include doped regions, such as p-wells and n-wells.

The method 2100 then proceeds to block 2104, where a Field Effect Transistor (FET) is formed on the substrate. The FET may include a gate structure, a source region, a drain region, and a channel region interposed between the source region and the drain region. Source, drain and/or channel regions may be formed on an active region of a semiconductor substrate. The FET may be an n-type FET (nFET) or a p-type FET (pFET). For example, the source/drain regions may include n-type dopants or p-type dopants depending on the FET configuration. The gate structure may include a gate dielectric layer, a gate electrode layer, and/or other suitable layers. In one embodiment, the gate electrode is polysilicon. Other exemplary gate electrodes include metal gate electrodes comprising materials such as Cu, W, Ti, Ta, Cr, Pt, Ag, Au, and the like; suitable metal compounds such as TiN, TaN, NiSi, CoSi; combinations thereof; and/or other suitable conductive materials. In one embodiment, the gate dielectric is silicon oxide. Other exemplary gate dielectrics include silicon nitride, silicon oxynitride, dielectrics with a high dielectric constant (high-k), and/or combinations thereof.

The method 2100 then proceeds to block 2106, where an opening is formed in the backside of the substrate. The opening may include a trench formed in one or more layers on the backside of the substrate including the FET device. The opening may expose the gate and a region under the body structure (e.g., adjacent to a channel of the FET). In one embodiment, the opening exposes the gate and the active region (e.g., silicon active region) under the active/channel region of the FET device. The openings may be formed using a suitable photolithography process to provide a pattern on the substrate and an etching process to remove material from the backside until the body structure of the FET device is exposed. The etching process may include wet etching, dry etching, plasma etching, and/or other suitable processes.

Method 2100 then proceeds to block 2108, where an interface layer is formed in the opening. An interfacial layer may be formed on the exposed active region under the gate structure of the FET. The interface layer may be compatible (e.g., friendly) with biomolecule or bio-entity binding. For example, the interface layer may provide a binding interface for a biomolecule or biological entity. The interfacial layer may include dielectric materials, conductive materialsAnd/or other suitable materials for retaining the receptor. Exemplary interface materials include high-k dielectric films, metals, metal oxides, dielectrics, and/or other suitable materials. As another example, an exemplary interface material includes HfO₂、Ta₂O₅Pt, Au, W, Ti, Al, Cu, oxides of these metals, SiO₂、Si₃N₄、Al₂O₃、TiO₂、TiN、SnO、SnO₂、SrTiO₃、ZrO₂、La₂O₃(ii) a And/or other suitable materials. The interfacial layer may be formed using a CMOS process such as Physical Vapor Deposition (PVD) (sputtering), Chemical Vapor Deposition (CVD), Plasma Enhanced Chemical Vapor Deposition (PECVD), Atmospheric Pressure Chemical Vapor Deposition (APCVD)). Low pressure cvd (lpcvd), high density plasma cvd (hdpcvd), or Atomic Layer Deposition (ALD). In an embodiment, the interface layer comprises a plurality of layers.

The method 2100 then proceeds to block 2110 where a receptor, such as an enzyme, an antibody, a ligand, a peptide, a nucleotide, an organ cell, an organism, or a tissue fragment, is placed on the interface layer for detection of the target biomolecule.

Referring to fig. 3, a schematic diagram of an exemplary addressable array 300 of FET sensors 304 connected to bit lines 306 and word lines 308 is shown. It should be noted that the terms bit line and word line are used herein to indicate an analogy to the structure of the array in the memory device, however, it is not meant to indicate that a memory device or memory array must be included in the array. The addressable array 300 may have similar characteristics as employed in other semiconductor devices such as Dynamic Random Access Memory (DRAM) arrays. For example, the dual gate backside sense FET sensor 200 described above with reference to fig. 2 can be formed at locations where capacitors exist in a DRAM array. The schematic diagram 300 is merely exemplary, and it can be appreciated that other configurations are possible.

The FET sensors 304 are each substantially similar to the dual gate backside sense FET sensor 200. The FET 302 is configured to provide a connection between a drain terminal of the FET sensor 304 and a bit line 306. In this manner, the FET 302 is analogous to an access transistor in a DRAM array. In this exemplary embodiment, the FET sensor 304 is a dual gate backside sense FET sensor and includes: a sense gate provided by an acceptor material disposed on a dielectric layer over a FET active region disposed at a reaction site; and a control gate provided by a gate electrode (e.g., polysilicon) disposed on a dielectric layer over the FET active region.

The schematic diagram 300 illustrates the formation of an array that may be advantageous for detecting small signal changes provided by the smallest biomolecules or biological entities introduced to the FET sensor 304. The array format using bit lines 306 and word lines 308 allows for a reduction in the number of input/output pads. An amplifier may be used to enhance signal strength to improve the detection capability of a device having the circuit arrangement of diagram 300. In an embodiment, when a particular word line 308 and bit line 306 are set, the corresponding access transistor 302 will turn on (e.g., like a switch). When the gate of an associated FET sensor 304 (e.g., such as the back-side gate 222 of the dual-gate back-side sense FET sensor 200) has a charge that is affected by the presence of a biomolecule, the FET sensor 304 will pass electrons and induce a field-effect charge of the device, thereby modulating the current (e.g., I |)_ds). Electric current (e.g. I)_ds) Or threshold voltage (V)_t) Can be used to indicate detection of a relevant biomolecule or biological entity. Thus, the device with schematic diagram 300 may enable biosensor applications, including applications with differential sensing, for improved sensitivity.

Referring to FIG. 4, an exemplary layout 400 is presented. The exemplary layout 400 includes an access transistor 302 and a FET sensor 304 configured as an array 401 of individually addressable pixels 402. The array 401 may include any number of pixels 402. For example, the array 401 may include 128 x 128 pixels. Other arrangements may include 256 by 256 pixels or non-rectangular arrays such as 128 by 256 pixels.

Each pixel 402 includes: an access transistor 302 and a dual gate backside sense FET sensor 304; and other components, which may include one or more heaters 408 and temperature sensors 410. In this example, access transistor 302 is an n-channel FET. The n-channel FET 412 may also serve as an access transistor for the temperature sensor 410. In this illustrative example, the gates of FETs 302 and 412 are commonly connected, although this is not required. Each pixel 402 (and its associated components) may be individually addressed using a column decoder 404 and a row decoder 406. In one example, each pixel 402 has dimensions of about 10 microns by about 10 microns. In another example, each pixel 402 has dimensions of about 5 microns by about 5 microns, or has dimensions of about 2 microns by about 2 microns.

Column decoder 406 and row decoder 404 can be used to determine the ON/OFF (ON/OFF) state of n- channel FETs 302 and 412. Turning on the n-channel FET 302 provides current to the S/D region of the dual-gate backside sense FET sensor 304. When these devices are turned on, the current I_dsFlows through the FET sensor 304, and can measure the current I_ds。

The heater 408 may be used to locally increase the temperature around the dual gate backside sense FET sensor 304. Heater 408 may be constructed using any known technique, such as forming a metal pattern having a high current therethrough. The heater 408 may also be a thermoelectric heater/cooler, such as a Peltier device. Heater 408 may be used during a particular biological test, such as denaturing DNA or RNA, or providing a more desirable binding environment for a particular biomolecule. The temperature sensor 410 may be used to measure the local temperature around the dual gate backside sense FET sensor 304. In one embodiment, a control loop may be created to control temperature using heater 408 and receive feedback from temperature sensor 410. In another embodiment, the heater 408 may be a thermoelectric heater/cooler that allows for localized active cooling of components within the pixel 402.

Referring to fig. 5, a cross-sectional view of an exemplary dual gate backside sense FET sensor 500 is provided. The dual-gate backside sense FET sensor 500 is one embodiment of the dual-gate backside sense FET sensor 200, and therefore the previously described elements of fig. 2 are labeled with the element symbols of fig. 2, and their description is not repeated here. The dual gate backside sense FET sensor 500 includes a gate 202, a source region 204, a drain region 206, and a channel region 208, wherein the source region 204 and the drain region 206 are formed within a substrate 214. Gate 202, source region 204, drain region 206, and channel region 208 form a FET. It should be noted that the various components of fig. 5 are not intended to be drawn to scale and are exaggerated for visual convenience, as will be appreciated by those skilled in the relevant art.

In an exemplary embodiment, the dual gate backside sense FET sensor 500 is connected to various metal interconnect layers 502, the metal interconnect layers 502 forming electrical connections with various doped regions and other devices formed within the substrate 214. The metal interconnect layer 502 may be fabricated using fabrication processes well known to those skilled in the relevant art.

The dual-gate backside FET sensor 500 may include a body region 504 that is separated from the source region 204 and the drain region 206. Body region 504 may be used to bias the carrier concentration in active region 208 between source region 204 and drain region 206. Accordingly, a negative voltage bias may be applied to the body region 504 to improve the sensitivity of the dual gate backside FET sensor 500. In one embodiment, body region 504 is electrically connected to source region 204. In another embodiment, the body region 504 is electrically grounded.

The dual gate backside FET sensor 500 may be connected to additional circuitry 506 fabricated within the substrate 214. The circuit 506 may include any number of MOSFET devices, resistors, capacitors, or inductors to form a circuit that assists in operating the dual gate backside sense FET sensor 500. For example, column decoder 406 and row decoder 404 may be formed in circuitry 506. The circuit 506 may include any amplifier, analog-to-digital converter (ADC), digital-to-analog converter (DAC), voltage generator, logic circuit, and DRAM memory, to name a few examples. All or some of the components of the additional circuitry 506 may be integrated in the same substrate 214 as the dual gate backside FET sensor 500. It should be understood that multiple FET sensors, each substantially similar to the dual-gate backside FET sensor 500, may be integrated onto the substrate 214 and connected to additional circuitry 506. In another example, all or some of the components of the additional circuitry 506 are provided on another semiconductor substrate separate from the substrate 214. In yet another example, some components of the additional circuitry 506 are integrated in the same substrate 214 as the dual gate backside FET sensor 500, and some components of the additional circuitry 506 are provided on another semiconductor substrate separate from the substrate 214.

Still referring to FIG. 5In an illustrative example, the dual gate backside sense FET sensor 500 includes an interface layer 508 deposited over the isolation layer 210 and within the opening over the channel region 208. In one embodiment, the interfacial layer 508 has a thickness of between about

And the combination

To the thickness of (d) in between. Interfacial layer 508 may be, for example, hafnium silicate, hafnium oxide, zirconium oxide, aluminum oxide, tantalum pentoxide, hafnium oxide-aluminum oxide (HfO)₂-Al₂O₃) Alloys, or any combination thereof. As will be discussed in more detail below in the section directed to biosensing, interface layer 508 may serve as a support to attach capture reagents.

An exemplary operation of the dual gate backside FET sensor 500 for use as a pH sensor will now be described. Briefly, the fluid gate 510 is used to provide electrical contact to the "second gate" of the dual gate backside sense FET sensor. A solution 512 having a given pH is provided over the reaction sites of the dual gate backside sense FET sensor 500, and a fluid gate 510 is placed within the solution 512. The pH of the solution is generally related to the hydrogen ions [ H ] in the solution⁺]Is concerned with. The accumulation of ions near the surface of interface layer 508 over channel region 208 will affect the formation of an inversion layer within channel region 208, which channel region 208 forms a conductive path between source region 204 and drain region 206. This can be measured by a change in the conductivity of the FET sensor. In one embodiment, during sensing, fluid gate 510 serves as the gate of the transistor, while gate 202 remains floating. In another embodiment, during sensing, fluid gate 510 serves as the gate of a transistor, while gate 202 is biased at a given voltage. For example, gate 202 may sweep fluid gate 510 between a range of voltages, biased at a voltage between-2V and 2V depending on the application. In another embodiment, during sensing, fluid gate 510 is biased at a given voltage (or ground), while gate 202 serves as the gate of the transistor (e.g., its voltage is swept through a range of voltages). Fluid grid 510May be formed of platinum or may be formed of any other commonly used material for reference electrodes in electrochemical analysis. The most common reference electrode is an Ag/AgCl electrode with a stable voltage value of about 0.230V.

Fig. 6A shows ions in solution bound to the surface of interface layer 508. The topmost atomic layer of interfacial layer 508 is depicted as variously floating [ O ]^-]、[OH]And [ OH₂ ⁺]A key. When ions accumulate on the surface, the total surface charge affects the threshold voltage of the transistor. As used herein, the threshold voltage is the minimum potential between the gate and source of the FET sensor required to form a conductive path of minority carriers between the source and drain of the FET sensor. The total charge is also directly related to the pH of the solution, since a higher accumulation of positive charges indicates a low pH, and a higher accumulation of negative charges indicates a high pH. Fig. 6B shows the change in threshold voltage due to different pH values in an n-channel FET sensor. As can be seen from the graph, an increase in the threshold voltage of 59mV roughly indicates an increase in the pH of the solution of 1. In other words, when measuring the voltage required to turn on the transistor, one pH change results in an overall surface equivalent charge of 59 mV.

Chip package

Referring to fig. 7, an exemplary plan view of a semiconductor chip 702 is shown. Chip 702 includes sensor array 704, optional reference electrode 706, analog circuitry 708, and I/O pads 716. Chip 702 may be silicon, gallium arsenide, or indium phosphide, to name a few. Chip 702 may have dimensions of about 3mm by about 2.5 mm.

Sensor array 704 represents an array of dual gate backside sense FET sensors, such as those shown above in fig. 2 and 5. For example, in fig. 4, the array may be arranged as a row-column matrix of pixels as shown. Each FET sensor in sensor array 704 can be functionalized with the same or different capture reagents to perform biosensing of each analyte.

The reference electrode 706 may be patterned on the same chip 702 that includes the sensor array 704. Reference electrode 706 can be substantially aligned with sensor array 704 along the X or Y direction such that a fluid channel can be placed over both sensor array 704 and reference electrode 706. In another embodiment, reference electrode 706 is provided elsewhere than on chip 702.

The reference electrode 706 may comprise any material having a relatively stable potential. Exemplary reference electrode materials include platinum or Ag/AgCl. The described fabrication of Ag/AgCl electrodes on a substrate surface is well known in the art, for example by Moschou et al in 2015 "sensor" volume 15(8) page 18102-18113 "surface and electrical characterization of Ag/AgCl pseudo-reference electrodes fabricated using commercially available PCB technology".

Analog circuitry 708 may include circuitry related to the operation of sensor array 704. Thus, analog circuitry 708 may be configured to provide signals to and measure signals from sensor array 704 while interfacing with various I/O pads 716. In one embodiment, analog circuitry 708 includes a Serial Peripheral Interface (SPI)712 and a sensor array circuit 714. In this embodiment, the spacing between sensor array 704 and sensor array circuitry 714 is not less than about 135 microns.

SPI 712 may be a serial interface circuit to facilitate data transfer between sensor array circuit 714 and the analyzer unit, described in more detail below. The general operation of an SPI will be well understood by those skilled in the relevant art. The sensor array circuit 714 may include any number of reference voltage generators, operational amplifiers, low pass filters, ADCs, and DACs to provide signals to the sensor array 704 and to receive signals from the sensor array 704.

In one example, the bias reference voltage may be generated using sensor array circuitry 714 to provide a negative bias voltage of about-0.24 volts to the body region of a given FET sensor or group of FET sensors in sensor array 704. When sensing is implemented, an adjustable voltage may also be provided to the fluid gate of a given FET sensor or group of FET sensors in sensor array 704.

When measuring signals (e.g., Ids) received from a given FET sensor or group of FET sensors in sensor array 704, sensor array circuitry 714 may receive the measured signals and transmit them through a transimpedance amplifier, i.e., a current-to-voltage converter, followed by one or more additional amplification stages, a low pass filter, and finally an ADC, before outputting the resulting signals to I/O pad 716. The noise in the measurement signal may also be reduced by subtracting the background AC signal from the measurement signal before amplifying the measurement signal. The temperature signal (received from one or more temperature sensors in the sensor array 704) may also be amplified, filtered, and transmitted through an ADC before being output to the I/O pad 716.

In various embodiments, a plurality of I/O pads 716 may be patterned along the periphery of chip 702. More I/O pads may be provided than the actual inputs and outputs used by the various components of chip 702. In one embodiment, wire bonding techniques may be used to connect individual I/O pads 716 to another substrate or package to which chip 702 is bonded. In one particular embodiment, 32I/O pads may be patterned around the periphery of chip 702. The dimensions of a given I/O pad 716 may be about 80 microns by about 70 microns, and the spacing between I/O pads 716 may be about 150 microns. The spacing between sensor array 704 and the nearest I/O pad 716 may be no shorter than about 400 microns, while the spacing between I/O pad 716 and the outermost edge of chip 702 may be no shorter than about 177.5 microns.

Referring to fig. 8, an exemplary packaging scheme for chip 702 is shown. Chip 702 having I/O pads 716 is bonded to carrier layer 802. Carrier layer 802 may be another semiconductor substrate such as a silicon substrate. In another example, carrier layer 802 is an insulator such as a hard plastic material. Chip 702 may be bonded to carrier layer 802 using any known bonding technique, such as by using solder or adhesive.

In one embodiment, carrier layer 802 includes a plurality of through-holes filled with conductive material 804. The conductive material 804 may be any metal such as, but not limited to, tin, copper, aluminum, gold, or any alloy thereof. Conductive material 804 may include solder bumps or balls located at bottom surface 805 of carrier layer 802. The solder may extend beyond surface 805.

According to an embodiment, the chip package further comprises a first insulating layer 806 abutting the side faces of the chip 702. First insulating layer 806 may also be a plastic material or resin that fills the area around chip 702 and may help secure chip 702 in place. In an exemplary embodiment, the first insulating layer 806 includes through vias that are also filled with conductive plugs 808. Conductive plug 808 may be the same material as conductive material 804. Conductive plugs 808 are substantially aligned over corresponding regions of conductive material 804 such that an ohmic contact is formed between conductive plugs 808 and conductive material 804.

Once chip 702 has been secured to carrier layer 802 with first insulating layer 806 around it, electrical connections 812 may be formed between I/O pads 716 and conductive plugs 808. One skilled in the relevant art will appreciate that electrical connections 812 may be formed using wire bonding techniques. In another example, electrical connections 812 are formed using a photolithographic patterning technique that patterns conductive traces to electrically connect I/O pads 716 with corresponding conductive plugs 808. Once the electrical connections 812 are formed, a second insulating layer 810 may be deposited to protect the electrical connections 812 from the environment. The second insulating layer 810 may be the same material as the first insulating layer 806. The second insulating layer 810 may be a resin material that flows around the electrical connections 812 and then hardens to form a protective shell. An opening 814 is formed within second insulating layer 810 to create a via towards the sensor array present on chip 702. In embodiments where the reference electrode is also patterned on chip 702, then opening 814 will create a path towards the sensor array and the reference electrode.

The final chip package 816 includes a chip 702 bonded to carrier layer 802 and electrically connected to various conductive pads or metal pads located on a bottom surface 805 of carrier layer 802. Chip 702 is also protected from the environment by first insulating layer 806 and second insulating layer 810. Chip package 816 may be more easily handled and connected to larger substrates such as Printed Circuit Boards (PCBs). In some embodiments, chip package 816 may be connected to one or more heat sinks to provide a more efficient heat dissipation path from chip 702 into the ambient air or into the substrate to which chip package 816 is attached. In other embodiments, chip package 816 may be connected to a Peltier device to provide thermoelectric heating and/or cooling.

Referring to the illustrative embodiment of fig. 9, a chip package 816 is bonded to a substrate 902. Substrate 902 may be a PCB that includes conductive contact pads to make electrical contact with solder or conductive pads on the bottom surface of carrier layer 802. Flip chip bonding techniques may be implemented to bond the chip package 816 to the surface of the substrate 902. Briefly, solder or conductive pads along the bottom surface of carrier layer 802 are aligned with corresponding conductive pads patterned on substrate 902 and bonded together to physically attach chip package 816 to substrate 902 and to electrically connect I/O pads from chip 702 to conductive traces present on substrate 902. The conductive traces on the substrate 902 terminate in edge connections 908.

One or more edge connectors 908 may provide electrical connections to chip 702. One or more other edge connections 908 can provide electrical connections to a reference electrode 906 patterned on the surface of the substrate 902. The use of reference electrode 906 may eliminate the need to provide a reference electrode on chip 702. Each of the one or more edge connectors 908 may be patterned using a metal such as, but not limited to, copper, gold, or aluminum. Reference electrode 906 can be fabricated using the same techniques discussed above for reference electrode 706 on chip 702.

Exemplary chip packages 816 may have dimensions between about 1 and 2 centimeters by 1 and 2 centimeters or less, while substrate 902 may have dimensions between 3 and 4 centimeters by 3 and 4 centimeters or less.

Opening 814 is shown above chip 702, exposing at least the sensor array of chip 702. In an exemplary embodiment, the opening 814 is substantially aligned with the reference electrode 906 in the X or Y direction such that the fluid channel can be placed over both the opening 814 and the reference electrode 906.

Fluid design

Referring to fig. 10, a schematic diagram of an exemplary fluidic cartridge 1000 is provided. The schematic shows a top-down view of the cassette 1000, and it should be noted that not all of the elements shown are on the same horizontal plane. Furthermore, the specific dimensions and proportions of the various fluid channels are purposefully not drawn to scale in order to improve visualization. The cartridge 1000 includes a housing 1002. Housing 1002 may be formed from any plastic material, such as Polymethylmethacrylate (PMMA), to name a few examples, using injection molding, casting, or 3-D printing techniques. Housing 1002 may be formed from more than one section that are joined together mechanically or through the use of an adhesive. In one embodiment, the various fluid channels and chambers may be molded within one or more components of housing 1002. In another embodiment, the individual fluid channels and chambers are formed from different molded polymer materials, such as Polydimethylsiloxane (PDMS). The overall dimensions of housing 1002 may be between about 4 centimeters to about 7 centimeters by about 4 centimeters to about 7 centimeters. As technology advances, housing 1002 may become smaller. In one embodiment, a substrate 902 having a packaged chip 802 is disposed within a housing 1002. In one example, only a portion of substrate 902 is encapsulated within housing 1002, while edge connector 908 is exposed outside of housing 1002.

The fluid design of the example housing 1002 includes at least a first channel 1004, a second channel 1006, and a third channel 1008. The first and second channels 1004 and 1006 each include a corresponding fluid inlet 1010a and 1010b, respectively. The fluid inlet provides a region for injecting fluid into the cartridge 1000 from the outside of the cartridge 1000. The fluid inlet also provides a region for discharging fluid from the cassette 1000 to the outside of the cassette 1000. The third channel 1008 may be aligned over the packaged chip 802 bonded to the substrate 902. In one embodiment, the opening 814 over the sensor array is located substantially within the third channel 1008. According to an embodiment, a reference electrode 906 patterned on the substrate 902 is also aligned within the third channel 1008.

The first channel 1004, the second channel 1006, and the third channel 1008 may each have a channel width between about 1 millimeter and 3 millimeters. The channel height may be about 1 mm. In another embodiment, one or more of the first channel 1004, the second channel 1006, and the third channel 1008 is a microfluidic channel having width and height dimensions less than 1 mm. The first channel 1004, the second channel 1006, and the third channel 1008 may each have a rectangular, square, or semi-circular cross-section.

In some embodiments, one or more of the first channel 1004 and the second channel 1006 are connected to a third channel 1008. In this manner, fluid flowing through the first channel 1004 will eventually flow through the third channel 1008, and similarly fluid flowing through the second channel 1006 will eventually flow through the third channel 1008. In some embodiments, the third channel 1008 eventually flows into a waste chamber 1016 that collects all of the fluid flowing through the cassette 1000. The waste chamber 1016 may include a vent to atmosphere (not shown) to avoid back pressure build-up within the fluid system.

In some embodiments, inlets 1010a and 1010b include plugs 1012a and 1012b, respectively. The plugs 1012a/1012b may be soft, flexible material that fits tightly into the inlets 1010a/1010b to seal the inlets from any fluid leakage. Plugs 1012a/1012b may be a polymer material such as Polytetrafluoroethylene (PTFE) or cork. The plugs 1012a/1012b may seal the inlets 1010a/1010b while allowing capillaries to pass through the plugs 1012a/1012b without damaging the fluid seal. The capillary tube may be a needle tube such as a syringe needle. The capillary tube may comprise a hard rigid material such as metal or hard plastic. In discussing the connection of the cartridge 1000 to the analyzer, the connection of the capillary to the cartridge 1000 will be described in more detail later.

The cartridge 1000 includes a sample inlet 1014 arranged to introduce a sample into either the first channel 1004 (as shown in fig. 10) or the second channel 1006. In one example, a blood sample can be placed into the fluidic system through the sample inlet 1014. Once the sample has been introduced, the sample inlet 1014 can be sealed using a cap or any other similar structure to provide a leak-proof seal around the sample inlet 1014. In the channel arrangement shown in fig. 10, fluid flowing through the first channel 1004 from the inlet 1010a will mix with the sample introduced through the sample inlet 1014, and the mixture will flow over the opening 814 in the third channel 1008 and the reference electrode 906. Once the sample has been transferred to the Sensor array exposed by the opening 814, interactions between biomolecules may occur and the FET Sensor may be used to detect the presence or measure the concentration of a particular analyte in the sample. Pressure driven flow may be used to move fluid along and between the various channels, to name a few. Pressure may be caused by a syringe forcing liquid or air through the cartridge 1000, or by pressurized air pushing on the liquid. Other examples of techniques for delivering liquids through cassette 1000 include electrowetting or the use of peristaltic pumps on a chip. In some embodiments, fluid mixing may be performed within cartridge 1000 using any of the various on-chip mixing methods known in the art. The dimensions of the fluid channel of the cartridge 1000 may be large enough that some fluid mixing occurs due to turbulence of the liquid as it moves through the channel. It should be understood that the location of the sample inlet 1014 may vary. For example, sample inlet 1014 may be located directly above opening 814 such that a sample introduced into sample inlet 1014 is also introduced above the sensor array exposed through opening 814.

Once substrate 902 has been integrated into housing 1002, the sensor array accessed through opening 814 can be functionalized with various capture reagents, according to embodiments. The process may involve flowing a liquid buffer including a capture reagent through the third channel 1008, thereby allowing an opportunity for the capture reagent to bind to individual FET sensors in the sensor array. In another example, when sample inlet 1014 is positioned over opening 814, a capture reagent is positioned directly over opening 814. After the capture reagent has been immobilized, the sample inlet 1014 can be sealed, thereby allowing the cartridge 1000 to be stored until ready for the biosensing test to be performed. The capture reagent may remain in its original buffer solution, or a new buffer solution may be introduced to preserve the capture reagent while the cassette 1000 waits for testing. Provided herein are various capture reagents and examples of performing assays using the capture reagents.

Referring to fig. 11, another design of the various fluid passage channels for the cartridge 1000 is shown. In this design, a first channel 1104 having a first inlet 1102a and a second channel 1106 having an inlet 1102b converge at a region having a sample inlet 1110. A third channel 1108 having an opening 814 aligned therein is connected to the first channel 1104 and the second channel 1106 at the sample inlet 1110. Opening 814 provides a path down to the chip to expose at least the sensor array on the chip to the fluid in third channel 1108. Fluid flowing from the first channel 1104 or the second channel 1106 through the third channel 1108 is ultimately collected in the waste chamber 1112. The fluid may be directed toward the waste chamber 1112 based on the geometry of the individual channels or by closing particular channels using a valve. Sample inlet 1110 may also be located above opening 814.

One or more of the first channel 1104, the second channel 1106, and the third channel 1108 may include a bubble well 1114. Bubble trap 1114 may represent an area of fluid channel with an abruptly larger cross-section (or higher "ceiling") so that any air present in the solution may rise into the additional space created at bubble trap 1114. One skilled in the relevant art will appreciate that other bubble trap designs may be used. Removing bubbles from the solution before it reaches the sensor array below the opening 814 is important to ensure accurate sensing results.

Referring to fig. 12, a cartridge 1000 is shown connected to an analyzer 1200 for performing biosensing. The cartridge 1000 may be brought into physical contact with the analyzer 1200 by, for example, pressing the cartridge 1000 toward a receiving port of the analyzer 1200. The receiving port of the analyzer 1200 may include electrical pads for making ohmic contact with some or all of the edge connectors 908. The edge of substrate 902 may fit snugly into a receiving port of analyzer 1200 such that edge connector 908 abuts (press against) a corresponding conductive pad of analyzer 1200. In addition, other methods of assembling the cartridge 1000 and the analyzer 1200 include clipping them together and inserting one into the other. The analyzer 1200 may be small enough to be portable and may fit into an adult human palm.

In some embodiments, analyzer 1200 includes at least a first syringe 1202a and a second syringe 1202 b. The first and second syringes 1202a, 1202b may each include a buffer or other fluid used during operation of the cartridge 1000. The syringes 1202a/1202b each include a needle 1204a/1204b aligned to extend into a space away from the remainder of the analyzer 1200. In some embodiments, the pins 1204a/1204b may be aligned such that pressing the cartridge 1000 toward a receiving port of the analyzer 1200 may cause the pins 1204a/1204b to pass through the corresponding plugs 1012a/1012b and into the inlets 1010a/1010 b. In this embodiment, the pins 1204a/1204b are one example of capillaries passing through corresponding plugs 1012a/1012 b. Thus, a leak-proof seal is created to transfer the solution from each syringe 1202a/1202b into the corresponding inlet 1010a/1010b of cassette 1000. It should be understood that although the description only describes two syringes aligned with two input ports, any number of syringes and fluid input ports may be used, including examples where only one syringe is used in connection with a single inlet port. Each syringe 1202a/1202b can be pre-filled with a solution for a respective test. In another embodiment, each syringe 1202a/1202b can be easily removed and replaced with a different syringe by the user.

Each syringe 1202a/1202b may have a piston associated therewith controlled by a corresponding actuator 1206a/1206 b. Examples of actuators 1206a/1206b include stepper motors or induction motors. The speed at which the actuators 1206a/1206b depress the pistons of the syringes 1202a/1202b will directly affect the flow rate of the solution within the fluid channels of the cartridge 1000. The actuators 1206a/1206b may be controlled by motor control modules 1208a/1208 b. One skilled in the relevant art will appreciate that the motor control modules 1208a/1208b include the circuitry required to generate the voltages used to control the speed and operation of the actuators 1206a/1206 b.

All electrical connections made to the edge connector 908 of the cassette 1000 may be routed to the sensing electronics 1210. The sensing electronics 1210 can include any number of discrete circuits, integrated circuits, and discrete analog circuit components designed to provide and receive many different electrical signals between the sensing electronics 1210 and the edge connector 908. For example, sensing electronics 1210 may be configured to provide power, ground, and clock signals to edge connections 908, which may subsequently be used to power and operate the sensor array and other electronics on chip 702. The sensing electronics 1210 can also provide various voltage bias levels for activating the gates of particular FET sensors within the sensor array. Sensing electronics 1210 may receive a signal representing the drain current measured from a particular FET sensor, as well as a signal representing the output from a temperature sensor on chip 702. Sensing electronics 1210 may store this received data in memory, or may use the received data to change the voltage bias level, or change the heat generated by the heater on chip 702. In general, the sensing electronics 1210 control all signaling associated with biosensing performed by the sensor array of the cartridge 1000.

In some embodiments, analyzer 1200 also includes a processor 1212 that controls the functions and timing of each other module of analyzer 1200, such as motor control modules 1208a/1208b and sensing electronics 1210. Processor 1212 may be any type of Central Processing Unit (CPU) or microcontroller and may be programmed by a user to perform specific functions related to the operation of analyzer 1200. The processor 1212 may be configured to analyze the signals received from the sensing electronics 1210 to determine a concentration level of a given analyte from the sample in the cartridge 1000. Data associated with the determined concentration levels may be stored in a memory of analyzer 1200. In another embodiment, the sensing electronics 1210 determine a concentration level of a given analyte from a sample in the cartridge 1000, and are further configured to store data related to the determined concentration level in a memory of the analyzer 1200.

In some embodiments, analyzer 1200 includes a communication module 1214 designed to communicate data with an external processing device. The processor 1212 can be in electrical communication with the communication module 1214 to control data transfer. The communication may be wired or wireless. Examples of wired communication include data transmission over a network cable or a Universal Serial Bus (USB) cable. The wireless communication may include wireless RF transmission, bluetooth, WiFi, 3G or 4G. The communication module 1214 may also be designed to receive data from an external processing device. For example, programs for how the various components of the analyzer 1200 operate can be sent to the communication module 1214 and executed by the processor 1212. The communication module 1214 may include any number of well-known hardware elements to facilitate analog and/or digital data transmission and reception.

After the biosensing test has been performed, the cartridge 1000 may be removed from the analyzer 1200 and discarded. In addition, the syringes 1202a/1202b can be removed from the analyzer 1200 and discarded. Thus, all reagents remain included in the cartridge 1000 or syringes 1202a/1202b and no contamination of any other portion of the analyzer 1200 occurs. In this manner, a single analyzer 1200 may be reused to test any number of additional cartridges, where each cartridge may be individually functionalized with different capture reagents to perform different biosensing tests.

In another embodiment, the syringes 1202a/1202b are integrated onto the cartridge 1000, and the connection between the cartridge 1000 and the analyzer 1200 aligns the associated pistons of the syringes 1202a/1202b with the actuators 1206a/1206b on the analyzer 1200. In this embodiment, analyzer 1200 is completely devoid of any reagent carrying containers.

In another embodiment, the cartridge 1000 includes one or more capillaries that pass through corresponding plugs 1012a/1012 b. In this embodiment, when a connection occurs between the cartridge 1000 and the analyzer 1200, the capillary tube is fluidly connected to the remaining syringes 1202a/1202b in the analyzer 1200. After the biosensing test has been performed, the cartridge 1000 and its capillaries can be removed from the analyzer 1200 and discarded.

Referring to fig. 13, an exemplary method 1300 is shown. The method 1300 may be performed by the analyzer 1200 after the cartridge 1000 has been connected to the analyzer 1200. Other operations related to fluid processing and electrical measurements not shown in method 1300 may be performed before, during, or after the illustrated operations of method 1300. The operations of method 1300 are performed in an order different than the order shown. In an embodiment, method 1300 is performed after the capture reagent has been immobilized within cartridge 1000.

At block 1302, a first solution flows through a first channel of a cartridge. The first solution may enter the cartridge through an inlet connected to the first channel. The first solution may be provided by a syringe having a needle passing through a plug disposed at an inlet of the first channel. The first solution may include a buffer solution to provide a stable pH environment.

At block 1304, dual-gate backside sense FET sensors of the sensor array are calibrated in a first solution. Calibration may be performed to measure noise or background signals of individual FET sensors. The measurement can be stored and later subtracted from the measurement signal when detecting the biomolecule to try and reduce noise and obtain a clearer detection signal. The first solution must be present over the sensor array and the reference electrode patterned in the main detection channel to perform the calibration. In some embodiments, the first solution does not flow during the calibration measurement. In some embodiments, the calibration measurement represents a reference threshold voltage of the FET sensor.

At block 1306, a sample is input into the fluidic network of the cartridge through the sample inlet. The sample may be any liquid sample including a blood sample. In some embodiments, the sample is a semi-solid sample that decomposes in solution. After the sample has been input through the sample inlet, the sample inlet may be sealed by using a cap or other similar structure.

At block 1308, a second solution flows through a second channel of the cartridge. The second solution may be the same solution as the first solution. The second solution may intersect the path of the sample input to the fluidic system at block 1306 and mix with the sample. The mixture of sample and second solution may then flow through the second channel and into the primary detection channel where the sensor array is located. The second solution may be a buffer solution. In one example, the second solution is a decomposed buffer solution. A pressure-driven flow may be used to move the second solution along and between the respective channels. Pressure may be caused by a syringe forcing liquid or air through the cartridge, or by pressurized air pushing against the second solution, to name a few examples. Other examples of techniques for delivering the second liquid through the cartridge include electrowetting or the use of peristaltic pumps on a chip.

At block 1310, biomolecules present within the sample are cultured over the sensor array. The incubation may be for any given time, for example, between 30 seconds and 10 minutes. During incubation, the sample mixed with the second solution may not flow, or may flow at a very slow flow rate. The flow rate can be designed so that fresh solution appears over the sensor array over time, but the flow is not so strong as to damage the capture reagent or render the binding reaction impossible.

At block 1312, after the incubation time has expired, the third solution flows through the first channel of the cartridge and through the primary detection channel to push substantially all of the sample mixed with the second solution into the waste chamber. A third solution may be injected through the main detection channel for a given period of time to ensure that the sample has cleared the main detection channel. Ideally, the third solution used in block 1312 is the same solution as the first solution. In another embodiment, the third solution is different from the first solution. The third solution may be a buffer solution.

At block 1314, the output of the sensor array is measured to determine if any binding reactions have occurred. The sensor output may be a drain current measured from one or more dual gate backside sense FET sensors in the sensor array. The measured drain current may be compared to the drain current measured during calibration of the same sensor in block 1304. If the threshold voltage (e.g., approximately corresponding to the voltage required to turn on the FET and cause drain current to flow) has changed when the sensor is calibrated, it can be determined that a binding reaction has occurred and that the target analyte is present in the sample. The amount and sign of the threshold voltage change may depend on many factors: such as whether the dual gate backside sense FET sensor is an n-channel device or a p-channel device, the type of analyte detected and the amount of positive or negative charge associated with the analyte. In another example, the measured output from the sensor array is the threshold voltage itself, which may be compared to the threshold voltage measured during calibration of the same sensor in block 1304.

Chemical, biological and interfacial

The devices, systems, and methods of the invention described in this application can be used to detect and/or monitor interactions between various entities. These interactions include biological and chemical reactions to detect target analytes in a test sample. By way of example, reactions including physical, chemical, biochemical or biological conversions may be monitored to detect production of intermediates, byproducts, products and combinations thereof. In addition, the devices, systems, and methods of the present invention can be used to detect these reactions in the various assays described herein, including, but not limited to, circulating tumor cell assays for liquid biopsy and chelation assays (chelationassay) to detect the presence of heavy metals and other environmental contaminants. Such assays and reactions can be monitored in a single format or an array format to detect, for example, multiple target analytes.

Biosensing examples with DGBSS FET sensors

Referring to fig. 14, an exemplary biosensing test is conducted using the dual-gate backside sense FET sensor described above. Probe DNA 1404 (an example of a capture reagent) is bonded to the interface layer 508 through linker molecules 1402. The linking molecules 1402 may have reactive chemical groups that bond to portions of the interface layer 508. Examples of linker molecules include thiols. The surface of interface layer 508 may also be exposed to ammonia (NH) by silylation of the surface of interface layer 508 or by exposing the surface of interface layer 508 to NH₃) Plasma to form reactive NH on a surface₂The groups form a linker molecule. As is generally understood by those skilled in the relevant art, the silylation process involves sequentially exposing the surface of the interface layer 508 to different chemicals to establish covalently bound molecules on the surface of the interface layer 508. The probe DNA 1404 represents a single-stranded DNA. According to an embodiment, the linking molecules 1402 are bonded to the interface layer 508 before any of the steps of the method 1300 are performed. The probe DNA 1404 may also be bound to a linker molecule 1402 before performing any of the steps of the method 1300. In another example, probe DNA 1404 is joined to a linker molecule 1402 at block 1302 of method 1300.

According to an embodiment, the dual gate backside sense FET sensor shown in fig. 14 is one FET that would be present within a sensor array on a chip such as chip 702 described above. The tie molecules 1402 may be bonded to the interface layer 508 before dicing the wafer including the chips 702 to separate the chips 702 from the wafer.

The probe DNA 1404 may be immobilized on the interface layer 508 prior to subjecting the FET sensor to the sample 1401. The sample 1401 may include a paired single-stranded DNA sequence 1406 that binds strongly to its paired probe DNA 1404. Additional DNA binding increases the negative charge present on interface layer 508 and is located directly over channel region 208 of the FET sensor.

DNA binding is conceptually shown in fig. 15A. Here, the probe DNA having the nucleic acid sequence TCGA binds to its complementary partner strand having the nucleic acid sequence AGCT. Any unpaired sequence will not hybridize to the probe DNA sequence. The binding of the paired DNA increases the negative charge that accumulates at the interface of the interface layer 508. In the example shown in fig. 15A, the interfacial layer 508 is hafnium oxide.

Fig. 15B shows the threshold voltage shift of the dual gate backside sense FET sensor when the paired DNA is bound to the surface of the interface layer 508. In short, a voltage is applied to the fluid gate 510 until the FET sensor is "on" and current flows between the drain region 206 and the source region 204. When more negative charge is present on interface layer 508 due to complementary DNA binding, a higher voltage is required to form a conduction inversion layer within channel region 208. Thus, according to an embodiment, a higher voltage may be applied to the fluid gate 510 before the FET sensor is turned on and the Ids current flows. This difference in threshold voltage can be measured and used to determine the presence of the DNA sequence of the target pair, as well as its concentration. It will be appreciated that the net positive accumulated charge at the interface layer 508 will result in a decrease in threshold voltage rather than an increase. Additionally, the change in threshold voltage of an n-channel FET will have an opposite sign compared to a p-channel FET.

Referring to fig. 16, another exemplary biosensing test is conducted using a dual gate backside sense FET sensor. Probe antibody 1604 (another example of a capture reagent) is bound to interface layer 508 through linker molecule 1602. The connecting molecules 1602 may have reactive chemical groups that bond to portions of the interface layer 508. A sample solution 1601 can be provided over the probe antibody 1604 to determine whether a paired antigen is present within the sample solution 1601. According to an embodiment, the linking molecules 1602 are bonded to the interface layer 508 before any of the steps of the method 1300 are performed. The probe antibody 1604 may also bind to the linker molecule 1602 prior to performing any of the steps of the method 1300. In another example, probe antibody 1604 is conjugated to binding molecule 1602 at block 1302 of method 1300.

Referring to FIG. 17, the binding process of the partner antigen to the probe antibody 1604 is shown. Here, the paired antigen will bind to the immobilized probe antibody, while the unpaired antigen will not. Similar to the DNA hybridization process described above, the paired antigen will change the accumulated charge present at the interface layer 508. The shift in threshold voltage due to the accumulated charge from the partner antibody bound to the probe antibody is measured in substantially the same manner as has been discussed above with reference to fig. 15B.

In an embodiment, there is provided a fluid cartridge comprising: a substrate including a plurality of contact pads configured to be electrically connected to an analyzer, a semiconductor chip having a sensor array, and a reference electrode; a first fluid channel having a first inlet and connected to a second fluid channel, the second fluid channel aligned such that the sensor array and the reference electrode are disposed within the second fluid channel; a sample inlet for placing a sample within the path of the first or second fluid channel; a first plug disposed at the first inlet and comprising a flexible material configured to be traversed by a capillary tube without leakage of fluid through the first plug.

In an embodiment, the fluid cartridge further comprises a third fluid channel having a second inlet.

In an embodiment, the third fluid channel is connected to the second fluid channel.

In an embodiment, the fluid cartridge further comprises a second plug disposed at the second inlet and comprising a flexible material configured to be passed through by the capillary without leakage of the fluid through the second plug.

In an embodiment, the first and second plugs are configured to align with first and second capillaries connected to the analyzer, and a plurality of contact pads are connected with the analyzer when the fluidic cartridge and the analyzer are in physical contact.

In an embodiment, the first and second capillaries pass through the first and second plugs, respectively, when the fluidic cartridge and the analyzer are in physical contact.

In an embodiment, the substrate is a printed circuit board.

In an embodiment, the fluidic cartridge further comprises a waste chamber connected to the second fluidic channel.

In an embodiment, one or more sensors of the sensor array comprise a plurality of probe molecules configured to bind to target molecules present in the sample.

In an embodiment, the sensor array comprises a dual gate backside sense FET sensor array.

In an embodiment, there is provided a fluid cartridge comprising: a first fluid channel having a first inlet and connected to a second fluid channel, the second fluid channel aligned such that the sensor array and the reference electrode are disposed within the second fluid channel; a sample inlet for placing a sample within the path of the first or second fluid channel; a first plug disposed at the first inlet and comprising a flexible material configured to be traversed by a capillary without leakage of fluid through the first plug, wherein the capillary is connected to an analyzer and the capillary traverses the first plug when the fluidic cartridge is in physical contact with the analyzer.

In an embodiment, the sensor array comprises a dual gate backside sense FET sensor array.

In an embodiment, one or more sensors of the sensor array comprise a plurality of probe molecules configured to bind to target molecules present in the sample.

In embodiments, the plurality of probe molecules comprises one or more of DNA, RNA, and antibodies.

In an embodiment, the fluid cartridge further comprises: having a plurality of contact pads configured to electrically connect with the analyzer, a semiconductor chip having the sensor array, and a reference electrode.

In an embodiment, there is provided an analyzer configured to be connected to a fluidic cartridge, the analyzer comprising:

a syringe arranged such that when the fluid cartridge is physically connected to the analyzer, a needle of the syringe is aligned with a corresponding input port of the fluid cartridge;

an actuator configured to control operation of the injector;

a sensing module configured to send and receive signals to and from the fluidic cartridge via a plurality of conductive pads when the fluidic cartridge is physically connected to the analyzer, wherein the plurality of conductive pads contact a corresponding plurality of conductive pads on the fluidic cartridge; and a processor electrically connected to the sensing module and configured to determine a concentration level of a given analyte from a sample in the fluidic cartridge based on a signal received from the fluidic cartridge.

In an embodiment, the analyzer further comprises an actuator controller configured to control operation of said actuator.

In an embodiment, the processor is also electrically connected to the actuator controller.

In an embodiment, the analyzer further comprises at least one further syringe arranged such that a needle of the at least one further syringe is aligned with a corresponding input port of the fluid cartridge when the fluid cartridge is physically connected to the analyzer.

In an embodiment, the analyzer further comprises a memory configured to store data related to the concentration level of the given analyte determined by the processor.

Final remarks

It is to be understood that the detailed description section, and not the abstract of the disclosure section, is intended to be used to interpret the claims. The abstract of the disclosure may set forth one or more, but not all exemplary embodiments of the invention contemplated by the inventor(s), and is therefore not intended to limit the invention and the associated claims in any way.

It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in the light of the teachings and guidance herein.

The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.

Claims (20)

1. A fluid cartridge, comprising:

a substrate comprising

A plurality of contact pads configured to electrically connect with an analyzer,

a semiconductor chip having a sensor array, and

a reference electrode;

a first fluid channel having a first inlet and extending from the first inlet to a second fluid channel, the second fluid channel aligned such that the sensor array and the reference electrode are disposed within the second fluid channel;

a third fluid channel having a second inlet extending from the second inlet to the second fluid channel, wherein the first and second inlets are both for injecting fluid from outside the fluid cartridge into the respective first and third fluid channels;

a sample inlet for placing a sample within the path of the first or second fluid channel, the sample inlet being disposed separately from the first and second inlets;

a first plug disposed at the first inlet and comprising a flexible material configured to be traversed by a capillary tube without leakage of fluid through the first plug.

2. The fluidic cartridge of claim 1, wherein the semiconductor chip further comprises analog circuitry related to operation of the sensor array.

3. The fluidic cartridge of claim 1, wherein the sample inlet is disposed between the first inlet and the first outlet of the first fluidic channel.

4. A fluid cartridge according to claim 3, further comprising a second plug disposed at the second inlet and comprising a flexible material configured to be passed through by the capillary without leakage of the fluid through the second plug.

5. The fluidic cartridge of claim 4, wherein the first and second plugs are configured to align with first and second capillaries connected to the analyzer, and a plurality of contact pads are connected with the analyzer when the fluidic cartridge and the analyzer are in physical contact.

6. The fluidic cartridge of claim 5, wherein the first and second capillaries pass through the first and second plugs, respectively, when the fluidic cartridge and the analyzer are in physical contact.

7. The fluid cartridge of claim 1, wherein the substrate is a printed circuit board.

8. The fluidic cartridge of claim 1, further comprising a waste chamber connected to the second fluidic channel.

9. The fluidic cartridge of claim 1, wherein one or more sensors in the sensor array comprise a plurality of probe molecules configured to bind to target molecules present in the sample.

10. The fluidic cartridge of claim 1, wherein said sensor array comprises a dual gate backside sense FET sensor array.

11. A fluid cartridge, comprising:

a first fluid channel having a first inlet and extending from the first inlet to a second fluid channel, the second fluid channel aligned such that a sensor array and a reference electrode are disposed within the second fluid channel;

a third fluid channel having a second inlet extending from the second inlet to the second fluid channel, wherein the first and second inlets are both for injecting fluid from outside the fluid cartridge into the respective first and third fluid channels;

a sample inlet for placing a sample within the path of the first or second fluid channel, the sample inlet being disposed separately from the first and second inlets;

a first plug disposed at the first inlet and comprising a flexible material configured to be traversed by a capillary without leakage of fluid through the first plug, wherein the capillary is connected to an analyzer and the capillary traverses the first plug when the fluidic cartridge is in physical contact with the analyzer.

12. The fluidic cartridge of claim 11, wherein said sensor array comprises a dual gate backside sense FET sensor array.

13. The fluidic cartridge of claim 11, wherein one or more sensors in the sensor array comprise a plurality of probe molecules configured to bind to target molecules present in the sample.

14. The fluidic cartridge of claim 13, wherein said plurality of probe molecules comprises one or more of DNA, RNA, and antibodies.

15. The fluid cartridge of claim 11, further comprising: having a plurality of contact pads configured to electrically connect with the analyzer, a semiconductor chip having the sensor array, and a reference electrode.

16. An analyzer configured to be coupled to a fluidic cartridge, the analyzer comprising:

a syringe arranged such that when the fluid cartridge is physically connected to the analyzer, a needle of the syringe is aligned with a corresponding input port of the fluid cartridge;

an actuator configured to control operation of the injector;

a sensing module configured to send and receive signals to and from the fluidic cartridge via a plurality of conductive pads when the fluidic cartridge is physically connected to the analyzer, wherein the plurality of conductive pads contact a corresponding plurality of conductive pads on the fluidic cartridge; and

a processor electrically connected to the sensing module and configured to determine a concentration level of a given analyte from a sample in the fluidic cartridge based on a signal received from the fluidic cartridge;

the fluid cartridge includes:

a semiconductor chip having a sensor array;

a first fluid channel having a first inlet and extending from the first inlet to a second fluid channel, the second fluid channel aligned such that the sensor array and reference electrode are disposed within the second fluid channel;

a third fluid channel having a second inlet extending from the second inlet to the second fluid channel, wherein the first and second inlets are both for injecting fluid from outside the fluid cartridge into the respective first and third fluid channels;

a sample inlet for placing a sample within the path of the first fluid channel or the second fluid channel, the sample inlet being disposed separately from the first inlet and the second inlet.

17. The analyzer according to claim 16 further comprising an actuator controller configured to control operation of the actuator.

18. The analyzer according to claim 17, wherein said processor is further electrically connected to said actuator controller.

19. The analyzer according to claim 16, further comprising at least one other syringe arranged such that a needle of the at least one other syringe is aligned with a corresponding input port of the fluid cartridge when the fluid cartridge is physically connected to the analyzer.

20. The analyzer of claim 16, further comprising a memory configured to store data related to the concentration level of a given analyte determined by the processor.

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