Detection and motion detection of 2D nanoparticles

Abstract

Detection and motion detection of 2D nanoparticles. Devices and methods for detecting the presence of an analyte contained in a medium and / or monitoring its movement. More specifically, a microcapacitance sensing system including a planar microcapacitance sensor array is provided for detecting the presence of an analyte in a sample medium. The sensor structure for detecting, recognizing or tracking the movement of a substance includes an upper planar substrate having a first array of non-contact planar conductive electrodes, and a lower planar substrate having a second array of non-contact planar conductive electrodes aligned with and overlapping the corresponding electrodes of the first array. The overlapping conductive electrodes are triangular in order to maximize the perimeter area ratio. The first and second planar substrates are parallel, sealed, and define a volume between them to receive a medium containing the analyte to be detected or monitored. Detection of movement is achieved by measuring the change in capacitance between the electrodes of the upper substrate and the aligned electrodes of the lower substrate.

Description

[Technical Field]

[0001] This application relates to devices, systems and methods for detecting the presence and / or movement of an analyte. More specifically, this application relates to structures and systems including a microcapacitive image sensor array for detecting the presence and / or movement of scaled substances such as viruses, bacteria, cells, nanoparticles, or other molecules or compositions. [Background technology]

[0002] In process tomography and tomography imaging systems, a full range of principles and techniques are available, including electrical methods based on impedance measurement, ultrasonic magnetic resonance, optical methods, and methods based on ionizing radiation (X-rays and gamma rays). Ionizing radiation methods produce the highest resolution images, but are relatively slow and not dynamic for practical use. Optical particle size detection is limited to >0.5 μm, which is the diffraction limit of the light wavelength used.

[0003] Electrotomy systems and methods, while producing low-resolution images unsuitable for nano-sized particles, are much faster, more robust, and relatively inexpensive.

[0004] Currently, as shown in Figure 1, electrical capacitance imaging (ECI) systems such as the sensing system 50 are designed to be used with circular (i.e., out-of-plane) sensor electrodes 52, which typically have 6, 8, 12, or 16 electrodes surrounding a fluidization bed or bubble row 55, in order to visualize volumetric flow through a 3D arrangement of sensors. To image the movement with these electrodes 52, n(n-1) / 2 capacitance measurements must be performed independently. [Overview of the project]

[0005] In one aspect of this disclosure, a microcapacitive sensor array structure and a detection method adapted for two-dimensional (2D) nanoparticle size capacitive image detection are provided.

[0006] Microcapacitive sensor array structures and methods detect the type and movement of matter, particularly minute particles / substances of viruses, bacteria, cells, nanoparticles, or other molecular compositions with a dielectric constant different from that of the surrounding medium.

[0007] Furthermore, a device / chip structure is provided that pushes down the limits of particle detection size in order to detect minute particles / substances such as viruses, bacteria, cells, nanoparticles, or other molecules via electrical impedance / capacitance.

[0008] Microcapacitive sensor arrays can include structures that maximize the peripheral area ratio and fill factor of the sensor electrodes to achieve the best trade-off between signal-to-noise ratio (SNR) and spatial resolution.

[0009] This invention relates to a data sensor for an electrotomy system that offers high resolution, a high signal-to-noise ratio (accuracy), rapid image reconstruction, and supports motion analysis in real-time images; and reduces the number of measurements required per image.

[0010] In one aspect of the present disclosure, a microcapacitive sensor is provided. The microcapacitive sensor array comprises: a first two-dimensional (2D) array of non-contact conductive electrodes, each formed on a first electrode surface according to a maximum peripheral area ratio; and a second 2D array of non-contact conductive electrodes, each formed on a second electrode surface according to a maximum peripheral area ratio, wherein the first and second electrode surfaces overlap and are parallel, and each conductive electrode of the first 2D array and the corresponding conductive electrode of the second 2D array are aligned and separated to define a channel between them, such that a substance to be analyzed is detected between the first and second electrode surfaces.

[0011] In another aspect of this disclosure, a system for detecting a substance to be analyzed is provided. The system comprises a microcapacitive sensor, the microcapacitive sensor having: a first two-dimensional (2D) array of non-contact conductive electrodes, each formed according to the maximum outer area ratio on a first electrode surface; and a second 2D array of non-contact conductive electrodes, each formed according to the maximum outer area ratio on a second electrode surface, wherein the first and second electrode surfaces overlap and are parallel, and each conductive electrode of the first 2D array and the corresponding conductive electrode of the second 2D array are aligned and separated to define a channel between them, such that the substance to be analyzed is detected between the first and second electrode surfaces; and further having one or more respective conductive signal lines in contact with each of the non-contact conductive electrodes along each single row or column of the first 2D array of non-contact conductive electrodes; and one or more respective conductive signal lines in contact with each of the non-contact conductive electrodes along each single column or row of the second 2D array of non-contact conductive electrodes.

[0012] In yet another embodiment of the present application, a method for manufacturing a microcapacitive sensor is provided. The method is: providing a first insulating substrate; forming a two-dimensional (2D) array of first conductive electrodes on the surface of the first insulating substrate, each formed according to the maximum perimeter area ratio and spaced apart from one another; forming corresponding conductive signal lines on opposing surfaces of the first insulating substrate, each corresponding to each row of first electrodes in the 2D array, such that each conductive signal line connects to one or more of the first capacitor electrodes along the respective row of the 2D array by via connections formed through the first insulating substrate; providing a second insulating substrate; forming a second array on the surface of the second insulating substrate, each formed according to the maximum perimeter area ratio and spaced apart from one another The method comprises the steps of: forming a two-dimensional (2D) array of two conductive electrodes; forming conductive signal lines on opposing surfaces of the second insulating substrate, corresponding to each row of the second electrodes of the 2D array, such that each conductive signal line is connected to one or more of the second capacitor electrodes along each row of the 2D array by via connections formed through the second insulating substrate; and joining the first insulating substrate and the second insulating substrate using an insulating material, such that the first conductive electrode of the first 2D array of capacitor electrodes is aligned with the corresponding second conductive electrode of the second 2D array and separated to define a channel between them. [Brief explanation of the drawing]

[0013] Herein, embodiments of the present invention will be described merely as examples with reference to the accompanying drawings. [Figure 1] This shows a conventional capacitive imaging (ECI) system designed for use with circular (i.e., out-of-plane) sensor electrodes. [Figure 2] This is a top view of a microcapacitive sensor structure for detecting 2D nanoparticle material and its movement, according to one embodiment of the present invention. [Figure 3]An exploded view showing an upper insulating substrate including a first set of conductive electrodes oriented as a single metal layer in a first plane, and a corresponding bottom insulating substrate including a second set of conductive electrodes oriented as a single metal layer in a second plane. [Figure 4] A bottom view showing the assembled microcapacitor sensor structure of FIG. 2, where the illustrated assembled substrate has the upper substrate and the bottom substrate slightly misaligned, and for simplicity of illustration, the first set of upper substrate electrodes and the second set of bottom substrate electrodes are shown as being slightly misaligned in the overlapping portion. [Figure 5] A partial cross-sectional view of the microcapacitance sensor structure of FIG. 4 along the section line A-A'. [Figure 6] A bottom view showing the assembled second embodiment of a microcapacitor sensor structure including an upper substrate with triangular planar electrodes and a bottom substrate with triangular planar electrodes. [Figure 7] FIG. 7A is a partial cross-sectional view of the microcapacitance sensor structure of FIG. 6 along the section line B-B'. FIG. 7B is a partial cross-sectional view of the microcapacitance sensor structure of FIG. 6 along the section line C-C'. [Figure 8] An exploded view before assembly showing a double-metal-layer upper insulating substrate including a first set of conductive triangular electrodes oriented as a single metal layer in a first plane and having external electrode signal line connections to each electrode in a second metal layer (second plane). [Figure 9] A bottom view showing the assembled substrate of FIG. 8 for forming a microcapacitance sensor structure according to a further embodiment, where for purposes of non-limiting illustration, the assembled substrate is shown as having the upper substrate and the bottom substrate slightly misaligned for simplicity of illustration. [Figure 10] A partial cross-sectional view of the microcapacitance sensor structure of FIG. 9 along the section line D-D'. [Figure 11] A system for detecting an analyte according to an embodiment of the present application that employs an integrated microcapacitance detection circuit is shown.

Mode for Carrying Out the Invention

[0014] Here, the present application will be described in more detail by referring to the following discussion and the accompanying drawings of the present application. Note that the drawings of the present application are provided for illustrative purposes only, and thus the drawings are not to scale. Also note that similar corresponding elements are referred to by similar reference numerals.

[0015] In the following description, numerous specific details of certain structures, components, materials, dimensions, processing steps, and techniques, etc. of various embodiments of the present application are set forth in order to provide an understanding of the various embodiments of the present application. However, those skilled in the art will understand that the various embodiments of the present application can be implemented without these specific details. In other instances, well-known structures or processing steps are not described in detail so as to avoid obscuring the present application.

[0016] When an element as a layer, region, or substrate is said to be "on" or "over" another element, it will be understood that the element can be directly on the other element or intervening elements may be present. In contrast, when an element is said to be "on" or "directly over" another element, no intervening elements are present. When an element is said to be "beneath" or "under" another element, it will be understood that the element can be directly beneath or under the other element or intervening elements may be present. In contrast, when an element is said to be "directly beneath" or "directly under" another element, no intervening elements are present.

[0017] FIG. 2 shows an exemplary 2D nanoparticle motion sensing structure and method according to an aspect of the present disclosure.

[0018] As shown in Figure 2, a top view of a microcapacitive sensor structure 100 for detecting 2D nanoparticle material and its movement is illustrated. The sensor structure 100 includes an upper insulating substrate 101 containing a first two-dimensional (2D) array of conductive planar electrodes 105 oriented on a first electrode surface. Each of the first conductive electrodes 105 is molded to provide a maximum perimeter area ratio. In one embodiment, the maximum perimeter area ratio corresponds to a triangle. In another embodiment, the maximum perimeter area ratio corresponds to an equilateral triangle. The sensor structure 100 further includes a bottom insulating substrate 121 containing a corresponding 2D array set (second set) of bottom conductive planar electrodes (not shown) oriented and aligned on a second plane. In one embodiment, the insulating substrates 101, 121 can be formed from glass, plastic, or organic printed circuit boards. Furthermore, in Figure 2, the first set of electrodes 105 is aligned to just overlap with the corresponding set of bottom conductive electrodes. The bottom conductive electrodes are also molded to provide a maximum perimeter area ratio. In one embodiment, the maximum perimeter area ratio corresponds to a triangle.

[0019] In one embodiment, miniaturization of the sensor enables the detection of smaller particles and microorganisms such as bacteria, thereby improving both accuracy and resolution. Sensor scaling is constrained by limitations such as (1) minimum area sensor feature patterning defined by state-of-the-art (microelectronic) manufacturing technology, (2) obtaining the maximum perimeter area ratio or surface area-to-volume ratio in 2D or 3D detection, respectively, and (3) maximizing the fill factor through the sensor's shape. These three requirements provide the best spatial image resolution by maintaining the minimum area while increasing the perimeter, which is proportional to the measured signal capacity.

[0020] In one embodiment, by maximizing the area / region ratio, or equivalently minimizing its reciprocal, i.e., minimizing the area / perimeter (A / P) ratio of an equilateral triangle using S as the minimum semiconductor manufacturing feature size, it is found to be equal to 0.144S, which is confirmed to be smaller than the A / P ratio of a square electrode (=0.25S), or the A / P ratio of a hexagonal electrode (=0.433S), or a circle (=0.5S). Thus, as referred to herein, “maximum perimeter area ratio” refers to the triangular electrodes 105, 125 that provide the smallest A / P ratio compared to other geometric figures with the same minimum dimension S (feature size) value for the corresponding sides.

[0021] In embodiments, the conductive planar electrodes 105 and 125 are made of a metallic material such as copper, aluminum, or titanium. In embodiments, the conductive planar triangular electrodes 105 and 125 may generally include transparent conductive films in the form of indium tin oxide (ITO), fluorine-doped tin oxide (FTO), and doped zinc oxide.

[0022] As further shown in Figure 2, a plurality of interconnecting conductive signal lines or external conductive traces 110 ("signal lines") formed within or on the upper substrate 101 are illustrated, each signal line 110 oriented along and in contact with each single row 111 of electrodes 105 and the plurality of electrodes 105. In a non-limiting and exemplary embodiment of the sensor 100 shown in Figure 2, there are eight electrodes 105 along each row 111, and eight rows of electrodes 105 and corresponding eight external conductive signal lines 110 are shown. Along each row 111, the electrodes 105 are configured as a series of pairs, for example electrodes 105A and 105B, where the bases of each pair face each other but are separated by a short insulating gap. As a result, the vertices of each triangular electrode of pair 105A and 105B point in opposite directions, and the pair covers a square region. Similarly, as shown in Figure 2, there are multiple interconnecting conductive signal lines or external conductor traces 130 ("signal lines") formed within or on the bottom substrate 121, each signal line oriented along and in contact with multiple bottom electrodes (not shown) along a single row. Although not shown, one or more dielectric materials are formed between the top substrate 101 and the bottom substrate 121. The dielectric provides electrical insulation and possible isolation from the formed microfluidic channel by the separation between the top substrate 101 and the bottom substrate 121, which is shown as d in Figure 5. These dielectrics may be commonly available microelectronic films such as silicon dioxide, silicon nitride, low-k dielectrics (where k is a dielectric constant less than 4), or polyimide or other similar films. The thickness of these dielectric films ranges from nanometers to microns, and is typically 0.1 to 1 micron, depending on the deposition method and also on the electrical and chemical barriers required from the analyte in the microfluidic channel 175. The separation of the upper substrate 101 from the lower substrate 121 depends on the particle size detected in the analyte in the microfluidic channel 175, which is typically within a range of particle size diameters.Particles range from nanoparticles such as proteins (typically >5 nm) to viruses (typically 0.1 to 0.2 microns or smaller), bacteria (typically submicrons to 5 microns), plant or animal cells (typically 10 to 100 microns), and larger particles of interest.

[0023] Figure 3 is an exploded view showing an upper insulating substrate 101 containing a first set 105 of conductive electrodes oriented as a single metal layer in a first plane, and a corresponding bottom insulating substrate 121 containing a second set 125 of conductive electrodes oriented as a single metal layer in a second plane. As better shown in Figure 3, a plurality of external conductive signal lines 130 formed in or on the bottom substrate 121 are shown, each external signal line 130 oriented along a plurality of electrodes 125 along each single row 131 of electrodes 125 and in contact with them. In the non-limiting and exemplary embodiment shown in Figure 3, there are eight electrodes 125 along each row 131, and eight rows of electrodes and corresponding eight external conductors 130 are shown. Along each row 131, the electrodes 125 are configured as a series of pairs, for example electrodes 125A, 125B, with the sides of each pair facing each other but separated by a short insulating gap. As a result, the vertices of each triangular electrode in pair 125A and 125B point in opposite directions, and the pair covers a parallelogram region. In Figure 3, in any specific row or column 111, 131 of the electrodes, each conductive electrode is electrically insulated from any other electrode, and the rows and columns of triangular electrodes in the 2D array on each substrate take on a close-packed structure that maximizes electrode coverage.

[0024] In one embodiment, n / 2 electrodes are provided on each of the upper and lower substrates. In this configuration, the number of capacitance measurements that can be independently used for a total of n electrodes is n / 2. By superimposing the upper insulating substrate 101 on the lower insulating substrate 121, the structure 100 of Figure 1 is obtained.

[0025] Figure 4 is a bottom view showing the assembled microcapacitor sensor structure 100 of Figure 2. However, the assembled substrate shown has a slight misalignment between the upper and lower substrates. For the sake of simplicity, the first set of upper substrate electrodes 105 and the second set of lower substrate electrodes 125 are shown as being slightly misaligned in their overlapping portions. In this embodiment, each individual planar upper electrode 105 of the electrode set on the upper substrate 101 is aligned to precisely overlap with the corresponding individual planar lower electrode 125 of the electrode set on the lower substrate 121.

[0026] In the embodiment, as shown in Figure 4, which is slightly offset for clarity and shows the bottom to top, the capacitance microsensor 100 is formed by a 2D array of individual aligned pairs of upper electrodes (e.g., electrode 105A) and aligned bottom electrodes (e.g., bottom electrode 125A) overlapping. The 2D array of all planar upper electrodes 105 and the corresponding aligned planar bottom electrodes 125 forms a microsensor that is used to image fluid changes in dielectric constant, but it can be used to monitor, identify and / or track the movement of particles or organisms including, but not limited to, extremely small particles (e.g., nanoparticles <200 nm), small molecules, biomarkers, DNA, proteins, or organisms such as bacteria, viruses, plant cells, animal cells, or other molecules or formulations with a dielectric constant different from the surrounding medium. The 2D arrangement of electrodes 105, 125 allows n / 2 independent capacitance measurements to be performed to image the movement of particles or organisms. However, the 100 sensors are scalable for large-scale scaling applications (e.g., detecting the percentage of water / liquid fluid or pneumatic transmission flow inside oil or gas pipelines, flames during combustion, gravity flow in silos, and imaging immiscible liquid mixtures such as various chemicals, one of which may be contaminants).

[0027] In the embodiment shown in Figure 4, although not shown, there is a single contact for the output of each upper-plane electrode along each electrode row 111, i.e., there is one electrode row per output contact. That is, along each row of electrodes 105, a single signal line or trace 112 contacts each electrode 105 along that row. In other words, along each row of electrodes 105, the single signal line 112 contacts each electrode 105 along that row, and if a change in the relative permittivity between any aligned pair of electrodes 105, 125 is detected along that row, it captures and transmits it. Similarly, there is a single contact for the output of each bottom-plane electrode along each row 131 of electrodes, i.e., there is one electrode row per output contact. That is, along each row of electrodes 125, a single signal line or trace 132 contacts each electrode 125 along that row, and if a change in the relative permittivity between any aligned pair of electrodes is detected along that row, it captures and transmits it. Thus, in the exemplary embodiment shown in Figure 4, the number of independently available capacitance measurements or detected dielectric constant changes is n / 2 / 8, where n / 2 is the total number of planar upper electrodes (e.g., 64) or planar bottom electrodes (e.g., 64).

[0028] Figure 5 is a cross-sectional view of a portion 150 of the microcapacitive sensor structure 100 of Figure 4 along the cross-sectional line A-A'. As shown in Figure 5, the upper substrate 101 is shown below the bottom insulating substrate 121 and is shown to include a portion of external conductive signal lines 112 oriented in a first plane. The second substrate 121 is shown to include a portion of external conductive signal lines 132 oriented in a second plane parallel to the first plane. As shown in Figure 5, one or more insulating spacer structures are formed at intervals to form, for example, a ring or gasket 161, which connects the upper substrate 101 to the bottom substrate 121 and allows for separation or a channel between the upper substrate 101 and the bottom substrate 121. The insulating spacer structure or gasket 161 may be an epoxy or any insulating structure that functions as a sealant and is designed to seal an area containing a liquid medium having particles or biological material for capacitance sensing. An insulating spacer structure or gasket 161 can be formed on each upper and lower substrate, or near the peripheral edge, to define a cavity or channel 175 between the upper substrate 101 and the lower substrate 121, within which a liquid medium is contained or flows. The gasket 161 may have two discontinuities in otherwise continuous sealing, for example, having an analyte inlet port and an analyte outlet port (not shown) on the analyte side. As a second example, the gasket 161 may have a continuous sealing that bypasses electrodes 105, 125, where the analyte inlet and outlet ports are through holes from the upper substrate 101, the lower substrate 121, or both (not shown).

[0029] In one embodiment, the distance between the bottom substrate and the top substrate, and the corresponding distance between the respective electrodes 105 and 125, are equivalent to the size of the particles or organisms detected at microcapacitance, and the distance d may be in the range of submicrons or less to millimeters or more.

[0030] Figure 6 is a bottom view showing an assembled second embodiment of a microcapacitive sensor structure 200, including an upper substrate 201 for triangular planar electrodes 105 and a bottom substrate 221 for triangular planar electrodes 125. In Figure 6, the assembled substrates 201 and 221 are shown with the upper and bottom substrates slightly offset for simplification of the illustration, resulting in a slight misalignment in the overlapping portion of the first set of upper substrate electrodes 105 and the second set of bottom substrate electrodes 125. In this embodiment, each individual electrode 105 of the electrode set on the upper substrate 201 is aligned to precisely overlap the corresponding individual electrode 125 of the electrode set on the bottom substrate 221.

[0031] In one embodiment, as shown in Figure 6, which is slightly offset for clarity and shows the bottom to top, the capacitive microsensor 100 is formed by a 2D array of individual, aligned pairs of planar upper electrodes (e.g., electrode 105A) and bottom electrodes (e.g., planar bottom electrode 125A) overlapping. The 2D array of all planar upper electrodes 105 and the corresponding aligned planar bottom electrodes 125 forms a capacitive microsensor used to image fluid changes in dielectric or dielectric constant, and can be used to monitor, identify and / or track the movement of particles or organisms. The 2D arrangement of electrodes 105, 125 allows for n / 2 independent capacitance measurements or detection of changes in dielectric constant measurements to image the movement of particles or organisms. However, the sensor is scalable for large-scale scaling applications.

[0032] In the embodiment shown in Figure 6, although not shown, each row 111 of the planar upper electrode 105 has two electrically connected electrode signal lines per row. That is, for each row 111 of the planar upper electrode 105, half of the electrodes in row 111 (for example, the four electrodes in the shown embodiment) are connected to a first external conductive signal line 212A via their respective interconnect vias or through via connections, and the remaining half of the electrodes in the same row 111 are each connected to a second external conductive signal line 212B via their respective interconnect vias or through via connections. Specifically, along each row of electrodes 105, the first conductive signal line 212A contacts each half of the electrodes 105 along the row, and when a change in the relative permittivity between arbitrarily aligned pairs of electrodes 105 and 125 is detected from any half of the electrodes along that row, it is captured and transmitted. The second signal line 212B contacts each of the remaining halves of the electrodes 105 along row 111, and when a detected change in the relative permittivity between arbitrarily aligned pairs of electrodes 105 and 125 is detected from the remaining electrodes along that row, it is captured and transmitted.

[0033] Similarly, each row 131 of the planar bottom electrode 125 has two connected electrode signal lines per row. Specifically, along each row 131 of the electrode 125, there is a first electrode signal line 232A that provides output contacts to through-via connections at each electrode in the first half of the electrodes in row 131 (for example, the four electrodes in the shown embodiment), and a second electrode signal line 232B that provides output contacts to through-via connections at each electrode in the remaining half of the electrodes in the same row 131. Specifically, along each row of electrodes 125, the first signal line 232A contacts each half of the electrodes 125 along the row, and when a change in the relative permittivity between any arbitrarily aligned pairs of electrodes 105, 125 is detected from any of the electrode pairs along that half of the row, it is captured and transmitted. The second signal line 232B contacts each of the remaining half of electrodes 125 along row 131, and when a change in the relative permittivity between any arbitrarily aligned pairs of electrodes 105, 125 is detected from the remaining pairs of electrodes along that row, it is captured and transmitted.

[0034] In one embodiment shown in Figure 6, n / 2 electrodes are provided on each of the upper and bottom substrates. In this configuration, the number of capacitance measurements that can be performed independently is n / 2, where n / 2 is the total number of planar upper electrodes (e.g., 64 in the exemplary embodiment) or the total number of planar bottom electrodes (e.g., 64). By superimposing the upper insulating substrate 101 on the bottom insulating substrate 121, the structure 100 of Figure 1 is obtained.

[0035] Figure 7A is a cross-sectional view of a portion 250 of the microcapacitive sensor structure 200 of Figure 6 along the cross-sectional line B-B'. As shown in Figure 7A, the upper substrate 101 is shown below the bottom insulating substrate 121. In the cross-section along line B-B' of Figure 6, a double metal layer substrate structure 101 is shown, including a first layer of upper planar electrodes 105 (e.g., eight planar electrodes along the row in the exemplary embodiment) along the bottom surface of the substrate 101, each electrode having a conductive contact through-via connection 205 that penetrates the substrate 101 and extends to the opposite surface of the substrate. In the cross-section of Figure 7A along line B-B' of Figure 6, one of the planar upper electrodes 105 has a through-via connection 205 that connects to a second single external signal line 212B on the opposite surface of the substrate (the other metal layer).

[0036] As further shown in Figure 7A, in a cross-section along line B-B' in Figure 6, the double metal layer bottom substrate 121 is shown above the upper insulating substrate 101. Further shown is a double metal layer substrate structure 121 including a first layer of bottom planar electrodes 125 (e.g., eight planar electrodes along a row in the exemplary embodiment) along the top surface of the substrate 121, each bottom planar electrode 125 having a conductive contact through-via connection 225 extending from the electrode 125 through the substrate 121 to the opposite surface of the substrate (another metal layer). The first half of the planar bottom electrodes 125 (e.g., four electrodes) each has a conductive through-via connection 225 connected to a first single external signal line 242A, and the remaining half of the planar bottom electrodes 125 (e.g., the remaining four electrodes) each has a through-via connection 225 in contact with a separate single external signal line 242B.

[0037] Figure 7B is a cross-sectional view of a portion 275 of the microcapacitive sensor structure 200 of Figure 6 along the cross-sectional line C-C'. As shown in Figure 7B, the upper substrate 101 is shown below the bottom insulating substrate 121, although both substrates are configured to have a double metal layer. In the cross-section along line C-C' of Figure 6, planar upper electrodes 105 (e.g., eight planar electrodes along the row in the exemplary embodiment) are shown along the bottom surface of the substrate 101, and each electrode has a conductive contact through-via connection 205 that penetrates the substrate 101 from the electrode 105 and extends to the opposite surface of the substrate. In the cross-section of Figure 7B along line C-C' of Figure 6, the first half of the planar upper electrodes 105 (e.g., four electrodes) each has a conductive through-via connection 205 connected to a first single external signal line 221A. Furthermore, the remaining half of the planar upper electrodes 105 (e.g., the remaining four electrodes) each has a through-via connection 205 connected to a separate single external signal line 221B.

[0038] In Figure 7B, which shows a cross-section of the microcapacitive sensor structure 200 of Figure 6 along line C-C', planar bottom electrodes 125 along the bottom surface of the substrate 121 (e.g., eight planar electrodes along a row in an exemplary embodiment) are further shown, each electrode 125 having a conductive contact through-via connection 225 that penetrates the substrate 121 from the electrode 125 and extends to the opposite surface of the substrate. In the cross-section of Figure 7B along line C-C' of Figure 6, one of the planar top electrodes 125 is shown having a through-via connection 205, which is shown as being connected to a second single external signal line 231.

[0039] In the embodiments illustrated in Figures 7A and 7B, one or more spaced insulating spacer structures or gaskets 161 are shown that connect the upper substrate to the bottom substrate 121, allowing separation of the upper substrate 101 and the bottom substrate 121. These insulating spacer structures or gaskets 161 may be epoxy or any insulating structure that functions as a sealant and is designed to seal an area containing a liquid medium having particles or organisms inside for capacitance sensing. The distance between the bottom substrate 121 and the upper substrate 101, and the corresponding distance between the respective electrodes 105, 125, are equivalent to the size of the particles or organisms to be detected at microcapacitance, and the distance d may be on the order of submicrons or less to millimeters or more.

[0040] Figure 8 is an exploded view before assembly showing a double metal layer upper insulating substrate 301, which includes a first set of conductive triangular electrodes 105 oriented as a single metal layer in the first plane, and has external electrode signal line connections 310 to each electrode in the second metal layer (second plane). The corresponding double metal layer bottom insulating substrate 321 includes a second set of conductive triangular electrodes 125 oriented as a single metal layer in the first plane, and has external electrode signal line connections 330 to each electrode in the second metal layer (second plane).

[0041] In one embodiment, as shown in Figure 8, a plurality of external conductor signal line sets 310 are formed on the upper substrate 301, and each set 310 is connected to each triangular electrode 105 along a row 111 of electrodes 105. In one embodiment, a set 310 has four external electrode conductive signal lines 110, each of the four external electrode conductor signal lines is oriented along and in contact with a plurality of four electrodes 105, and along each single row 111 of electrodes 105 there is one conductive signal line set 310 from the bottom and one conductive signal line set 310 from the top. In the non-limiting and exemplary embodiment shown in Figure 8, there are eight electrodes 105 along each row 111, and eight electrode rows and corresponding 64 external conductors 110 are shown. In the non-limiting and exemplary embodiment shown in Figure 8, there are 16 sets 310, each set having four electrode connection signal lines 110, and two sets 310 are connected to each electrode along each single row 131. In Figure 8, in any specific electrode array 111, each conductive electrode 105 is electrically isolated from any other electrode.

[0042] Similarly, in one embodiment, as shown in Figure 8, a plurality of external conductor signal line sets 330 are formed on the upper substrate 321, with two sets of signal lines 330 connected to each triangular electrode 125 along a row 131 of electrodes 125. In one embodiment, a set 330 has four external electrode conductors 130, and two sets of the four external electrode conductors are oriented along and in contact with a plurality of electrodes 125 along each single row 131 of electrodes 125. In the non-limiting and exemplary embodiment shown in Figure 8, there are eight electrodes 125 along each row 131, and eight electrode rows and corresponding 64 external conductors 130 are shown. Thus, in the non-limiting and exemplary embodiment shown in Figure 8, there are eight sets 330, each set having four electrode connection signal lines 130, and each set 330 is connected to each electrode along each single row 131. In Figure 8, in any particular electrode row 131, each conductive electrode 125 is electrically isolated from any other electrode.

[0043] In one embodiment, n / 2 electrodes are provided on both the upper and lower substrates. In this configuration, the number of capacitance measurements or detections of changes in relative permittivity measurements that can be performed independently for a total of n electrodes is n / 2.

[0044] Figure 9 shows a bottom view of the assembled substrates 301 and 321 of Figure 8 forming the microcapacitive sensor structure 300. However, for non-limiting and illustrative purposes, the assembled substrates shown are slightly offset between the upper and lower substrates, and for simplification of the illustration, the first set of upper substrate electrodes 105 and the second set of lower substrate electrodes 125 are shown as slightly offset in the overlapping portion. In this embodiment, each individual planar upper electrode 105 of the electrode set on the upper substrate 301 is aligned to just overlap with the corresponding individual planar lower electrode 125 of the electrode set on the lower substrate 321.

[0045] In an embodiment, as shown in Figure 9, which is slightly offset for clarity and shows the bottom to top, the capacitive microsensor 300 is formed by a double-metallic layered, individually aligned paired 2D array, which is the overlap of an upper electrode (e.g., electrode 105A) and an aligned bottom electrode (e.g., bottom electrode 125A). The 2D array of all planar upper electrodes 105 and the corresponding aligned planar bottom electrodes 125 forms a microsensor used to image fluid changes in dielectric constant and can be used to monitor, identify and / or track the movement of particles or organisms. The 2D arrangement of electrodes 105, 125 allows for n / 2 independent capacitance measurements or detection of changes in dielectric constant measurements between any aligned pair of electrodes 105, 125 to image the movement of particles or organisms. However, the sensor 300 is scalable for large-scale scaling applications.

[0046] In the embodiment shown in Figure 9, there is a single contact for each output of each planar upper electrode 105 along each electrode row 111, i.e., there is one electrode per output contact. Specifically, along each row 111 of electrodes 105, there are two sets of 310 of 4 single signal line conductors 110 (i.e., 4 single signal line conductors 110 from the top and 4 single signal line conductors 110 from the bottom), which contact each individual electrode 105 along each row, and capture and transmit any change in dielectric constant detected between any pair of electrodes 105, 125 along that row. Similarly, there is a single contact for each output of each planar bottom electrode 125 along each electrode row 131, i.e., there is one electrode row per output contact. Specifically, along each row of electrodes 125, there is a set 330 consisting of two sets of four single signal line conductors 130 (i.e., four single signal line conductors 130 from the left and four single signal line conductors 130 from the right), and the set 330 is in contact with each individual electrode 125 along each row 131, and when a change in relative permittivity is detected between any pair of electrodes 105, 125 along that row, it captures and transmits it.

[0047] In one embodiment shown in Figure 9, n / 2 electrodes are provided on each of the upper and bottom substrates. In this configuration, the number of independently available capacitance measurements is n / 2, where n / 2 is the total number of planar upper electrodes (e.g., 64 in the exemplary embodiment) or the total number of planar bottom electrodes (e.g., 64). By superimposing the upper insulating substrate 101 on the bottom insulating substrate 121, the structure 100 of Figure 1 is obtained.

[0048] Figure 10 is a cross-sectional view of a portion 350 of the microcapacitive sensor structure 300 of Figure 9 along the cross-sectional line D-D'. As shown in Figure 10, the upper double metal layer substrate 101 is shown below the lower double metal layer insulating substrate 121. In the cross-section along line D-D' in Figure 9, the double metal layer substrate structure 101 is shown including a first layer of upper planar electrodes 105 (e.g., eight planar electrodes along the row in the exemplary embodiment) along the bottom surface of the substrate 101, each individual electrode having a conductive contact through-via connection 205 that penetrates the substrate 101 from a single electrode 105 and extends to the opposite surface of the substrate. In the cross-section of Figure 10 along line D-D' in Figure 9, one of the upper planar electrodes 105 has a set of four interconnection lines 310 on the opposite side of 101, but there is only one via connection 205 per electrode 105, and one via connection 205A connects to a separate single external conductive signal line in a group of four external conductive signal lines 312 on the opposite surface of the substrate (another metal layer). It is understood that for any electrode, each of the individual via connections 205 of set 310 connects to a different separate single external conductive signal line.

[0049] As further shown in Figure 10, in a cross-section along line D-D' of the microcapacitive sensor structure 300 of Figure 9, the double metal layer bottom substrate 121 is shown above the upper insulating substrate 101. The double metal layer substrate includes a first layer of bottom planar electrodes 125 (e.g., eight planar electrodes along the row in the exemplary embodiment) along the top surface of the substrate 121, and each bottom planar electrode 125 has one conductive contact via a via connection 225 that extends from the electrode 125 through the substrate 121 to the opposite surface of the substrate (another metal layer). In one embodiment shown in Figure 10, each electrode 125 along row 131 has one conductive through-via connection 225. One electrode 125 of the left group of four electrodes connected to the first single external signal lines 342A and 342B, and one electrode 125 of the right group of four electrodes are shown.

[0050] Various methods may be used in constructing the microcapacitor sensors 100, 200, and 300 illustrated in Figures 4, 6, and 9. In one embodiment, the method includes the step of forming a two-dimensional (2D) array of separated upper electrodes 105 having dimensions of the maximum outer peripheral area on the upper substrate. In one embodiment, the upper electrodes 105 are equilateral triangles and are arranged as parallel rows or columns of multiple electrodes. The upper substrate 101 may be rigid or flexible and may include, for example, an insulating layer on a semiconductor material or an electrically insulating material such as glass or polymer. Exemplary semiconductor materials that may be used in this application as the upper substrate 101 include, but are not limited to, Si, Ge, SiGe, SiGeC, SiC, GaSb, GaP, GaN, GaAs, InAs, InP, AlN, and all other III-V or II-VI compound semiconductors. In one embodiment, the upper substrate 101 is made of silicon. In one embodiment, the upper substrate 101 is made of polyimide. Typically, the upper substrate 101 is transparent and made of glass or polymer. The upper substrate 101 used in this application may have a thickness of several microns to several millimeters.

[0051] The upper electrode 105 can be any number of equilateral triangular metal electrodes having the dimensions of the maximum outer perimeter area. The equilateral triangular metal electrodes are electrically isolated from one another, spaced apart in both rows and columns. The side lengths of these triangular electrodes can typically be on the order of approximately 1 nm to 1 cm, but may be larger.

[0052] In one embodiment, the upper electrode 105 may be formed inside the upper substrate 101 by conventional lithography, etching, and deposition processes. For example, a photoresist layer may first be formed on the upper substrate 101 and then exposed to form a pattern of triangular openings. For example, an anisotropic etching such as reactive ion etching (RIE) may then be performed, using the patterned photoresist layer as an etching mask to form triangular openings on the upper substrate 101. The triangular openings are then filled with a conductive material such as gold, silver, nickel, copper, tungsten, aluminum, or an alloy thereof to provide the upper electrode 105 (and / or any upper terminal pad). The surface of the structure may be planarized using a planarization process such as chemical mechanical polishing (CMP). After planarization, the upper surface of the upper electrode 105 is coplanar with the upper surface of the upper substrate 101.

[0053] In another embodiment, the upper electrode 105 may be formed on the upper substrate 101 by blanket deposition of a conductive material and then lithographic etching of the conductive material. For example, the conductive material may first be blanket-deposited on the upper substrate 101 using conventional deposition processes such as chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma-enhanced vapor deposition (PECVD), or atomic layer deposition (ALD). A photoresist layer is then formed on the conductive material and exposed to form openings therein. The exposed conductive material is then removed through the openings using a RIE to form the upper electrode 105 using the patterned photoresist layer as an etching mask. Subsequently, the patterned photoresist layer may be removed, for example, by ashing. The upper surface of the upper electrode 105 is thus positioned above the upper surface of the upper substrate 101.

[0054] In yet another embodiment, the upper electrode 105 may be formed on the upper substrate 101 by a resist that is exposed and patterned by lithography in the intended non-electrode 105 region, a metal seed layer is then blanket-deposited, the blanket seed layer is plated with metal, and the patterned resist having the seed layer and plated metal is lifted off in the region between the intended electrodes 105. The upper surface of the upper electrode 105 is thus positioned above the upper surface of the upper substrate 101.

[0055] When the upper electrode 105 is formed on the upper substrate 101, an insulating layer may be deposited on the upper substrate 101 after the formation of the upper electrode 105 to embed the upper electrode 105. The insulating layer may include a dielectric material such as silicon dioxide, silicon nitride, or an organic silicate glass with a low dielectric constant (low k); the term "low k" refers to a dielectric material having a dielectric constant lower than that of silicon dioxide. The insulating layer can be formed, for example, by CVD, PECVD, or spin coating. The insulating layer is optional and may be omitted in some embodiments of this application.

[0056] In embodiments, the method includes the step of forming external conductive signal lines or external conductive traces 110 connected to each electrode along a first direction, for example, a column (or row) direction. In embodiments, the external conductive trace lines 110 extend in a vertical direction (e.g., the y-axis direction) connecting the electrodes of each column. The external conductive lines connect the electrodes along the column to terminal pads (not shown) that provide external connections of the electrodes to an external capacitance sensing / detection circuit and / or image processing circuit.

[0057] In one embodiment of an upper electrode substrate 101 including a plurality of upper electrodes 105 surrounded by a passivation layer, each of the upper electrodes 105 is electrically connected to an external conductive wire (e.g., connected to an upper terminal pad) via a connecting via structure 205.

[0058] Each through-via structure is an interconnect via 205 connected to an interconnect conductive wire or external conductive trace 110, which electrically connects the interconnect via 205 to the corresponding terminal pad 114 for external connection at the edge of the substrate. In one embodiment, the insulating substrate 101 is on a silicon or glass handler, and the side without the handler can be advanced where the external conductive trace 110 and upper terminal pad 114 of the interconnect via structure 205 can be formed. A second handler is just completed and attached to the side, and the first handler is removed from the other side of the insulating substrate 101 when a passivation layer is formed after the metal electrode 105. The second handler is removed here. The conductive material for the trace 110 may be a metal such as copper, tungsten, aluminum, or an alloy. The conductive material compatible with coupling with the terminal pad 114 may be a metal such as copper, tin, gold, or an alloy. The conductive material of the through-via 205, whose acceptable coefficient of thermal expansion is, may be a metal such as tungsten, copper, or an alloy. The trace 110, terminal pad 114, and through via 205 are formed using normal, well-established microelectronics manufacturing procedures. It should be noted that the interconnecting conductive wires or trace 110 and upper terminal pads may also be formed by screen printing or stencil printing techniques of suitable conductive paste material. In this case, the upper surfaces of the interconnecting conductive wires or trace 110 and upper terminal pads are positioned above the upper surface of the insulating layer.

[0059] In another embodiment, after the upper substrate 101 is formed, the interconnection structure 205 (and upper terminal pads) may be formed by a dual damascene process known in the art. In this case, the upper surfaces of the interconnection conductive wires or traces 110 and the upper terminal pads are coplanar with the upper surface of the insulating substrate 101.

[0060] In embodiments of this specification, the method for forming a 2D array of planar bottom triangular electrodes 125 on a bottom substrate 121 is the same as the method for forming upper electrodes 105 on an upper substrate. However, the formed external conductive wires 130 connect to each electrode along a second direction, for example, a row (or column) direction. In embodiments, the external conductive wires 130 extend horizontally (for example, in the x-axis direction) connecting the electrodes of each row. The external conductive wires 130 connect the electrodes along the row to terminal pads (not shown) that provide external connections of the electrodes to an external capacitance sensing / detection circuit and / or image processing circuit.

[0061] Each exemplary capacitive sensor array 100, 200, 300 can be formed by assembling an upper substrate 101 across a bottom electrode substrate 121 having upper electrodes 105 and bottom electrodes 125 facing each other. The upper electrodes 105 and bottom electrodes 125 are intersected, i.e., directly aligned, to form a plurality of microcapacitive units. The relative dimensions of the upper substrate 101 and the bottom substrate 121 are selected as follows, resulting in the upper terminal pad (not shown) being positioned beyond the edge of the bottom substrate 121 along the y-direction, meaning the upper terminal pad is not covered by the bottom substrate 121, while the bottom terminal pad is positioned beyond the edge of the upper substrate 101 along the x-direction, meaning the bottom terminal pad is not covered by the upper substrate 101.

[0062] The upper electrode substrate 101 is separated from the lower electrode substrate 121 by a spacer such as a ring or gasket 161. The gasket 161 sets the distance "d" between the upper electrode substrate 101 and the lower electrode substrate 121. The height of the gasket 161 can be adjusted to obtain the best measurement resolution. In the example, the height of the gasket 161 may be 1 nm to 1 cm. The gasket 161 is formed along the periphery of either the upper substrate 101 or the lower electrode substrate 121 to separate the upper electrode substrate 101 and the lower electrode substrate 121. The gasket 161 may consist of multiple individual spacers arranged around the periphery of one of the upper electrode substrate 101 and the lower electrode substrate 121, and any number of spacers can be used to improve the mounting stability of the upper electrode substrate 101. The gasket 161 can be deposited on one of the electrode substrates 101, 121 before the upper electrode substrate 101 and the lower electrode substrate 121 are assembled.

[0063] The gasket 161 can be made from a rigid material having high tensile strength. In one embodiment, the gasket 161 may be made from a ceramic. Exemplary ceramics include, but are not limited to, TiO2, Ta2O5, BaTiO3, SrTiO3, PbZrTiO3, LiNbO3, PbMgTiO3, and PbMgNbO3. In another embodiment, the gasket 161 may be made from a polymer. Exemplary polymers include, but are not limited to, epoxy, polyimide, polyurethane, parylene, polysulfone, polysulfide, benzylcyclobutenes (BCB), nylon, polyvinylidene fluoride (PVDF), and phenol. In yet another embodiment, the gasket 161 can be made of an insulator commonly used in microelectronics manufacturing, such as various oxides or nitrides, or of an insulating coated conductor, such as copper or aluminum, which has been passivated by a layer of oxide or nitride.

[0064] The gasket 161 can be formed by methods known in the art. In one embodiment, the gasket 161 can be formed from a pair of solder materials having a first gasket (not shown) formed on one of the upper electrode substrate 101 and the bottom electrode substrate 121, and a second gasket (not shown) formed on the other of the upper electrode substrate 101 and the bottom electrode substrate 121. Exemplary solder materials that can be used in this application include, but are not limited to, tin / copper, tin / silver (high silver concentration), tin / gold, SAC (tin with low aluminum and copper content), and nickel with SAC. During the assembly process, once the first and second gaskets are mated, the solder material is reflowed to provide the gasket 161. In another embodiment, the gasket 161 can be formed via a mechanical interlock. For example, a double-knob gasket (not shown) may be formed on one of the upper electrode substrate 101 and the lower electrode plate 121, and a single-knob gasket may be formed on one of the upper electrode substrate 101 and the lower electrode substrate 121. During mating, the upper electrode substrate 101 and the lower electrode substrate 121 are joined by the tensioned double-knob gasket being forcibly locked over the single-knob gasket. In yet another embodiment, the gasket 161 may be provided by simply forming an epoxy gasket on the lower electrode substrate 121.

[0065] The gasket 161 may also be used to ensure that the fluid is sealed inside the opening or channel after the liquid medium containing the specific analyte has been introduced into the channel. Although not shown, the upper electrode substrate 101 may also include one or more through-holes (not shown) through which the liquid medium can be introduced into the channel.

[0066] Figure 11 shows a microcapacitive, multi-channel sensing circuit and instrumentation system 400 for detecting and monitoring the movement of nanoparticle material or biological organisms according to one embodiment. As shown in Figure 11, the microcapacitive sensing circuit and data acquisition system 455, which includes a circuit configured to detect the presence and / or movement of the analyte, is operably connected to an assembled microcapacitor sensor, such as the assembled microcapacitor sensor array structure 100 in the exemplary embodiment of Figure 4, the assembled microcapacitor sensor sensing structure 200 in Figure 6, or the assembled microcapacitor sensor sensing structure 300 in Figure 9.

[0067] In the system 400 of Figure 11, the capacitance detection circuit and data acquisition system 455 are operably connected to the assembled microcapacitor sensor structure 100 using electrical circuit wire connections 402 and 404, which are connected to both ends of each external conductive signal line 110 and 130, respectively, via terminal connections such as terminal pads 114. The individual electrical leads 402 are connected to each individual conductive signal line or external conductive trace line 110 that contacts the triangular planar electrode via their respective through-via connections along each row of electrodes 105. Similarly, each individual electrical lead 404 is connected to each individual conductive signal line or external conductive trace line 130 that contacts the triangular planar electrode via their respective through-via connections along each row of electrodes 125.

[0068] The capacitance detection circuit 455 includes a detection and measurement circuit for detecting an electrical signal having a characteristic (e.g., voltage), which is used to detect changes in the dielectric constant of the medium caused by the presence of an analyte (particle or biological organism) in the medium, detected between a pair of consecutive upper planar electrodes 105 and an aligned bottom electrode 125, and to record these voltage changes over time. In one embodiment, a computer or image processing unit 465 is connected to the data acquisition unit 455 for data / image processing.

[0069] In one embodiment, as shown in Figure 11, the capacitance sensing circuit 455 is capable of performing capacitance measurements of one electrode against all other electrodes in a time series. The capacitance sensing circuit typically includes several subcircuits (not shown) coupled to the upper and lower terminal pads 114 via I / O pins (not shown). Thus, the upper electrode 105 and the lower electrode 125 can be grouped in different ways via the subcircuits. When measuring capacitance, the capacitance sensing circuit 455 can provide alternating current (AC) or direct current (DC) excitation. DC excitation may include a path to ground (GND). The integrated sensing circuit allows for connecting the upper electrode 105 and the lower electrode 125 with fewer leads, thereby improving the signal-to-noise ratio, reducing the number of inputs / outputs, and eliminating the need to use external circuitry to perform the same function.

[0070] In one embodiment, the capacitance sensing circuit includes subcircuits (not shown) that enable connection to a first set of bottom terminal pads 114 located at the first end of a conductive wire connected to the bottom electrode 125; a second subcircuit that enables connection to a second set of bottom terminal pads 114 located at the second end of the wire connected to the bottom electrode 125, opposite to the first end; a third subcircuit that enables connection to a first set of top terminal pads 114 located at the first end of the top electrode 105; and a fourth subcircuit that enables connection to a second set of top terminal pads 114 located at the second end of the top electrode 105. Such an arrangement provides very high flexibility in data acquisition by independently acquiring signals from the subcircuits. In this case, the number of capacitance measurements that can be performed independently is n / 2 for the total number of n electrodes.

[0071] Although not shown, each subcircuit may include a pair of multiplexers (mux) connected to the instrumentation amplifier. In one embodiment, the instrumentation amplifier may be a capacitance sensing amplifier for AC or DC differential capacitance sensing, or for two-lead (+ / -) or three-lead (+ / - / GND) hookups. In another embodiment, the instrumentation amplifier may be a current amplifier for quasi-static capacitance measurement or resistance measurement.

[0072] In the case of sensor operation using any of the microcapacitive sensor embodiments shown in Figures 4, 6, and 9, an analytical medium (for example, a fluid such as water or another liquid, or a liquid mixture such as an emulsion (water in which oil droplets are dispersed) or a mixture of immiscible liquid chemicals) containing the object to be analyzed (particles or living organisms) whose movement is tracked is introduced between the upper substrate 101 and the bottom substrate 121. For example, living organisms such as bacteria or viruses move in the liquid medium, and as they move between a pair of aligned electrodes (for example, electrodes 105 and 125), the dielectric constant between the two aligned electrodes changes. In Figure 11, in order to detect or track the movement of particles or living organisms and perform 2D detection, it is necessary for the processor 455 to detect the change in dielectric constant in multiple pairs of two or more consecutive pairs of two aligned electrodes 105 and 125. In other words, in the case of 2D detection, when a particle or living organism crosses a continuous pair of aligned electrodes 105, 125 in the medium, the multi-channel detection circuit and instrumentation system 400 detect a change in dielectric constant as a signal transmitted through signal lines 402, 404 in each of the continuous pairs of aligned electrodes 105, 125.

[0073] In the case of multi-channel 2D detection, a quasi-static magnetic field distribution is assumed, i.e., the signal frequency is sufficiently low, and as a result, the displacement current can be ignored. Poisson's equation determines the electric field distribution inside the imaging domain, and it is further assumed that the operating wavelength is much larger than any of the line dimensions of the imaging domain. The sensitivity matrix of the capacitive sensor is a capacitance variation map with respect to a set of discrete dielectric perturbations in the imaging domain.

[0074] The capacitance of the sensor depends on the dielectric constant of the medium between the pair of capacitively aligned sensor electrodes 105, 125. The actual capacitance (Ca) due to the liquid sample exists in series with the capacitance (Cs) of the 2D glass (or other material) slide.

[0075] Therefore, the total capacitance (Ct) of the sensor can be expressed according to Equation (1) as follows: Ct = C a C s / (C a + C s ) (1)

[0076] The capacitance on the glass (or other material) side depends on the dielectric material of the glass (or other material) and is a constant. On the other hand, the actual capacitance due to the liquid sample is proportional to the dielectric constants of the liquid and solid filling the volume between the two glass (or other material) slides.

[0077] The effective dielectric constant (ε a ) of the host liquid and the nanoparticles depends on the two volume ratios according to Equation (2) as follows: ε a = (V l ε l + V p ε p ) / V t (2)

[0078] Here, V l , V p , V t are the volumes of the liquid, nanoparticles, and the total volume, respectively, and ε l , ε p are the dielectric constants of the liquid and nanoparticles, respectively.

[0079] When the sensor electrode is in direct contact with the liquid sample (without the 2D glass (or other material) slide), the total capacitance follows Equation (3) as follows: C t = C a = ε a A / d (3)

[0080] Here, A and d are the electrode area and separation distance d, respectively.

[0081] Furthermore, in the case of multi-channel 2D detection, the analyte particles are expected to be affected by Brownian motion. Thus, as shown in equation 4) below:

number

[0082] Here, D is defined as the diffusion constant, A is the active capacitance electrode area, and n a This is the number of analyte molecules (nanoparticles) per unit volume. When using a single sensor, it is possible to detect a signal due to the presence of tens to hundreds of molecules. However, with normal dilution (n a In a mixture of ~small (~small) elements, it takes an unacceptably long time (Δt ~ large) for the analyte molecule to transition from one electrode area to another (so that motion can be detected). In aspects of the present invention, this problem is overcome by employing an array of spatially dispersed small electrodes operating in parallel. In the case of an electrode array of n / 2 electrode pairs operating in parallel, the corresponding detection time is scaled down by approximately 2 / n, and sensitivity is maintained for the time required to collect information from all array elements. In the case of n / 2 electrode pairs, there are n connections and n detection circuits (or alternatively, n / m if the multiplicity of detection circuits is m).

[0083] Scanning the capacitance sensor array 100 is thus based on the differential capacitance measurement of the intersecting upper electrode 105 and bottom electrode 125 pairs. Since the upper electrode 105 and bottom electrode 125 are separated by a spacer or gasket 161, the system of the present invention enables 3D image detection from edge to edge of the upper electrode substrate 101 and bottom electrode plate 121. In addition, the effect of parasitic capacitance is also eliminated by measuring the differential capacitance between the aligned and intersecting upper electrode 105 and bottom electrode 125 pairs.

[0084] As shown in Figure 11, multiple detected electrical signal characteristics based on differential capacitance values ​​are processed in system 400, and the movement of the analyte over time is identified, imaged, or tracked by a display imaging device 465 operably connected to a data acquisition circuit 455, thereby enabling reconstruction and display of the detected particles or biological analytes. The detected movement of the analyte and corresponding exemplary reconstructed images are shown as images 470 and 471, respectively.

[0085] A measurement process using the exemplary capacitance sensor arrays 100, 200, 300 of the present application for monitoring the movement of an analyte using the system shown in Figure 11 in operation may include introducing a solution or medium containing the analyte into a channel defined by a peripheral gasket 161. In one embodiment, the solution or medium can be introduced into the channel through a through-hole under vacuum. For a self-assembling material solution, it is introduced by flowing the solution into one through-hole and out through another through-hole (not shown). Alternatively, a self-assembling material solution can be introduced by exposing the through-hole to vacuum and then backfilling the through-hole with the solution or medium. In yet another embodiment, a self-assembling material solution can be introduced into the cavity before the upper electrode substrate 101 is assembled to the bottom electrode substrate 121. A capacitance measurement is then performed across the electrode pairs of the entire capacitance sensor array (100, 200, or 300). Capacitance can be measured between neighboring electrodes on the same electrode plate (e.g., either the upper electrode substrate 101 or the lower electrode substrate 121), or between the upper and lower electrodes 105, 125 at the intersection of the upper electrode substrate 101 and the lower electrode substrate 121. The capacitance changes are then monitored across the entire capacitance sensor array. By recording the capacitance of electrode pairs over time, a 2D capacitance map of the entire capacitance sensor array can be generated. Any capacitance change between electrode pairs indicates the presence of the analyte. The capacitance of electrode pairs across the entire capacitance sensor array is recorded over time. In one embodiment, for example, the dynamics of biological movement can be obtained from capacitance changes between electrode pairs at different locations.

[0086] Thus, aspects of the present invention provide a microsensor applicable to monitoring the movement of very small particles (<200 nm nanoparticles) by imaging fluid changes in dielectric constant through a simplified 2D (in-plane) arrangement of electrode sensors. This includes tracking the movement of molecules or biomarkers. With such a simplified 2D arrangement of electrodes, only n / 2 independently performed capacitance measurements are required to image the movement.

[0087] Although this application has been specifically shown and described with respect to various embodiments thereof, those skilled in the art will understand that the aforementioned and other variations in form and detail can be made without departing from the scope of this application. Accordingly, this application is not intended to be limited to the exact forms and details described and illustrated, but is intended to be included in the appended claims.

Claims

1. A first two-dimensional (2D) array of non-contact conductive electrodes, each molded on a first electrode surface according to the maximum outer peripheral area ratio, and The device comprises a second 2D array of non-contact conductive electrodes, each of which is molded on the second electrode surface according to the maximum outer peripheral area ratio, The first electrode surface and the second electrode surface overlap and are parallel, and each conductive electrode of the first 2D array and the corresponding conductive electrode of the second 2D array are aligned and separated to define a channel between them, so that the substance to be analyzed can be detected between the first electrode surface and the second electrode surface. Microcapacitive sensor.

2. The microcapacitance sensor according to claim 1, further comprising one or more dielectric materials between the first electrode surface and the second electrode surface.

3. A first electrical insulating substrate on which the first 2D array of non-contact conductive electrodes of the first electrode surface is formed; A second electrically insulating substrate on which the second 2D array of non-contact conductive electrodes of the second electrode surface is formed; and A sealing structure formed on the peripheral surfaces of the first and second electrical insulating substrates, which connects the first electrical insulating substrate to the second electrical insulating substrate and achieves separation for defining the channel. The microcapacitive sensor according to claim 1, further comprising:

4. The microcapacitive sensor according to claim 3, wherein the insulating substrate includes one or more of glass, plastic, or an organic printed circuit board.

5. The microcapacitive sensor according to claim 1, wherein the non-contact conductive electrodes on the first electrode surface and the second electrode surface each include a transparent conductive film.

6. The microcapacitive sensor according to claim 1, wherein the molded conductive electrode having the maximum outer surface area ratio is triangular.

7. Each single conductive signal line in contact with each of the non-contact conductive electrodes along each single row or each single column of the first 2D array of non-contact conductive electrodes; and Each single conductive signal line in contact with each of the non-contact conductive electrodes along each single column or each single row of the second 2D array of non-contact conductive electrodes The microcapacitive sensor according to claim 3, further comprising:

8. The first electrical insulating substrate has a first surface on which the first electrode surface of the first 2D array of non-contact conductive electrodes is formed, and a second surface on which each of the single conductive signal lines is formed, and the structure further: Each conductive through-via structure has a first end that contacts each conductive electrode formed on the first surface, and a second end that contacts each single conductive signal line formed on the second surface. A microcapacitive sensor according to claim 7, including the above.

9. The second electrical insulating substrate has a first surface on which the second electrode surface of the second 2D array of non-contact conductive electrodes is formed, and a second surface on which each of the single conductive signal lines is formed, and the structure further: Each conductive through-via structure has a first end that contacts each conductive electrode formed on the first surface, and a second end that contacts each single conductive signal line formed on the second surface. A microcapacitive sensor according to claim 7, including the above.

10. Each first single conductive signal line in contact with a plurality of the non-contact conductive electrodes along each single row or each single column of the first 2D array of non-contact conductive electrodes, and each second single conductive signal line in contact with the remaining plurality of the non-contact conductive electrodes along the same single row or each single column of the first 2D array of non-contact conductive electrodes; and Each first single conductive signal line contacts a plurality of the non-contact conductive electrodes along each single column or each single row of the second 2D array of non-contact conductive electrodes, and each second single conductive signal line contacts the remaining plurality of the non-contact conductive electrodes along the same single column or each single row of the first 2D array of non-contact conductive electrodes. The microcapacitive sensor according to claim 3, further comprising:

11. Each set of multiple conductive signal lines in contact with each of the non-contact conductive electrodes along each single row or each single column of the first 2D array of non-contact conductive electrodes; and Each set of multiple conductive signal lines in contact with each of the non-contact conductive electrodes along each single column or each single row of the second 2D array of non-contact conductive electrodes The microcapacitive sensor according to claim 3, further comprising:

12. The microcapacitance sensor according to claim 3, wherein each of the single conductive signal lines in contact with each of the non-contact conductive electrodes of the first 2D array and each of the single conductive signal lines in contact with each of the non-contact conductive electrodes of the second 2D array are further connected to a processing circuit for detecting the movement of the substance to be analyzed between the first electrode surface and the second electrode surface, the processing circuit measuring the change in capacitance between any aligned pair of conductive electrodes of the first 2D array and the corresponding aligned conductive electrodes of the second 2D array.

13. The microcapacitance sensor according to claim 12, wherein the first planar electrode and the second planar electrode generate n / 2 independent capacitance measurements for a total of n electrodes.

14. A system for detecting a substance to be analyzed in a medium, wherein the system is: A first two-dimensional (2D) array of non-contact conductive electrodes, each shaped on a first electrode surface according to its maximum outer peripheral area ratio; and The second electrode surface has a second 2D array of non-contact conductive electrodes, each of which is molded according to the maximum outer peripheral area ratio. The first electrode surface and the second electrode surface overlap and are parallel, and each conductive electrode of the first 2D array and the corresponding conductive electrode of the second 2D array are aligned and separated to define a channel between them so that the substance to be analyzed can be detected between the first electrode surface and the second electrode surface, and further: One or more conductive signal lines in contact with each of the non-contact conductive electrodes along each single row or each single column of the first 2D array of non-contact conductive electrodes; and Each of the one or more conductive signal lines in contact with each of the non-contact conductive electrodes along each single column or each single row of the second 2D array of non-contact conductive electrodes; A microcapacitive sensor having; A sensing circuit is connected to each of the one or more conductive signal lines that contact each of the non-contact conductive electrodes of the first 2D array, and further connected to each of the one or more conductive signal lines that contact each of the non-contact conductive electrodes of the second 2D array, and is adapted to perform capacitance measurements between any aligned pair of electrodes via the channel. A system equipped with these features.

15. The system according to claim 14, further comprising a processor connected to the detection circuit for constructing a motion image of the substance to be analyzed in the channel from changes in volume measurement values.

16. The system according to claim 15, wherein the detection circuit is adapted to vary the voltage amplitude, frequency, waveform shape, timing between the waveform shapes, and the order in which the electrodes are addressed.

17. Steps include providing a first insulating substrate; A step of forming a two-dimensional (2D) array of first conductive electrodes on the surface of the first insulating substrate, each electrode being formed according to its maximum outer perimeter area ratio and spaced apart from one another; A step of forming conductive signal lines on opposing surfaces of the first insulating substrate, such that each conductive signal line is connected to one or more of the first capacitor electrodes along each of the rows of the 2D array by via connections formed through the first insulating substrate; Steps include providing a second insulating substrate; A step of forming a two-dimensional (2D) array of second conductive electrodes on the surface of the second insulating substrate, each electrode being formed according to its maximum outer perimeter area ratio and spaced apart from one another; The steps of forming conductive signal lines on opposing surfaces of the second insulating substrate, such that each conductive signal line is connected to one or more of the second capacitor electrodes along each row of the 2D array by via connections formed through the second insulating substrate; and The step of joining the first insulating substrate and the second insulating substrate using an insulating material such that the first conductor electrode of the first 2D array of capacitor electrodes is aligned with the corresponding second conductor electrode of the second 2D array and separated to define a channel between them. A method for manufacturing a microcapacitive sensor that includes the following features.

18. The method according to claim 17, wherein the step of forming each conductive signal line on the opposing surfaces of the first insulating substrate further comprises the step of forming a plurality of conductive signal lines corresponding to each row of the first electrodes of the 2D array, each of the plurality of conductive signal lines corresponding to each row is connected to one or more of the first capacitor electrodes along each row of the 2D array by via connections formed through the first insulating substrate.

19. The method according to claim 17, wherein each of the first electrode and the second electrode is triangular.

20. The method according to claim 17, wherein the first conductive electrode and the second conductive electrode are adapted such that n / 2 independent capacitance measurements are generated for a total of n electrodes.

Images