TWI549653B - Probe array and manufacturing method thereof - Google Patents

Description

Probe array and manufacturing method thereof

The present invention provides a probe array and a method of fabricating the same, and more particularly to a probe array and a method of fabricating the same that can be used for human body signal detection.

In recent years, the society has moved toward an aging trend, and health problems of high age have gradually emerged, thus highlighting the importance of biomedical technology. For the measurement and signal acquisition of human body signals, conventional techniques are mostly explored by in vitro measurement and invasive or implantable methods. The extracorporeal measurement is applied to the measuring electrode, coated with a layer of conductive adhesive and attached to the skin to form a wet probe. Although conductive adhesive can improve the interface conductivity, it will damage the skin after the conductive adhesive is dried, and it is impossible to measure for a long time. Invasive or implantable measurement methods, regardless of signal strength and waveform reproducibility, are superior to in vitro measurement probes, but the size of the probe used in this method needs to be carefully planned, because the probe system directly invades. In the human skin, the design must refer to international relevant regulations.

Conventional techniques have utilized microelectromechanical techniques to produce barbed dry brainwave electrodes. The purpose of the barbed shape is to measure the brain wave, the probe can be fixed in the skin, and the probe is prevented from puncturing the skin to the dermis layer, causing the subject to feel pain. Therefore, the height of the probe is designed to be 81 μm and the width is 12-20 μm and fabricated array probes. However, the length of the brain wave electrode is too short to be used for brain wave detection, and the manufacturing cost is high. The prior art also uses a fiber laser plus The method of fabricating array red copper probes has a high processing speed and low processing heat, and the workpiece is not easily deformed. Therefore, the finished product has better dimensional accuracy, but the cost of the equipment required is relatively high. After the laser processing probe is developed and processed, it is actually used for brain wave measurement. The research confirms that for the detection of brain wave signals, the long-term measurement is successful, and the dry electrode and the commercially available wet electrode have the waveform coincidence rate. Quite high. In addition, the use of fine wire cutting EDM technology, cutting high aspect ratio fine probes in tungsten carbide materials, for high aspect ratio fine structure detection, such as 3D-IC circuit detection. In the production process, the piezoelectric ceramic material (Piezoelectric ceramic material) is used to assist the fine wire cutting discharge processing method with high-frequency vibration, which can help slag discharge and reduce the occurrence of secondary discharge during processing. .

However, the above-mentioned conventional technologies still have the disadvantages of requiring expensive equipment costs, environmental problems with corrosive pollution, or low processing efficiency, or limited to the use of bismuth-based materials.

In view of the above problems, the present invention provides a probe array comprising a substrate and at least one probe by spiral discharge machining in a micro-discharge machining mode. The substrate has an upper surface, and the probe has a tip end portion and is integrally formed on the upper surface of the substrate. Wherein, the tip end of the probe has an outer diameter of between 30 and 50 μm , and the length of the probe is between 110 μm and 350 μm . The arithmetic mean roughness of the side surface of the probe was Ra 2.9 μm .

The invention further provides a method for manufacturing a probe array based on the spiral discharge machining of the micro-discharge machining method, comprising the steps of: (S1) preparing a first substrate and a second substrate; (S2) at the first base Processing the upper surface of one of the materials to form an array of micropores; (S3) electrically discharging the second substrate by using the first substrate having the array of micropores as an electrode; and (S4) cutting through the discharge The second substrate is processed to form an array of probes having a plurality of probes. Each of the probes has a tip end portion having an outer diameter of between 30 and 50 μm and a length of each probe between 110 μm and 350 μm .

Compared with the prior art, the present invention provides a probe array and a manufacturing method thereof based on the spiral discharge machining of the micro-discharge machining method, and performs rapid fabrication of the probe. Through precision electrical discharge machining, precise metal removal is achieved and probe arrays can be quickly fabricated. Although the surface of the needle body forms a continuous rough discharge pit, resulting in uneven surface, the surface property can provide sufficient friction of the needle body to the brain cortex tissue, making the probe difficult to fall off from the detected cortical tissue. There is no need to apply conductive paste. In this way, a clear human signal can be obtained.

1‧‧‧ probe array

12‧‧‧ probe

14‧‧‧Substrate

20‧‧‧First substrate

22‧‧‧Array micropores

30‧‧‧Second substrate

A‧‧‧First movement direction

B‧‧‧Second movement direction

C‧‧‧ Third movement direction

D‧‧‧ bottom outer diameter

E‧‧‧Processing electrode

G‧‧‧discharge gap

L‧‧‧ length

P‧‧‧ reduction (total forming capacity)

R‧‧‧ bottom rounded corner

S‧‧‧ shaking amount

T1‧‧‧ substrate upper surface

T2‧‧‧ first substrate upper surface

d‧‧‧The outer diameter of the tip

R‧‧‧ tip round corner

Figure 1 and Figure 2 are electron micrographs of the probe array of the present invention.

Figure 3 is a schematic diagram showing the structure of a probe of one of the probe arrays of the present invention.

FIG. 4 and FIG. 5 are respectively schematic diagrams showing the processing operation of one of the probe array manufacturing methods of the present invention.

6A and 6B are schematic views showing processing parameters of the probe array manufacturing method of the present invention.

This description is only for the purpose of illustrating the essential elements of the invention, and is only intended to illustrate the possible embodiments of the invention, but the description of the specification should not limit the scope of the technical nature of the claimed invention. The present invention is not limited to the specific methods, procedures, functions, or means unless the scope of the invention is specifically excluded.

In addition, it should be understood that the present invention is merely a possible embodiment of the present invention, and any method, process, or function similar or equivalent to the device or system described in the present specification may be used in the practice or testing of the present invention. Or means. All technical and scientific terms used in the specification have the same meaning as commonly understood by those skilled in the art to which the invention pertains, unless otherwise defined. The present description is merely an example method, process, and related materials. However, in the actual use of the present invention, any methods and means similar or equivalent to those described in the specification can be used.

Furthermore, one or more of the numbers mentioned in the specification include the number itself. It should be understood that the present disclosure discloses certain methods and processes for performing the disclosed functions. There are many structures related to the disclosed structures that perform the same functions, and the above structures generally achieve the same result.

Please refer to FIG. 1 to FIG. 3 . FIG. 1 to FIG. 2 are electron micrographs of the probe array of the present invention. Figure 3 is a schematic diagram showing the structure of a probe of one of the probe arrays of the present invention. The present invention provides a probe array 1 comprising a substrate 10 and at least one probe 12. The substrate 10 has an upper surface T1, and the probe 12 has a tip end portion and is integrally formed on the upper surface T1 of the substrate 10.

Wherein, the outer diameter d of the tip end portion of the probe is between 30 and 50 μm , and the length L of the probe is between 110 μm and 350 μm . In an embodiment of the present invention, when the probe for detecting a human body signal is used, the definition of the height of the probe 10 is designed in consideration of the shape of the human skin tissue. The human skin is divided into the stratum corneum with a thickness of 5~10 μm from the outside to the inside; the lower epidermis and the dermis layer of 50~100 μm . Therefore, the height of the probe 12 must be greater than 100 μm , so that the probe 12 can pass through. The stratum corneum with extremely high impedance touches the dermis layer with nerves, so the design must have a height of at least 110 μm . However, because the human hair has a relative thickness, the probe 12 does not easily invade into the skin. The height of the probe 12 of the present invention is selected between 110 μm and 350 μm .

Further, the probe 12 of the probe array 1 of the present invention is measured in such a manner as to invade skin tissue, and therefore, the outer diameter of the tip end of the probe 12 must be miniaturized to reduce pain during intrusion. Generally, the outer diameter of the probe tip for human body signal detection is between 30 and 100 μm , and in the present invention, if the outer diameter of the probe 12 is less than 30 μm , the probe is too fine and prone to occur. If the outer diameter of the probe 12 is more than 100 μm , it is easy to cause pain and unfavorable measurement. Therefore, the tip diameter of the tip of the probe 12 is between 30 and 50 μm . The design of the needle 12, and the preferred embodiment, is that the probe 12 has a tip outer diameter of 50 μm .

The arithmetic mean roughness of the side surface of the probe 12 was Ra 2.9 μm . In an embodiment of the present invention, when the probe for human body signal detection is used, in order to avoid applying the conductive adhesive on the probe array, and it is desired to measure the human body signal for a long time, how to enable the probe to be properly fixed The surface of the subject, such as human skin, becomes a major problem. The probe array 1 provided by the present invention utilizes the side surface of the probe 12 so that the side surface of the probe 12 has a roughness so that it can firmly fit the subcutaneous tissue when it invades the subject, and is not easily peeled off. Through experimental investigation, the preferred embodiment of the arithmetic mean roughness of the side surface of the probe 12 of the present invention is Ra 2.9 μm .

Since the intensity of the human body signal varies with the distance between the tip of the probe and the nerve, the probe 12 must be close to the nerve cell to be tested, which is advantageous for obtaining a large human body signal, and the invention is made to reduce the damage to the skin tissue when invading. The pointed cone probe 12 facilitates intrusion into the subcutaneous tissue measurement. In addition, the design of the tapered probe can enhance the strength of the probe 12 itself, and it is not easy to break when the signal is measured. However, in consideration of the pain when the probe 12 invades the skin, the outer diameter of the probe 12 must be smaller than 100 μ m, therefore, the probe 12 of the probe array 1 of the present invention has a bottom outer diameter of 100 μm , and the tip of the preferred embodiment has an outer diameter of 50 μm , so that the probe 12 of the present invention has a cone. The rate is 1/7.

The probe 12 of the probe array 1 of the present invention has a bottom portion in addition to the tip end portion. The rounding design of the probe 12 of the probe array 1 of the present invention is divided into two parts, which are the tip end portion r of the probe 12 and the bottom rounded corner R, respectively, r=2 μ m, and R=50 μm. . The purpose of the tip fillet r design is to reduce the resistance to intrusion into the skin and to avoid discomfort to the subject; the bottom fillet R is designed to enhance the strength of the probe and prevent bending or breakage. The method for extracting the human body signal is to collect the nerve signal of the single probe 12 by a sensor, and then transmit it to a post-processing system by a controller for waveform identification. Therefore, the present invention designs the probes 12 into an array and arranges them equidistantly to avoid different pitches of the probes 12 and affect the signal detection intensity. While the probe 12 of the present invention is designed to have a pitch between 500 μm and 600 μm , the preferred embodiment of the probe 12 pitch is 550 μm .

Referring to FIG. 4 to FIG. 5 , FIG. 4 and FIG. 5 respectively respectively illustrate a processing action of one of the probe array manufacturing methods of the present invention. The invention provides a method for manufacturing a probe array based on a micro-discharge processing method, comprising the steps of: (S1) preparing a first substrate and a second substrate; and (S2) preparing a surface on the first substrate. Processing to form an array of micropores; (S3) electrically discharging the second substrate by using the first substrate having the array of micropores as an electrode; and (S4) cutting the electrically processed portion The two substrates are formed to form an array of probes having a plurality of probes.

Please refer to Figure 4 first. First, the first substrate 20 and the second substrate 30 are prepared in the step (S1); (S2) is processed on the upper surface T2 of the first substrate 20 to form the array micropores 22. Figure 4 and Figure 5 are only used to assist in explaining the machining operation, and the actual machining situation is not shown in proportion. As shown in FIG. 4, a processing electrode E is subjected to spiral discharge machining on the upper surface T2 of the first substrate 20. (Spiral EDM) to process at least one array of microholes 22. The first substrate 20 is a chrome-plated round bar. Spiral EDM consists of three machining operations: a Pecking process in which the machining electrode E follows a first direction of motion A; and a planetary motion in which the machining electrode E follows a second direction of motion B. (Planetary Motion) processing program; and a rotation process of the processing electrode E along a third movement direction C. The first movement direction A is moved up and down, and by the up and down movement of the processing electrode E, a machining fluid can be forced to be exchanged by the suction movement, and the slag is quickly discharged; the machining electrode E is moved along the third movement direction C. The rotation causes the end of the processing electrode E to be uniformly discharged, and the occurrence of the taper hole in the array micropores 22 is reduced, and the array micropores are formed on the first substrate 20. During the manufacturing process, the machining electrode E performs a planetary motion along the second movement direction B, which causes the machining electrode E to generate a machining electrode E shaking amount.

Please refer to FIG. 6A and FIG. 6B. FIG. 6A and FIG. 6B are schematic diagrams showing processing parameters of the probe array manufacturing method of the present invention. The amount of shaking of the processing electrode E can be expressed by Equation 1 and FIG. 6A and FIG. 6B, where S is the amount of shaking; P is the amount of reduction (total forming amount); and G is the discharge gap. By the design of the above parameters, when the machining electrode E performs planetary machining in the second movement direction B to perform electric discharge machining, the discharge residue is caused to be discharged, and the secondary discharge is reduced. Compared with the electric discharge machining without the planetary motion, the machining time is shortened because the discharge residue is caused to be discharged.

S = PG type 1

Referring to FIG. 5, the step (S3) is followed by performing electrical discharge processing on the second substrate 30 with the first substrate 20 having the array micropores 22 as an electrode; and (S4) cutting the second after the electrical discharge machining. Substrate 30 to form probe array 1 having a plurality of probes 12. As shown in FIG. 5, after the steps (S1) and (S2) are completed, the upper surface T2 of the first substrate 20 has at least one array of micropores 22, and the array micropores 22 are arranged by the user. . Next, will be the first The substrate 20 is inverted such that the array micropores 22 of the upper surface T2 face the second substrate 30, and are punctured along the first movement direction A, and the second motion direction B is planetary motion (Planetary Motion) The second substrate 30 is subjected to electrical discharge machining. Wherein, when the processing electrode E moves up and down by the first movement direction A, a machining fluid can be forced to be exchanged by the suction motion, and the slag is quickly discharged; when the machining electrode E performs the planetary motion along the second movement direction B It is possible to cause the discharge residue to be discharged and to reduce the occurrence of secondary discharge. Compared with the electric discharge machining without the planetary motion, the machining time is shortened because the discharge residue is caused to be discharged.

After the step (S3) is completed, the step (S4) may be performed to cut out the portion of the probe array 1 in which the plurality of probes 12 are formed from the second substrate 30. Further, step (S5) is performed: plating a metal layer on the probe array. Alternatively, the step (S5) is performed, and a second metal substrate 30 on which the probe array 1 of the plurality of probes 12 is formed is first plated with a metal layer, and the probe array 1 is cut. Among them, the step (S4) can be performed by means of wire-cut electrical discharge machining, and the purpose of the step (S5) is to improve the conductivity of the probe array 1.

In summary, the present invention provides a probe array and a method of fabricating the same. Forming a first substrate into an electrode having at least one array of micropores by spiral electrical discharge machining, and performing electrical discharge processing on the second substrate to prepare a substrate and at least one probe Probe array. Wherein, the probe has a tip end, the outer diameter of the tip portion is between 30 and 50 μm , and the length of the probe is between 110 μm and 350 μm .

Compared with the prior art, the present invention provides a probe array and a manufacturing method thereof based on the spiral discharge machining of the micro-discharge machining method, and performs rapid fabrication of the probe. Through precision electrical discharge machining, precise metal removal is achieved and probe arrays can be quickly fabricated. Although the surface of the needle body forms a continuous rough discharge pit, resulting in uneven surface, this surface property can provide a needle The body has enough friction on the cortical tissue of the brain to make the probe difficult to fall off from the detected cortical tissue, and it is not necessary to apply conductive adhesive. In this way, a clear human signal can be obtained.

The above description of the preferred embodiments of the present invention is intended to be illustrative of the invention and the scope of the invention. Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and it is to be understood that the invention may be modified and modified without departing from the spirit and scope of the invention. The scope is subject to the definition of the scope of the patent application attached.

1‧‧‧ probe array

12‧‧‧ probe

14‧‧‧Substrate

D‧‧‧ bottom outer diameter

L‧‧‧ length

R‧‧‧ bottom rounded corner

d‧‧‧The outer diameter of the tip

R‧‧‧ tip round corner

Claims (10)

An array of probes comprising: a substrate having an upper surface; and at least one probe integrally formed on the upper surface of the substrate, the probe having a tip portion; wherein The tip end portion of the needle has an outer diameter of between 30 and 50 μm, and the length of the probe is between 110 μm and 350 μm; the probe further has a bottom portion, and the tip end portion of the probe has a tip end The rounded corner is 2 μm. The probe array of claim 1, wherein the probe has a taper of 1/7. The probe array of claim 1, wherein the probe array comprises a plurality of probes, and the adjacent probes have a spacing between 500 μm and 600 μm. The probe array according to claim 1, wherein the side surface of the probe has an arithmetic mean roughness of Ra 2.9 μm. The probe array of claim 1, wherein the bottom of the probe has a bottom rounded corner of 50 μm. A method for manufacturing a probe array, comprising the steps of: (S1) preparing a first substrate and a second substrate; and (S2) processing on an upper surface of the first substrate to form an array of micropores; (S3) electrically discharging the second substrate by using the first substrate having the array of micropores as an electrode; and (S4) cutting the second substrate after the electrical discharge machining to form a plurality Probe array of probes, wherein each probe has a tip end portion having an outer diameter of 30 to Between 50 μm, and the length of each probe is between 110 μm and 350 μm. The manufacturing method according to claim 6, wherein after the step (S4), the method further comprises the step of: (S5) plating a metal layer on the probe array. The manufacturing method according to claim 6, wherein the step (S2) is processed on the upper surface of the first substrate by a spiral discharge machining (Spiral EDM) to form the array micropores. The manufacturing method according to claim 8, wherein the spiral electrical discharge machining (Spiral EDM) includes a processing procedure such as Pecking, Rotation, and Planetary Motion. The manufacturing method according to claim 6, wherein the electric discharge machining of the second substrate in the step (S3) comprises a processing procedure such as Pecking and Planetary Motion.