A nerve stimulator and a method for manufacturing the same

Abstract

The present invention relates to the field of medical devices, and more particularly to a nerve stimulator and a manufacturing method thereof. The nerve stimulator includes a glass substrate, and a plurality of metal pillars are disposed on the substrate. The metal pillars form a stimulation part on one side of the substrate, and the density of the metal pillars is greater than 15 Pin / mm<supgt;2< / supgt;. The stimulation part in this nerve stimulator has a high density and good stimulation effect. Its manufacturing method is to first cut out an array of high-density metal pillars using a metal substrate, then fill it with glass, and finally make it through double-sided thinning. This manufacturing method has a novel process and a unique way, overcoming the defect that it is difficult to manufacture high-density nerve stimulation electrodes using other substrates such as ceramics in the traditional way.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and more specifically to a nerve stimulator and a manufacturing method thereof. Background Art

[0002] As an important tool in the treatment of neurological diseases, microelectrode stimulators have attracted more and more extensive attention and have become an important current research direction. In existing retinal microelectrode stimulators, the stimulating electrodes generally adopt flexible MEMS technology to integrally form the stimulating electrodes, connecting wires, and pads for flip-chip welding with a ceramic substrate. However, the flexible microelectrode wiring is generally connected one by one from the stimulating electrodes to the outside of the eyeball. When the number of stimulating electrodes is too large, the number of wirings also increases, and a large number of wirings will cause an increase in the diameter of the outgoing cable, resulting in a larger postoperative trauma.

[0003] There are also some stimulating electrodes made of rigid materials. The stimulating electrodes are made by drilling holes in the substrate and then embedding stimulating micro needles in the holes. It is generally very difficult to process a stimulating electrode array with a density exceeding 5Pin / mm 2 using such rigid material-made stimulating electrodes.

[0004] In medical treatment, the greater the density of the stimulating electrodes, the better the stimulating effect can be obtained on a smaller substrate. However, how to fabricate a high-density stimulating electrode array has always been a difficult problem in the industry. Summary of the Invention

[0005] In order to solve the above defects such as too small density of the stimulating electrodes and poor stimulating effect, the present invention provides a brand-new nerve stimulator and a manufacturing method thereof. The nerve stimulator in the present invention can fabricate a high-density metal stimulating array on the substrate and can connect a chip on the substrate to avoid the problem of a large number of wirings to the outside of the eyeball, increasing the surgical trauma. The specific solutions are as follows:

[0006] First of all, the present invention protects a nerve stimulator, including a substrate, on which a plurality of metal columns are provided. The metal columns form a stimulating part on one side of the substrate. The substrate is made of glass material, and a pad structure made of metal material is also provided on the glass substrate. In the present invention, the substrate is made of a brand-new glass material, and the stimulating electrodes are also made of metal material. The materials of this nerve stimulator are very different from those of traditional stimulating electrodes, which is convenient for processing.

[0007] Preferably, the density of the metal columns is greater than 15Pin / mm 2 and the greater the density, the better the stimulating effect. The specific density of the metal columns can be adjusted according to actual needs. Since it is processed by cutting metal, the adjustable range of its density is very large.

[0008] Preferably, the height of the stimulation part is 1 μm - 100 μm.

[0009] Preferably, the stimulation part is in a conical column shape.

[0010] Preferably, the pad structure is arranged on the substrate on the side opposite to the stimulation part. The pad structure is generally multiple and can be set according to actual wiring requirements.

[0011] Preferably, a processing chip is further connected to the substrate, and the processing chip and the substrate are connected together by flip chip bonding. The processing chip can be directly connected to the stimulation electrode array. In this way, when wiring to the outside of the eyeball, it is not necessary to draw out connection lines from each stimulation electrode. It is only necessary to connect the chip inside the eyeball to the processing chip outside the eyeball.

[0012] The present invention also protects a manufacturing method of the high-density nerve stimulator, which is specifically as follows:

[0013] A manufacturing method of a nerve stimulator, characterized by comprising the following steps:

[0014] S1: Provide a metal substrate and cut out a plurality of metal columns on the metal substrate;

[0015] S2: Fill the plurality of metal columns cut out on the metal substrate with glass so that all the cut-out metal columns are covered with glass;

[0016] S3: Thinning both sides of the metal substrate subjected to glass melting and casting, thinning the glass covering layer on the cutting surface of the metal substrate until the metal columns are exposed, and thinning and removing the metal substrate on the other side of the metal substrate until the glass base surface of the casting is completely exposed;

[0017] S4: Process one side so that the metal columns in the glass substrate form a stimulation part on the glass plane, and integrally form a stimulation electrode with a glass substrate.

[0018] Preferably, the cutting method in the step 1 is laser cutting or mechanical cutting.

[0019] Preferably, the metal columns cut out in the step 1 are arranged in an array, and the array shape can be changed according to specific stimulation requirements.

[0020] Preferably, a pad structure for wiring is also cut out in the step 1.

[0021] Preferably, the metal substrate in the step 1 is made of a biocompatible metal material such as titanium, platinum, iridium, tantalum, gold, or their alloys.

[0022] Preferably, the thermal expansion coefficient of the filled glass matches that of the metal substrate.

[0023] Preferably, the thickness of the metal substrate is between 0.3 mm and 1.5 mm, the depth of the cut metal columns is 200 μm to 1000 μm, and the diameter or side length of the cut metal columns is 50 μm to 150 μm.

[0024] Preferably, in the step S2, the specific method of embedding the metal columns into the glass is as follows:

[0025] A. Select a glass substrate and heat it until its material softens;

[0026] B. Press and embed the side with metal columns of the metal substrate with several cut metal columns into the softened glass substrate so that the metal columns are completely wrapped by the glass substrate;

[0027] C. Cool and form.

[0028] Preferably, in the step S2, the specific method of embedding the metal columns into the glass is as follows:

[0029] A. Heat the glass to a molten state of a melt;

[0030] B. Pour the molten glass on the side with metal columns of the metal substrate so that the liquid glass covers all the metal columns;

[0031] C. Cool and form.

[0032] Preferably, in the step S2, the specific method of filling the metal columns with glass is as follows:

[0033] A. Fill the side with cut metal columns of the metal substrate with glass powder;

[0034] B. Heat the metal substrate and the glass powder on it so that the glass powder becomes molten and forms a molten glass layer on the metal substrate.

[0035] C. Cool and form.

[0036] Advantages of the present invention: The nerve stimulator in the present invention uses a glass substrate and a metal stimulating microelectrode. The density of the microelectrode is high and the treatment effect is good. At the same time, the nerve stimulating electrode in the present invention uses a method of cutting a metal substrate, filling a glass layer, and then thinning and removing the metal layer to form a stimulating electrode, which can manufacture a stimulating electrode array with ultra-high density. This manufacturing method has a novel process and a unique method, overcoming the defect that it is difficult to manufacture a high-density nerve stimulating electrode using other substrates such as ceramics in the traditional way. Description of the Drawings

[0037] Figure 1Side view of the nerve stimulator in the present invention;

[0038] Figure 2 Top view of the nerve stimulator in the present invention;

[0039] Figure 3 Flow chart of the manufacturing method of the nerve stimulator in the present invention;

[0040] Figure 4 Flow chart of the manufacturing method of the nerve stimulator in the present invention.

[0041] Where 1 is the glass substrate, 2 is the metal column, 3 is the stimulation part, 4 is the pad structure, and 5 is the processing chip. Detailed implementation mode

[0042] For the convenience of understanding the present invention, its principle is further elaborated below with reference to the accompanying drawings:

[0043] The present invention first discloses a nerve stimulator, which includes a substrate made of glass material. A plurality of metal columns are arranged on the substrate. One side of the metal column forms a stimulation part for stimulating human tissues.

[0044] A pad structure made of metal material is also arranged on the glass substrate. The pad structure is generally used to connect with a chip to control the stimulation electrode. During use, since the pad structure needs to be connected with the outside for signals, the pad structure is generally arranged on the substrate on the side opposite to the stimulation part, so as to avoid interference with the stimulation part during wiring or encapsulation, and at the same time avoid the signal connection part contacting with body fluid for a long time, thereby increasing its reliability.

[0045] Generally, for a nerve stimulator made of a ceramic substrate, the density of its microelectrodes is difficult to exceed 5 Pin / mm 2 , in the present invention, in order to achieve a better stimulation effect, the density of the cut metal columns is greater than 15 Pin / mm 2 .

[0046] The stimulation part formed by the metal columns protruding from the glass substrate is generally arranged in an array, and its shape can be changed according to actual needs. The height of the stimulation part is 1 - 100 um, and the stimulation part is generally in a conical column shape.

[0047] As another aspect of the present invention, a manufacturing method of a nerve stimulator is also protected. Using this manufacturing method, the above nerve stimulator with high-density stimulation electrodes can be manufactured, which is specifically as follows:

[0048] A manufacturing method of a nerve stimulator includes the following steps:

[0049] Step 1: Provide a metal substrate and cut a number of metal posts on the metal substrate;

[0050] This cutting method can be carried out by laser or mechanically. The cut metal posts are arranged in an array, and generally a pad structure will also be cut out during the cutting.

[0051] Step 2:

[0052] Perform glass filling on the cut metal posts, fill the glass on the metal posts so that all the cut metal posts are covered by the glass;

[0053] Step 3: After the filled glass layer cools and forms, perform double-sided thinning on the metal substrate filled with glass, thin the glass covering layer on the cutting surface of the metal substrate until the metal posts are exposed, and thin the other side of the metal substrate until the entire poured glass base surface is exposed. In this way, the metal layer can be completely removed, leaving a nerve stimulator with a glass substrate and integrally formed with multiple stimulating electrodes on it.

[0054] S4: After completing the above steps, perform further processing on one side. Using the cutting method, remove the glass substrate around the metal posts on one side so that the metal posts in the glass substrate protrude from the glass plane to form a stimulating part, and integrally form a stimulating electrode with a glass substrate.

[0055] In the above Step 2, the specific method of performing glass melting and pouring can have the following three embodiments:

[0056] Embodiment 1:

[0057] Step 1: Select a glass substrate and heat it until its material softens;

[0058] Step 2: Extrude and embed the side of the metal substrate with the cut metal posts into the softened glass substrate so that the metal posts are completely wrapped by the glass substrate;

[0059] Step 3: Cool and form.

[0060] Embodiment 2:

[0061] Step 1: Heat the glass to a molten state;

[0062] Step 2: Pour the molten glass on the side of the metal substrate with the metal posts so that the liquid glass covers all the metal posts;

[0063] Step 3: Cool and form.

[0064] Embodiment 3:

[0065] Step 1: Cut out metal posts on the metal substrate and fill one side with glass powder;

[0066] Step 2: Heat the metal substrate and the glass powder on it so that the glass powder precipitates in a molten state on the metal substrate to form a molten glass layer.

[0067] Step 3: Cool and form.

[0068] After the above steps, the glass generally needs to be further heated and extruded to reduce the gap between it and the metal posts.

[0069] Since this nerve stimulator needs to be implanted into the body and has relatively high requirements for the biocompatibility of the materials used, the metal substrate processed into the metal post and pad structure is generally made of biocompatible metal materials such as titanium, platinum, iridium, tantalum, gold, or their alloys.

[0070] The thickness of the metal substrate is generally between 0.3 mm and 1.5 mm, which can ensure the length of the cut-out metal posts. At the same time, during the subsequent double-sided thinning process, the processing efficiency will not be reduced due to the too thick metal layer. Also, to ensure the thickness of the glass substrate and the stimulation length of the stimulation part, the depth of the cut-out metal posts is generally 200 μm - 1000 μm, and the diameter or side length of the cut-out metal posts is 50 μm - 150 μm, and the specific values can vary according to actual needs.

[0071] During the subsequent operation process, since the nerve stimulator needs to be signal-connected or connected to a chip, the substrate needs to be heated. To avoid forming a gap between the glass substrate and the metal posts due to heating, the thermal expansion coefficient of the molten-cast glass needs to match that of the metal substrate.

[0072] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the present invention. It should be noted that any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are within the protection scope of the present invention.

Claims

1. A manufacturing method of an implantable nerve stimulator, characterized in that, It includes the following steps: S1: Provide a metal substrate, and cut a number of metal posts on the first surface of the metal substrate; S2: Fill glass into the number of metal posts cut on the first surface of the metal substrate so that all the cut metal posts are covered by the glass; S3: Thin the second surface of the metal substrate filled with glass, which is opposite to the first surface, until the entire glass base surface is exposed, and then thin the glass covering layer on the first surface until the metal posts are exposed; S4: Process the first surface to make the metal posts in the glass substrate protrude on the glass plane to form a stimulating part, and integrally form a stimulating electrode with a glass substrate, so that the glass substrate can be connected to the processing chip on the second surface by flip-chip bonding; Among them, the density of the metal column is greater than 15 Pin / mm 2 ; and The thermal expansion coefficient of the filled glass matches the thermal expansion coefficient of the metal substrate.

2. The method according to claim 1, characterized in that The cutting method in the step S1 is laser cutting or mechanical cutting.

3. The method according to claim 1, wherein The metal posts cut in the step S1 are arranged in an array.

4. The method according to claim 1, characterized in that, The metal substrate in the step S1 is made of a biocompatible metal material such as titanium, platinum, iridium, tantalum, gold, or their alloys.

5. The method according to claim 1, wherein The thickness of the metal substrate is between 0.3 mm and 1.5 mm, the depth of the cut metal posts is 200 μm to 1000 μm, and the diameter or side length of the cut metal posts is 50 μm to 150 μm.

6. The method according to claim 1, characterized in that, In the step S2, the specific method for filling glass into the metal posts is as follows: A. Select a glass substrate and heat it until its material softens; B. Press and embed the metal post side of the metal substrate with a number of cut metal posts into the softened glass substrate so that the metal posts are completely wrapped by the glass substrate; C. Cool and form.

7. The method according to claim 1, characterized in that, In the step S2, the specific method for filling glass into the metal posts is as follows: A. Heat the glass to a molten state; B. Pour the molten glass on the metal post side of the metal substrate so that the liquid glass covers all the metal posts; C. Cool and form.

8. The method according to claim 1, wherein In the step S2, the specific method for filling glass into the metal posts is as follows: A. Fill glass powder on the metal post side of the metal substrate; B. Heat the metal substrate and the glass powder on it so that the glass powder becomes molten to form a molten glass layer on the metal substrate; C. Cool and form.

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