The present invention relates to a chip assembly, and particularly relates to an electronic element used for implantation into a living tissue.
Among the patients with vision deterioration, some patients choose to implant retinal prosthesis to improve their vision. At present, commercial retinal prosthesis is expensive and low in the pixel, and the improvement in the quality of life of the patients is limited. In view of this, many companies and academic research units have begun to actively invest in improving the retinal prosthesis microsystem.
For example, U.S. patent Ser. No. 10/760,961, U.S. Pat. Nos. 8,530,265, 8,954,156, 9,114,004, 9,155,881, 9,731,130, etc. disclose that the retinal prosthesis is a chip implanting in a living tissue. In some patents, the chip uses a semiconductor process to manufacture a microelectrode, a photosensor, and other circuits on a silicon substrate, even including a processor and a driver. It can be expected that the material of the chip is relatively hard; and in view of circuit design and complex manufacturing process, the appearance of the chip is difficult to be processed into an ideal shape. In summary, the chip is likely to cause tissue damage when implanted into the living tissue.
The present invention relates to a chip assembly, and in particular to a chip assembly for implantation into a living tissue, which can reduce or avoid damage after the chip assembly, is implanted into the living tissue.
The present invention provides a chip assembly for implantation into a living tissue, comprising: an electronic element, which is defined to form a first contour, and the first contour comprises at least one sharp edge exposed outside; and a buffer material with biocompatibility, which covers the sharp edge and blocks the sharp edge to avoid damage to the living tissue.
The present invention also provides a retinal prosthesis assembly, comprising: a retinal prosthesis chip, which comprises a plurality of light sensing assemblies receiving light, a plurality of microelectrodes, and a circuit coupled to the light sensing assemblies and the microelectrodes. The circuit drives the microelectrodes to provide nerve cells at least one stimulus to perceive an image of the light captured by the light sensing assemblies, wherein the light sensing assemblies, the microelectrodes and the circuit are integrated in a semiconductor device, which comprises a silicon substrate carrying the microelectrodes; an encapsulation layer which at least partially covers the retinal prosthesis chip to protect the retinal prosthesis chip; and a buffer material with biocompatibility covering at least one sharp edge of the retinal prosthesis chip and blocking the sharp edge to avoid damage to the eyeball tissue.
First, the terms used in the description of various embodiments are only for the purpose of describing specific examples, and are not intended to be limiting. Unless the context clearly indicates otherwise, or does not deliberately limit the quantity of the assembly, the singular forms “a”, “an” and “the” used herein also include plural forms. On the other hand, the terms “comprising” and “including” are intended to be included, meaning that there may be additional assemblies other than the listed assemblies.
When an assembly is expressed as being “connected” or “coupled” to another assembly, the assembly can be connected or coupled to the other assembly directly or through an intermediate assembly; additionally, it should be understood that the description order of various embodiments should not be explained as implying that the operations or steps must be dependent on the order, and alternative embodiments may use the order different from the order described herein to perform the steps, operations, methods, etc.
The present invention provides an implantable chip assembly for implantation into a living tissue. The implantable chip assembly comprises an electronic element and a biocompatible buffer material. The electronic element is formed with a first contour, and the first contour comprises at least one exposed sharp edge. The biocompatible buffer material is formed with a second contour, and the second contour is composed of a plurality of flexible planes and a plurality of blunt edges connected between the flexible planes. In an embodiment, the first contour comprises a plurality of planes, and the sharp edge is formed between the planes.
As a buffer structure, the biocompatible buffer material can relieve the damage on the living tissue caused by physical compression, contact puncture or scratches generated by the hard material of the electronic element and the edges, corners on the appearance or other sharp structures. Further, any allergy or rejection situation of cell tissue to the implant is reduced. Therefore, the implantable chip assembly can be applied to various semiconductor devices that require long-term contact with human tissues, such as a subcutaneous chip, a drug release chip, a nerve stimulation chip, an artificial electronic ear, an artificial retina and other biomedical chips.
The following takes the retinal prosthesis as an example to illustrate the specific structure of the implantable chip assembly. Age-related macular degeneration (AN/ID) and retinitis pigmentosa (RP) are the main causes of blindness. The patients lose their ability of producing visual signals due to the degeneration of photoreceptor cells in the retina. However, considering that the bipolar cells and ganglion cells on the retina of the patient still retain partial functions, the retinal prosthesis can be implanted to generate electrical stimulation signals to stimulate these nerve cells to produce visual signals, so the degraded photoreceptor cells can be replaced.
Referring to
In general, the retinal prosthesis chip usually comprises a plurality of electronic elements, and the plurality of electronic elements is usually made from hard materials and has sharp edges. Therefore, it is known that the retinal prosthesis chip is prone to generate allergy or rejection reaction with human tissues after implanted, and is also prone to damage the human tissues. Although there are a multilayer structure usually arranged at the periphery of the retinal prosthesis chip based on the consideration of the biocompatibility and encapsulation, the multilayer structure must still have sufficient hardness to maintain the structure of the retinal prosthesis and provide sufficient supporting force. For the soft tissue in the eye, the hardness of the multilayer structure is too high to cause friction with the tissue cells during implantation, which causes the wear of the tissue cells and is not beneficial to long-term implantation.
The semiconductor device S comprises a silicon substrate 14; and the circuit 13 is formed over the silicon substrate 14. In this embodiment, the semiconductor device S comprises a plurality of pixel units 40 formed on the silicon substrate 14. Each pixel unit 40 comprises the light sensing assembly 11, the microelectrode 12, and a signal processing and drive unit 41. Further, each pixel unit 40 comprises an intermediate layer 42, a first barrier layer 43, a second barrier layer 44, a guard ring 45, and a conductive layer 46. The intermediate layer 42 is arranged among the microelectrodes 12, the light sensing assemblies 11, and the signal processing and drive unit 41. The intermediate layer 42 may be an oxide layer, such as silicon dioxide (SiO2). The encapsulation layer 20 at least partially covers the retinal prosthesis chip 10 to protect the retinal prosthesis chip 10. Specifically, the encapsulation layer 20 is made from a flexible material. The buffer material 30 covers at least one sharp edge of the retinal prosthesis chip 10 and blocks the sharp edge to avoid damage to the eyeball tissue. Referring to
In an embodiment, the buffer material 30 is selected from polyimide, polydimethylsiloxane (PDMS), parylene, liquid crystal polymer and other biocompatible materials. Further, in different embodiments, the buffer material 30 may be formed as an integral structure with elasticity. After being stretched, the buffer material 30 is sleeved to the edge of the retinal prosthesis chip 10; and the buffer material 30 may also include a clamping structure to be fastened to the retinal prosthesis chip 10 in a buckling manner; or the buffer material 30 may also include an adhesive layer to be fixed on the retinal prosthesis chip 10.
As to the application of the retinal prosthesis, the electrical stimulation is transmitted to nerve cells through the electrode array, and thus a neuron-to-electrode distance between the electrode array and nerve cells needs to be required. Therefore, the appearance structure of the retinal prosthesis chip 10 and the microelectrodes 12 needs to be considered accordingly. Besides, if it applied to implanting in the living tissues other than retina, similar requirements will also be raised. Here, only the implantation of the retina is taken as an example.
Further, the retinal prosthesis chip 10 is bent to a curvature conforming to the shape of the human eyeball. In an embodiment, the silicon substrate 14 is thinned to have a thickness that can be bent to conform to the shape of the human eyeball, as shown in
Referring to
A first edge E1 is defined between the upper surface S1 and the periphery S3, a second edge E2 is defined between the lower surface S2 and the periphery S3, and side walls 52 of the cutout channels 50 together with the upper surface S1 and the lower surface S2 separately define a third edge E3 and a fourth edge E4. The sharp edge is formed on at least one of the first edge E1, the second edge E2, the third edge E3, and the fourth edge E4.
In the above embodiments, in an unbending state, protrude ends 40A of the pixel units 40 or sharp ends of the microelectrodes (not shown in figures) are distributed based on an imaginary plane, as shown in
In another embodiment, the silicon substrate 14 is not bent, but a flat substrate is adopted, and the height of the pixel units 40 (the microelectrodes) is manufactured to be non-equal height. Namely, the protrude ends 40A of the pixel units 40 (the sharp ends of the microelectrodes) are directly distributed in a quasi-spherical geometry to conform to the shape of the human eyeball, so that the neuron-to-electrode distance can be achieved between the pixel units 40 (the microelectrode) and the nerve cells without bending the device, as shown in
Different embodiments of the buffer material 30 covering the retinal prosthesis chip 10 are described below. For the convenience of description, the retinal prosthesis chip 10 covered with the encapsulation layer 20 is described as a retinal prosthesis device 10A as follows.
According to an embodiment of the present invention, taking the contour of the retinal prosthesis chip 10 as an example, the retinal prosthesis chip 10 comprises a plurality of flat surfaces, a plurality of curved surfaces, or a combination of a plurality of flat surfaces and curved surfaces. As illustrated in
In an embodiment, the hardness of the buffer material 30 is less than that of the retinal prosthesis chip 10, and is preferably an elastomer or a soft material, which can withstand high elastic deformation. For example, the buffer material 30 comprises polyimide, polydimethylsiloxane (PDMS), parylene, liquid crystal polymer or any combination of the above materials.
In an embodiment, as shown in
In another embodiment, as shown in
The buffer material 30 is defined to form a second contour C2. In the embodiment of
After the retinal prosthesis device 10A is implanted, the microelectrodes contact the retina of the human body, and accordingly the retina generates a pushing pressure to the retinal prosthesis device 10A. Thus, the arrangement of the buffer material 30 can relieve the problem that the retina or other tissues are hurt by the structure of the retinal prosthesis device 10A due to said pushing pressure. The above is only an example. In actual use, the configuration structure of the buffer material 30 is selected according to the implanted position of the implantable chip assembly, so that the buffer material 30 can fit the human tissue and avoid the damage of the electronic element to the human tissue.
Further, if the retinal prosthesis chip 10 with the structure of
In another embodiment, the electronic element is the electrical connecting portion 92 in
Referring to
In the embodiment of
In another embodiment, it provides a method of implanting a retinal prosthesis assembly in an epiretinal region of an eye, comprising the following steps of providing a first incision in sclera; providing a second incision in chorioidea; providing a third incision in retinal; inserting a guide element into the first incision, the second incision and the third incision to reach a position in the epiretinal region by sliding, wherein the guide element is provided with a guide surface; and introducing the retinal prosthesis assembly into the position of the epiretinal region along the guide surface of the guide element. In detail, the retinal prosthesis assembly comprises a retinal prosthesis chip; a biocompatible layer covering the retinal prosthesis chip to protect the retinal prosthesis chip; and a biocompatible buffer material, which covers at least one sharp edge of the retinal prosthesis chip and blocks the sharp edge to avoid damage to the eyeball tissue.
In the present invention, the buffer material 30 is not limited to a flat shape, and can be adjusted according to the specific structure of the human tissue, so that the buffer material 30 has an uneven surface to closely fit with the irregular tissue surface of the human body, and it is possible to improve the transmission efficiency of the signal and reduce the problem of assembly dropping thereof. The above is only an example. In actual use, the configuration structure of the buffer member is selected according to the implanted position of the implantable chip assembly, so that the buffer member can fit with the human tissue to reduce the gap between the electronic element and the buffer material, so as to increase the implantation stability and service life of the retinal prosthesis.
In summary, the implantable chip assembly of the present invention includes a buffer material coated on the electronic element such as the retina chip or the electrical connection portion. The buffer member is made from a biocompatible material, and the hardness of the buffer member is much less than that of the biocompatible encapsulation layer on the electronic element. After the implantable chip is implanted into the human body, the buffer member contacts and is fixed with tissue cells of the human body, so that the electronic element and the tissue cells are separated from each other to reduce side effects such as allergies, rejection or abrasion, further improve the treatment effect and prolong the service life of the implantable electronic chip. The buffer member has a plurality of different forms can be matched with the electronic element with various types and different structures for use. The buffer member can fit with surface of the tissue to be implanted, fix the electronic element, and achieve an optimal treatment effect.
Number | Date | Country | |
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62913305 | Oct 2019 | US |