CN111050461B

CN111050461B - Electronic device and manufacturing method thereof

Info

Publication number: CN111050461B
Application number: CN201811190621.5A
Authority: CN
Inventors: 王涛; 李旭娜; 翟峰; 贾松霖; 程卫高; 任雅磊
Original assignee: Kunshan New Flat Panel Display Technology Center Co Ltd; Kunshan Govisionox Optoelectronics Co Ltd
Current assignee: Kunshan New Flat Panel Display Technology Center Co Ltd; Kunshan Govisionox Optoelectronics Co Ltd
Priority date: 2018-10-12
Filing date: 2018-10-12
Publication date: 2021-01-22
Anticipated expiration: 2038-10-12
Also published as: CN111050461A; WO2020073591A1

Abstract

The invention relates to an electronic device and a manufacturing method thereof. The electronic device includes: a base including a flexible substrate, and a plurality of islands; a plurality of electronic elements provided on the plurality of island-like portions, respectively; and a stretchable conductive wire electrically connected to each of the plurality of electronic components, each stretchable conductive wire partially embedded in the island portion and remaining portions embedded in the flexible substrate and extending along a curved bend in a plane parallel to the flexible substrate; the island has a rigidity greater than that of the flexible substrate. According to the electronic equipment, in the stretching or bending process of the electronic equipment, the flexible substrate generates large elastic deformation and bears large stretching stress. Therefore, the tensile stress borne by the part of the stretchable wire embedded into the flexible substrate is reduced, the stretching performance of the stretchable wire is improved, the stretchable wire is not easy to break, and the stretching performance of the electronic equipment is improved.

Description

Electronic device and manufacturing method thereof

Technical Field

The present invention relates to the field of flexible electronic technologies, and in particular, to an electronic device and a method for manufacturing the same.

Background

Flexible electronics can be generalized to emerging electronic technologies that fabricate organic/inorganic material electronics on flexible/ductile plastic or thin metal substrates to give electronic devices unique flexibility/ductility.

With the continuous development of flexible electronic technology, the application prospects of flexible electronic devices are wider and wider, such as sensor skins of robots, wearable communication devices, body-embeddable or attachable biological devices, stretchable display devices and the like.

However, since the flexible electronic technology is still in the starting stage at present, the electronic device has a defect of poor tensile performance when a reliability test of stretching or bending is performed on the electronic device.

Therefore, how to improve the tensile property of the electronic device is a problem to be solved by those skilled in the art.

Disclosure of Invention

Accordingly, it is desirable to provide an electronic device and a method for manufacturing the same, which can solve the problem of poor tensile performance of the electronic device when the electronic device is subjected to a reliability test of stretching or bending in the related art.

An electronic device, comprising:

the base comprises a flexible substrate and a plurality of island-shaped parts which are arranged on one side of the flexible substrate and are spaced from each other;

a plurality of electronic elements provided on the plurality of island-like portions, respectively; and

a stretchable conductive wire electrically connected to each of the plurality of electronic components, each of the stretchable conductive wires partially embedded in the island and remaining partially embedded in the flexible substrate and extending along a curved bend in a plane parallel to the flexible substrate;

wherein the island has a stiffness greater than a stiffness of the flexible substrate.

Optionally, the island has a first raceway into which a portion of the stretchable wire is embedded;

the flexible substrate is provided with a second wiring groove for embedding the rest part of the stretchable wire;

the first wiring groove and the second wiring groove are communicated with each other to form a wiring channel for the stretchable wire to bend and extend along a curve in a plane.

Optionally, the stretchable wire comprises a wire portion formed of an electrically conductive material;

the substrate has a first side provided with the first and second cabling channels, and a second side opposite the first side;

the wire portion faces the orthographic projection of the second side and falls into the range of the orthographic projection of the first wiring groove and the second wiring groove facing the second side.

Optionally, a dimension of a longitudinal section of the stretchable conductive wire in a direction perpendicular to the flexible substrate is larger than a dimension in a direction parallel to the flexible substrate.

Optionally, a ratio of a dimension of a longitudinal cross section of the stretchable conductive wire in a direction perpendicular to the flexible substrate to a dimension in a direction parallel to the flexible substrate is less than 10.

Optionally, a connection layer is disposed between the stretchable wire and the side wall of each of the first and second routing grooves.

Optionally, the connection layer is a silicon oxide layer.

Optionally, a surface of the stretchable conductive wire away from the second side of the flexible substrate is provided with a protective layer.

Optionally, the protective layer has a plurality of connection openings exposing portions of the wire portions, and the electronic components are electrically connected to the stretchable wires through the corresponding connection openings.

The manufacturing method of the electronic device comprises the following steps:

forming a filling groove extending along a curve on a bearing substrate;

forming a stretchable wire in the filling groove;

forming a plurality of electronic components on the carrier substrate such that the stretchable conductive wires are electrically connected to each of the plurality of electronic components;

arranging a transition substrate on one side of the bearing substrate with the filling groove;

removing part of the bearing substrate to form a plurality of islands for arranging the electronic elements, and exposing the stretchable wires outside the islands;

forming a flexible substrate on the transition substrate to fill regions between the plurality of islands to embed portions of the stretchable conductive wire in the flexible substrate;

and removing the transition substrate.

According to the electronic device and the manufacturing method thereof, the island-shaped part is arranged on the flexible substrate with lower rigidity, the electronic element is arranged on the island-shaped part with higher rigidity, and the stretchable lead is arranged on the flexible substrate and the island-shaped part in an embedded mode, so that the electronic elements are electrically connected. In the stretching or bending process of the electronic equipment: the flexible substrate generates larger elastic deformation and bears larger tensile stress. Therefore, the tensile stress borne by the part of the stretchable wire embedded into the flexible substrate is reduced, the stretching performance of the stretchable wire is improved, and the stretchable wire is not easy to break, so that the stretching performance of the electronic equipment is improved.

Drawings

Fig. 1 is a schematic cross-sectional view illustrating an electronic device according to an embodiment of the invention;

FIG. 2 is a top view of the electronic device shown in FIG. 1;

FIG. 3 is a flowchart illustrating a method of fabricating an electronic device according to an embodiment of the invention;

FIG. 4 is a schematic cross-sectional view of a stretchable wire according to an embodiment of the present invention;

fig. 5 is a flow chart of a method for manufacturing a stretchable conductive wire according to an embodiment of the present invention.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Generally, an electronic device includes a plurality of electronic components, and electrical connection is required between the respective electronic components to achieve transmission of various electrical signals. Therefore, wiring is required between the respective electronic components. However, in the process of stretching or bending, the wires are subjected to tensile stress, so that the wires themselves are easily broken, and the electrical connection between the electronic components is broken, resulting in poor stretching performance of the electronic device. Therefore, it is desirable to provide an electronic device with improved tensile properties.

It should be noted that the electronic device of the present invention is applicable to any device that can be used in a stretchable or bendable environment. For example, robotic skin sensing, stretchable display devices, wearable devices, body-embeddable or attachable biological devices, in-vehicle equipment, and the like.

Hereinafter, an electronic apparatus in an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic cross-sectional view of an electronic device according to an embodiment of the invention; fig. 2 shows a top view of the electronic device in fig. 1.

As shown in fig. 1 and 2, an electronic device according to an embodiment of the invention includes a substrate 10, a stretchable conductive wire 20, and a plurality of electronic elements 30.

The base 10 includes a flexible substrate 12, and a plurality of islands 14 disposed at one side of the flexible substrate 12 and spaced apart from each other. The plurality of electronic components 30 are provided on the plurality of island portions 14, respectively. The stretchable conductive wire 20 is electrically connected to each of the plurality of electronic components 30, each stretchable conductive wire 20 is partially embedded in the island 14, and the remaining portion is embedded in the flexible substrate 12 and extends along a curved bend in a plane parallel to the flexible substrate 12. The island 14 has a stiffness greater than that of the flexible substrate 12.

In the electronic device, the island portion 14 is disposed on the flexible substrate 12 having a relatively low rigidity, the electronic component 30 is disposed on the island portion 14 having a relatively high rigidity, and the stretchable wire 20 is disposed on the flexible substrate 12 and the island portion 14 in an embedded manner, thereby electrically connecting the electronic components 30. During the stretching or bending process of the electronic device, the flexible substrate 12 generates a large elastic deformation and bears a large tensile stress. Thus, the tensile stress borne by the portion of the stretchable conductive wire 20 embedded in the flexible substrate 12 is reduced, and the tensile property of the stretchable conductive wire 20 is improved, so that the stretchable conductive wire 20 is not easily broken, and the tensile property of the electronic device is improved.

In addition, the island portion 14 is not elastically deformed or slightly elastically deformed during the stretching or bending of the electronic device. Thus, the part of the stretchable wire 20 embedded in the island and the electronic element 30 do not bear tensile stress and do not elastically deform, so that the electrical connection between the stretchable wire 20 and the electronic element 30 is stable and does not break, and the stretching performance of the electronic device is further improved.

It should be noted that, in the prior art, the wire is generally designed into an S shape, so that the wire has a certain tensile property. However, the inventors have found that the tensile properties of such a wire having an S-shape are proportional to the radius of curvature of the wire, i.e., the larger the radius of curvature of the wire, the better the tensile properties of the wire, and the less likely it will break. However, the larger the radius of curvature of the wire, the more space it takes up. The wire is limited by the design requirements of lightness, thinness and miniaturization of the electronic equipment, and the arc radius of the wire cannot be designed to be large enough, so that the tensile property of the wire is limited, namely the tensile property of the wire is poor, and the tensile property of the electronic equipment is poor.

The stretchable conductive wire 20 is embedded in the flexible substrate 12 in the present invention. The tensile property of the tensile wires 20 is improved due to the large tensile stress that the flexible substrate 12 undergoes when stretched or bent, so that it is not necessary to increase the tensile property of the tensile wires 20 by increasing the radius of curvature of the tensile wires 20. That is, the curvature radius of the stretchable wire 20 can be properly reduced, and the stretching performance of the stretchable wire 20 cannot meet the requirement of the electronic device, so that the area occupied by the stretchable wire 20 is reduced, and the design requirement of the electronic device for lightness, thinness and miniaturization can be better met. Meanwhile, when the stretchable wires are provided with a plurality of wires, the wires are effectively prevented from being conducted with each other and are not easy to be short-circuited by adopting a mode of embedding the flexible substrate 12.

It should also be noted that the stretchable conductive wire 20 electrically connected to each of the plurality of electronic components 30 may be understood to include one or more of the following forms of electrical connection:

1) two adjacent or non-adjacent electronic components 30 are electrically connected with each other through the stretchable wire 20;

2) a plurality (i.e., two or more) of electronic components 30 are electrically connected to one or more other electronic components 30 via the stretchable wire 20;

3) the electronic component 30 is led out of the substrate 10 by being electrically connected to the stretchable conductive wires 20, facilitating electrical connection with other devices than the substrate 10.

In particular embodiments, the electronic component 30 is a metal and/or semiconductor component, such as an electrode, a chip, a sensor, an OLED (organic electroluminescent diode) display device, a Micro LED display device, and the like.

In an embodiment of the present invention, the island 14 is embedded in one side of the flexible substrate 12. In this manner, the island 14 surrounds the flexible substrate 12. Since the island 14 is more rigid than the flexible substrate 12. The flexible substrate 12 provides better protection for the island 14 during stretching or bending, further avoiding damage to the electronic components disposed on the island 14.

In an embodiment of the invention, the island 14 has a first routing channel 16 in which a portion of the stretchable wire 20 is embedded. The flexible substrate 12 has a second routing channel 18 in which the remainder of the stretchable wire 20 is embedded. The first and

second routing grooves

16, 18 communicate with each other to form a routing channel for the stretchable wire 20 to extend in a curved bend in a plane. As such, during stretching or bending of the electronic device, the island 14 deforms less or hardly, and thus the portion of the stretchable wire 20 embedded in the first routing groove 16 is also subjected to less tensile stress. At the same time, the flexible substrate 12 is subjected to a greater tensile stress, sharing a majority of the tensile stress for the stretchable conductor 20 embedded within the second routing channel 18. Also, the tensile stress experienced by the flexible substrate 12 is less distributed at the side walls of the second routing grooves 18. Therefore, the tensile stress borne by the stretchable wire 20 embedded in the second wiring groove 18 is smaller, and the stretching performance of the stretchable wire 20 is improved, so that the stretching performance of the electronic device is improved.

In some embodiments, the stretchable wire 20 comprises a wire portion formed of an electrically conductive material. Base 10 has a first side 19 provided with first and

second routing channels

16, 18, and a second side opposite first side 19. The orthographic projection of the wire portion toward the second side falls within the range of the orthographic projection of the first and

second routing channels

16, 18 toward the second side.

Therefore, the orthographic projection of the wire part towards the second side falls into the orthographic projection range of the first wire distributing groove 16 and the second wire distributing groove 18 towards the second side, so that the opposite two sides of the wire part embedded in the first wire distributing groove 16 are not provided with parts protruding out of the two side walls of the first wire distributing groove 16, the opposite two sides of the wire part embedded in the second wire distributing groove 18 are not provided with parts protruding out of the two side walls of the second wire distributing groove 18, therefore, the tensile stress received by the wire part embedded in the first wire distributing groove 16 is the stress distributed on the two side walls of the first wire distributing groove 16, and the tensile stress received by the wire part embedded in the second wire distributing groove 18 is the stress distributed on the two side walls of the second wire distributing groove 18. In the stretching or bending process of the electronic device, the two side walls of the first wiring groove 16 have almost no stress distribution, and the two side walls of the second wiring groove 18 have small stress distribution, so that the tensile stress borne by the wire portion is small, and the stretching performance of the electronic device is improved.

It should be noted that, in the prior art, during the stretching process of the S-shaped lead, the arc-shaped concave side of the lead bears the tensile stress, and the arc-shaped convex side of the lead bears the compressive stress. The inventor of the present invention has found that, when the width of the conductive wire (i.e. the vertical distance between the arc-shaped concave side and the arc-shaped convex side of the conductive wire) is wider, the tensile stress and the compressive stress respectively borne by the arc-shaped concave side and the arc-shaped convex side are larger, and the tensile property of the conductive wire is poorer. That is, the tensile properties of the wire are inversely proportional to the width of the wire. However, reducing the width dimension of the conductive line results in an increase in the resistance of the conductive line, which affects the conductive performance.

Based on this, in some embodiments of the present invention, the dimension of the longitudinal cross-section of the stretchable conductive wire 20 in the direction perpendicular to the flexible substrate 12 is larger than the dimension in the direction parallel to the flexible substrate 12.

The dimension of the longitudinal section of the stretchable wire 20 in the direction perpendicular to the flexible substrate 12 is defined as the thickness dimension of the stretchable wire 20, and the dimension of the longitudinal section of the stretchable wire 20 in the direction parallel to the flexible substrate 12 is defined as the width dimension of the stretchable wire 20. Thus, the stretchable wire 20 is designed to have a thickness dimension greater than a width dimension thereof, which reduces the width dimension of the stretchable wire 20, further reduces the tensile stress and the compressive stress on both sides of the stretchable wire 20, and improves the stretching performance of the stretchable wire 20, thereby improving the stretching performance of the electronic device. Meanwhile, the thickness dimension of the stretchable wire 20 is increased, thereby preventing the resistance from increasing due to the decrease in the width of the stretchable wire 20 and ensuring that the resistance of the stretchable wire 20 meets the requirements of electronic devices. Specifically, the stretchable wire 20 has a rectangular longitudinal section.

Optionally, a ratio of a dimension of the longitudinal cross-section of the stretchable conductive wire 20 in a direction perpendicular to the flexible substrate 12 to a dimension in a direction parallel to the flexible substrate 12 is less than 10. Preferably, the ratio of the dimension of the longitudinal section of the stretchable wire 20 in the direction perpendicular to the flexible substrate 12 to the dimension of the width in the direction parallel to the flexible substrate 12 is equal to 5. Thus, the problem that the stretchable conductive wire 20 is too large in thickness and too small in width is avoided, and the difficulty of the process for forming the stretchable conductive wire 20 is increased.

It should be noted that the longitudinal section of the stretchable wire 20 is perpendicular to the extending direction of the stretchable wire 20.

In the embodiment shown in fig. 1, the direction perpendicular to the flexible substrate 12 is a vertical direction, and the direction parallel to the flexible substrate 12 is a horizontal direction.

Alternatively, the flexible substrate 12 may be formed using silicone rubber, a polyurethane-based elastic material, an acrylic elastic material, or the like. The stretchable wire 20 may be formed using any conductive material, such as copper, aluminum, gold, molybdenum, tungsten, titanium, and the like. Preferably, the flexible substrate 12 is formed using Polydimethylsiloxane (PDMS). The tensile leads 20 are formed of copper.

In some embodiments, a connecting layer 40 is provided between the stretchable wire 20 and the sidewalls of both the first and

second routing channels

16, 18. In this manner, the adhesion of the stretchable wire 20 to the side walls of the first and

second routing grooves

16, 18 is increased. Optionally, the material of the connection layer 40 is silicon oxide (SiO)_X). In this manner, adhesion between the stretchable wire 20 and the sidewalls of the first and

second routing grooves

16 and 18 is increased due to good adhesion of silicon oxide.

In some embodiments, a surface of a side of the stretchable conductive wires 20 away from the second side of the flexible substrate 12 may be provided with a protective layer (not shown) covering the stretchable conductive wires. Thus, the stretchable wire is protected.

In one embodiment, the protective layer has a plurality of connection openings exposing portions of the stretchable conductive wires 20, and the electronic components 30 are electrically connected to the stretchable conductive wires through the corresponding connection openings. In this manner, the provision of the connection opening facilitates the electrical connection of the electronic component 30 to the tensile lead 20.

In order to further understand the technical solution of the present invention, an embodiment of the present invention further provides a method for manufacturing an electronic device.

Fig. 3 is a flow chart illustrating a method for manufacturing an electronic device according to an embodiment of the invention.

Referring to fig. 3, a method for manufacturing an electronic device in an embodiment of the invention includes the steps of:

s110: forming a filling groove extending along a curve on a bearing substrate;

specifically, first, a photoresist is coated on a carrier substrate, exposed and developed to form a mask, so as to expose the region where the filling trench needs to be formed. Then, a filling groove is formed on the carrier substrate using an etching process, for example, a dry etching process.

S120: forming a stretchable wire 20 in the filling groove;

specifically, first, a layer of conductive material is formed on the carrier substrate by a vapor deposition or electroplating process to fill the filling groove. Then, a Polishing process, such as a Chemical Mechanical Polishing (CMP) process, is used to remove the conductive material on the surface of the carrier substrate and leave the conductive material filling the grooves to form the stretchable conductive traces 20.

In the embodiment of the present invention, before step S120, the method further includes the steps of: forming a connection layer 40 on the sidewall of the filled trench;

specifically, a layer of link material is deposited on the carrier substrate using a Plasma Enhanced Chemical Vapor Deposition (PECVD) or atomic deposition (ALD) process to form a link layer 40 on the sidewalls of the filled trenches. Preferably, the material of the connection layer 40 may be silicon oxide (SiO)_X)。

It should be noted that the connecting material on the surface of the carrier substrate (i.e., the connecting material other than the connecting material deposited in the filling grooves) can be removed in step S120 by using a polishing process to remove the conductive material on the surface of the carrier substrate.

S130: forming a plurality of electronic components 30 on the carrier substrate such that the stretchable conductive wires 20 are electrically connected to each of the plurality of electronic components 30;

s140: arranging a transition substrate on one side of the bearing substrate with the filling groove;

specifically, the transition substrate may be disposed on the side of the carrier substrate having the filled trench by a zero-time bonding method.

Optionally, the transition substrate is a glass substrate. It is understood that the transition substrate may be a rigid substrate made of other materials, and is not limited herein.

S150: removing a portion of the carrier substrate to form a plurality of islands 14 for disposing the electronic components 30 and expose the stretchable wires 20 outside the islands 14;

specifically, a portion of the carrier substrate on the side of the stretchable conductive wires 20 away from the transition substrate is removed using a chemical mechanical polishing process (CPM) to expose a surface of the side of the stretchable conductive wires 20 away from the transition substrate. It is understood that the connecting material on the side of the stretchable conductive wire away from the transition substrate may also be removed in this step. Then, a photoresist is coated on the side of the carrier substrate away from the transition substrate, and is exposed and developed to form a mask covering the stretchable conductive wires 20 and the area of the carrier substrate corresponding to the electronic element 30. Then, an etching process, such as a dry etching process, is used to remove the carrier substrate that is not covered by the mask.

S160: forming the flexible substrate 12 on the transition substrate to fill the regions between the plurality of islands 14, thereby embedding portions of the stretchable conductive wires 20 in the flexible substrate 12;

specifically, the flexible substrate 12 is formed by coating an elastic material on the side of the transition substrate having the stretchable conductive wires 20.

S170: and removing the transition substrate.

In the embodiment of the present invention, before step S130, the method may further include the steps of: a protective layer covering the stretchable conductive wire 20 is formed on a side of the stretchable conductive wire 20 away from the bottom wall of the filling groove to cover the stretchable conductive wire 20.

In the embodiment, firstly, a photoresist is coated on the side of the carrier substrate having the stretchable conductive wires 20, and is exposed and developed to form a mask to cover the surface area of the carrier substrate and expose the stretchable conductive wires 20. Then, a protective layer material may be deposited on the side of the carrier substrate having the reticle using a Plasma Enhanced Chemical Vapor Deposition (PECVD) or atomic deposition (ALD) process. Finally, the mask is removed to form a protective layer covering the stretchable conductive lines 20.

To facilitate electrical connection of the stretchable conductive wires 20 with the electronic component 30, in some embodiments, a protective layer may be formed to cover the surface of the carrier substrate and portions of the stretchable conductive wires 20. And removing the mask to form a protective layer with a connection opening, wherein the electronic element is electrically connected with the stretchable wire through the connection opening. It is understood that the number of the connection openings may include a plurality for the electrical connection of the plurality of electronic components 30 with the stretchable wire 20.

Fig. 4 is a schematic cross-sectional view illustrating a stretchable wire according to an embodiment of the present invention.

As shown in fig. 4, an embodiment of the invention further provides a stretchable wire, which includes a flexible substrate 100 and a wire portion 200 formed of a conductive material. The wire portion 200 is completely embedded in one side of the flexible substrate 100 and extends along a curve on a plane.

The wire portion 200 is completely embedded in one side of the flexible substrate 100. Therefore, during the stretching process, the flexible substrate 100 is subjected to a large tensile stress, and most of the tensile stress is shared by the wire portions 200. Thus, the tensile stress to which the wire portion 200 is subjected is reduced, and the risk of breakage of the wire portion 200 is reduced, thereby improving the tensile property of the stretchable wire. Further, the curvature radius of the wire portion 200 can be reduced, the space occupied by the stretchable wire can be reduced, and the design requirements of lightness, thinness and miniaturization of the electronic device can be met.

In the embodiment of the present invention, one side of the flexible substrate 100 has an insertion groove 102 for disposing the wire part 200. The wire portion 200 is completely inserted into the insertion groove 102. In this way, when the stretchable wire is stretched, the distribution of the tensile stress borne by the flexible substrate 100 on the sidewall of the embedded groove 102 is small, so that the tensile stress borne by the wire portion 200 is also small, and the stretching performance of the stretchable wire is further improved.

It is understood that, since the wire portion 200 extends along a curve in a plane, the insertion groove 102 also extends along a curve in a plane.

It is also understood that one side of the flexible substrate 100 may have a plurality of insertion grooves 102, and each insertion groove 102 has a wire portion 200 disposed therein. The plurality of lead portions 200 may be connected to each other or not according to actual needs, and are not limited herein.

In an embodiment of the present invention, the flexible substrate 100 includes a first side 104 having an embedded slot 102 and a second side 106 opposite the first side 104. The orthographic projection of the wire portion 200 towards said second side 106 falls within the range of the orthographic projection of the embedded groove 102 towards the second side 106. In this way, since the orthographic projection of the wire portion 200 toward the second side 106 falls within the range of the orthographic projection of the embedded groove 102 toward the second side 106, no part of the wire portion 200 protrudes from the two side walls of the embedded groove 102 on the two opposite sides, the tensile stress applied to the wire portion 200 embedded in the embedded groove 102 is the stress distributed on the two side walls of the embedded groove 102. Since the stress distribution of the two side walls of the embedded groove 102 is small, the tensile stress borne by the wire portion 200 is also small, and the tensile property of the conductive portion 200, that is, the tensile property of the stretchable wire, is further improved.

It should be noted that, in the prior art, during the stretching process of the S-shaped wire, the arc-shaped inner side of the wire is subjected to a tensile stress, and the arc-shaped outer side of the wire is subjected to a compressive stress. The inventor researches and discovers that when the width of the wire is wider, the tensile stress borne by the inner side and the outer side of the arc is larger, and the tensile property of the wire is poorer. That is, the tensile properties of the wire are inversely proportional to the width of the wire. However, reducing the width dimension of the conductive line results in an increase in the resistance of the conductive line, which affects the conductive performance.

Based on this, in the embodiment of the present invention, the size of the longitudinal section of the wire portion 200 in the direction perpendicular to the flexible substrate 100 is larger than the size in the direction parallel to the flexible substrate 100. The dimension of the longitudinal section of the wire portion 200 in the direction perpendicular to the flexible substrate 100 is the thickness dimension of the wire portion 200, and the dimension of the cross section of the wire portion 200 in the direction perpendicular to the flexible substrate 100 is the width dimension of the wire portion 200. Thus, the width dimension of the wire portion 200 is smaller than the thickness dimension, the width dimension of the wire portion 200 is reduced, and the stretching performance of the wire portion 200, i.e., the stretching performance of the stretchable wire, is further improved. Meanwhile, the thickness dimension of the wire portion 200 is increased, thereby ensuring that the cross-sectional area of the wire portion 200 is unchanged or has less variation, and making the resistance of the wire portion 200 unchanged or has less variation. That is, the tensile property of the stretchable wire is improved without increasing the resistance of the stretchable wire. Specifically, the wire portion 200 has a rectangular cross-section.

Alternatively, the ratio of the size of the longitudinal section of the wire portion 200 in the direction perpendicular to the flexible substrate 100 to the size in the direction parallel to the flexible substrate 100 is less than 10. Preferably, the ratio of the dimension of the longitudinal section of the wire portion 200 in the direction perpendicular to the flexible substrate 100 to the dimension of the width in the direction parallel to the flexible substrate 100 is 5. Thus, the excessive thickness and width of the wire portion 200 are avoided, and the difficulty of the process for forming the wire portion 200 is increased.

The longitudinal section of the lead portion 200 is perpendicular to the extending direction of the lead portion 200.

In the embodiment shown in fig. 4, the direction perpendicular to the flexible substrate 100 is a vertical direction, and the direction parallel to the flexible substrate 100 is a horizontal direction.

Alternatively, the flexible substrate 100 may be formed using silicon rubber, polyurethane-based elastic material, acrylic elastic material, or the like. The wire portion 200 may be formed using any conductive material, such as copper, aluminum, gold, molybdenum, tungsten, titanium, and the like. Preferably, the flexible substrate 100 is formed using Polydimethylsiloxane (PDMS). The lead portion 200 is formed of copper. Alternatively, the depth of the insertion groove 102 is 2 μm to 50 μm. The width of the insertion groove 102 is 1 μm to 10 μm.

Alternatively, the wire portion 200 may have an S-shape, a square waveform, a sinusoidal shape, a saw tooth shape, or the like.

Referring to fig. 3, in the embodiment of the invention, a connection layer 300 is disposed between the wire portion 200 and the sidewall of the insertion groove 102, so that the wire portion 200 is attached to the sidewall of the insertion groove 102 through the connection layer 300. As such, the adhesion of the wire portion 200 to the flexible substrate 100 is increased on the one hand. On the other hand, the wire portion 200 is made to be more closely attached to the side wall of the insertion groove 102. Since the flexible substrate 10 is stretched during the stretching process0 is subjected to a large tensile stress, while the side walls of the embedded groove 102 are distributed with a small tensile stress. Therefore, the wire portion 200 is attached to the sidewall of the insertion groove 102 through the connection layer 300, so that the tensile stress applied to the wire portion 200 is further reduced, and the tensile property of the wire portion 200 is improved. Optionally, the material of the connection layer 300 is silicon oxide (SiO)_X). Alternatively, the connection layer 300 may have a thickness of 10nm to 1 μm.

In some embodiments, a surface of the wire portion 200 facing away from the second side 106 of the flexible substrate 100 is provided with a protective layer (not shown) to cover the wire portion 200. Thus, the protective layer provides a good protection for the wire portion 200. Optionally, the material of the protection layer is the same as that of the connection layer 300. Thus, the protective layer and the connection layer 300 can be formed in one process, and the process flow is simplified. Alternatively, the thickness of the protective layer may be 10nm to 1 μm.

In an embodiment, the protective layer has at least two connecting openings (not shown) exposing portions of the wire portions 200, and the connecting openings are used for exposing portions of the wire portions 200 to facilitate electrical connection with corresponding electronic components.

In order to further understand the technical solution of the present invention, an embodiment of the present invention further provides a method for manufacturing a stretchable wire.

Referring to fig. 5, a method for manufacturing a stretchable conductive wire according to an embodiment of the present invention includes:

step S210: forming a filling groove extending along a curve on a bearing substrate;

specifically, first, a photoresist is coated on a carrier substrate, exposed and developed to form a mask, so as to expose the region where the filling trench needs to be formed. Then, an etching process, such as a dry etching process, may be used to form the filled trench on the carrier substrate.

Step S220: filling the filling groove with a conductive material to form a wire portion 200;

specifically, first, a layer of conductive material is formed on the carrier substrate by a vapor deposition or electroplating process to fill the filling groove. Then, a Polishing process, such as a Chemical Mechanical Polishing (CMP) process, is used to remove the conductive material on the surface of the carrier substrate, and the conductive material in the filled trench is remained, so as to form the conductive line portion 200.

Step S230: removing a portion of the carrier substrate to completely expose the wire portion 200;

specifically, a layer of photoresist is coated on the carrier substrate, exposed and developed to form a mask to cover the wire portion 200. Then, an etching process, such as a dry etching process, is used to remove a part of the carrier substrate to completely expose the wire portion 200.

Step S240: forming the flexible substrate 100 on the carrier substrate such that the wire portion 200 is completely embedded in the flexible substrate 100;

specifically, an elastic material is coated on the side of the carrier substrate having the wire portion 200 using a coating process, forming the flexible substrate 100.

Step S250: and removing the rest part of the bearing substrate.

Specifically, the remaining portion of the carrier substrate is removed using a Polishing process, such as a Chemical Mechanical Polishing (CMP) process.

In the embodiment of the present invention, before step S220, the method further includes the steps of: forming a connecting layer 300 on the side wall of the filling groove and forming a protective layer on the bottom wall of the filling groove;

specifically, a layer of link material is deposited on the carrier substrate using a Plasma Enhanced Chemical Vapor Deposition (PECVD) or atomic deposition (ALD) process to form a link layer 300 on the sidewalls of the filled trench and a protective layer on the bottom wall of the filled trench. Optionally, the material of the connection layer 300 and the protection layer is the same, for example: silicon oxide (SiO)_X)。

It should be noted that the connecting material on the surface of the carrier substrate (i.e., the connecting material other than the connecting material deposited in the filling grooves) can be removed in step S220 by using a polishing process to remove the conductive material on the surface of the carrier substrate.

It should be noted that the protective layer may be removed in some embodiments to facilitate electrical connection of the wire portion 200 to other electronic components. In this manner, polishing may be continued to remove the protective layer after the remaining portion of the carrier substrate is removed using the polishing process in step 250.

In other embodiments, the protective layer may not be removed, and may protect the wire portion 200 to prevent the wire portion 200 from directly contacting water, oxygen, and the like in the external environment. Further, to facilitate the electrical connection of the wires with the electronic component 30, a step of: at least two connection openings are formed in the protective layer using an etching process to expose portions of the conductive portion 200 for electrical connection with other devices.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An electronic device, comprising:

wherein the island has a stiffness greater than a stiffness of the flexible substrate;

the dimension of the longitudinal section of the stretchable wire in the direction perpendicular to the flexible substrate is larger than the dimension in the direction parallel to the flexible substrate.

2. The electronic device of claim 1, wherein the island has a first routing channel in which a portion of the stretchable wire is embedded;

3. The electronic device of claim 2, wherein the stretchable wire comprises a wire portion formed of an electrically conductive material;

4. The electronic device of claim 1, wherein the island is embedded in a side of the flexible substrate.

5. The electronic device of claim 1, wherein a ratio of a dimension of a longitudinal cross-section of the stretchable conductive wire in a direction perpendicular to the flexible substrate to a dimension in a direction parallel to the flexible substrate is less than 10.

6. The electronic device of claim 2, wherein a connecting layer is disposed between the stretchable wire and the sidewalls of the first and second cabling channels.

7. The electronic device of claim 6, wherein the connection layer is a silicon oxide layer.

8. An electronic device according to claim 3, wherein a surface of the stretchable conductive wire remote from the second side of the flexible substrate is provided with a protective layer.

9. The electronic device as claimed in claim 8, wherein the protective layer has a plurality of connecting openings exposing portions of the stretchable conductive wires, and the electronic component is electrically connected to the stretchable conductive wires through the corresponding connecting openings.

10. A method of making an electronic device, comprising:

forming a filling groove extending along a curve on a bearing substrate;

forming a stretchable wire in the filling groove;

and removing the transition substrate.