Ultra-flexible electronic device integrated in a vascular stent and applications thereof

Abstract

The present application relates to the technical field of intelligent support, especially to a super flexible electronic device integrated in a blood vessel support and application thereof. The present application provides a super flexible electronic device, comprising a self-expanding blood vessel support, a flexible substrate and an electrode which are sequentially stacked on the surface of the self-expanding blood vessel support; the self-expanding blood vessel support is of a grid structure; the flexible substrate is also of a grid structure, and the flexible substrate covers part of the surface of the grid structure; the electrode is located on the surface of the flexible substrate. The super flexible electronic device has deformation characteristics and does not affect the mechanical properties of the support during the deformation process, and the super flexible electronic device has a signal monitoring function.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent stent, and in particular to a super flexible electronic device integrated in a vascular stent and application thereof. BACKGROUND

[0002] Cardiovascular disease (CVD) has become the main factor endangering people's health. Among them, coronary heart disease is the main direct cause of death. For patients with coronary heart disease, one of the most common and effective treatment methods is to implant a heart stent to restore the myocardial blood supply due to arterial stenosis. During the operation, the doctor will send the stent to the stenosis of the coronary artery through the catheter, and use the balloon expansion technology to make the stent expand radially and adhere to the blood vessel wall. The traditional stent design adopts a physically expandable mesh structure, which mainly functions to support and maintain the restoration of the diseased blood vessel lumen to near normal size, preventing reocclusion.

[0003] There is a new type of intelligent stent at present, which adopts advanced micro-nano processing technology, and its surface inherits the pressure sensor element. In this way, the implanted intelligent stent can not only provide mechanical support, but also can monitor the pressure changes inside the blood vessel in real time, thereby providing more accurate disease assessment and subsequent treatment decision basis for doctors. The stent is wrapped by a layer of poly (p-xylylene), and has passed the viability experiment of human umbilical vein endothelial cells, verifying the biocompatibility. The preparation process is to first make a 2D planar pressure sensor and a stent, and then heat treat the stent to make it self-shrink into a cylindrical shape. Since the stent is integrally and one-time made, it loses the function of expanding through the physical structure of the original stent, and the flexible electronic device existing on the surface of the stent is also in the form of a film, which also limits the function of expanding through the physical structure of the stent. The new stent lacks the function of deformation, and the stent needs to enter the human body in an expanded form, which is contrary to the minimally invasive nature of the existing stent, and the bare stent implanted in the blood vessel is prone to cause restenosis and other problems. SUMMARY

[0004] The present application aims to provide a super flexible electronic device integrated in a vascular stent and application thereof, which has a deformation characteristic and does not affect the mechanical properties of the stent during the deformation process, and at the same time has a signal monitoring function.

[0005] In order to achieve the above-mentioned application purpose, the present application provides the following technical solutions:

[0006] The present application provides a super flexible electronic device, comprising a self-expanding vascular stent, a flexible substrate and an electrode which are sequentially stacked on the surface of the self-expanding vascular stent.

[0007] The self-expanding vascular stent is a mesh structure.

[0008] The flexible substrate is a grid structure, and the flexible substrate covers part of the surface of the grid lines of the grid structure.

[0009] The electrode is located on the surface of the flexible substrate.

[0010] Preferably, the grid shape of the self-expanding vascular stent is a diamond structure.

[0011] Preferably, the material of the flexible substrate is polyimide.

[0012] The grid shape of the flexible substrate is the same as the grid structure of the self-expanding vascular stent, and a plurality of grid structures of the self-expanding vascular stent constitute a grid of the flexible substrate.

[0013] Preferably, the width of the grid line in the flexible substrate is 0.06mm-1mm, and the thickness of the flexible substrate is 10-200μm.

[0014] Preferably, the electrode is further connected with a lead wire.

[0015] Preferably, the electrode comprises a first metal layer and a second metal layer which are sequentially stacked.

[0016] The materials of the first metal layer and the second metal layer are different.

[0017] The application also provides a preparation method of the ultra-flexible electronic device.

[0018] After spin-coating a sacrificial layer and a flexible substrate photoresist on the surface of a silicon wafer, sequentially performing a first exposure, a first development and a rinsing of patterning, a substrate layer is obtained.

[0019] After spin-coating a negative photoresist on the surface of the substrate layer, sequentially performing a second exposure and a second development of patterning, evaporating an electrode layer, removing the sacrificial layer on the surface of the silicon wafer, and attaching the obtained flexible functional layer to the surface of the self-expanding vascular stent, and the flexible substrate covers part of the surface of the grid structure of the self-expanding vascular stent, the ultra-flexible electronic device is obtained.

[0020] Preferably, the flexible substrate photoresist is a polyimide photoresist.

[0021] The spin-coating of the flexible substrate photoresist comprises sequentially performing a first spin-coating, a second spin-coating and a third spin-coating,

[0022] The developing solution used in the first development is cyclopentanone, and the rinsing solution used in the rinsing is PGMEA rinsing solution.

[0023] The first exposure further comprises a soft baking.

[0024] The first exposure further comprises a post-exposure bake;

[0025] The rinsing further comprises a hard bake.

[0026] Preferably, the negative photoresist is RN246 photoresist;

[0027] The second exposure further comprises a soft bake before the second exposure;

[0028] The second exposure further comprises a post-exposure bake after the second exposure.

[0029] The application further provides an application of the super flexible electronic device in the field of intelligent stents.

[0030] The application provides a super flexible electronic device, comprising a self-expanding vascular stent, a flexible substrate and an electrode which are sequentially stacked on the surface of the self-expanding vascular stent; the self-expanding vascular stent is a grid structure; the flexible substrate is also a grid structure, and the flexible substrate covers part of the surface of the grid structure; and the electrode is on the surface of the flexible substrate. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 The figure is a schematic diagram of the planar development of the self-expanding stent described in Example 1;

[0032] Figure 2 The figure is a schematic diagram of the pattern of the flexible substrate layer (a) and the combination of the flexible substrate and the self-expanding stent (b) described in Example 1;

[0033] Figure 3 The figure is a schematic diagram of the shape of the electrode layer described in Example 1;

[0034] Figure 4 The figure is a schematic diagram of the actual development of the super flexible electronic device described in Example 1 (a) and the actual picture after stretching (b);

[0035] Figure 5 The figure is a schematic diagram of the actual development of the super flexible electronic device described in Example 1 (a) and the actual picture after stretching (b);

[0036] Figure 6Physical structure diagram of each patterned flexible substrate layer in the functional layer of the flexible substrate described in Example 1 (a is the physical structure diagram before stretching, b is the physical structure diagram after 120% stretching).

[0037] Figure 7 Physical structure diagram of the structure designed for two electrolytes on each patterned flexible substrate layer in the functional layer of the flexible substrate described in Example 1. DETAILED DESCRIPTION

[0038] The present application provides a super flexible electronic device, comprising a self-expanding vascular stent, a flexible substrate and an electrode which are sequentially stacked on the surface of the self-expanding vascular stent.

[0039] The self-expanding vascular stent is a grid structure.

[0040] The flexible substrate is a grid structure, and the flexible substrate covers part of the surface of the grid structure.

[0041] The electrode is located on the surface of the flexible substrate.

[0042] In the present application, the grid shape of the self-expanding vascular stent is preferably a diamond structure. In the present application, the nominal diameter of the self-expanding vascular stent is preferably 6 mm, the effective length is preferably 20 mm, and the diameter of the metal part is preferably 0.06 mm. In the embodiment of the present application, the model of the self-expanding vascular stent is HC*TDE-6020, which is purchased from Shanghai Xinwei Medical (the schematic diagram of the planar expansion of the self-expanding stent).

[0043] In the present application, the material of the flexible substrate is preferably polyimide. In the present application, the polyimide itself has the advantages of photosensitivity and good metal adhesion, and at the same time, the polyimide is a relatively common flexible material, which has good mechanical properties and microfabrication stability. Compared with PMDS, its elastic modulus is larger, and the metal layer is not easy to break after being attached to the surface of the substrate layer, and the processing technology of the polyimide is also simpler, and the structure strength of the obtained substrate layer is better, and it is not easy to break during stretching. Compared with SU-8 photoresist, the processing process of the polyimide is simpler, the surface of the substrate layer is smoother, and the structure strength is better, and it is not easy to break.

[0044] In the present application, the thickness of the flexible substrate is preferably 10-200, more preferably 5-30 μm, and more preferably 15 μm. In the present application, the flexible substrate with the above thickness can ensure the good structure strength of the substrate layer while avoiding the problem of affecting the natural expansion shape of the stent caused by the too thick substrate layer.

[0045] In the present application, the width of the grid lines in the flexible substrate is preferably 0.06mm-1mm. In the present application, the width of the grid lines at the diamond-shaped bending portions is 0.06mm, and the width of the rest of the grid lines is 1mm. In the present application, the grid shape of the flexible substrate is preferably the same as the grid structure of the self-expandable vascular stent, and several grid structures of the self-expandable vascular stent constitute one grid of the flexible substrate. In an embodiment of the present application, every 9 grid structures of the self-expandable vascular stent constitute one grid of the flexible substrate.

[0046] In the present application, the flexible substrate can be stretched to 125% of the original length, and more preferably to 120% of the original length, and after multiple stretching, the structure of the substrate layer is not damaged. The deformation mode of the substrate layer is consistent with the deformation mode of the self-expandable vascular stent, which is diamond-shaped deformation, so that after being attached to the surface of the self-expandable vascular stent, it can be deformed together with the self-expandable vascular stent.

[0047] In the present application, the electrode is preferably also connected with a lead; the electrode preferably comprises a first metal layer and a second metal layer which are sequentially stacked, and the materials of the first metal layer and the second metal layer are preferably different. In the present application, the first metal layer is preferably a chromium layer, and the second metal layer is preferably a gold layer. In the present application, the thickness of the chromium layer is preferably 10-50nm, and more preferably 20nm; the thickness of the gold layer is preferably 100-300nm, and more preferably 200nm.

[0048] In the present application, two electrodes are preferably arranged on the grid surface of each flexible substrate (as shown in Figure 3 The two electrodes are arranged on the grid surface of the flexible substrate and do not contact each other.

[0049] In the present application, the function of the lead is to connect the electrode with external electronic devices. The sequential stacking of chromium and gold on the electrode is to help the adhesion of gold to the surface of the substrate layer, and gold is more stable in nature and is suitable for use as a surface electrode.

[0050] The present application makes electrodes on the surface of the flexible substrate, and can maintain effectiveness during stretching and bending. Two electrodes are designed and made on each patterned substrate layer, and the resistance value measured from both ends is 36.1kΩ. When the substrate layer is stretched, the overall resistance value does not change significantly, because the flexible substrate uses twisting and rotation instead of stretching and compression at the bending portions during stretching, and the metal part is not stretched and compressed, so the cross-sectional area and length do not change, and therefore the resistance value does not change.

[0051] In the present application, compared with the thin film flexible electronic device, the flexible substrate in the super flexible electronic device of the present application does not affect the natural deformation mode of the self-expandable vascular stent after being attached to the surface of the self-expandable vascular stent, and it has both crimping deformation and stretching deformation modes, and can enter and exit the catheter together with the self-expandable vascular stent.

[0052] The present application also provides a preparation method of the super flexible electronic device described in the above technical solution, comprising the following steps:

[0053] After spin-coating a sacrificial layer and a flexible substrate photoresist on the surface of a silicon wafer, sequentially performing a first exposure, a first development and rinsing, a substrate layer is obtained.

[0054] After spin-coating a negative photoresist on the surface of the substrate layer, sequentially performing a second exposure and a second development, and then evaporating an electrode layer, the sacrificial layer on the surface of the silicon wafer is removed, and the obtained flexible functional layer is attached to the surface of the self-expandable vascular stent, and the flexible substrate covers part of the surface of the grid structure of the self-expandable vascular stent, thereby obtaining the super flexible electronic device.

[0055] In the present application, all the raw materials for preparation are commercially available products well known to those skilled in the art, unless otherwise specified.

[0056] After spin-coating a sacrificial layer and a flexible substrate photoresist on the surface of a silicon wafer, sequentially performing a first exposure, a first development and rinsing, a substrate layer is obtained.

[0057] Before the spin-coating, the silicon wafer is preferably pretreated, and the pretreatment preferably comprises sequentially performing cleaning, baking and cooling. In the present application, the cleaning is preferably conventional cleaning with deionized water. In the present application, the temperature of the baking is preferably 150°C, and the time is preferably 10 min. In the present application, the silicon wafer is preferably covered with a glass culture dish during the baking to avoid contamination by splashing of other liquids. In the present application, the purpose of the baking is to remove water vapor on the surface of the silicon wafer. The process of the cooling is not particularly limited in the present application, and can be performed using a process well known to those skilled in the art.

[0058] The present application does not have any special limitation to the process of spin-coating the sacrificial layer, and the process known to those skilled in the art can be used. In the present application, the process of spin-coating the flexible substrate photoresist is preferably spin-coating after dropping the flexible substrate photoresist on the surface of the silicon wafer. In the present application, the flexible substrate photoresist on the surface of the silicon wafer after dropping is preferably covering one-third of the surface area of the silicon wafer. In the present application, the flexible substrate photoresist is preferably polyimide photoresist (BL-301 photoresist). In the present application, the process of spin-coating the flexible substrate photoresist preferably includes first spin-coating, second spin-coating and third spin-coating in sequence, the first spin-coating is preferably at a speed of 10 rpm for 10 s; the second spin-coating is preferably at a speed of 1000 rpm for 30 s; and the third spin-coating is preferably at a speed of 1500 rpm for 40 s. In the present application, the thickness of the substrate layer obtained after spin-coating is preferably 15 μm.

[0059] After the spin-coating is completed, the present application also preferably includes placing the obtained silicon wafer coated with the flexible substrate photoresist on a smooth surface for standing; the standing time is preferably 5 min. In the present application, the standing time is preferably related to the thickness of the spin-coating, the thicker the thickness, the longer the standing time; the purpose of the standing is to make the flexible substrate photoresist uniformly distributed on the silicon wafer.

[0060] After the standing is completed, the present application also preferably includes soft baking, the temperature of the soft baking is preferably 100°C, and the time is preferably 4 min. In the present application, the soft baking is preferably performed on a hot plate.

[0061] In the present application, the first exposure preferably includes exposure preparation work and exposure in sequence.

[0062] In the present application, the exposure preparation work preferably includes: attaching a film to the surface of a transparent glass with the patterned side of the film facing down to obtain a glass substrate; and mounting the glass substrate as a mask plate on a photoetching machine.

[0063] In the present application, the film is attached to the surface of a transparent glass with the patterned side of the film facing down to obtain a glass substrate. In the present application, the attachment is preferably performed by using adhesive tape. In the present application, the patterned side of the film is facing down in order to contact the patterned side with the sample to be exposed. In the present application, the side of the glass substrate without the film attached is preferably smooth and complete, and cannot have protrusions to avoid the thickness of the glass substrate being able to be successfully mounted on the photoetching machine.

[0064] The glass substrate is installed as a mask plate on a photoetching machine. In the present application, the size of the mask plate is preferably larger than that of the silicon wafer. In the present application, the mask plate is preferably vacuum adsorbed on the mold surface of the photoetching machine by a gas pump.

[0065] In the present application, the first exposure preferably comprises: placing the silicon wafer with spin-coated flexible substrate photoresist on the stage of the photoetching machine, automatically loading the sample (the silicon wafer with spin-coated flexible substrate photoresist) into contact with the mask plate by the machine, and performing the first exposure. In the present application, the exposure dose of the first exposure is preferably 200 mJ / cm 2 , and the distance is preferably 10 μm.

[0066] After the first exposure, the present application further preferably comprises post-baking, the temperature of the post-baking is preferably 45℃, and the time is preferably 1 min. After the post-baking is completed, the present application further preferably comprises cooling, and the present application does not have any special limitation on the process of the cooling, and natural cooling by using the process well known to those skilled in the art can be adopted.

[0067] In the present application, the developing solution used in the first developing is preferably cyclopentane. In the embodiment of the present application, the developing solution used in the first developing is specifically RS120 developing solution. In the present application, the first developing is preferably performed by shaking in the developing solution; the present application does not have any special limitation on the process of the shaking, and the process well known to those skilled in the art can be adopted as long as the purpose of accelerating the developing speed can be achieved. In the present application, the rinsing solution used in the rinsing is preferably PGMEA rinsing solution. The present application does not have any special limitation on the process of the rinsing, and the process well known to those skilled in the art can be adopted.

[0068] After the rinsing is completed, the present application further preferably comprises placing the obtained sample to evaporate the liquid on the surface of the sample naturally.

[0069] After the rinsing is completed, the present application further preferably comprises hard baking. In the present application, the hard baking is preferably performed in a nitrogen atmosphere, the temperature of the hard baking is preferably 200-400℃, and more preferably 200℃; and the time is preferably 2 h.

[0070] After the substrate layer is obtained, the present application performs, in sequence, the second exposure and the second developing after the surface of the substrate layer is spin-coated with a negative photoresist, evaporates an electrode layer, removes the sacrificial layer on the surface of the silicon wafer, and attaches the obtained flexible functional layer to the surface of the self-expanding vascular stent, and the flexible substrate covers part of the surface of the grid structure of the expanded vascular stent, to obtain the super-flexible electronic device.

[0071] In the present application, the negative photoresist is preferably RN246 photoresist.

[0072] In the present application, the process of spin-coating the negative photoresist is preferably as follows: after the substrate layer is placed on the spin coater, the negative photoresist is added dropwise and then spin-coated.

[0073] In the present application, the surface of the substrate layer is not flat due to the presence of the polyimide layer, so when the negative photoresist is added dropwise, the negative photoresist will be distributed according to the pattern shape of the surface. If this distribution is not considered to be broken, it will lead to uneven distribution of the photoresist after spin-coating. Therefore, it is necessary to cover all the flexible substrate when spin-coating the negative photoresist.

[0074] In the present application, the spin-coating speed of the negative photoresist is preferably 4000 rpm, and the time is preferably 60 s.

[0075] In the present application, the thickness of the negative photoresist layer prepared by spin-coating is preferably 3.5 μm.

[0076] After the spin-coating is completed, the present application further preferably includes sequentially performing soft baking and cooling, the temperature of the soft baking is preferably 90°C, and the time is preferably 120 s. The present application does not have any special limitation on the process of cooling, which can be cooled to room temperature by using the process well known to those skilled in the art.

[0077] In the present application, the exposure dose of the second exposure is preferably 120 mJ / cm 2 , and the pitch is preferably 10 μm. In the present application, in order to ensure the accuracy of the position of the electrode pattern, the cross mark on the mask plate is preferably overlapped with the polyimide cross on the substrate layer during the second exposure.

[0078] After the second exposure is completed, the present application further preferably includes sequentially performing post-baking and cooling, the temperature of the post-baking is preferably 95°C, and the time is preferably 120 s. The present application does not have any special limitation on the process of cooling, which can be performed by using the process well known to those skilled in the art.

[0079] In the present application, the developing solution used in the second developing is preferably diluted NMD-3, the mass concentration of the NMD-3 is preferably 2.38%, and the mass concentration of the diluted NMD-3 is preferably 1.785%; the time of the second developing is preferably 30 s.

[0080] After the second developing is completed, the present application further preferably includes sequentially performing rinsing and drying, the rinsing solution used in the rinsing is preferably deionized water. In the present application, the rinsing solution used in the rinsing cannot use isopropyl alcohol, otherwise it will lead to the peeling of the RN246 photoresist layer. The present application does not have any special limitation on the process of drying, which can be performed by using the process well known to those skilled in the art to ensure that the surface is free of moisture, and then the electron beam evaporation plating can be performed.

[0081] In the present application, the rate of the evaporation is preferably 1 angstrom per second.

[0082] After the evaporation is completed, the present application also preferably comprises immersing the obtained product in acetone, and accelerating the falling of the metal layer (the part of the metal layer other than the electrode pattern) by heating or ultrasonic treatment.

[0083] The present application does not have any special limitation on the process of removing the silicon wafer and the attached process, and any process known to those skilled in the art can be used.

[0084] The present application also provides the application of the ultra-flexible electronic device in the field of smart support, which is prepared by the preparation method of the technical solution. The present application does not have any special limitation on the method of the application, and any method known to those skilled in the art can be used.

[0085] The ultra-flexible electronic device, the preparation method and the application thereof provided by the present application will be described in detail below in combination with examples, but they should not be understood as limitations on the protection scope of the present application.

[0086] Example 1

[0087] After the silicon wafer is cleaned with deionized water, the silicon wafer is covered with a glass culture dish, and then baked on a hot plate at 150℃ for 10min to remove the surface water vapor, and cooled to obtain a pretreated silicon wafer; then the spin coating of the sacrificial layer is carried out, and after the spin coating is completed, baking is carried out to obtain a silicon wafer covered with a sacrificial layer.

[0088] After the spin coating of the sacrificial layer on the surface of the pretreated silicon wafer is carried out, the BL-301 photoresist is added dropwise on the surface of the obtained silicon wafer covered with the sacrificial layer, and after the BL-301 photoresist covers about one third of the surface of the silicon wafer, spin coating is carried out (the spin coating includes spin coating at a speed of 10rpm for 10s, spin coating at a speed of 1000rpm for 30s, and then spin coating at a speed of 1500rpm for 40s), and then the silicon wafer after spin coating is placed on a smooth surface for 5min to make the photoresist uniformly distributed on the silicon wafer, and then baked on a hot plate at 100℃ for 4min to obtain a silicon wafer coated with photoresist;

[0089] The film is attached to the surface of the transparent glass with adhesive tape (and the side of the transparent glass without the attached film is smooth and complete), and then the glass substrate is installed as a mask plate on the photoetching machine (the size of the mask plate is larger than that of the silicon wafer coated with photoresist), and vacuum adsorbed on the surface of the mold using an air pump for exposure (the exposure dose of the exposure is 200mJ / cm 2After exposure (with a spacing of 10 μm), the sample was removed and baked on a hot plate at 45°C for 1 minute. After natural cooling, it was developed in RS120 developer (the development speed was accelerated by shaking during the development process) until the pattern was basically visible. Then, it was rinsed in PGMEA rinsing solution and allowed to stand until the liquid on its surface evaporated naturally. Finally, it was baked in a nitrogen atmosphere oven at 200°C for 2 hours to obtain a silicon wafer with a flexible substrate on its surface (the pattern of the flexible substrate layer is as follows). Figure 2 As shown in 'a', the actual object is shown in the image below. Figure 5 As shown in 'a', the thickness measurement results are as follows: Figure 5 (as shown in b in the text);

[0090] A layer of RN246 photoresist (covering the entire polyimide substrate layer, spin-coating at 4000 rpm for 60 s) is spin-coated onto the flexible substrate layer of the silicon wafer. After obtaining a photoresist layer with a thickness of 3.5 μm on the flexible substrate layer surface, it is soft-baked at 90°C for 120 s, cooled to room temperature, and then exposed (the exposure dose is 120 mJ / cm²). 2 (with a spacing of 10 μm), after exposure, the electrode was baked at 95°C for 120 s, cooled, and then developed in diluted NMD-3 (mass concentration of 1.785%) for 30 s. It was then rinsed in deionized water, dried at low temperature, and subsequently deposited sequentially at a rate of 1 Å / s using electron beam evaporation deposition of Cr with a thickness of 20 nm and Au with a thickness of 200 nm (the shape of the deposited electrode layer is as shown in the figure). Figure 3 As shown), after vapor deposition, the prepared sample is immersed in acetone and heated to 80°C or subjected to ultrasonic treatment to accelerate the shedding of the metal layer (the metal layer portion outside the desired electrode pattern). After removing the silicon wafer, the resulting flexible substrate functional layer (the actual physical images of the flexible substrate before and after stretching are shown in the figure) is obtained. Figure 6 As shown, a is a picture of the actual product before stretching, and b is a picture of the actual product after 120% stretching. Figure 6 It is known that the flexible substrate functional layer can be stretched to 120% of its original length, and its structure remains intact after multiple stretchings. Two electrodes are designed and fabricated on each patterned flexible substrate layer, as shown in the physical diagram. Figure 7 As shown, its resistance was measured to be 36.1 kΩ at both ends. The flexible substrate was attached to the surface of a self-expanding vascular stent (model HC*TDE-6020, purchased from Shanghai Xinwei Medical). (The diagram shows the connection between the flexible substrate and the self-expanding stent.) Figure 2 As shown in b), the flexible substrate covers part of the mesh wire surface of the expandable vascular stent, resulting in an ultra-flexible electronic device (as shown in the unfolded diagram). Figure 4 As shown in 'a', the stretched physical image is as follows: Figure 4 As shown in b, byFigure 4 It can be known that after the self-expanding vascular stent is expanded, the base layer shape can be matched with the stent, the self-expanding vascular stent and the flexible base layer are stretched together, and the two can be stretched together to simulate the condition of entering the stent into the catheter.

[0091] The above merely describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method for preparing a super flexible electronic device, characterized in that, the super flexible electronic device comprises a self-expandable vascular stent, a flexible substrate and an electrode which are sequentially stacked on the surface of the self-expandable vascular stent; the self-expandable vascular stent is a grid structure; the flexible substrate is in the shape of a grid and covers part of the surface of the grid structure; the electrode is on the surface of the flexible substrate; the grid structure of the self-expandable vascular stent is in the shape of a rhombus; the grid shape of the flexible substrate is the same as the shape of the grid structure of the self-expandable vascular stent, and several grid structures of the self-expandable vascular stent constitute one grid of the flexible substrate; the thickness of the flexible substrate is 10-200 μm, the line width of the rhombic bending part of the grid is 0.06 mm, and the line width of the rest of the grid is 1 mm; the method for preparing the super flexible electronic device comprises the following steps: after spin-coating a sacrificial layer and a flexible substrate photoresist on the surface of a silicon wafer, sequentially performing patterned first exposure, first development and rinsing to obtain a substrate layer; after spin-coating a negative photoresist on the surface of the substrate layer, sequentially performing patterned second exposure and second development, evaporating an electrode layer, removing the sacrificial layer on the surface of the silicon wafer, and attaching the obtained flexible functional layer to the surface of the self-expandable vascular stent, and the flexible substrate covers part of the surface of the grid structure of the self-expandable vascular stent, to obtain the super flexible electronic device.

2. The production method according to claim 1, wherein The material of the flexible substrate is polyimide.

3. The production method according to claim 1, wherein The electrode is further connected with a lead wire.

4. The production method according to claim 1 or 3, wherein The electrode comprises a first metal layer and a second metal layer which are sequentially stacked; the materials of the first metal layer and the second metal layer are different.

5. The production method according to claim 1, wherein The flexible substrate photoresist is a polyimide photoresist; the spin-coating of the flexible substrate photoresist comprises sequentially performing first spin-coating, second spin-coating and third spin-coating, the developing solution used in the first development is cyclopentanone, and the rinsing solution used in the rinsing is PGMEA rinsing solution; the first exposure further comprises soft baking before the first exposure; the first exposure further comprises post-baking after the first exposure; the rinsing further comprises hard baking after the rinsing.

6. The production method according to claim 1, wherein The negative photoresist is RN246 photoresist; the second exposure further comprises soft baking before the second exposure; the second exposure further comprises post-baking after the second exposure.

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