KR101738612B1 - Multifunctional Wearable Electronic Device and Method for Manufacturing the Same - Google Patents

Abstract

The present invention relates to a multifunctional wearable electronic device and a method of manufacturing the same. More particularly, the present invention relates to a biocompatible film that can be adhered to skin, a wearable electronic device including a stretchable and flexible electronic device attached to the biocompatible film, and a method of manufacturing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a multifunctional wearable electronic device and a manufacturing method thereof,

The present invention relates to a multifunctional wearable electronic device and a method of manufacturing the same. More particularly, the present invention relates to a biocompatible film that can be adhered to skin, a wearable electronic device including a stretchable and flexible electronic device attached to the biocompatible film, and a method of manufacturing the same.

Wearable electronic devices are electronic devices that can always be used in case of emergency because they can be worn on the human body. Recently, wearable electronic devices are expected to play an important role in the future human life. In order to realize a high performance electronic device which is thin and light and can be attached to the skin among these wearable devices, an extendable electronic device is manufactured using a very thin film and a serpentine electrode. In addition, these devices are placed on the neutral mechanical plane between the polymer layers to protect the fragile elements.

Devices equipped with wearable sensors that can continuously measure key physiological parameters and have data storage and drug delivery capabilities are expected to revolutionize personal healthcare. However, despite the fact that conventional monitoring devices capture notable physiological data only, they are not seamlessly integrated into the skin due to the form factor of existing devices, and are subject to wearability problems and signal-to- A problem arises.

To date, qualitative physiological parameters used to monitor diseases such as Parkinson's disease have been tracked through coarse monitoring cycles through video surveillance and delivery. However, in order to understand the progression of Parkinson's disease and other neurological diseases for drug therapy, there is a need for quantitative assessment and pattern analysis of physiological parameters from recorded data. In addition, compliance with oral administration on a daily basis presents the risk of side effects in the case of non-adherence and overdose. Thus, the efficacy of pharmacotherapy relies heavily on strategic monitoring, including controlled and sustained transdermal delivery, and ongoing monitoring of the patient's signs of a daily regimen.

Electronic systems, including inorganic and organic nanomaterials in flexible and stretchable structures, are powerful alternatives to bulky health monitoring devices, particularly due to their improved convenience, thereby improving compliance do. These currently emerging electronic devices include sensors, light emitting diodes, and associated circuitry that contacts internal organs (e.g., the heart, brain), the skin, or through an artificial skin scaffold. However, a major limitation to such soft and flexible electronic devices for wearable biomedical devices is that portable memory modules capable of real-time storage of recorded data in a continuous, long-term monitoring process have not yet been implemented. Another feature required for wearable devices presently being developed is the ability to perform advanced treatments in response to a diagnostic pattern present in the collected data.

A resistive random access memory (RRAM) fabricated from an oxide nanomembrane (NM) is a type of high performance non-volatile memory that is emerging today. RRAM devices constructed on conventional rigid substrates are made of a rigid and fragile material and thus tend to be mechanically incompatible with soft tissue that is curved and dynamically deformed. Although organic non-volatile memories enable flexible data-storage fabrication, limitations such as high power consumption, insufficient reliability and lack of physical synthesis still exist. Similarly, incorporating drug delivery devices comprised of a rigid microfluidic pump or a rigid electronic stimulator can pose serious problems to the mechanical integration of the human body with wearable electronic devices.

Conventional wearable devices are mostly in the form of making electronic devices on rigid substrates and simply wearing / wearing these devices. These devices can be actually worn / worn, but they are disadvantaged because they are bulky and heavy in weight, making them uncomfortable in daily life.

U.S. Patent Application Publication No. 20130041235 discloses a wearable device that is thin and lightweight electronic devices implanted into the skin. However, according to the above technology, since the electronic devices are placed on the sacrificial polymer layer, the wearable device is implanted into the skin through a method of removing the sacrificial polymer layer after putting it on the skin. However, in this case, since the wearable device is continuously exposed to foreign substances on the skin and may cause inflammation on the skin in the long term, there are many problems to be utilized for medical use.

The present invention implements this type of stretchable, thin and light wearable electronic devices on medical patches or bands to enable health diagnosis in daily life. Based on this, an integrated system And a manufacturing method thereof.

A basic object of the present invention is to provide a multifunctional wearable electronic device comprising a biocompatible film adherable to skin and a flexible and flexible electronic device attached to the biocompatible film.

Another object of the present invention is to provide a method for manufacturing a multi-functional wearable electronic device, which comprises attaching a flexible and soft electronic device to a biocompatible film that can be adhered to the skin.

It is still another object of the present invention to provide a method of manufacturing a semiconductor device, comprising: (i) sequentially coating a poly (methyl methacrylate) and a first polymer on a silicon substrate and curing; (ii) patterning the first polymer layer; (iii) fabricating an electronic device adjacent to the first patterned polymer layer; (iv) forming a second patterned polymer layer adjacent to the electronic device; (v) removing the silicon substrate and the poly (methyl methacrylate) to obtain a device encapsulated with the first polymer and the second polymer; (vi) removing the poly (methyl methacrylate) layer from the device encapsulated with the first polymer and the second polymer and attaching the poly (methyl methacrylate) layer to the elastic substrate; And (vii) attaching the device from which the poly (methylmethacrylate) layer has been removed from the elastic substrate to a biocompatible film attachable to the skin, wherein the first patterned polymer layer and the second patterned Wherein the first electrode and the second electrode of the electronic device adjacent to the polymer layer are each patterned.

The above-described basic object of the present invention can be achieved by providing a wearable electronic device including a biocompatible film adherable to skin and a flexible and flexible electronic device attached to the biocompatible film.

In the wearable electronic device of the present invention, the biocompatible film may be a polyurethane film coated with a hydrocolloid adhesive.

In addition, drug-filled mesoporous silica nanoparticles or biodegradable polymer nanoparticles may be contained on the surface of the biocompatible film (patch) coated with the hydrocolloid adhesive. The mesoporous silica nanoparticles or biodegradable polymer nanoparticles can be absorbed into the human body through the skin while releasing the drug packed in the nanoparticles.

The electronic device may be, but is not limited to, a memory device, a heater, a transistor, a temperature sensor, a strain sensor, an electromyogram sensor, an electroencephalogram sensor, or an integrated device including the same.

Figure 1 is a graphical representation of a comprehensive health examination / analysis / drug delivery system in the form of a patch, illustrating the use of electronic devices implemented on a patch in the case of a movement disorder. When a behavioral disorder occurs in a person wearing the patch-type electronic device, it is measured by a strain gauge on the patch, the measured data is stored in a memory (Wearable RRAM), and the stored data is analyzed Pattern analysis is used to drive the heater for feedback drug treatment (feedback thermal actuation), and drug delivery is achieved through drug-filled mesoporous silica nanoparticles or biodegradable polymer nanoparticles.

The memory device may be an active memory device such as a DRAM, flash memory, or spin-torque-transfer RAM, or may be a passive memory device such as resistive RAM, phase change RAM, or ferroelectric RAM.

The elastic and flexible electronic devices included in the wearable electronic device of the present invention include: an elastic substrate; A first patterned polymer layer formed adjacent to the elastic substrate; An electronic device formed adjacent to the patterned polymer layer; And a second patterned polymer layer formed adjacent to the memory element, wherein each of the first and second electrodes of the memory element adjacent to the first patterned polymer layer and the second patterned polymer layer comprises a pattern It may be anger.

As used herein, the term "stretchable and flexible electronic device" refers to an electronic device that exhibits a stable structure and operation even when deformed by stretching, compressing, bending, twisting,

The elastic substrate may be polydimethylsiloxane (PDMS), polyurethane, styrene-butadiene-styrene (SBS), epoxy resin or phenolic resin.

The first patterned polymer layer or the second patterned polymer layer may be selected from polyimide, benzocyclobutene or SU-8. As used herein, the term "SU-8" refers to an epoxy-based negative photoresist.

The first patterned polymer layer, the second patterned polymer layer, and the first patterned electrode and the second patterned electrode may be patterned in a serpentine pattern.

The electronic device included in the flexible and flexible electronic device of the present invention may be a memory device such as an active memory device or a passive memory device. The active memory device may be a DRAM, a flash memory, a spin-torque-transfer RAM (STT-RAM), or the like, and the passive memory device may include a Resistance RAM (RRAM), Phase Change RAM (PCRAM), Ferroelectric RAM (FERAM), and the like.

In particular, the electronic device included in the flexible and flexible electronic device of the present invention may be a non-volatile resistance memory device. The non-volatile resistive memory element comprising: a first patterned electrode; A non-conductive layer made of a first metal oxide formed adjacent to the first electrode; A metal nanoparticle layer formed adjacent to the first metal oxide nonconductor layer; A non-conductive layer made of a second metal oxide formed adjacent to the metal nanoparticle layer; And a second patterned electrode formed adjacent to the second metal oxide layer.

The first electrode may be selected from Al, Cu, Ag, Au, Pt, TiN, ITO, TaN, W, Mg, Zn or Fe.

The first metal oxide may be selected from titanium dioxide, tantalum oxide, vanadium oxide, molybdenum oxide, aluminum oxide, cobalt oxide, zinc oxide, magnesium oxide, zirconium oxide or hafnium oxide. The thickness of the first metal oxide nonconductor layer may be between 5 nm and 200 nm.

In addition, the metal nanoparticles may be Au, Pt, or Ag, and the size of the metal nanoparticles may be 2 nm to 100 nm. The metal oxide nanoparticle layer may be formed by a Langmuir-Blodgett, nano-layer, or spin-coating process of nanoparticles. Furthermore, the number of the metal oxide nanoparticle layers can be from 1 to 10, and can be adjusted to meet the required power. More preferably, the number of the metal oxide nanoparticle layers may be three.

As used herein, the term " Langmuir-blowjar assembly "refers to a solid substrate that is immersed in a liquid and then withdrawn to transfer one or more nanoparticle monolayers from the liquid subphase onto the solid substrate to form a two- Is formed.

As used herein, "self-assembly" refers to the process by which disordered systems of certain components form structured structures or patterns as a result of specific local interactions between the components.

The second metal oxide of the non-volatile resistive memory element may be selected from titanium dioxide, tantalum oxide, vanadium oxide, molybdenum oxide, aluminum oxide, cobalt oxide, zinc oxide, magnesium oxide, zirconium oxide or hafnium oxide. The thickness of the second metal oxide nonconductor layer may be between 5 nm and 200 nm.

The second patterned electrode may be selected from Al, Cu, Ag, Au, Pt, TiN, ITO, TaN, W, Mg, Zn or Fe.

In one embodiment of the present invention, Figures 2A and 2B illustrate a single crystal silicon nanomembrane (about 80 nm) strain sensor, a temperature sensor, a TiO ₂ nanomembrane (about 66 nm) RRAM array, and an electroresistive heater for the wearable electronic device. The multifunctional array of such sensors and memories is transferred over an elastic hydrocolloid patch (Derma-Touch, Kwang-Dong Pharmaceutical, Korea). In order to minimize the bending-induced strain, a switching TiO ₂ nanomembrane layer containing gold nanoparticles between the same polyimide layers (about 1.2 μm) was formed to form a neutral mechanical plane ( (Upper left of FIG. 2A). Further reducing flexural rigidity and induced strain by controlling the thickness of the inorganic active layer of a size of several tens of nanometers. The mesoporous silica nanoparticles charged with the therapeutic agent are transferred and printed on the hydrocolloid side of the skin patch (middle middle of FIG. 2A). Very thin winding wire and low modulus hydrocolloids together provide good mechanical contact with the skin. The inset of FIG. 2b is an enlargement of a 10 x 10 RRAM array in a serpentine network, which is integrated with a sensor that transmits analog output. Drugs filled in mesoporous silica nanoparticles diffuse into the dermis and the diffusion rate is controlled by the temperature of the hydrocolloid elastomer controlled by the heater. The temperature sensor warns of skin burns by providing temperature feedback on the spot.

Another object of the present invention can be achieved by providing a method for manufacturing a wearable electronic device, which comprises attaching a flexible and soft electronic device to a biocompatible film that can be adhered to the skin.

In the method for manufacturing a wearable electronic device, the biocompatible film may be a polyurethane film coated with a hydrocolloid adhesive.

In addition, drug-filled mesoporous silica nanoparticles or biodegradable polymer nanoparticles may be contained on the surface of the biocompatible film coated with the hydrocolloid adhesive. As the drug filled in the mesoporous silica nanoparticles is released, it can be absorbed by the human body through the skin.

The electronic device may be, but is not limited to, a memory device, a heater, a transistor, a temperature sensor, a strain sensor, an electromyogram sensor, an electroencephalogram sensor, or an integrated device including the same.

The memory device may be an active memory device such as a DRAM, flash memory, or spin-torque-transfer RAM, or may be a passive memory device such as resistive RAM, phase change RAM, or ferroelectric RAM.

It is still another object of the present invention to provide a method of manufacturing a semiconductor device, comprising: (i) sequentially coating a poly (methyl methacrylate) and a first polymer on a silicon substrate and curing; (ii) patterning the first polymer layer; (iii) fabricating an electronic device adjacent to the first patterned polymer layer; (iv) forming a second patterned polymer layer adjacent to the electronic device; (v) removing the silicon substrate and the poly (methyl methacrylate) to obtain a device encapsulated with the first polymer and the second polymer; (vi) removing the poly (methyl methacrylate) layer from the device encapsulated with the first polymer and the second polymer and attaching the poly (methyl methacrylate) layer to the elastic substrate; And (vii) attaching the device from which the poly (methylmethacrylate) layer has been removed from the elastic substrate to a biocompatible film attachable to the skin, wherein the first patterned polymer layer and the second patterned Wherein the first electrode and the second electrode of the electronic device adjacent to the polymer layer are patterned, respectively.

In the method of manufacturing the wearable electronic device, the elastic substrate may be polydimethylsiloxane, polyurethane, styrene-butadiene-styrene (SBS), epoxy resin or phenolic resin.

Also, the first polymer layer or the second polymer layer may be selected from polyimide, benzocyclobutene (BCB) or SU-8.

In addition, the electronic device may be selected from a memory device, a heater, a transistor, a temperature sensor, a strain sensor, an electromyogram sensor, an electroencephalogram sensor, or an integrated device including the same.

The first patterned polymer layer, the second patterned polymer layer, and the first patterned electrode and the second patterned electrode may be patterned in a serpentine pattern.

The electronic device may be a memory device such as an active memory device or a passive memory device. The active memory device may be a DRAM, a flash memory, a spin-torque-transfer RAM (STT-RAM), or the like, and the passive memory device may include a Resistance RAM (RRAM), Phase Change RAM (PCRAM), Ferroelectric RAM (FERAM), and the like.

In particular, the electronic device may be a non-volatile resistive memory device. Moreover, the non-volatile resistive memory element may comprise a first patterned electrode; A non-conductive layer made of a first metal oxide formed adjacent to the first electrode; A metal nanoparticle layer formed adjacent to the first metal oxide nonconductor layer; A non-conductive layer made of a second metal oxide formed adjacent to the metal nanoparticle layer; And a second patterned electrode formed adjacent to the second metal oxide layer.

In the method for manufacturing a wearable electronic device, the biocompatible film may be a polyurethane film coated with a hydrocolloid adhesive.

In addition, drug-filled mesoporous silica nanoparticles or biodegradable polymer nanoparticles may be contained on the surface of the biocompatible film coated with the hydrocolloid adhesive.

According to the present invention, by implementing an integrated medical electronic device on a very thin and light skin patch, a medical examination can be performed without inconvenience in daily life. In addition, since an integrated system capable of performing medication or additional medical care can be implemented using the present invention, it can be effectively applied to the treatment of diseases requiring continuous observation in daily life.

Fig. 1 shows one embodiment of the wearable electronic device of the present invention.
FIG. 2 is a schematic diagram of a wearable electronic device manufactured by Embodiment 2 of the present invention, in which a wearable memory array (also referred to as a wearable memory device) composed of a TiO ₂ nanomembrane (NM) -Au nanoparticles (NPs) -TiO ₂ NM switching layer and an Al electrode 2a, the upper left-hand inset shows the layer information), and a photograph of the wearable system corresponding to FIG. 2a is shown (FIG. 2b).
Figure 3a is a diagram illustrating Langmuir-BlowJet (LB) assembly and stearic acid (SAM) functionalization; FIG. 3B is a photograph of the LB assembly process (top) and plane TEM photographs (bottom) for 1-layer gold nanoparticles and 3-layer gold nanoparticles; Figure 3c is a cross-sectional TEM image of the fabricated memory cells; FIG. 3D is an EDS profile showing the thickness of a three-layer gold nanoparticle for a MINIM (metal-insulator-nanoparticle-nonconductor-metal).
4A is a schematic view of a third embodiment of the present invention in which MIM (metal-nonconductor-metal), MISIM (metal-insulated-self-assembled monolayer (SAM) IV characteristics of bipolar resistive switching of structures; Figure 4b is a diagram illustrating low current resistive switching due to gold NP-induced traps; 4c is an IV curve at MIM and MINIM attached to PDMS and encapsulated in polyimide; Figure 4d shows IV characteristics at a compliance current of about 100 A or less at MIM and MINIM attached to PDMS and encapsulated in polyimide; Figure 4e shows the results of the reliability test (durability (left) and retention (right)) of a MINIM encapsulated in polyimide attached to PDMS (resistance value measurement at -0.5 V); Figure 4f is the cumulative probability at MIM and MINIM attached to PDMS and encapsulated in polyimide; Figure 4g shows MIM (left-hand side) and MIM (right-hand side) MLC (multi-layer cell) operation attached to PDMS and encapsulated in polyimide.
FIG. 5 is a graph showing changes in the elongation and elongation of the flexible and flexible memory devices in Example 4 according to the present invention, in a microscope photograph (FIG. 5A) and a different strain value (3% - 25% (Fig. 5B) and flexed and soft resistive memory arrangements in a bent state (left in Fig. 5C) and in a twisted state (right in Fig. 5C) (The first frame from the left in Fig. 5D), the state without deformation (the second frame from the left in Fig. 5D), the compression state diagram (the third frame from the left in 5d), and the tension state (Fig. 5e), showing the resistance (HRS and LRS) changes at -0.5 V during 1,000 extension cycles (about 30%), showing the simulation results for strain distribution in elongated RRAM (Fig. 5F), water resistance in the PBS (Fig. 5G, left) It illustrates the flow (Fig. 5g right).
FIG. 6A is a schematic view showing a transfer printing process of drug filled mesoporous silica nanoparticles, a sensor and a memory device, and FIG. 6B is a photograph of a structured PDMS stamp used in the transfer printing process. FIG.
FIG. 7A is a photograph of a silicon nanomembrane sensor (the inset shows silicon nanocrystals doped with boron), FIG. 7B is the change in resistance versus strain plot for calculating the gauge factor, and FIG. Fig. 7D is a photograph of the strain measurement on the wrist in tension and compression, Fig. 7d shows the change in resistance (top) over time in the silicon strain gage caused by hand tremors simulated at frequencies of 0.8, 0.4, 0.6 and 1 Hz, The MLC operation of the cell (middle), and the data written to the MINIM memory cell (bottom).
8A is a schematic view of controlled transdermal drug delivery from hydrocolloid and mesoporous silica nanoparticles by thermal action, FIG. 8B shows a temperature distribution measurement of the heater on a skin patch using an infrared camera, FIG. 8C FIG. 8D shows a high-resolution camera photograph of the mesoporous silica nanoparticle (inset view is a microscopic photograph), FIG. 8E shows a photograph of the mesoporous silica nanoparticle 8f shows the surface area calculated from the adsorption and desorption measurements of N2 at 77 K (the degree of insertion is calculated from the mesoporous silica nanoparticles calculated using the Barrett-Joyner-Halenda (BJH) method (Orange) on the surface of the heater (red), the interface between the skin and the patch, and the system (Black), the y-axis on the right shows exponential increase of the diffusion coefficient with increasing temperature (blue in Fig. 8g), Fig. 8h shows the characteristic curve of the temperature sensor, FIG. 8I is a fluorescence image of a section of pig skin after diffusion of Rhodamine B fluorescent dye for 5 minutes (left) and 60 minutes (right) at 25 占 (top) and 40 占 (bottom)
Figure 9 is a packaging test result for erosion or performance degradation due to sweat when the RRAM memory module operates on the skin. The left photograph of FIG. 9 shows the evaluation of whether the memory operation becomes stable when a PBS (Phosphate Buffered Saline) solution is applied to the RRAM array on the PDMS substrate. The data on the right-hand side of Figure 9 shows whether the memory programmed at -0.5 V is good to store. It shows that the RRAM memory array packaging is good because no data is lost for 60 seconds.

Hereinafter, the present invention will be described in more detail with reference to the following examples or drawings. It is to be understood, however, that the following description of the embodiments or drawings is intended to illustrate specific embodiments of the invention and is not intended to be exhaustive or to limit the scope of the invention to the precise forms disclosed.

Example  1. Synthesis of gold nanoparticles

0.4 g of _{HAuCl 4 · 3H 2 O (99.9} %, Strem, USA), oleyl amine (90%, Acros, USA) and 30 mL of 1-octadecene (90%, Sigma Aldrich, USA ) at room temperature for 50 mL glass vial. The vial was placed in an oil bath and heated to 90 ° C. The solution was heated for 2 hours, after which the nanoparticles were precipitated, washed twice with ethanol and then centrifuged. The precipitated nanoparticles were redispersed in 5 mL of chloroform.

Example  2. A non-volatile memory device comprising a non- Wearable Electronic  making

(PMMA) (A11, Microchem, USA; about 1 μm, spin coated at 3000 rpm for 30 seconds) and polyamic acid (PI) (polyamic acid, Sigma Aldrich, coated for 60 seconds at rpm) was spin-coated onto a silicon handle wafer (test grade, 4science, Korea). After the PMMA and PI were cured at 200 ° C for 2 hours, aluminum used as a first electrode was deposited by thermal evaporation (350 nm thick), patterned by photolithography, and wet etched. Then, a first TiO ₂ nanomembrane (66 nm thick) was RF magnetron sputtered (base pressure: 5 × 10 ^-6 Torr, room temperature, deposition pressure: 5 mTorr, 20 sccm, RF Power 150 W) (first metal oxide nonconductor layer).

The gold nanoparticles synthesized in Example 1 were assembled on the first TiO ₂ nanomembrane through a LB assembly process (FIG. 3A) as follows. First, gold nanoparticles capped with oleylamine were dispersed in chloroform (50 mg / mL). The dispersion was added dropwise onto the water sub-phase of an LB trough (IUD 1000, KSV instrument, Finland). After evaporating the solvent, the surface layer was compressed using a mobile barrier (5 mm / min). After the surface pressure reached 30 mN / m, the substrate was lifted and immersed at a rate of 1 mm / min to assemble the gold nanoparticle layer on the substrate.

Figure 3b shows photographs (top) for the LB assembly process and plane TEM images (bottom) for one layer of gold nanoparticles and three layers of gold nanoparticles. The number of assembly layers can be controlled by the number of dipping / pulling cycles. Instead of the gold nanoparticle layer, the first TiO ₂ nanomembrane was coated with a self-assembled monolayer (stearic acid) to confirm the ligand effect on memory performance (FIG. 3A). (ii) a metal-non-conductor-nanoparticle (NP) comprising a layer of gold nanoparticles (about 12 nm), a nonconductor- MINIM, and iii) a MINIM containing three closely packed gold nanoparticles (about 26 nm) is shown in Figure 3c. The thickness of the three-layered gold nanoparticle layer was confirmed through an energy dispersive X-ray spectroscopy profile of the cross section (FIG. 3D). In the LB assembly, a closely-packed monolayer assembly plays an important role in device uniformity as well as precise thickness control of a plurality of single layers.

Then, using the same method as the deposition of the TiO ₂ nano-membrane of claim 1, it was deposited to a second TiO ₂ nano-membrane (second non-conductive metal oxide layer) on the gold nanoparticle layer (66 nm thick). An aluminum second electrode was deposited adjacent to the second TiO ₂ nanomembrane by thermal evaporation. The second electrode layer was patterned by a photolithography method to fabricate a serpentine-patterned resistance memory. Next, the PI precursor was spin-coated to form the active layer in the vicinity of the neutral mechanical plane, and a reactive ion etching (RIE) process using O ₂ and SF ₆ (O ₂ flow rate of 100 sccm, chamber pressure of 100 mTorr, 150 W RF power, 5 minutes, SF ₆ flow rate of 50 sccm, chamber pressure of 55 mTorr, 250 W RF power, 4 minutes and 30 seconds).

After the fabrication of the memory device, all devices on the silicon wafer were immersed in boiling acetone. The acetone removed the PMMA layer and separated the PI encapsulated device from the silicon handle wafer. Thereafter, the memory element was separated using a water-soluble tape (3M, USA), transferred onto printed PDMS (polydimethyl siloxane), and then applied again to a skin patch (Derma-Touch, Kwang Dong Pharmaceutical Co., Ltd., Korea) I moved up. Electrical measurements were performed using a parameter analyzer (B1500A, Agilent, USA).

Example  3. Characterization of Nonvolatile Resistive Memory Devices

To evaluate the electrical performance, a bipolar IV curve for MIM, MISIM and MINIM structures attached to PDMS and encapsulated in PDMS, prepared according to the method of Example 2, was determined (Fig. 4A ). The inset of FIG. 4A shows the bias order. The initial state is a high-resistance state (HRS), and a low-resistance state (LRS) transition occurs when a negative voltage ("set") is applied. Thereafter, the structures are switched to the HRS by a positive voltage ("reset"). The I-V characteristics of MIM and MISIM attached to PDMS and encapsulated in polyimide were nearly identical; The formation of one gold nanoparticle layer in the TiO2 layer reduced the set and reset currents by an order of magnitude compared to the MIM structure. The current level was further reduced by an order of three in the MIMIN containing three layers of gold nanoparticles. These results indicate that the assembly of uniform gold nanoparticles in the active layer plays an important role in reducing power consumption and that the stearic acid ligand has little effect on current reduction. This low power consumption characteristic plays an important role in the long-term use of the memory device.

Figure 4b is a diagram illustrating low current switching due to gold nanoparticle-induced traps. 4C is a log-log IV curve emphasizing the negative voltage region. The conduction mechanism in MINIM, which is attached to PDMS and encapsulated in polyimide, is similar to the conduction mechanism of MIM, and the trap-controlled space-charge-limited-current (SCLC) theory . Figure 4d shows IV curves at different compliance currents for MIM (left) and MINIM (right) attached to PDMS and encapsulated in polyimide. At a compliance current of less than 100 μA, MINIMs attached to PDMS and encapsulated with polyimide showed better on / off ratio than MIM and MISIM attached to PDMS and encapsulated with polyimide. The reliability (endurance and retention) of MINIM, MIM and MISIM attached to PDMS and encapsulated in polyimide are shown in Figure 4E, respectively. Durability was not substantially degraded in continuous sweeping over 100 cycles (left side in FIG. 4e), and good retention rate from room temperature to 1,000 seconds was confirmed (right side in FIG. 4e). Multi-level cell (MLC) operation means that multiple data storage is possible in a single cell with a discrete compliance current that has a discrete resistance value (FIG. 4D). These different resistance values allow multiple information to be stored in a single cell (FIG. 4G). An MLC with a current value of -100 μA or less was performed in a MINIM encapsulated in a polyimide attached to a PDMS, and the data was preserved in read operations over 100 times.

Example  4. Mechanical Stability of Flexible and Flexible Resistive Memory Devices

Optical microscope photographs of the flexible and flexible resistive memory devices prepared in Example 2 and characteristics in the stretching process are shown in FIGS. 5A and 5B, respectively. When the device was elongated about 25% (deformation limit of human epidermis was about 20%), the device showed stable electrical operation. The flexible and flexible resistive memory device was also stable in bending and twisting (Figure 5c). In addition, in the second embodiment, the wearable electronic apparatus fabricated from the flexible and flexible resistance memory element was deformed in accordance with human skin (Fig. 5D). Figure 5E shows finite element modeling (FEM) results for the strain distribution of the active layer (TiO ₂ nanomembrane). By placing nanometer-scale membranes and nanoparticles on a neutral mechanics layer and adopting a serpentine design, the induced strain is kept below 0.1% in the switching layer, And less than 0.05% for serpentine interconnects. The skin-adaptive memory showed minimal signal reduction after 1,000 stretch cycles (about 30% strain, Fig. 5f). Figure 5g shows a photograph (left side) of the memory device in phosphate buffered saline and a point without significant current change (right side), which means that the encapsulation layer can block perspiration uptake.

Example  5. Siege ( mesoporous ) Synthesis of Silica Nanoparticles

NaOH (0.35 mL, 2M, 98%, Sigma-Aldrich, USA) was added to 50 mL of cetyltrimethylammonium bromide (CTAB,> 99%, Acros, USA) solution (100 mg dissolved in 50 mL of water) . The mixture was heated to 70 < 0 > C and then 0.5 mL of tetraethylorthosilicate (TEOS, 98%, Acros, USA) was added. After 1 minute, 0.5 mL of ethyl acetate (99.5%, Samchun, Korea) was added and the mixture thus obtained was stirred at 70 DEG C for 30 seconds and then aged for 2 hours. The precipitate thus obtained was collected by centrifugation and washed with a large amount of water and ethanol. Finally, mesoporous silica (m-silica) nanoparticles were prepared by removing the pore-generating template, CTAB, by reflux in an acidic ethanol solution.

Example  6. Siege  To silica nanoparticles Rhodamine  B ( Rhodamine  B) Charge the fluorescent dye

Rhodamin B (≥95%, Sigma-Aldrich, USA) was loaded into mesoporous silica nanoparticles as a drug diffusion model. Rhodamine B solution (0.2 mL, 20 mg / mL in methanol) was adsorbed onto the surface of the mesoporous silica nanoparticles (0.15 g). Rhodamine B filled in the mesoporous silica nanoparticles was dried at room temperature.

Example  7. Drug-filled Siege  Structured PDMS stamps for transfer printing to silica nanoparticles ( structured PDMS stamp ) Production

A negative photoresist (SU8-25, Microchem, USA) was pre-cleaned and spin-coated onto a silicon wafer treated with O ₂ plasma. The spin-coated SU8 was photolithographically patterned to form holes 40 μm deep, 600 μm wide and 1.46 nm apart. Next, the SU8 mold was placed on a heated dish on a plate at 150 DEG C to facilitate adhesion between the mold and the silicon wafer. 10: 1 PDMS (Sylgard 184A: Sylgard 184B, Dow Corning, USA) was poured into the dish. After 24 hours, the cured structured PDMS and micro-dot array were slowly removed from the SU8 mold (Fig. 6B).

Example  8. Drug-filled Siege  Transfer printing on skin patches of silica nanoparticles

The drug filled (or dye-filled) mesoporous silica nanoparticle solution was dropped onto the structured PDMS stamp. The stamp was dried for about 20 minutes. The dried dye-filled mesoporous silica nanoparticles were transferred and printed onto the hydrocolloid side of the skin patch as a microdot array (Fig. 6A).

Example  9. Measurement of temperature distribution of heater using infrared camera

A wavy-patterned Cr / Au-based heater (10 nm / 190 nm, line width 300 μm, 95.9 Ω) on a 1 mm thick slide glass was placed at a power source (12 V, 1.5 W). A time-dependent thermo-gram was captured using an infrared camera (320 x 240 pixels, IRE Korea, Korea) and the maximum temperature of the heater was shown.

Example  10. Single crystal silica on skin patch Nanomembrane  Strain ( strain ) Fabrication of sensor

The manufacturing process was started by spin coating PMMA and PI on a silicon wafer. Doped with boron (dopant concentration: about ^{9.7 × 10 18 / cm 3)} SOI (silicon-on-insulator) photolithography and RIE of the wafer 80 nm by (SF ₆ plasma, 50 sccm, the chamber pressure was 50 mTorr) process Thick silicon nanomembrane was formed, which was then transferred and printed on the PI film. Thermal evaporation was then used for subsequent metallization (Cr / Au, 7 nm / 70 nm thick) and then a metal film was formed as a specific pattern by photolithography and wet chemical etching. Next, the top PI layer was covered and all three layers (PI / device / PI) were patterned and etched by O ₂ and SF ₆ RIE. The entire device was removed from the silicon wafer by removing the PMMA sacrificial layer using acetone. The removed device was transferred and printed on a skin patch.

Figure 7a shows an arrangement of elastic strain sensors based on silicon nanomembranes (insertions) as a typical example of a wearable sensor adjacent to a memory juxtaposed. The strain gauge has an effective guage factor of about 0.5. Due to the very thin serpentine interconnect, the sensors were well adapted to the skin during repeated exposure to tension and compression on the human wrist (Figure 7c). This specific example mimics a tremor mode that causes hand shaking at different frequencies, as seen in epilepsy and Parkinson's disease (Fig. 7d). The other shaking frequency serves as the main tracking factor to monitor and diagnose this movement disorder. Representative frequencies corresponding to the different frequency bands (0.-0.5, 0.5-0.7, 0.7-0.9 and > 0.9 Hz) are generated at four different levels based on the MLC operation of the MINIM wearable memory Lower part).

Example  11. Manufacture of electric resistance heater / temperature sensor on skin patch

A skin-mountable heater was fabricated by thermal evaporation of Cr / Au (10 nm / 190 nm thick) through a meandering metal mask (metal masks) to form a non-adherent surface (hydrocolloid hydrocolloid). After the wiring operation, the heater was wrapped with a PDMS film. The same design and fabrication method can be used for the temperature sensor.

Example  12. Data processing and storage system

By capturing the physiological strain signal using the mounted sensor, the sensing and data storage steps can be initiated and stored locally in the cell of the non-volatile memory. For this system, the recorded data was processed and stored using a custom program written in Lab View software (National Instruments, USA). For example, in the case of strain sensing for a tremor model in motion-related neurological disorders (Fig. 7d), the tremor recorded by the loaded strain gauge Were analyzed and classified into four different bands (0-0.5, 0.5-0.7, 0.7-0.9, and> 0.9 Hz) by the customized Lab View program. Under MLC operation via a probe station, the program determines the appropriate compliance current and bias voltage to generate two specific digit codes ([00], [01], [10], and [ , Which are preliminarily assigned to the respective bands) are recorded in the wearable memory cell mounted.

Applications for sensing and data storage use stored information to trigger initiation of therapy. One possible use is to supply the recorded data through a control circuit that recognizes a characteristic pattern of the disease, followed by triggering / controlling drug release (Fig. 8A). We used mesoporous silica nanoparticles as vehicles (Figures 8d-8f) containing and delivering drugs and used diffusion promoting / temperature monitoring devices (Figures 8b, 8c, 8g and 8h) for controlled transdermal drug delivery An electroresistive heater / temperature sensor was used (Fig. 8I). Using a structured polydimethylsiloxane (PDMS) stamp, drug filled mesoporous silica nanoparticles were trasfer-printed onto the tacky side of the patch. The mesoporous silica nanoparticles containing nanopores (FIG. 8E) have a very large surface area for drug adsorption (FIG. 8F). Figure 8b shows a thermal gradient photo (infrared camera measurement) for an electrically resistive heater on the patch surface. Figure 8c shows the corresponding FEM analysis results highlighting the three dimensional thermal profile of the device on a multi-layered human skin, demonstrating that sufficient heat is transferred to the skin and the nanoparticles. The heat generated in the heater breaks the physical connection between the nanoparticles and the drug, so that the drug filled in the nanoparticles is transdermally diffused. As a result of the FEM simulation, it was confirmed that the diffusion rate was increased by heating (Fig. 8G). The maximum temperature (< 43 [deg.] C) that can prevent the skin image can be monitored by the temperature sensor (Fig. 8H). Transdermal drug delivery can be visualized by fluorescence microscopy that the dye (rhodamine B) diffuses into the skin of the pig at room temperature (25 占 폚, top of Fig. 8i) and at elevated temperature (40 占 폚, bottom of Fig. 8i) . The depth at which the dye penetrated the pig skin at room temperature was shallower than the penetration depth at elevated temperature, indicating that diffusion was accelerated by thermal action.

Example  13. Analysis of Packaging Performance of Electronic Devices Installed on Patch

Electronic components must be prevented from malfunctioning by sweat from the human skin, or foreign matter such as external water, through packaging. The electronic devices fabricated by the method of Example 3 were well protected by an encapsulation layer, and their performance was almost unchanged by the stimulation of external substances such as sweat. As shown in FIG. 9, when a 1 M solution of PBS (Phosphate Buffered Saline Solution) having a much higher ion concentration than sweat was dropped on the electronic device, it was observed that the electronic device worked well without any abnormality.

Claims (41)

A biocompatible film adherable to the skin; and a flexible and flexible electronic device attached to the biocompatible film,
The biocompatible film is a film coated on one side with a hydrocolloid adhesive,
Characterized in that the biocompatible film contains drug-loaded mesoporous silica nanoparticles or biodegradable polymer nanoparticles on the surface to which the hydrocolloid adherend is applied,
The stretchable and flexible electronic device includes:
An elastic substrate;
A first patterned polymer layer formed adjacent to the elastic substrate;
An electronic device formed adjacent to the first patterned polymer layer;
And a second patterned polymer layer formed adjacent to the electronic device,
Wherein each of the first electrode and the second electrode of the electronic device adjacent to the first patterned polymer layer and the second patterned polymer layer is patterned. The wearable electronic device according to claim 1, wherein the biocompatible film is a polyurethane film coated with a hydrocolloid adhesive. delete The wearable electronic device according to claim 1, wherein the electronic device is at least one selected from the group consisting of a memory device, a heater, a transistor, a temperature sensor, a strain sensor, an EMG sensor, an EEG sensor, . 5. The wearable electronic device of claim 4, wherein the memory element is a non-volatile resistive memory element. delete The wearable electronic device according to claim 1, wherein the elastic substrate is selected from the group consisting of polydimethylsiloxane, polyurethane, styrene-butadiene-styrene rubber, epoxy resin and phenol resin. The wearable electronic device according to claim 1, wherein the first patterned polymer layer or the second patterned polymer layer is selected from the group consisting of polyimide, benzocyclobutene, and SU-8. The method of claim 1, wherein the first patterned polymer layer, the second patterned polymer layer, and the first patterned electrode and the second patterned electrode are patterned in a serpentine pattern Wherein the wearable electronic device is a wearable electronic device. The wearable electronic device according to claim 1, wherein the electronic device is an active memory device or a passive memory device. 11. The wearable electronic device of claim 10, wherein the active memory device is selected from the group consisting of a DRAM, a flash memory, and a spin-torque transfer RAM. 11. The wearable electronic device of claim 10, wherein the passive memory device is selected from the group consisting of a resistance RAM, a phase change RAM, and a ferroelectric RAM. The wearable electronic device according to claim 1, wherein the electronic device is a non-volatile resistance memory device. 14. The non-volatile memory device of claim 13,
A first electrode;
A non-conductive layer made of a first metal oxide formed adjacent to the first electrode;
A metal nanoparticle layer formed adjacent to the first metal oxide nonconductor layer;
A non-conductive layer made of a second metal oxide formed adjacent to the metal nanoparticle layer; And
And a second electrode formed adjacent to said second metal oxide layer. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &
Wearable electronic device. The wearable electronic device according to claim 14, wherein the first electrode is selected from the group consisting of Al, Cu, Ag, Au, Pt, TiN, ITO, TaN, W, Mg, Zn and Fe. 15. The method of claim 14, wherein the first metal oxide is selected from the group consisting of titanium dioxide, tantalum oxide, vanadium oxide, molybdenum oxide, aluminum oxide, cobalt oxide, zinc oxide, magnesium oxide, zirconium oxide, Wearable electronic device characterized by. 15. The wearable electronic device according to claim 14, wherein the first metal oxide nonconductor layer has a thickness of 5 nm to 200 nm. 15. The wearable electronic device according to claim 14, wherein the metal nanoparticles are nanoparticles of a metal selected from the group consisting of Au, Pt and Ag. 15. The wearable electronic device according to claim 14, wherein the size of the metal nanoparticles is 2 nm to 100 nm. 15. The wearable electronic device of claim 14, wherein the metal nanoparticle layer is formed by a process selected from the group consisting of Langmuir-Blodgett assembly, layer-by-layer assembly and spin- . 15. The wearable electronic device according to claim 14, wherein the number of the metal nanoparticle layers is one to ten layers. 15. The method of claim 14 wherein said second metal oxide is selected from the group consisting of titanium dioxide, tantalum oxide, vanadium oxide, molybdenum oxide, aluminum oxide, cobalt oxide, zinc oxide, magnesium oxide, zirconium oxide and hafnium oxide Wearable electronic device characterized by. The wearable electronic device according to claim 14, wherein the thickness of the second metal oxide nonconductor layer is 5 nm to 200 nm. The wearable electronic device according to claim 14, wherein the second electrode is selected from the group consisting of Al, Cu, Ag, Au, Pt, TiN, ITO, TaN, W, Mg, Zn and Fe. Attaching a flexible and soft electronic component to a biocompatible film that is adherable to the skin,
The biocompatible film is a film coated on one side with a hydrocolloid adhesive,
Characterized in that the biocompatible film contains drug-loaded mesoporous silica nanoparticles or biodegradable polymer nanoparticles on the surface to which the hydrocolloid adherend is applied,
The stretchable and flexible electronic device includes:
An elastic substrate;
A first patterned polymer layer formed adjacent to the elastic substrate;
An electronic device formed adjacent to the first patterned polymer layer;
And a second patterned polymer layer formed adjacent to the electronic device,
Wherein each of the first electrode and the second electrode of the electronic device adjacent to the first patterned polymer layer and the second patterned polymer layer is patterned. 26. The method of claim 25, wherein the biocompatible film is a polyurethane film coated with a hydrocolloid adhesive. delete 26. The wearable electronic device according to claim 25, wherein the electronic device is at least one selected from the group consisting of a memory device, a heater, a transistor, a temperature sensor, a strain sensor, an electromyogram sensor, Gt; 26. The method of claim 25, wherein the electronic device is a non-volatile resistive memory device. delete (i) sequentially coating and curing poly (methyl methacrylate) and a first polymer on a silicon substrate;
(ii) patterning the first polymer layer;
(iii) fabricating an electronic device adjacent to the first patterned polymer layer;
(iv) forming a second patterned polymer layer adjacent to the electronic device;
(v) removing the silicon substrate and the poly (methyl methacrylate) to obtain a device encapsulated with the first polymer and the second polymer;
(vi) removing the poly (methyl methacrylate) layer from the device encapsulated with the first polymer and the second polymer and attaching the poly (methyl methacrylate) layer to the elastic substrate; And
(vii) attaching the device from which the poly (methylmethacrylate) layer has been removed from the elastic substrate to a biocompatible film attachable to the skin,
Wherein each of the first electrode and the second electrode of the electronic device adjacent to the first patterned polymer layer and the second patterned polymer layer is patterned,
The biocompatible film is a film coated on one side with a hydrocolloid adhesive,
Wherein the biocompatible film contains drug-loaded mesoporous silica nanoparticles or biodegradable polymer nanoparticles on the surface to which the hydrocolloid adherend is applied. 32. The method of claim 31, wherein the elastic substrate is selected from the group consisting of polydimethylsiloxane, polyurethane, styrene-butadiene-styrene rubber, epoxy resin, and phenol resin. 32. The method of claim 31, wherein the first polymer layer or the second polymer layer is selected from the group consisting of polyimide, benzocyclobutene, and SU-8. 32. The method of claim 31, wherein the first patterned polymer layer, the second patterned polymer layer, and the first patterned electrode and the second patterned electrode are patterned in serpentine Wherein the method comprises the steps of: 32. The method of claim 31, wherein the electronic device is at least one selected from the group consisting of a memory device, a heater, a transistor, a temperature sensor, and a strain sensor. 36. The method of claim 35, wherein the memory device is an active memory device selected from the group consisting of a DRAM, a flash memory, and a spin-torque transfer RAM. 36. The method of claim 35, wherein the memory device is a passive memory device selected from the group consisting of resistive RAM, phase change RAM, and ferroelectric RAM. 32. The method of claim 31, wherein the electronic device is a non-volatile resistive memory device. 39. The non-volatile memory device of claim 38,
A first patterned electrode;
A non-conductive layer made of a first metal oxide formed adjacent to the first electrode;
A metal nanoparticle layer formed adjacent to the first metal oxide nonconductor layer;
A non-conductive layer made of a second metal oxide formed adjacent to the metal nanoparticle layer; And
And a second patterned electrode formed adjacent to the second metal oxide layer. 32. The method of claim 31, wherein the biocompatible film is a polyurethane film coated with a hydrocolloid adhesive. delete

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