Ultraviolet radiation dose monitor and preparation method thereof

Abstract

In the ultraviolet radiation dose monitor described in the present invention, the lower electrode works as an auxiliary electrode in coordination with the device to control the electric field in the organic semiconductor layer and the insulating layer; the insulating layer blocks the connection between the lower electrode and the organic photochromic material-polymer composite film layer, thereby preventing the carriers in the channel between the upper electrode groups from flowing to the lower electrode; the upper electrode group controls the electric field of the organic photochromic material-polymer composite film layer and the organic semiconductor layer; the organic photochromic material-polymer composite film layer serves as a dielectric layer, and when the device is working, when it is irradiated with ultraviolet light, the properties such as the structure of the organic photochromic material change, and charge is stored, so that the transmission current between the upper electrode groups changes, while under light with a wavelength greater than that of ultraviolet rays or in dark conditions, the current does not change, and the change in the channel current between the upper electrodes corresponds one-to-one to the ultraviolet radiation dose, and can directly reflect the cumulative amount of ultraviolet radiation.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to an ultraviolet radiation dose monitor and a preparation method thereof. Background Art

[0002] The advent of the information age has given rise to the development of Internet of Things technology. The development of new electronic devices for Internet of Things technology has become an important part of today's electronic information technology, and it is also one of the most important basic academic research hotspots and frontiers. Novel wearable electronic devices have shown great application potential and value in the fields of health protection and environmental monitoring. Especially with the increasing awareness of health and environmental protection, wearable electronic devices that monitor human physiological signals and environmental signals such as ultraviolet radiation and air quality are becoming more and more popular. Wearable electronic ultraviolet radiation dose monitors can record ultraviolet radiation doses in a personalized manner, providing users with more accurate reference information to prevent damage from excessive ultraviolet rays, which is of great significance to protecting life and health.

[0003] Existing wearable UV monitoring devices are mainly divided into two types: photoelectric sensors and monitoring devices based on photochromic materials. Photoelectric sensors convert UV radiation into electrical signals. They are mostly made of inorganic semiconductors and use semiconductors with a band gap width close to the measured photon energy to screen and identify UV light. The molecules in monitoring devices based on photochromic materials will change due to the accumulation of UV radiation, resulting in changes in the light absorption curve, and the presence or absence of light can be judged by color changes.

[0004] Photoelectric sensors can only detect instantaneous UV radiation intensity, but cannot directly record the cumulative amount of UV radiation, making it difficult to reflect the continuous impact of UV radiation on the human body. If the radiation dose is calculated by integrating frequent sampling, it has the disadvantages of high power consumption, low precision, and complex processing equipment. Monitoring equipment based on photochromic materials often requires the use of a spectrophotometer to detect because the color change area is not within the visible light range or the degree of change is too small, which greatly reduces the portability of the equipment. Even visible color changes are limited by the human eye's ability to distinguish, with limited precision and difficult to unify standards. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problems of low precision and high power consumption in the prior art.

[0006] In order to solve the above technical problems, the present invention provides an ultraviolet radiation dose monitor, comprising:

[0007] A flexible substrate layer;

[0008] A lower electrode, firmly connected to the upper surface of the flexible substrate layer, for controlling the electric field in the organic semiconductor layer and the insulating layer;

[0009] The insulating layer is firmly connected to the upper surface of the lower electrode, the area of ​​the insulating layer is smaller than the area of ​​the lower electrode, and the insulating layer is used to block the connection between the lower electrode and the organic photochromic material-polymer composite film layer;

[0010] The organic photochromic material-polymer composite film layer is firmly connected to the upper surface of the insulating layer. The organic photochromic material-polymer composite film layer acts as a dielectric layer and stores electric charge when exposed to ultraviolet light, so that the transmission current between the upper electrode groups changes. However, the current does not change under light with a wavelength greater than ultraviolet light or in dark conditions.

[0011] An organic semiconductor layer, which is firmly connected to the upper surface of the organic photochromic material-polymer composite film layer, and is used to control the flow of carriers and generate an adjustable and variable current;

[0012] The upper electrode group includes a first upper electrode and a second upper electrode, wherein the first upper electrode is firmly connected to the upper surface of the organic semiconductor layer, and the lower surface of the second electrode is firmly connected to the lower electrode and the upper surface of the organic semiconductor layer, respectively. The upper electrode group is used to control the electric field of the organic photochromic material-polymer composite film layer and the organic semiconductor layer.

[0013] In one embodiment of the present invention, the composite material of the organic photochromic material and the polymer is a spiropyran-poly (2-vinylnaphthalene) composite film material.

[0014] In one embodiment of the present invention, the flexible substrate layer is one of PET, PI, PEN or a heavily doped silicon wafer with a silicon oxide layer.

[0015] In one embodiment of the present invention, the lower electrode is one of gold, aluminum, copper metal films, an ITO transparent electrode or an organic material graphene.

[0016] In one embodiment of the present invention, the insulating layer is a parylene, aluminum oxide or silicon oxide film.

[0017] In one embodiment of the present invention, the insulating layer is a thin film of an organic material or an inorganic material.

[0018] In one embodiment of the present invention, the organic semiconductor layer is pentacene, a carbon small molecule semiconductor material or a polymer semiconductor.

[0019] In one embodiment of the present invention, the upper electrode group is gold or copper.

[0020] The present invention also provides a method for preparing an ultraviolet radiation dose monitor, which is characterized by comprising:

[0021] cleaning the substrate;

[0022] preparing a lower electrode on the substrate;

[0023] preparing an insulating layer on the lower electrode;

[0024] preparing an organic photochromic material-polymer composite film layer on the insulating layer;

[0025] preparing an organic semiconductor thin film on the organic photochromic material-polymer composite film layer;

[0026] A group of upper electrodes is prepared on the organic semiconductor film, wherein the group of upper electrodes comprises a first electrode and a second electrode, and the lower surface of the second electrode is tightly connected to the lower electrode and the upper surface of the organic semiconductor layer respectively.

[0027] In one embodiment of the present invention, the cleaning substrate comprises:

[0028] The flexible substrate was ultrasonically cleaned in acetone, isopropanol, anhydrous ethanol and deionized water for fifteen minutes each, and then dried with high-purity nitrogen.

[0029] The above technical solution of the present invention has the following advantages compared with the prior art:

[0030] In the ultraviolet radiation dose monitor of the present invention, the lower electrode works as an auxiliary electrode to cooperate with the device, is used to control the electric field in the organic semiconductor layer and the insulating layer, and is short-circuited with one electrode in the upper electrode group, and the external circuit is simplified under the condition of ensuring the accuracy of the measurement result; the insulating layer blocks the connection between the lower electrode and the organic photochromic material-polymer composite film layer, and prevents the carriers in the channel between the upper electrode groups from flowing to the lower electrode; the upper electrode group controls the electric field of the organic photochromic material-polymer composite film layer and the organic semiconductor layer; the organic photochromic material-polymer composite film layer serves as a dielectric layer, when the device is working, when it encounters ultraviolet light irradiation, the properties such as the structure of the organic photochromic material change, and charge is stored, so that the transmission current between the upper electrode groups changes, while under light with a wavelength greater than ultraviolet light or in dark conditions, the current does not change, and the change of the channel current between the upper electrodes corresponds to the ultraviolet radiation dose one by one, which can directly reflect the cumulative amount of ultraviolet radiation; the ultraviolet radiation dose monitor of the present invention is small in size, simple in structure, and low in power consumption, and a single device can directly monitor the ultraviolet radiation dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein

[0032] Figure 1 It is a structural schematic diagram of the ultraviolet radiation dose monitor of the present invention;

[0033] Figure 2 The response curve of the current of the ultraviolet radiation dose monitor of the present invention as the ultraviolet radiation dose changes;

[0034] Figure 3 The present invention is a flow chart of a method for preparing an ultraviolet radiation dose monitor. DETAILED DESCRIPTION

[0035] The core of the invention is to provide an ultraviolet radiation dose monitor and a preparation method thereof, which has low power consumption and high precision.

[0036] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0037] Reference Figure 1 As shown, the ultraviolet radiation dose monitor provided by the present invention comprises:

[0038] Flexible substrate layer 10, the material of which can be selected from flexible substrates such as PET, PI or PEN, and the material of the flexible substrate 10 can also be selected from heavily doped silicon wafers with silicon oxide layers, wherein the heavily doped silicon wafers have good electrical conductivity and can act as a gate, and the silicon oxide layer can act as an insulating layer;

[0039] The lower electrode 20 is firmly connected to the upper surface of the flexible substrate layer and is used to control the electric field in the organic semiconductor layer and the insulating layer. The lower electrode can be made of gold, aluminum or copper metal film, or an ITO transparent electrode, or graphene;

[0040] The insulating layer 30 is firmly connected to the upper surface of the lower electrode. The area of ​​the insulating layer is smaller than that of the lower electrode. The insulating layer is used to block the connection between the lower electrode and the organic photochromic material-polymer composite film layer. The insulating layer can be made of parylene, aluminum oxide or silicon oxide film, or other organic or inorganic material films;

[0041] The organic photochromic material-polymer composite film layer 40 is firmly connected to the upper surface of the insulating layer. The organic photochromic material-polymer composite film layer acts as a dielectric layer. When exposed to ultraviolet light, it stores charges, so that the transmission current between the upper electrode groups changes. However, under light with a wavelength greater than ultraviolet light or in dark conditions, the current does not change. The organic photochromic material-polymer composite film layer includes but is not limited to spiropyran (SP)-poly (2-vinyl naphthalene) (PVN) composite film material;

[0042] The organic semiconductor layer 50 is firmly connected to the upper surface of the organic photochromic material-polymer composite film layer, and is used to control the flow of carriers and generate an adjustable and variable current. The organic semiconductor layer can be made of pentacene or carbon 60 small molecule semiconductor materials, or can be made of polymer semiconductors;

[0043] The upper electrode group 60 includes a first upper electrode 602 and a second upper electrode 601. The first upper electrode is firmly connected to the upper surface of the organic semiconductor layer, and the lower surface of the second electrode is firmly connected to the lower electrode and the upper surface of the organic semiconductor layer, respectively. The upper electrode group is used to control the electric field of the organic photochromic material-polymer composite film layer and the organic semiconductor layer. The upper electrode group can be made of metal materials such as gold, silver, copper, or graphene.

[0044] The ultraviolet radiation dose monitor described in the present invention is a flexible wearable ultraviolet radiation dose monitor.

[0045] In the ultraviolet radiation dose monitor described in the present invention, the lower electrode works as an auxiliary electrode to cooperate with the device, is used to control the electric field in the organic semiconductor layer and the insulating layer, and is short-circuited with one electrode in the upper electrode group, thereby simplifying the external circuit while ensuring the accuracy of the measurement result; the insulating layer blocks the connection between the lower electrode and the organic photochromic material-polymer composite film layer, thereby preventing the carriers in the channel between the upper electrode groups from flowing to the lower electrode; the upper electrode group controls the electric field of the organic photochromic material-polymer composite film layer and the organic semiconductor layer; the organic photochromic material-polymer composite film layer serves as a dielectric layer, and when the device is working, when it is irradiated with ultraviolet light, the properties such as the structure of the organic photochromic material change, and the polymer acts as a dielectric, so that the composite film can store charges, so that the transmission current between the upper electrode groups changes, while under light with a wavelength greater than ultraviolet light or in dark conditions, the current does not change, such as Figure 2 As shown, the change of the channel current between the upper electrodes corresponds to the ultraviolet radiation dose one by one, which can directly reflect the cumulative amount of ultraviolet radiation; the ultraviolet radiation dose monitor described in the present invention has a small size, a simple structure, and low power consumption, and a single device can directly monitor the ultraviolet radiation dose.

[0046] like Figure 3 As shown, the present invention also provides a method for preparing an ultraviolet radiation dose monitor, comprising:

[0047] cleaning the substrate;

[0048] preparing a lower electrode on the substrate;

[0049] preparing an insulating layer on the lower electrode;

[0050] preparing an organic photochromic material-polymer composite film layer on the insulating layer;

[0051] preparing an organic semiconductor thin film on the organic photochromic material-polymer composite film layer;

[0052] A group of upper electrodes is prepared on the organic semiconductor film, wherein the group of upper electrodes comprises a first electrode and a second electrode, and the lower surface of the second electrode is tightly connected to the lower electrode and the upper surface of the organic semiconductor layer respectively.

[0053] Based on the above embodiments, this embodiment further describes the preparation method of the ultraviolet radiation dose monitor in detail, as follows:

[0054] The flexible substrate was ultrasonically cleaned in acetone, isopropanol, anhydrous ethanol and deionized water for fifteen minutes each, and then dried with high-purity nitrogen;

[0055] Prepare gold, aluminum or copper metal thin film as the lower electrode by thermal evaporation, electron beam evaporation or magnetron sputtering, and prepare ITO transparent electrode by magnetron sputtering;

[0056] A 50-200 nm thick parylene, aluminum oxide or silicon oxide film is prepared by magnetron sputtering or atomic layer deposition, or an organic material or inorganic material film is spin-coated by a solution method as an insulating layer, wherein the insulating layer should not completely cover the lower electrode;

[0057] Using toluene as solvent, 2 mg / ml of spiropyran (SP) solution of photochromic material and 10 mg / ml of poly(2-vinylnaphthalene) (PVN) solution of polymer electret material were prepared respectively, and then they were fully mixed in equal volumes, and then the mixed solution was spin-coated on a substrate, and annealed on a heating table at 100°C for 30 minutes to obtain an organic photochromic material-polymer composite film layer;

[0058] A pentacene or carbon 60 small molecule semiconductor film with a thickness of about 30-80 nm is evaporated by thermal evaporation equipment as an organic semiconductor film layer, and a polymer semiconductor such as a P3HT film can also be spin-coated.

[0059] A 50-200 nm gold or copper metal film is deposited by thermal evaporation, and a graphene or silver electrode can also be prepared by printing to obtain an upper electrode group.

[0060] The new flexible wearable electronic ultraviolet radiation dose monitor provided by the present invention can monitor ultraviolet radiation while having the characteristics of small size, high precision, low cost, low power consumption, simple preparation process and device structure, and flexibility and bendability. The new flexible wearable electronic ultraviolet radiation dose monitor provided by the present invention can record ultraviolet radiation dose in a personalized manner, provide users with more accurate reference information to prevent damage from excessive ultraviolet rays, and is of great significance to protecting personal life and health.

[0061] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A UV radiation dose monitor, characterized in that: include: A flexible substrate layer; A lower electrode, firmly connected to the upper surface of the flexible substrate layer, for controlling the electric field in the organic semiconductor layer and the insulating layer; The insulating layer is firmly connected to the upper surface of the lower electrode, the area of ​​the insulating layer is smaller than the area of ​​the lower electrode, and the insulating layer is used to block the connection between the lower electrode and the organic photochromic material-polymer composite film layer; The organic photochromic material-polymer composite film layer is firmly connected to the upper surface of the insulating layer. The organic photochromic material-polymer composite film layer acts as a dielectric layer and stores electric charge when exposed to ultraviolet light, so that the transmission current between the upper electrode groups changes. However, the current does not change under light with a wavelength greater than ultraviolet light or in dark conditions. The organic semiconductor layer is firmly connected to the upper surface of the organic photochromic material-polymer composite film layer, and is used to control the flow of carriers to generate an adjustable and variable current; The upper electrode group includes a first upper electrode and a second upper electrode, wherein the first upper electrode is firmly connected to the upper surface of the organic semiconductor layer, and the lower surface of the second upper electrode is firmly connected to the lower electrode and the upper surface of the organic semiconductor layer, respectively. The upper electrode group is used to control the electric field of the organic photochromic material-polymer composite film layer and the organic semiconductor layer.

2. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The composite material of the organic photochromic material and the polymer is a spiropyran-poly (2-vinylnaphthalene) composite film material.

3. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The flexible substrate layer is one of PET, PI, PEN or a heavily doped silicon wafer with a silicon oxide layer.

4. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The lower electrode is one of gold, aluminum, copper metal films, an ITO transparent electrode or graphene.

5. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The insulating layer is a parylene, aluminum oxide or silicon oxide film.

6. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The insulating layer is a thin film of organic material or inorganic material.

7. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The organic semiconductor layer is pentacene, a carbon small molecule semiconductor material or a polymer semiconductor.

8. The ultraviolet radiation dose monitor according to claim 1, characterized in that: The upper electrode group is made of gold or copper.

9. A method for preparing an ultraviolet radiation dose monitor, characterized in that: include: cleaning the substrate; preparing a lower electrode on the substrate; preparing an insulating layer on the lower electrode; preparing an organic photochromic material-polymer composite film layer on the insulating layer; preparing an organic semiconductor thin film on the organic photochromic material-polymer composite film layer; A group of upper electrodes is prepared on the organic semiconductor film, wherein the group of upper electrodes comprises a first electrode and a second electrode, and the lower surface of the second electrode is tightly connected to the lower electrode and the upper surface of the organic semiconductor layer respectively.

10. The method for preparing an ultraviolet radiation dose monitor according to claim 9, characterized in that: The cleaning substrate comprises: The flexible substrate was ultrasonically cleaned in acetone, isopropanol, anhydrous ethanol and deionized water for fifteen minutes each, and then dried with high-purity nitrogen.

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