An energetic diode applied to self-destruction chip and a preparation method thereof

Abstract

The application belongs to the field of self-destruction chip, and particularly relates to an energetic diode applied to a self-destruction chip and a preparation method thereof. The energetic diode comprises bottom material, intermediate layer material and top material arranged in sequence; the bottom material and the intermediate layer material form an energetic material area of the aluminum thermite type, the intermediate layer material and the top material form a semiconductor material area, that is, the intermediate layer material and the top material form a P-N junction; the intermediate layer material is one or a combination of any of the oxidants of the metal oxide type in the aluminum thermite, and the metal oxide constituting the intermediate layer material is a same type of semiconductor material. The application combines the semiconductor material and the energetic material to prepare the energetic diode with dual functions of logic and energy, so that the chip can realize the conventional function and release energy to complete the chip self-destruction under the predetermined condition, and the purpose of protecting the chip is achieved.

Description

Technical Field

[0001] This invention belongs to the field of self-destructing chips, specifically relating to an energetic diode used in self-destructing chips and its fabrication method. Background Technology

[0002] To prevent information leakage, we want devices or information to be structurally destroyed and destroyed under predefined conditions; this mechanism is called self-destruction. Chips with self-destruct mechanisms can undergo physical or chemical self-destruction under predefined conditions, protecting the information carried and transmitted by the chip, while also preventing the leakage of important internal circuit designs.

[0003] There are currently four main methods for chip self-destruction mechanisms: transient electronics, stress degradation, chemical etching, and energetic material destruction. Transient electronics uses biodegradable metals, polymers, and semiconductors as the main materials. When triggered by heat, light, or solutions, the materials can self-destruct completely. This technology is highly compatible with flexible electronics, but it heavily relies on micro / nano materials and has a low instantaneous response time. Stress degradation introduces stress into the device structure and, under certain control, amplifies the stress to damage the device's microstructure, causing it to lose function. This technology is highly secure and compatible with chip manufacturing processes, but the challenge lies in the complex design of the microstructure and process conditions. Chemical etching involves designing a microcavity structure within the device and filling it with a chemical etchant. The solution is released by breaking down the cavity walls, thus destroying the chip. While the principle is simple, the design and fabrication of the liquid storage cavity are complex, and the stable storage of the chemical etchant within the cavity is difficult to achieve. Energetic material destruction involves adding energetic materials to the device. A chemical reaction within the energetic material releases a large amount of heat energy, thereby destroying the device. This method is highly destructive, but it is difficult to find a suitable energetic material system that can simultaneously achieve both exothermic performance and safety.

[0004] However, all of the above methods have drawbacks. Some methods can only be used for specially constructed chips, and they are not fully adaptable to integrated semiconductor (CMOS) and integrated circuit (IC) manufacturing processes and technologies. Energetic material damage requires additional excitation modules, adding steps to the chip manufacturing process and making large-scale mass production impossible, thus increasing the difficulty of chip manufacturing. Furthermore, energetic material damage is not universally applicable; some extremely sensitive circuits cannot find energetic material systems that balance heat dissipation performance and safety. The safety of energetic materials in energetic material damage methods still needs improvement. Currently, there is no method that is universally applicable, structurally simple, and has good self-destruction performance. Summary of the Invention

[0005] The purpose of this invention is to provide an energetic diode that combines logic and energy, enabling the chip to perform conventional functions and release a large amount of energy to complete the chip's self-destruction upon activation.

[0006] The technical solution to achieve the purpose of this invention is: an energetic diode for a self-destructing chip, comprising a bottom layer material, an intermediate layer material and a top layer material arranged sequentially;

[0007] The bottom layer material and the middle layer material constitute the energetic material region of the thermite type, and the middle layer material and the top layer material constitute the semiconductor material region, that is, the middle layer material and the top layer material form a PN junction;

[0008] The intermediate layer material is one or a combination of several metal oxide-type oxidants in the thermite, and the metal oxides constituting the intermediate layer material are semiconductor materials of the same type.

[0009] Furthermore, the underlying material is one or more of the reducing agent components in the thermite.

[0010] Furthermore, the underlying material is one or a mixture of several of Al, Mg, B, and Be.

[0011] Furthermore, the intermediate layer material is Cu. x O, Fe x O y Cr x O y One or a mixture of several of the following: NiO, Bi2O3, MoO3, SnO, SnO2, and TiO2.

[0012] Furthermore, why is the top layer material a relative type of metal semiconductor oxide compared to the middle layer material?

[0013] Furthermore, the top layer material is a metal semiconductor oxide such as ZnO, TiO2, Al2O3, or Cu. x O, Fe x O y Cr x O y One or a mixture of several of NiO, Bi2O3, MoO3, SnO, and SnO2.

[0014] Furthermore, it also includes a top electrode disposed on the top layer material;

[0015] Preferably, the top electrode is one of gold plating, silver plating, silver paste, or metal mesh;

[0016] Preferably, the top electrode is made of molybdenum mesh.

[0017] Furthermore, when the conductivity of the underlying material cannot meet the requirements of the electrode, a bottom electrode is set outside the underlying material.

[0018] Furthermore, the substrate is prepared by sequential epitaxial growth of three layers of material, using methods such as hydrothermal method, sol-gel, magnetron sputtering, vapor phase physical deposition, electrochemical deposition, or laser pulse deposition.

[0019] A method for fabricating an Al / CuO / ZnO energetic diode includes the following steps:

[0020] Step (1): Polish the aluminum sheet and rinse it with ethanol and deionized water for later use;

[0021] Step (2): Dissolve copper nitrate and sodium nitrate in water to obtain the first step electrochemical deposition electrolyte. The aluminum sheet obtained in step (1) is used as the anode and the platinum electrode is used as the cathode. Electrochemically deposit CuO film under constant voltage conditions.

[0022] Step (3): Take out the aluminum sheet that has been electrochemically deposited in step (2) and put it into a muffle furnace for annealing to obtain an aluminum sheet with a CuO film;

[0023] Step (4): Dissolve zinc nitrate and sodium nitrate in water to obtain the second step electrochemical deposition electrolyte. The aluminum sheet with CuO film obtained in step (3) is used as the anode and the platinum electrode is used as the cathode. The ZnO film is electrochemically deposited under constant current conditions by water bath heating.

[0024] Step (5): Take out the aluminum sheet that has been electrochemically deposited in step (4), put it in an oven to dry, and then attach a top electrode on the ZnO thin film to obtain a ZnO-CuO-Al energetic diode.

[0025] Furthermore, in step (2), copper sulfate or copper acetate is used instead of copper nitrate, and potassium nitrate is used instead of sodium nitrate; in step (4), potassium nitrate is used instead of sodium nitrate.

[0026] Preferably, the thickness of the aluminum sheet is 50–200 micrometers;

[0027] Preferably, in step (2), the molar ratio of copper nitrate to sodium nitrate is in the range of 1:1 to 3:1; the constant voltage is 2.0 to 2.2V; and the deposition time is 600 to 900s.

[0028] Preferably, in step (3), the annealing heating rate in the muffle furnace is 4-8℃ / min, and the temperature is held at 350-450℃ for 3-5 hours;

[0029] Preferably, in step (4), the molar ratio of zinc nitrate to sodium nitrate is 4:1 to 6:1; the water bath heating temperature is 60 to 70°C; the constant current is 0.05 to 0.10A; and the deposition time is 420 to 600 seconds.

[0030] Preferably, in step (5), the oven temperature is 90-110°C and the time is 1-1.5 hours.

[0031] Compared with the prior art, the significant advantages of this invention are:

[0032] (1) This invention designs a layered structure that ingeniously combines semiconductor materials and energetic materials to fabricate an energetic diode with both logic and energy functions. The entire structure consists of a semiconductor material region and an energetic material region. A widely studied aluminothermic material is selected as the energetic material to provide energy to the energetic diode. The layered structure is mainly composed of three materials, the most noteworthy of which is the intermediate layer material that acts as a bridge. The intermediate layer material is a metal oxide, which not only acts as an aluminothermic oxidant component and can undergo an aluminothermic reaction with the aluminothermic reducing component at the bottom to provide energy to the energetic diode, but also, because it is a metal oxide, belongs to the field of semiconductor materials and can form a PN junction with different types of semiconductor materials at the top, enabling the energetic diode to have logic functions. Therefore, it has both logic and energy functions, possessing dual functions; it can realize the conventional functions of the chip while releasing energy to complete the chip self-destruction under predetermined conditions, thus achieving the purpose of protecting the chip.

[0033] (2) The structure of the energetic diode designed in this invention is simple, and the destruction is fast and precise; the preparation method is fully applicable to the MEMS chip manufacturing process, and it can be used as an additional electronic component without adding steps in chip manufacturing. It can be mass-produced as an electronic device and has universality; it is safe, simple and has low production cost.

[0034] (3) This invention perfectly combines diodes and energetic materials, and the device prepared meets the application requirements and has extremely high innovation and practical value. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the energetic diode described in this invention.

[0036] Figure 2 This is a schematic diagram of the basic structure of the energetic diode described in this invention.

[0037] Figure 3 This is a flowchart illustrating the fabrication process of the Al / CuO / ZnO energetic diode described in this invention.

[0038] Figure 4 This is a SEM image of the cross-section of Al / CuO / ZnO prepared in Example 1 of the present invention.

[0039] Figure 5 High-speed photographic image of the Al / CuO / ZnO energetic diode prepared in Example 1 of this invention for energy performance testing.

[0040] Explanation of reference numerals in the attached figures:

[0041] 11-Bottom thermite component material, 12-Intermediate layer material, 13-Metal oxide semiconductor material, 14-Top electrode. Detailed Implementation

[0042] The present invention will now be described in further detail with reference to the accompanying drawings.

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0044] The following provides a detailed description. In the description of this application, the term "comprising" means "including but not limited to". Embodiments in this application may exist in the form of a range. It should be understood that the description in the form of a range is only for convenience and brevity and should not be construed as a rigid limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, this application provides an embodiment with a range value of 350–450°C. It should be considered that the range description of 350–450°C has specifically disclosed sub-ranges, such as 350–450°C, 350–400°C, 400–450°C, 350–375°C, 350–390°C, etc., and single numerical values ​​within that range, such as 360°C, 375°C, 425°C, 415°C, etc. Furthermore, whenever a numerical range is given herein, it means that any referable numerical value (fraction and integer) within the indicated range is included; this principle applies regardless of the range. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of this patent.

[0045] The thermite system has been extensively and thoroughly studied in the field of energetic materials and is a typical energetic system. Therefore, the energetic diode designed in this invention uses the thermite system as the energetic material system, and cleverly integrates the semiconductor material and the thermite system through a suitable structure.

[0046] like Figure 1-2As shown, an energetic diode possesses both logic and energy properties. The entire energetic diode has a layered structure, mainly divided into an energetic material region and a semiconductor material region. The bottom material is one or more mixtures of the reducing agent components in the aluminothermic agent; the middle layer material is one or more mixtures of the oxidizing agent components in the aluminothermic agent. Because it is a metal oxide and also belongs to the semiconductor field, it acts as a bridge connecting the energetic region and the semiconductor region. Therefore, the middle layer material belongs to both the energetic material region and the semiconductor material region; the top material is one or more mixtures of semiconductor materials. The selection should be based on the type of the middle layer material. If the middle layer material is a P-type semiconductor, then the top material should be an N-type semiconductor, and vice versa. Because the top material is a semiconductor material, a top electrode needs to be added when forming the energetic diode device. In addition, when the reducing component in the aluminothermic agent used as the bottom material has poor conductivity, a bottom electrode also needs to be added to facilitate the normal operation of the energetic diode device. When the energetic diode device is connected to the circuit, the current starts from the bottom, passes through the middle layer and the top layer, and reaches the top electrode, forming a current loop. Under normal circumstances, the semiconductor region of an energetic diode, namely the middle layer and the top layer material, forms a PN junction, giving the energetic diode logic and enabling it to perform conventional logic functions as a basic diode electronic component. Under predefined conditions and given a certain stimulus, the energetic diode can be excited, converting electrical energy into heat energy, thereby stimulating the aluminothermic reaction of the aluminothermic components, releasing a large amount of energy and destroying the energetic diode device; at the same time, it causes a surge in current in the circuit, destroying the chip.

[0047] The bottom material of the energetic material region can be one or more mixed components selected from Al, Mg, B, and Be;

[0048] The intermediate layer material is Cu x O, Fe x O y Cr x O y One or more mixed components selected from NiO, Bi2O3, MoO3, SnO, SnO2, and TiO2;

[0049] The topmost metal semiconductor oxide in the semiconductor region can be ZnO, TiO2, Al2O3, or Cu. x O, Fe x O y Cr x O y One of NiO, Bi2O3, MoO3, SnO, SnO2, or a mixture of or more of the above elements;

[0050] The fabrication principle of energetic diode devices involves the sequential epitaxial growth of three main layers of material on a substrate. Epitaxial methods can include hydrothermal deposition, sol-gel deposition, magnetron sputtering, vapor phase physical deposition, electrochemical deposition, and laser pulse deposition. To better understand the energetic diode described in this invention, a method for fabricating an Al / CuO / ZnO energetic diode is provided herein.

[0051] Reference Figure 3 The diagram shown is a flowchart of the fabrication process of the Al / CuO / ZnO energetic diode device according to an embodiment of this invention. It employs a simple two-step electrochemical deposition method, and the fabrication steps include:

[0052] Step 1: Polish the aluminum sheet and rinse it with ethanol and deionized water for later use.

[0053] Step 2: Dissolve copper nitrate and sodium nitrate in water to obtain the electrolyte for the first step of electrochemical deposition. The aluminum sheet prepared in step 1 is used as the anode and the platinum electrode is used as the cathode. Electrochemically deposit a CuO film under constant voltage conditions.

[0054] Step 3: Take out the aluminum sheet that has been electrochemically deposited in Step 2 and put it into a muffle furnace for annealing to obtain an aluminum sheet with a CuO film.

[0055] Step 4: Dissolve zinc nitrate and sodium nitrate in water to obtain the electrolyte for the second step of electrochemical deposition. The aluminum sheet with CuO film that has been annealed in step 3 is used as the anode, and the platinum electrode is used as the cathode. The ZnO film is electrochemically deposited under constant current conditions by water bath heating.

[0056] Step 5: Take out the aluminum sheet that has been electrochemically deposited in Step 4 and put it into an oven to obtain the basic structure of an energetic diode, ZnO-CuO-Al.

[0057] Optionally, in step two, copper nitrate in electrolyte A can be replaced by copper sulfate, copper acetate, or other copper-containing cation solutions; sodium nitrate can be replaced by potassium nitrate; and in step four, sodium nitrate in electrolyte B can be replaced by potassium nitrate.

[0058] Optionally, the bottom substrate is an aluminum sheet with a thickness of 50 to 200 micrometers;

[0059] Preferably, in step two, the molar ratio of copper nitrate to sodium nitrate in electrolyte A is in the range of 1:1 to 3:1; the constant voltage range is 2.0 to 2.2V; and the deposition time range is 600 to 900s.

[0060] Preferably, in step three, the annealing heating rate in the muffle furnace is 4-8°C / min, and the temperature is held at 350-450°C for 3-5 hours.

[0061] Preferably, in step four, the molar ratio of zinc nitrate to sodium nitrate in electrolyte B is in the range of 4:1 to 6:1; the water bath heating temperature is in the range of 60 to 70°C; the constant current is in the range of 0.05 to 0.10A; and the deposition time is in the range of 420s to 600s.

[0062] Preferably, in step five, the oven temperature is 90–110°C and the time is 1–1.5 hours.

[0063] Furthermore, the method for fabricating this energetic diode device includes:

[0064] In order to enable the basic structure of Al / CuO / ZnO energetic diodes to be connected to circuits for a series of tests, the bottom layer of aluminum metal is used as a natural bottom electrode, and a top electrode is added to obtain an Al / CuO / ZnO energetic diode device.

[0065] Optionally, the top electrode can be made of one of the following: gold plating, silver plating, silver paste, or metal mesh.

[0066] Preferably, the top electrode is made of molybdenum mesh;

[0067] Example 1

[0068] Step 1: Polish the 100-micron-thick aluminum sheet with sandpaper, rinse it with anhydrous ethanol, and then rinse it with deionized water for later use.

[0069] Step 2: Dissolve copper nitrate (0.3M) in water to obtain the electrolyte for the first step of electrochemical deposition. The aluminum sheet prepared in step 1 is used as the anode and the platinum electrode is used as the cathode. Electrochemical deposition is performed at a constant voltage of 2.0V for 900s.

[0070] Step 3: Take out the aluminum sheet that has been electrochemically deposited in Step 2, and anneal it in a muffle furnace at 400°C for 4 hours to obtain an aluminum sheet with a CuO film.

[0071] Step 4: Dissolve zinc nitrate (0.5M) in water to obtain the electrolyte for the second step of electrochemical deposition. The aluminum sheet with CuO film that has been annealed in step 3 is used as the anode, and the platinum electrode is used as the cathode. The electrochemical deposition is carried out at a constant current of 0.10A for 420s in a water bath at 65℃.

[0072] Step 5: Take out the aluminum sheet that has been electrochemically deposited in Step 4 and put it in a 100℃ oven for 1 hour to obtain the basic structure of an energetic diode with ZnO-CuO-Al.

[0073] We performed XRD and SEM tests on the basic structure of the ZnO-CuO-Al energetic diode. XRD analysis confirmed the successful fabrication of the ZnO-CuO-Al basic structure. After adding a Mo mesh as the top electrode, we conducted IV curve and energy dispersive testing on the ZnO-CuO-Al energetic diode device. IV curve analysis demonstrated that the ZnO-CuO-Al energetic diode exhibits unidirectional conductivity, i.e., logic conductivity; energy dispersive testing confirmed that the ZnO-CuO-Al energetic diode can release energy under certain stimuli. Figure 4 This is a cross-sectional SEM image of the Al / CuO / ZnO basic structure prepared in Example 1 of the present invention. Figure 5 High-speed photographic image of the Al / CuO / ZnO energetic diode prepared in Example 1 of this invention for energy performance testing.

[0074] Example 2

[0075] Step 1: Polish the 100-micron-thick aluminum sheet with sandpaper, rinse it with anhydrous ethanol, and then rinse it with deionized water for later use.

[0076] Step 2: Dissolve copper nitrate (0.3M) and sodium nitrate (0.1M) in water to obtain the electrolyte for the first step of electrochemical deposition. The aluminum sheet prepared in step 1 is used as the anode and the platinum electrode is used as the cathode. Electrochemical deposition is performed at a constant voltage of 2.0V for 900s.

[0077] Step 3: Take out the aluminum sheet that has been electrochemically deposited in Step 2, and anneal it in a muffle furnace at 400°C for 4 hours to obtain an aluminum sheet with a CuO film.

[0078] Step 4: Dissolve zinc nitrate (0.5M) and sodium nitrate (0.1M) in water to obtain the electrolyte for the second step of electrochemical deposition. The aluminum sheet with CuO film that has been annealed in step 3 is used as the anode, and the platinum electrode is used as the cathode. The electrochemical deposition is carried out at a constant current of 0.10A for 420s in a water bath at 65℃.

[0079] Step 5: Take out the aluminum sheet that has been electrochemically deposited in Step 4 and put it in a 100℃ oven for 1 hour to obtain the basic structure of an energetic diode with ZnO-CuO-Al.

[0080] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An energetic diode for use in self-destructing chips, characterized in that, This includes the bottom layer material, the middle layer material, and the top layer material arranged sequentially; The bottom layer material and the middle layer material constitute the energetic material region of the thermite type, and the middle layer material and the top layer material constitute the semiconductor material region, that is, the middle layer material and the top layer material form a PN junction; The intermediate layer material is one or a combination of several metal oxide-type oxidants in the thermite, and the metal oxides constituting the intermediate layer material are semiconductor materials of the same conductivity type.

2. The energetic diode according to claim 1, characterized in that, The bottom material is one or more of the reducing agent components in the thermite.

3. The energetic diode according to claim 2, characterized in that, The underlying material is one or a mixture of several of Al, Mg, B, and Be.

4. The energetic diode according to claim 2, characterized in that, The intermediate layer material is Cu x O, Fe x O y Cr x O y One or a mixture of several of the following: NiO, Bi2O3, MoO3, SnO, SnO2, and TiO2.

5. The energetic diode according to claim 4, characterized in that, The top layer material is a metal semiconductor oxide with a conductivity type opposite to that of the middle layer material.

6. The energetic diode according to claim 5, characterized in that, The top layer material is a metal semiconductor oxide, such as ZnO, TiO2, Al2O3, or Cu. x O, Fe x O y Cr x O y One or a mixture of several of NiO, Bi2O3, MoO3, SnO, and SnO2.

7. The energetic diode according to claim 1, characterized in that, It also includes a top electrode disposed on the top layer material.

8. The energetic diode according to claim 7, characterized in that, The top electrode is made of one of the following: gold plating, silver plating, silver paste, or metal mesh.

9. The energetic diode according to claim 8, characterized in that, The top electrode is made of molybdenum mesh.

10. The energetic diode according to claim 1, characterized in that, When the conductivity of the underlying material cannot meet the requirements of the electrode, a bottom electrode is set outside the underlying material.

11. The energetic diode according to any one of claims 1-10, characterized in that, The substrate is prepared by sequential epitaxial growth of three main layers of materials. The epitaxial methods include hydrothermal method, sol-gel, magnetron sputtering, vapor phase physical deposition, electrochemical deposition or laser pulse deposition.

12. A method for fabricating an Al / CuO / ZnO energetic diode, characterized in that, Includes the following steps: Step (1): Polish the aluminum sheet and rinse it with ethanol and deionized water for later use; Step (2): Dissolve copper nitrate and sodium nitrate in water to obtain the first step electrochemical deposition electrolyte. The aluminum sheet obtained in step (1) is used as the anode and the platinum electrode is used as the cathode. Electrochemically deposit CuO film under constant voltage conditions. Step (3): Take out the aluminum sheet that has been electrochemically deposited in step (2) and put it into a muffle furnace for annealing to obtain an aluminum sheet with a CuO film; Step (4): Dissolve zinc nitrate and sodium nitrate in water to obtain the second step electrochemical deposition electrolyte. The aluminum sheet with CuO film obtained in step (3) is used as the anode and the platinum electrode is used as the cathode. The ZnO film is electrochemically deposited under constant current conditions by water bath heating. Step (5): Take out the aluminum sheet that has been electrochemically deposited in step (4), put it in an oven to dry, and then attach a top electrode on the ZnO film to obtain a ZnO-CuO-Al energetic diode.

13. The method according to claim 12, characterized in that, In step (2), copper sulfate or copper acetate is used instead of copper nitrate, and potassium nitrate is used instead of sodium nitrate; in step (4), potassium nitrate is used instead of sodium nitrate.

14. The method according to claim 12, characterized in that, The thickness of the aluminum sheet is 50~200 micrometers.

15. The method according to claim 12, characterized in that, In step (2), the molar ratio of copper nitrate to sodium nitrate is 1:1 to 3:1; the constant voltage is 2.0 to 2.2V; and the deposition time is 600 to 900s.

16. The method according to claim 12, characterized in that, In step (3), the annealing heating rate in the muffle furnace is 4~8℃ / min, and the temperature is held at 350~450℃ for 3~5 hours.

17. The method according to claim 12, characterized in that, In step (4), the molar ratio of zinc nitrate to sodium nitrate is 4:1 to 6:1; the water bath heating temperature is 60 to 70°C; the constant current is 0.05 to 0.10A; and the deposition time is 420 to 600 seconds.

18. The method according to claim 12, characterized in that, In step (5), the oven temperature is 90~110℃ and the time is 1~1.5 hours.

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