Packaging structure for self-destruction of passive silicon-based device based on hydrolytic ceramic

Abstract

This invention belongs to the field of semiconductor technology and discloses a packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics. The structure includes a housing, a base, and a self-destruct component. The bottom of the housing is fixedly connected to the base, forming a first chamber for encapsulating the silicon-based device. A mounting groove for accommodating the self-destruct component is formed on the top of the housing, located above and communicating with the first chamber. The self-destruct component includes a low-hydrolysis ceramic cover plate, a high-hydrolysis ceramic cover plate A, and an etchant for destroying the silicon-based device. The low-hydrolysis ceramic cover plate is fixedly connected to the top of the mounting groove. The high-hydrolysis ceramic cover plate A is fixedly connected to the inner side of the mounting groove or the bottom of the low-hydrolysis ceramic cover plate. A chamber for accommodating the etchant is formed between the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A. The thickness hydrolysis rate of the low-hydrolysis ceramic cover plate is less than that of the high-hydrolysis ceramic cover plate A. This invention can destroy the encapsulated silicon-based device without a power supply and has wide applicability.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, and relates to information security and special packaging materials for semiconductor devices. It relates to a special ceramic packaging structure for packaging silicon-based microdevices such as chips and microelectromechanical devices, and particularly to a packaging structure based on hydrolytic ceramics to achieve self-destruction of passive silicon-based devices. Background Technology

[0002] Silicon-based semiconductor chips (i.e., silicon-based devices, such as Flash memory chips and DRAM memory chips) and microelectromechanical systems (MEMS) are the hardware foundation supporting the rapid development of information technology and industry. These semiconductor devices are widely used in information acquisition, analysis, storage, and transmission. However, they inevitably involve the storage and encryption of large amounts of sensitive information. If information terminal devices integrating these functional chips are lost or stolen, important information or technology within the chips may be stolen or leaked. Therefore, self-destruct functions are often added to these critical core components during product planning and design to ensure rapid destruction in emergencies and protect information from leakage.

[0003] Currently, most self-destruct components for silicon-based devices employ active designs, such as high-pulse current impact methods and secondary excitation combustion reactions. However, these self-destruct components all require a power supply. For certain passive devices without a power source, or non-recyclable devices that need to operate until the power supply is exhausted, there are currently no targeted self-destruct components.

[0004] Therefore, designing a self-destruct component for passive silicon-based devices is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned technical problems and provide a packaging structure based on hydrolytic ceramics to achieve self-destruction of passive silicon-based devices. This packaging structure can destroy the silicon-based devices encapsulated in the housing when there is no power.

[0006] The technical solution adopted in this invention is: a packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics, including a shell, a base and a self-destruction component;

[0007] The bottom of the housing is fixedly connected to the base, forming a first chamber for encapsulating silicon-based devices. The top of the housing has a mounting groove for accommodating a self-destruct component. The mounting groove is located above the first chamber and is connected to it. The self-destruct component includes a low-hydrolysis ceramic cover plate, a high-hydrolysis ceramic cover plate A, and an etchant for destroying the silicon-based devices. The low-hydrolysis ceramic cover plate is fixedly connected to the top of the mounting groove. The high-hydrolysis ceramic cover plate A is fixedly connected to the inner side of the mounting groove or the bottom of the low-hydrolysis ceramic cover plate. A second chamber for accommodating the etchant is formed between the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A. The thickness hydrolysis rate of the low-hydrolysis ceramic cover plate is less than that of the high-hydrolysis ceramic cover plate A.

[0008] In one possible implementation, the thickness hydrolysis rate of the low-hydrolysis ceramic cover plate is less than 1 mm / d, preferably 0.1-1 mm / d; the thickness hydrolysis rate of the high-hydrolysis ceramic cover plate is 4-10 mm / h.

[0009] Furthermore, both the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A are borosilicate ceramics with the chemical formula aB2O3·bSiO2·cAl2O3·dXO, where a, b, c, and d are mass percentages, a+b+c+d=1; XO is a metal oxide, and X is Ba, Ca, or Mg.

[0010] For low-hydrolysis ceramic covers, 10%≤a≤15%, 40%≤b≤50%, 30%≤c≤40%, and 5%≤d≤10%;

[0011] For high-hydrolysis ceramic cover plate A, 30% ≤ a ≤ 50%, 20% ≤ b ≤ 35%, 20% ≤ c ≤ 30%, and 0% ≤ d ≤ 5%.

[0012] In one possible implementation, the etchant is preferably a strongly alkaline solid etchant; preferably one of NaOH, KOH, etc.; since the etching rate of KOH solution is about 1 μm / min, it can completely destroy the functional layer of the chip in a few minutes, therefore, more preferably, the etchant is KOH. A cross-sectional image of a silicon wafer array after etching with a 20% KOH solution at 40°C for 10 minutes is shown below. Figure 1 As shown in the figure, the silicon wafer surface has been etched to a depth of about 3.5 micrometers, which essentially causes the silicon-based device to fail.

[0013] In one possible implementation, the self-destruct component further includes a heating agent; the heating agent and the corrosive agent are placed in a stacked or horizontal manner, specifically configured as follows:

[0014] When the exothermic agent and corrosive agent are stacked, the self-destruct component also includes a high-hydrolysis ceramic cover plate B; the high-hydrolysis ceramic cover plate B has the same composition as the high-hydrolysis ceramic cover plate A; the high-hydrolysis ceramic cover plate B is disposed below the high-hydrolysis ceramic cover plate A and is fixedly connected to the inner side of the mounting groove; the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A form a third chamber for containing the exothermic agent; a second chamber for containing the corrosive agent is formed between the high-hydrolysis ceramic cover plate A and the high-hydrolysis ceramic cover plate B;

[0015] More specifically, the inner side of the mounting groove is provided with stepped grooves for placing low-hydrolysis ceramic cover plates, high-hydrolysis ceramic cover plate A, and high-hydrolysis ceramic cover plate B. The low-hydrolysis ceramic cover plates, high-hydrolysis ceramic cover plate A, and high-hydrolysis ceramic cover plate B are fixedly connected to the corresponding stepped grooves by sealant. The top surface of the low-hydrolysis ceramic cover plate is flush with the top surface of the shell.

[0016] When the exothermic agent and the corrosive agent are placed horizontally, the high-hydrolysis ceramic cover plate A forms an upwardly protruding partition; the partition divides the chamber formed by the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A into two independent third chambers that respectively contain the exothermic agent and a second chamber that contains the corrosive agent.

[0017] More specifically, the low-hydrolysis ceramic cover plate has a groove at the bottom; the outer edge of the high-hydrolysis ceramic cover plate A is fixedly connected to the inner side of the groove of the low-hydrolysis ceramic cover plate by sealant, and is placed on the stepped groove opened inside the mounting groove as a whole, and further fixed by sealant. The top surface of the low-hydrolysis ceramic cover plate is flush with the top surface of the shell.

[0018] The heating agent is used to release heat, which can accelerate the corrosion rate of the highly hydrolyzable ceramic cover plate and also accelerate the corrosion rate of silicon-based devices by the etchant. This invention uses a solid heating agent, preferably CaO or nano-aluminum powder.

[0019] Furthermore, both the heating agent and the corrosive agent are in block form, obtained by pressing the corresponding raw materials.

[0020] In one possible implementation, the preparation steps of the low-hydrolysis ceramic cover plate are as follows:

[0021] (1) Weigh the raw materials kaolin, the compound containing X and boric acid according to the chemical composition of the low hydrolysis ceramic cover plate;

[0022] (2) Crush the kaolin and the compound containing X, and then ball mill them into a slurry using deionized water;

[0023] (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 300-400℃ for 3-6 hours to make ceramic pre-fired powder;

[0024] (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again;

[0025] (5) The slurry is cast into sheets and pressed into a pre-formed low-hydrolysis ceramic cover plate with a preset structure.

[0026] (6) Sinter the pre-formed low-hydrolysis ceramic cover plate at 500-600℃ for 1-2 hours, and then heat it to 950-1050℃ and continue sintering for 2-3 hours to obtain the final low-hydrolysis ceramic cover plate.

[0027] In one possible implementation, the preparation steps of the highly hydrolyzed ceramic cover plate A or the highly hydrolyzed ceramic cover plate B are as follows:

[0028] (1′) Weigh the raw materials kaolin, the compound containing X and boric acid according to the chemical composition of the high-hydrolysis ceramic cover plate A or the high-hydrolysis ceramic cover plate B;

[0029] (2′) Crush the kaolin and the X-containing compound, and then ball mill them into a slurry using deionized water in a ball mill;

[0030] (3′) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 300-400℃ for 3-6 hours to make ceramic pre-fired powder;

[0031] (4′) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again;

[0032] (5′) The slurry is cast into sheets and pressed into a preset structure to obtain a pre-formed high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B;

[0033] (6′) Sinter the pre-formed high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B at 500-600℃ for 1-2 hours, and then heat it to 850-950℃ and continue sintering for 0.5-1 hours to obtain the final high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B.

[0034] The compounds containing X mentioned above are their oxides, salts, or hydroxides.

[0035] The solid content of the slurry in step (2) or (2′) above is 20%-25%.

[0036] The solid content of the slurry in step (4) or (4′) above is 30%-50%.

[0037] The self-destruction mechanism of the silicon-based device in this invention is as follows: chemical wet etching of the silicon wafer by a strongly alkaline solution. The low-hydrolysis ceramic cover plate hydrolyzes and collapses first, followed by the high-hydrolysis ceramic cover plate. The etchant sealed on the high-hydrolysis ceramic cover plate reacts rapidly with water. The heat released by the added exothermic agent can accelerate the corrosion rate of the silicon-based device and also accelerate the corrosion rate of the high-hydrolysis ceramic cover plate. This allows the high-temperature, high-concentration etchant to rapidly corrode the functional layer of the silicon-based device, causing it to lose its function and thus achieving self-destruction of the silicon-based device.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1) This invention utilizes low-hydrolysis ceramics and high-hydrolysis ceramics, along with corrosives, to construct self-destruct components. It can destroy silicon-based devices using only the most readily available resources in nature, such as light and water. Compared to the various circuits required for the strong pulse current impact method and secondary ignition combustion reaction in existing technologies, the self-destruct components in this invention can destroy the encapsulated silicon-based devices without a power supply. Furthermore, the size of the encapsulation structure can be designed according to the size of the silicon-based devices, resulting in a simple structure with wide applicability.

[0040] 2) The self-destruct component provided in this invention also includes a heating agent. The heat released by the heating agent accelerates the corrosion rate of the corrosive agent, thereby achieving rapid corrosion; it can also accelerate the corrosion rate of the highly hydrolyzed ceramic cover plate. Attached Figure Description

[0041] Figure 1 The image shows a cross-section of a silicon wafer array after being etched by a 20% KOH solution at 40°C for 10 minutes.

[0042] Figure 2 The images show a comparison of the high-hydrolysis ceramic sample with a thickness of 3 mm prepared in Example 3 before and during hydrolysis. (a) is the high-hydrolysis ceramic sample before hydrolysis, and (b) is the high-hydrolysis ceramic sample during hydrolysis.

[0043] Figure 3 This is a schematic diagram of the packaging structure for achieving self-destruction of passive silicon-based devices based on hydrolytic ceramics in Example 7;

[0044] In the figure, 1 is the housing; 11 is the first chamber; 12a is the mounting groove; 121a is the second chamber; 122a is the third chamber; 2 is the silicon-based device; 3 is the low-hydrolysis ceramic cover plate; 4a is the high-hydrolysis ceramic cover plate A; 4b is the high-hydrolysis ceramic cover plate B; 5 is the heating agent; 6 is the corrosive agent; and 7 is the base.

[0045] Figure 4 This is a schematic diagram of the packaging structure for achieving self-destruction of passive silicon-based devices based on hydrolytic ceramics in Example 8;

[0046] In the figure, 1 is the housing; 11 is the first chamber; 12b is the mounting groove; 121b is the second chamber; 122b is the third chamber; 2 is the silicon-based device; 3 is the low-hydrolysis ceramic cover plate; 4c is the high-hydrolysis ceramic cover plate A; 41 is the partition; 5 is the heating agent; 6 is the corrosive agent; and 7 is the base. Detailed Implementation

[0047] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are part of the present invention.

[0048] Example 1

[0049] This embodiment provides a method for preparing low-hydrolysis ceramics, including the following steps:

[0050] (1) Based on the chemical composition of low hydrolysis ceramics aB2O3·bSiO2·cAl2O3·dCaO, weigh the raw materials kaolin (Al2O3·2SiO2·2H2O), quicklime (Ca(OH)2) and boric acid (H3BO3) according to the proportion of a=15%, b=40.6%, c=34.4% and d=10%.

[0051] (2) Crush kaolin and quicklime, and then ball mill them into a slurry using deionized water; the solid content of the slurry is 20%;

[0052] (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 400℃ for 3 hours to make ceramic pre-fired powder;

[0053] (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; the solid content of the slurry is 20%;

[0054] (5) The slurry is dried to remove excess moisture and pressed into shape to obtain low-hydrolysis ceramics;

[0055] (6) The low-hydrolysis ceramic is sintered at 600°C for 1 hour, then heated to 1050°C and sintered for another 2 hours. After that, it is cooled to room temperature in the furnace to obtain the final low-hydrolysis ceramic product.

[0056] Example 2

[0057] This embodiment provides a method for preparing low-hydrolysis ceramics, including the following steps:

[0058] (1) Based on the chemical composition of low hydrolysis ceramics aB2O3·bSiO2·cAl2O3·dMgO, weigh the raw materials kaolin (Al2O3·2SiO2·2H2O), magnesium oxide (MgO) and boric acid (H3BO3) according to the proportion of a=10%, b=46%, c=39% and d=5%.

[0059] (2) Crush kaolin and magnesium oxide and ball mill them into a slurry in a ball mill with deionized water; the solid content of the slurry is 25%;

[0060] (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 300℃ for 6 hours to make ceramic pre-fired powder;

[0061] (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; the solid content of the slurry is 25%;

[0062] (5) The slurry is dried to remove excess moisture and pressed into shape to obtain a low-hydrolysis ceramic sample;

[0063] (6) The pre-formed low-hydrolysis ceramic product is sintered at 500°C for 2 hours, then heated to 950°C and sintered for another 3 hours. After that, it is cooled to room temperature in the furnace to obtain the final low-hydrolysis ceramic.

[0064] Example 3

[0065] This embodiment provides a method for preparing highly hydrolyzable ceramics, including the following steps:

[0066] (1) Based on the chemical composition of the high hydrolysis ceramic aB2O3·bSiO2·cAl2O3·dBaO, weigh the raw materials kaolin (Al2O3·2SiO2·2H2O), barium oxide (BaO) and boric acid (H3BO3) according to the proportion of a=30%, b=35%, c=30% and d=5%.

[0067] (2) Crush kaolin and barium oxide, and ball mill them into a slurry with deionized water in a ball mill; the solid content of the slurry is 20%;

[0068] (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 400℃ for 3 hours to make ceramic pre-fired powder;

[0069] (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; the solid content of the slurry is 20%;

[0070] (5) The slurry is dried to remove excess moisture and pressed into shape to obtain highly hydrolyzed ceramics;

[0071] (6) The high-hydrolysis ceramic is sintered at 600°C for 1 hour, then heated to 950°C and sintered for another 0.5 hours. After that, it is cooled to room temperature in the furnace to obtain the final high-hydrolysis ceramic product.

[0072] like Figure 2 The image shown is a comparison of the 3mm thick highly hydrolyzable ceramic sample before and during hydrolysis in this embodiment. Figure 2 (a) is a highly hydrolyzed ceramic sample before hydrolysis. Figure 2 (b) shows a highly hydrolyzed ceramic sample undergoing hydrolysis. As can be seen from the figure, the highly hydrolyzed ceramic sample was destroyed by hydrolysis in water.

[0073] Example 4

[0074] This embodiment provides a method for preparing highly hydrolyzable ceramics, including the following steps:

[0075] (1) Based on the chemical composition of the high hydrolysis ceramic aB2O3·bSiO2·cAl2O3, weigh the raw materials kaolin (Al2O3·2SiO2·2H2O) and boric acid (H3BO3) according to the ratio of a=50%, b=27%, c=23%.

[0076] (2) Crush the kaolin and ball mill it into a slurry with deionized water in a ball mill; the solid content of the slurry is 25%;

[0077] (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 300℃ for 4 hours to make ceramic pre-fired powder;

[0078] (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; the solid content of the slurry is 25%;

[0079] (5) The slurry is dried to remove excess moisture and pressed into shape to obtain highly hydrolyzed ceramics;

[0080] (6) The high-hydrolysis ceramic is sintered at 500°C for 1 hour, then heated to 850°C and sintered for another hour. After that, it is cooled to room temperature in the furnace to obtain the final high-hydrolysis ceramic product.

[0081] Studies have shown that the thickness hydrolysis rate of low-hydrolysis ceramics is approximately 0.1-1 mm / d, while the thickness hydrolysis rate of high-hydrolysis ceramic cover plates is approximately 4-10 mm / h.

[0082] Example 5

[0083] This embodiment provides a method for preparing a low-hydrolysis ceramic cover plate, including the following steps:

[0084] (1) Based on the chemical composition of low hydrolysis ceramics aB2O3·bSiO2·cAl2O3·dCaO, weigh the raw materials kaolin (Al2O3·2SiO2·2H2O), quicklime (Ca(OH)2) and boric acid (H3BO3) according to the proportion of a=15%, b=40.6%, c=34.4% and d=10%.

[0085] (2) Crush kaolin and quicklime, and then ball mill them into a slurry using deionized water; the solid content of the slurry is 20%;

[0086] (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 400℃ for 3 hours to make ceramic pre-fired powder;

[0087] (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; the solid content of the slurry is 40%;

[0088] (5) The slurry is cast into sheets and pressed into a pre-formed low-hydrolysis ceramic cover plate with a preset structure.

[0089] (6) The pre-formed low-hydrolysis ceramic cover plate is sintered at 600℃ for 1 hour, then heated to 1050℃ for 2 hours, and then cooled to room temperature in the furnace to obtain the final low-hydrolysis ceramic cover plate.

[0090] Example 6

[0091] This embodiment provides a method for preparing a highly hydrolyzable ceramic cover plate, including the following steps:

[0092] (1′) Based on the chemical composition of the high hydrolysis ceramic aB2O3·bSiO2·cAl2O3·dBaO, weigh the raw materials kaolin (Al2O3·2SiO2·2H2O), barium oxide (BaO) and boric acid (H3BO3) according to the proportion of a=30%, b=35%, c=30%, d=5%.

[0093] (2′) Crush kaolin and barium oxide, and ball mill them into a slurry in a ball mill with deionized water; the solid content of the slurry is 20%;

[0094] (3′) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 400℃ for 3 hours to make ceramic pre-fired powder;

[0095] (4′) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; the solid content of the slurry is 40%;

[0096] (5′) The slurry is cast into sheets and pressed into a pre-formed high-hydrolysis ceramic cover plate with a preset structure;

[0097] (6′) The high-hydrolysis ceramic cover plate was sintered at 600℃ for 1 hour, and then heated to 950℃ for 0.5 hours. After that, it was cooled to room temperature in the furnace to obtain the final high-hydrolysis ceramic cover plate.

[0098] Example 7

[0099] This embodiment provides a packaging structure for achieving self-destruction of passive silicon-based devices based on hydrolytic ceramics, such as... Figure 3 As shown, the device includes a housing 1, a base 7, and a self-destruct assembly. The bottom of the housing 1 is fixedly connected to the base 7, forming a first chamber 11 for encapsulating a silicon-based device 2. The top of the housing 1 has a mounting groove 12a for accommodating the self-destruct assembly. The mounting groove 12a is located above the first chamber 11 and is connected to the first chamber 11. The self-destruct assembly includes a low-hydrolysis ceramic cover plate 3, a high-hydrolysis ceramic cover plate A 4a, a high-hydrolysis ceramic cover plate B 4b, a heating agent 5, and a corrosive agent 6.

[0100] The inner side of the mounting groove 12 is provided with stepped grooves from top to bottom for placing low-hydrolysis ceramic cover plate 3, high-hydrolysis ceramic cover plate A 4a, and high-hydrolysis ceramic cover plate B 4b in sequence. The low-hydrolysis ceramic cover plate 3, high-hydrolysis ceramic cover plate A 4a, and high-hydrolysis ceramic cover plate B 4b are fixedly connected to the corresponding stepped grooves by sealant. The top surface of the low-hydrolysis ceramic cover plate 3 is flush with the top surface of the shell 1.

[0101] The low-hydrolysis ceramic cover plate 3 and the high-hydrolysis ceramic cover plate A 4a form a third chamber 122a for containing the exothermic agent 5; the high-hydrolysis ceramic cover plate A 4a and the high-hydrolysis ceramic cover plate B 4b form a second chamber 121a for containing the corrosive agent 6.

[0102] The low-hydrolysis ceramic cover plate 3 was prepared according to the method provided in Example 5. The high-hydrolysis ceramic cover plate A 4a and the high-hydrolysis ceramic cover plate B 4b have the same composition and were both prepared according to the method provided in Example 6.

[0103] The exothermic agent 5 has a block structure and is obtained by pressing CaO. The exothermic agent can accelerate the corrosion rate of silicon-based device 2 by etchant 6, and also accelerate the corrosion rate of high-hydrolysis ceramic cover plate A and high-hydrolysis ceramic cover plate B. Etcher 6 has a block structure and is obtained by pressing KOH; it is used to destroy silicon-based device 2.

[0104] The silicon-based device 2 is fixed to the base 7 by welding using conventional semiconductor processes.

[0105] Example 8

[0106] This embodiment provides a packaging structure for achieving self-destruction of passive silicon-based devices based on hydrolytic ceramics, such as... Figure 4As shown, the device includes a housing 1, a base 7, and a self-destruct assembly. The bottom of the housing 1 is fixedly connected to the base 7, forming a first chamber 11 for encapsulating a silicon-based device 2. The top of the housing 1 has a mounting groove 12b for accommodating the self-destruct assembly. The mounting groove 12b is located above the first chamber 11 and is connected to the first chamber 11. The self-destruct assembly includes a low-hydrolysis ceramic cover plate 3, a high-hydrolysis ceramic cover plate A 4c, a heating agent 5, and an etchant 6.

[0107] The low-hydrolysis ceramic cover plate 3 is fixedly connected to the stepped groove at the top of the mounting groove 12b by sealant, and the top surface of the low-hydrolysis ceramic cover plate 3 is flush with the top surface of the housing 1. A groove is formed at the bottom of the low-hydrolysis ceramic cover plate 3. The outer edge of the high-hydrolysis ceramic cover plate A 4c is fixedly connected to the inner side of the groove of the low-hydrolysis ceramic cover plate by sealant. The high-hydrolysis ceramic cover plate A 4c has an upwardly protruding partition 41; the partition 41 divides the chamber formed by the low-hydrolysis ceramic cover plate 3 and the high-hydrolysis ceramic cover plate A 4c into two independent third chamber 122b, which respectively contains the exothermic agent 5 and the corrosive agent 6.

[0108] The low-hydrolysis ceramic cover plate 3 was prepared according to the method provided in Example 5. The high-hydrolysis ceramic cover plate A 4c was prepared according to the method provided in Example 6.

[0109] The heating agent 5 has a block structure and is obtained by pressing nano-aluminum powder. The heating agent can accelerate the corrosion rate of the silicon-based device 2 by the etchant 6, and can also accelerate the corrosion rate of the highly hydrolyzable ceramic cover plate. The etchant 6 has a block structure and is obtained by pressing KOH, and is used to destroy the silicon-based device 2.

[0110] The silicon-based device 2 is fixed to the base 7 by welding using conventional semiconductor processes.

[0111] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A packaging structure for achieving self-destruction of passive silicon-based devices based on hydrolytic ceramics, characterized in that: Includes the casing, base, and self-destruct components; The bottom of the housing is fixedly connected to the base, and a first chamber for encapsulating silicon-based devices is formed between the two. The top of the housing is provided with a mounting groove for accommodating a self-destruct component. The mounting groove is located above the first chamber and is connected to the first chamber. The self-destruct component includes a low-hydrolysis ceramic cover plate, a high-hydrolysis ceramic cover plate A, and an etchant for destroying silicon-based devices; the low-hydrolysis ceramic cover plate is fixedly connected to the top of the mounting groove; the high-hydrolysis ceramic cover plate A is fixedly connected to the inner side of the mounting groove or the bottom of the low-hydrolysis ceramic cover plate; a second chamber for containing the etchant is formed between the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A; the thickness hydrolysis rate of the low-hydrolysis ceramic cover plate is less than the thickness hydrolysis rate of the high-hydrolysis ceramic cover plate A. The self-destruct component also includes a heating agent; the heating agent and the corrosive agent are placed in a stacked or horizontal manner, as specifically configured as follows: When the exothermic agent and corrosive agent are stacked, the self-destruct component also includes a high-hydrolysis ceramic cover plate B; the high-hydrolysis ceramic cover plate B has the same composition as the high-hydrolysis ceramic cover plate A; the high-hydrolysis ceramic cover plate B is disposed below the high-hydrolysis ceramic cover plate A and is fixedly connected to the inner side of the mounting groove; the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A form a third chamber for containing the exothermic agent; a second chamber for containing the corrosive agent is formed between the high-hydrolysis ceramic cover plate A and the high-hydrolysis ceramic cover plate B; When the exothermic agent and the corrosive agent are placed horizontally, the high-hydrolysis ceramic cover plate A forms an upwardly protruding partition; the partition divides the chamber formed by the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A into two independent third chambers that respectively contain the exothermic agent and a second chamber that contains the corrosive agent.

2. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 1, characterized in that: The thickness hydrolysis rate of the low-hydrolysis ceramic cover plate is less than 1 mm / d, and the thickness hydrolysis rate of the high-hydrolysis ceramic cover plate is 4-10 mm / h.

3. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 2, characterized in that: Both the low-hydrolysis ceramic cover plate and the high-hydrolysis ceramic cover plate A are borosilicate ceramics with the chemical formula aB2O3·bSiO2·cAl2O3·dXO, where a, b, c, and d are mass percentages, a+b+c+d=1; and XO is a metal oxide, where X is Ba, Ca, or Mg. For low-hydrolysis ceramic covers, 10%≤a≤15%, 40%≤b≤50%, 30%≤c≤40%, 5%≤d≤10%; For high-hydrolysis ceramic cover plate A, 30%≤a≤50%, 20%≤b≤35%, 20%≤c≤30%, and 0%≤d≤5%.

4. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 3, characterized in that: The corrosive agent is NaOH or KOH.

5. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 1, characterized in that: When the exothermic agent and corrosive agent are placed in a stacked manner, a stepped groove is provided inside the installation groove for placing the low-hydrolysis ceramic cover plate, the high-hydrolysis ceramic cover plate A, and the high-hydrolysis ceramic cover plate B.

6. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 1, characterized in that: When the heating agent and the corrosive agent are placed horizontally, a groove is provided at the bottom of the low-hydrolysis ceramic cover plate; the outer edge of the high-hydrolysis ceramic cover plate A is fixedly connected to the inner side of the groove of the low-hydrolysis ceramic cover plate by sealant, and the whole is placed on the stepped groove opened inside the installation groove.

7. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 1, characterized in that: The heating agent is CaO or nano-aluminum powder.

8. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 3, characterized in that: The preparation steps of the low-hydrolysis ceramic cover plate are as follows: (1) Weigh the raw materials kaolin, the compound containing X and boric acid according to the chemical composition of the low hydrolysis ceramic cover plate; (2) Crush the kaolin and the compound containing X, and then ball mill them into a slurry using deionized water; (3) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 300-400℃ for 3-6 hours to make ceramic pre-fired powder; (4) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; (5) The slurry is cast into sheets and pressed into a pre-formed low-hydrolysis ceramic cover plate with a preset structure; (6) Sinter the preformed low-hydrolysis ceramic cover plate at 500-600℃ for 1-2 hours, and then heat it to 950-1050℃ for 2-3 hours to obtain the final low-hydrolysis ceramic cover plate.

9. The packaging structure for self-destruction of passive silicon-based devices based on hydrolytic ceramics according to claim 3, characterized in that: The preparation steps of the high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B are as follows: (1′) Weigh the raw materials kaolin, the compound containing X and boric acid according to the chemical composition of the high-hydrolysis ceramic cover plate A or the high-hydrolysis ceramic cover plate B; (2′) Crush the kaolin and the compound containing X, and then ball mill them into a slurry using deionized water; (3′) Dry the slurry, crush it and grind it into powder, and pre-sinter it at 300-400℃ for 3-6 hours to make ceramic pre-fired powder; (4′) Add boric acid and deionized water to the pre-fired ceramic powder and ball mill it into a slurry again; (5′) The slurry is cast into sheets and pressed into a pre-formed high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B. (6′) Sinter the pre-formed high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B at 500-600℃ for 1-2 hours, and then heat it to 850-950℃ and continue sintering for 0.5-1 hours to obtain the final high-hydrolysis ceramic cover plate A or high-hydrolysis ceramic cover plate B.

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