Preparation method of Al / Cu2O / SnO2 / Al energetic PN junction diode
By fabricating an Al/Cu2O/SnO2/Al energetic PN junction diode, the problem that existing self-destructing chip technologies are difficult to adapt to integrated semiconductor and integrated circuit processes is solved, and the chip self-destruction effect of energy release after excitation is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-28
- Publication Date
- 2026-03-10
AI Technical Summary
Existing self-destructing chip technologies are difficult to adapt to the manufacturing processes of integrated semiconductors and integrated circuits, and existing methods suffer from problems such as complex processes, incompleteness, or reliance on micro- and nano-materials.
An Al/Cu2O/SnO2/Al energetic PN junction diode fabrication method was adopted, utilizing magnetron sputtering and photolithography techniques to fabricate an energetic PN junction diode suitable for IC and CMOS technologies. The chip self-destruction was achieved by releasing energy through an aluminothermic reaction.
It achieves normal functionality under normal operating conditions and can release a large amount of energy to complete chip self-destruction under predetermined conditions, making it suitable for integrated semiconductor and integrated circuit manufacturing processes.
Smart Images
Figure CN121645912A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of self-destruction chip, and particularly relates to a preparation method of Al / Cu2O / SnO2 / Al energetic PN junction diode. BACKGROUND
[0002] The role of information is crucial, and information security problems in information acquisition, processing, storage, transmission and use have become one of the major technical problems to be solved. At present, countries focus on the research and development of various types of new functional chips in order to solve the information link technology of information collection, processing, storage, transmission and use, and use software encryption technology to encrypt information to improve the security of information. However, the software encryption method cannot completely eliminate the traces of secret information in the information chip, and is easy to be recovered by the underlying cracking software technology, and the security of information is not thorough.
[0003] The current mainstream self-destruction technology includes transient electronic damage technology, stress damage technology, chemical corrosion technology and energetic material damage technology. Transient electronic technology uses degradable metals, polymers and semiconductors as the main materials of the device. In addition, when triggered by heat, light, solution and other conditions, the material can completely self-destruct and disappear. This technology has high compatibility with the field of flexible electronics, but it is highly dependent on micro-nano material technology, and the transient degree is low. Stress damage technology is to introduce stress into the device structure, and amplify the stress effect under specific adjustment, so as to damage the microstructure of the device and achieve the effect of loss of device function. This technology is safe and compatible with chip manufacturing process, but the difficulty lies in the complex microstructure design and process conditions. Chemical etching technology designs to fill chemical etching agent in the device microcavity structure. By destroying the cavity wall, the chemical solution is released to corrode the chip, thereby destroying the device. Although the principle of this technology is simple, the design and processing process of the liquid storage cavity are complex, and the method of stable storage of chemical etching agent in the cavity. Energetic material destruction refers to adding high-energy materials in the device, which can be destroyed by releasing a large amount of heat energy through chemical reaction. The destruction method is violent, but it is challenging to find a suitable energetic material system while considering the heat release performance and safety.
[0004] However, some of these methods can only be used for specially constructed chips, and they cannot fully adapt to the manufacturing process and technology of integrated semiconductor (CMOS) and integrated circuit (IC). SUMMARY
[0005] The purpose of the present application is to design a preparation method of Al / Cu2O / SnO2 / Al energetic PN junction diode, to prepare Al / Cu2O / SnO2 / Al energetic PN junction diode, to realize the conventional function of the chip, and to release a large amount of energy to complete the self-destruction of the chip after excitation.
[0006] The technical solution for achieving the object of the present application is an energetic PN junction diode applied to a self-destruction chip, which comprises, from bottom to top, Al, SnO2, Cu2O and Al. The Al and Cu2O constitute an energetic region of an aluminum thermite, and the Cu2O and SnO2 constitute a semiconductor material region, i.e. a PN junction.
[0007] The application discloses an Al / Cu2O / SnO2 / Al energetic PN junction diode and a preparation method thereof. Step (1): the processed wafer is placed on a spin coater, the rotation speed and time of the spin coater are adjusted, photoresist is coated, and the wafer after spin coating is placed in an oven for pre-baking to remove the solvent in the photoresist; Step (2): the wafer obtained in step (1) is placed in a photoetching machine for pre-exposure, and the wafer after exposure is placed in an oven for reverse baking; Step (3): the wafer obtained in step (2) is placed in a photoetching machine for flood exposure; Step (4): a developing solution is prepared, the wafer obtained in step (3) is placed in the developing solution for development, and pattern drawing is completed; Step (5): the wafer obtained in step (4) is placed in an oven to stabilize the photoresist on the wafer surface, and photoetching is completed; Step (6): the wafer obtained in step (5) is subjected to magnetron sputtering to prepare lower metal Al; Step (7): the wafer obtained in step (6) is subjected to stripping treatment to remove the excess photoresist and sputtering material, and a wafer with successfully prepared lower metal Al is obtained; Step (8): steps (1) to (7) are repeated to sequentially prepare semiconductor SnO2, semiconductor Cu2O and upper metal Al, and an Al / Cu2O / SnO2 / Al energetic PN junction diode is obtained.
[0008] Further, In step (1), the thickness of the wafer is 425-475 µm, the photoresist to be coated is 6-8 mL, the rotation speed of the spin coater is 500-2500 rpm, the time is 10-20 s, the pre-baking temperature is 100°C, and the time is 120 s; In step (2), the pre-exposure energy is 30 mJ, the reverse baking temperature is 115°C, and the time is 150 s; In step (3), the flood exposure energy is 250 mJ; In step (4), the developing solution is prepared in a ratio of developing solution: deionized water = 1:5-1:10 (volume ratio), and the developing time is 40 s-150 s; In step (5), the drying temperature is 100-120°C, and the drying time is 1-2 min; In step (7), the solvent used for stripping is acetone or ethanol.
[0009] Compared with the prior art, the significant advantages of this invention are: This method for fabricating energetic diodes employs magnetron sputtering and photolithography techniques and is applicable to both IC and CMOS technologies.
[0010] The Al / Cu2O / SnO2 / Al energetic PN junction diode prepared by this method has both logic and energy properties. The diode has a turn-on voltage of 1.69V and a cut-off voltage of -2V. Al and Cu2O form an aluminothermic agent to achieve exothermic reaction. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of an Al / Cu2O / SnO2 / Al energetic PN junction diode.
[0012] Figure 2 This is a flowchart illustrating the fabrication process of an Al / Cu2O / SnO2 / Al energetic PN junction diode.
[0013] Figure 3 This is the XPS spectrum of a Cu2O monolayer thin film.
[0014] Figure 4 XPS spectrum of SnO2 monolayer thin film.
[0015] Figure 5 SEM image of the cross-section of an Al / Cu2O / / SnO2Al energetic PN junction diode.
[0016] Figure 6 The UV-Vis absorption spectra are for Al / SnO2 / Cu2O, SnO2, and Cu2O.
[0017] Figure 7 The band gap diagrams are for Al / SnO2 / Cu2O, SnO2, and Cu2O.
[0018] Figure 8 Current-voltage characteristics of Al / Cu2O / SnO2 / Al energetic PN junction diodes were tested.
[0019] Figure 9 The image shows the DSC test curves for Al / Cu2O.
[0020] Figure 10 The graph shows the TG test curves for Al / Cu2O. Detailed Implementation
[0021] The present invention will now be described in further detail with reference to the accompanying drawings.
[0022] like Figure 1As shown, an Al / Cu2O / SnO2 / Al energetic PN junction diode comprises, from bottom to top, metallic material Al, semiconductor material SnO2, semiconductor material Cu2O, and metallic material Al again. The aluminothermic system composed of semiconductor material Cu2O and metallic material Al forms the energetic region, while the PN structure formed by semiconductor materials SnO2 and Cu2O forms the semiconductor region. Under predetermined conditions and with a certain stimulus, the Al / Cu2O / SnO2 / Al energetic diode can be excited, converting electrical energy into heat energy, thereby stimulating the aluminothermic reaction of the aluminothermic agent, releasing a large amount of energy, and achieving the destruction of a single junction, thus achieving the purpose of chip damage.
[0023] like Figure 2 As shown, four thin films, Al, SnO2, Cu2O, and Al, are sequentially deposited on a wafer, including the following steps: Step 1: Place the processed wafer on a spin coater, adjust the spin coater speed and time, coat with photoresist and spin coat, then place the spin-coated wafer in an oven for pre-baking to remove the solvent from the photoresist. Step 2: Place the wafer obtained in step (1) into a photolithography machine for pre-exposure, and then place the exposed wafer into an oven for reverse baking; Step 3: Place the wafer obtained in step (2) into a photolithography machine for generalized exposure; Step 4: Prepare the developing solution, place the wafer obtained in step (3) in the developing solution to develop, and complete the patterning; Step 5: Place the wafer obtained in step (4) in an oven to stabilize the photoresist morphology on the wafer surface and complete the photolithography. Step 6: Prepare the lower metal Al layer using magnetron sputtering on the wafer obtained in step (5); Step 7: The wafer obtained in step (6) is stripped to remove excess photoresist and sputtering material, and a wafer with the lower metal Al layer successfully fabricated is obtained. Step 8: Repeat steps (1) to (7) to prepare semiconductor SnO2, semiconductor Cu2O, and upper metal Al in sequence to obtain an Al / Cu2O / SnO2 / Al energetic PN junction diode.
[0024] The present invention provides a specific implementation method. In step one, the thickness of the wafer is 425~475µm, the amount of photoresist coated is 6~8mL, the spin coater speed is 500~2500rpm, the time is 10~20s, the pre-baking temperature is 100℃, and the time is 120s. The present invention provides a specific implementation method in which, in step two, the pre-exposure energy is 30mJ, the reverse baking temperature is 115℃, and the time is 150s; This invention provides a specific implementation method in which, in step three, the overexposure energy is 250 mJ; This invention provides a specific implementation method in which, in step four, the developer solution ratio is 1:5 to 1:10 (volume ratio) and the development time is 40s to 150s. In a specific embodiment of the present invention, in step five, the drying temperature is 100~120℃ and the drying time is 1~2 min; The present invention provides a specific embodiment in which the solvent used for stripping in step seven is acetone or ethanol.
[0025] like Figure 3 As shown in Figure 4, Cu 2p3 / 2 has a kinetic energy of 932.38 eV and Cu 2p1 / 2 has a kinetic energy of 952.28 eV. The kinetic energy obtained from the Auger spectrum is 915.92 eV. Auger parameter: Cu 2p3 / 2 + Cu LMM kinetic energy: 932.38 + 915.92 = 1848.3. Cu 2p3 / 2 is located at 932.38 eV, O1s is located at 530.38 eV, Auger parameter 1848.3 eV, indicating that the sputtered Cu2O target yields Cu2O. Sn 3d3 / 2 has a kinetic energy of 487.18 eV and Sn 3d5 / 2 has a kinetic energy of 495.58 eV. 495.58 - 487.18 = 8.4, indicating that the sputtered SnO2 target yields SnO2.
[0026] like Figure 5 As shown, the prepared Al / Cu2O / SnO2 / Al energetic PN junction diode structure is as follows: bottom layer Al 325nm, SnO2 365nm, Cu2O 190nm, and top layer Al 170nm.
[0027] like Figure 6 Figure 7 shows the sample bandgap diagrams obtained from the UV absorption spectrum and the UV-Vis absorption spectrum processed using the Tauc plot method. The bandgap of Cu2O is 1.93 eV, the bandgap of SnO2 is 3.37 eV, and the bandgap of the Al / SnO2 / Cu2O film is 2.78 eV.
[0028] like Figure 8 As shown, the test results of the Al / Cu2O / SnO2 / Al energetic PN junction diode show that the turn-on voltage is 1.5V and the reverse leakage current is about 10E-9A, indicating good current-cutting effect.
[0029] like Figure 9As shown, the DSC test conditions were as follows: heating from 100℃ to 800℃ at a rate of 10℃ / min under air conditions. The DSC curves show an endothermic peak at 246℃ (enthalpy 192.3 J / g) and a strong exothermic peak at 483℃ (enthalpy 2401.2 J / g). The sample exhibits significant exothermic behavior. The strong exothermic peak at 483℃ is the core evidence, with an enthalpy of 2401.2 J / g, suggesting that this exothermic process is mainly dominated by the aluminothermic reaction. The significant intensity and high enthalpy of this exothermic peak reflect a vigorous reaction and high exothermic efficiency, indicating that the Al / Cu2O film possesses typical aluminothermic reactivity and exhibits a clear strong exothermic characteristic during heating.
[0030] like Figure 10 As shown, the TG test conditions were a heating rate of 10℃ to 800℃ at 10℃ / min under air conditions. The TG curve shows a peak at 172℃, corresponding to the maximum weight loss rate, which is related to the weight loss range of 136-555℃ and is attributed to the dehydration reaction of adsorbed water and hydroxides. Regarding mass changes, a 4.1% weight gain occurred between 100-136℃, presumably due to Al surface oxidation; a 3.6% weight loss occurred between 136-555℃, presumably due to hydroxide dehydration; a 0.2% weight gain occurred between 555-638℃, presumably due to Cu surface oxidation or residual oxidation; and a 1.5% weight loss occurred between 638-800℃, possibly due to the decomposition of trace impurities.
[0031] This invention provides a method for fabricating an Al / Cu2O / SnO2 / Al energetic diode. On one hand, under normal operating conditions, the Al / Cu2O / SnO2 / Al energetic diode can perform conventional diode functions; on the other hand, under predetermined conditions, it can release energy to achieve chip self-destruction. The energetic PN junction diode consists of a four-layer structure, including an energetic region and a semiconductor region. Its simple structure is suitable for integrated semiconductor and integrated manufacturing technologies.
Claims
1. A method for preparing an Al / Cu2O / SnO2 / Al energetic PN junction diode, characterized in that, The method comprises: sequentially placing the wafer into deionized water, acetone and ethanol for ultrasonic treatment, taking out and drying, and sequentially depositing Al, SnO2, Cu2O and Al four-layer films on the wafer by using photolithography and magnetron sputtering to obtain an Al / Cu2O / SnO2 / Al energetic PN junction diode.
2. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 1, characterized in that, The ultrasonic time is 5 minutes.
3. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 1, characterized in that, The drying temperature is 100 DEG C, and the drying time is 6 minutes.
4. A method for preparing an Al / Cu2O / SnO2 / Al energetic PN junction diode, characterized in that, It comprises: Step (1): placing the treated wafer on a spin coater, adjusting the rotation speed and time of the spin coater, coating photoresist, and spin coating, and then placing the spin-coated wafer in an oven for pre-baking to remove the solvent in the photoresist; Step (2): placing the wafer obtained in step (1) in a photoetching machine for pre-exposure, and then placing the exposed wafer in an oven for reverse baking; Step (3): placing the wafer obtained in step (2) in a photoetching machine for flood exposure; Step (4): preparing a developing solution, and developing the wafer obtained in step (3) in the developing solution to complete pattern drawing; Step (5): placing the wafer obtained in step (4) in an oven to stabilize the photoresist on the wafer surface, and completing photoetching; Step (6): preparing the lower metal Al on the wafer obtained in step (5) by magnetron sputtering; Step (7): stripping the wafer obtained in step (6) to remove excess photoresist and sputtering material, and obtaining the wafer with successfully prepared lower metal Al; Step (8): repeating steps (1) to (7) to sequentially prepare the semiconductor SnO2, the semiconductor Cu2O and the upper metal Al, and obtaining the Al / Cu2O / SnO2 / Al energetic PN junction diode.
5. The preparation method of the Al / Cu2O / SnO2 / Al energetic PN junction diode according to claim 4, wherein In step (1), the thickness of the wafer is 425-475 µm, the photoresist coating is 6-8 mL, the rotation speed of the spin coater is 500-2500 rpm, the time is 10-20 s, the pre-baking temperature is 100 DEG C, and the time is 120 s.
6. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 4, characterized in that, In step (2), the pre-exposure energy is 30 mJ, the reverse baking temperature is 115 DEG C, and the time is 150 s.
7. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 4, characterized in that, In step (3), the flood exposure energy is 250 mJ.
8. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 4, characterized in that, In step (4), the developing solution is prepared in a volume ratio of developing solution: deionized water = 1:5-1:10, and the developing time is 40-150 s.
9. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 4, characterized in that, In step (5), the drying temperature is 100-120 DEG C, and the drying time is 1-2 minutes.
10. The method for fabricating an Al / Cu2O / SnO2 / Al energetic PN junction diode as described in claim 4, characterized in that, In step (7), the solvent used for stripping is acetone or ethanol.