Since hafnium-oxide-based ferroelectric tunnel junctions are compatible with the standard CMOS process，they have great application potential in the field of random access memory. The tunneling electroresistance effect in TiN/HZO/Pt ferroelectric tunnel junctions was rigorously analyzed using the Airy function. The theoretical results indicate that: when the bias voltage is high，the tunneling conductance and Tunneling Electroresistance Ratio（TER）will oscillate with both the bias voltage and the thickness of tunneling layer. Physically，the oscillations originate from the interference between the incident and reflected electron waves in the tunneling layer. The theoretical analysis indicates the physical mechanism underlying the experiments in hafnium oxide-based ferroelectric tunnel junctions. In addition，when the bias voltage is applied to the Pt electrode，there exists negative TER. This phenomenon indicates that the tunneling conductance is not only related to the average height of the barrier，but also associated with the potential structure of the tunneling layer. The present work provides a theoretical method for calculating the tunneling electroresistance effect in hafnium oxide-based ferroelectric tunnel junctions，and lays a theoretical foundation for the applications of hafnium oxide-based ferroelectric tunnel junctions in the field of random access memory.

To address the temperature gradient requirements for low-temperature soldering and high-temperature service，variable-temperature solders were developed，and the regulatory effects of Ni particle content on their properties and those of brazed joints were clarified. Using 4#SAC305solder powder as the base material，2-5 μm Ni particles and HP01high-activity flux were compounded to prepare Ni-based variable temperature solder paste. The effects of Ni content on the melting characteristics and wettability of the solder paste，as well as the growth of intermetallic compounds（IMCs）at the brazed joint interface and changes in shear strength during aging，were investigated. The results show that when the Ni content is 10%，the solder's melting point can rise to 227 ℃，with only a marginal increase observed after high-temperature storage. Wettability initially enhanced and subsequently decreased as the Ni content increased，resulting in a 60% reduction in the spread area observed at 20% Ni. The growth of the interfacial IMC layer corresponds well with the square root of the aging duration，achieving a thickness of 37.611 μm after 360hours of aging at 20% Ni. Under the same Ni content，shear strength decreases with prolonged aging，and under the same aging condition，it decreases with increasing Ni content. The solder paste with 10% Ni exhibitsminimal impact on shear strength due to aging，and its fracture surface displays a mixed ductile-brittle characteristic. The variable-temperature solder with 10% Ni content demonstrates the best overall performance，effectively raises the solder's melting point while exhibiting excellent stability during high-temperature service，thereby meeting the requirements for temperature gradient applications.

Low Temperature Co-fired Ceramics（LTCC）technology is recognized as one of the most promising three-dimensional packaging technologies. As the pastes used in LTCC technology evolve from gold to silver and copper，electroless Ni/Pd/Au（ENEPIG）plating has become a crucial step to prevent post-sintering oxidation or electromigration failures of embedded circuits. Based on this context，this study comprehensively reviews the corrosion mechanisms of LTCC substrates in acidic/alkaline environments. Typical corrosion behaviors and failure cases are analyzed to reveal their common degradation patterns. The intrinsic relationships among the composition，structure，and corrosion resistance of LTCC sintering additive glasses under diverse corrosive conditions are systematically summarized. Furthermore，design principles for sintering additive glasses applicable to electroless-plated LTCC substrates are discussed，providing theoretical guidance for developing low-cost and high-reliability LTCC materials.

In recent years，tungsten oxide（WO₃）nanomaterials have garnered significant attention in the field of gas sensors. However，their practical applications are limited by drawbacks such as high operating temperatures and low sensitivity. A series of MoS₂/WO₃ nanocomposites were synthesized via a hydrothermal method. Gas-sensing tests for nitrogen dioxide（NO₂）demonstrated that these composites exhibit excellent sensing performance over a working temperature range of 20-180℃ and an NO₂ concentration range of 1ppm-100ppm. Notably，the MoS₂/WO₃ composite with a 2% MoS₂ doping ratio achieved a remarkable response value of 1123.19 toward 20ppm NO₂ at 140℃—seven times that of pure WO₃ at its optimal working temperature（80℃）. Characterization and mechanistic studies revealed that the combination of MoS₂ and WO₃ forms a p-n heterojunction，inducing a charge depletion layer at the interface. Additionally，the band bending effect reduces the energy barrier for gasmolecule adsorption，thereby enhancing both the gas adsorption capacity and surface reaction activity of the composite. This study provides a novel material design strategy and technical approach for developing high-performance，low-temperature NO₂ gas sensors.

The limited energy density of supercapacitors poses significant constraints on their practical applications. To address this issue，in this study，the hydrothermal method was used to grow an anthracene-based covalent organic framework（DaTp-COF）in-situ on the surface of graphene oxide（GO），and a novel DaTp/rGO composite electrode material was prepared. The structure，morphology，and electrochemical properties of the material were systematically characterized. The results reveal that the DaTp/rGO composite possesses a unique hierarchical porous structure with micropores，mesopores，and macropores. Meanwhile，the electron-withdrawing effect of the anthracene groups in the structure induces apseudocapacitive response of the Schiff base groups. Benefiting from this，in a three-electrode system with a 0.5mol·L^-1 sulfuric acid electrolyte，the specific capacitance of DaTp/rGO electrode reaches 251F·g^-1 at a current density of 1A·g^-1，which is significantly higher than that of rGO electrode material. In the ionic liquid electrolyte system，the DaTp/rGO electrode only exhibits the characteristics of electric double layer capacitance. However，owing to its excellent hierarchical pore structure，the electrode's specific capacitance is still as high as 158F·g^-1 at a current density of 1A·g^-1，and the capacitance retention rate is 78.82% after 10000 cycles. This study used the in-situ growth method to achieve the synergy between DaTp-COF and rGO，providing new ideas for the research and development of high-performance supercapacitor electrode materials，and helping supercapacitors break through their application limitations.

To address overheating risks in 3D stacked packaged chips caused by increased power consumption，a thermal resistance matrix-based method was proposed for junction temperature prediction，thereby supporting thermal design and management. A DDR3stacked chip was selected as the case study. Instead of relying on traditional experimental measurements，simulation modeling was utilized to obtain thermal characteristic parameters. Through structural analysis of the 3D configuration，a simulation model was developed using Icepak software. A JESD51-2-compliant thermal test environment was designed to characterize the thermal resistance matrix. Junction temperatures of each chip layer under varying conditions were predicted，and the results demonstrate prediction errors of less than 1% compared to simulation results. This method enables efficient thermal characterization and provides valuable insights for thermal management of 3D stacked chips.

To meet the high demands of 500-kW electromagnetic propulsion systems on pulse power supplies in terms of energy density，conversion efficiency，and output stability，this paper presented a pulse power supply design based on a hybrid energy storage system combining supercapacitors and film capacitors. The power supply employed supercapacitor banks for energy storage and film capacitor banks for instantaneous high-power discharge. An efficient discharge topology ensured stable power transmission to the load module，while a three-level protection mechanism enhanced the safety and reliability of the discharge process. Experimental results indicate that the prototype achieves an energy density of 18.3Wh/kg，and a conversion efficiency of 91.74%. The pulse current overshoot is controlled within 5.00%. All these metrics satisfy the technical requirements of 500-kW class electromagnetic propulsion systems. The proposed pulse power supply effectively addresses issues such as low energy density，poor conversion efficiency，and insufficient load adaptability in existing medium-power electromagnetic propulsion pulse power supplies.

To address the limitations of conventional opamp-free bandgap reference architectures—specifically their high temperature coefficient and insufficient power supply rejection ratio（PSRR）performance，which fail to meet high-precision application requirements—a high-PSRR bandgap reference circuit with segmented curvature compensation was designed. The proposed bandgap reference circuit adopts a voltage self-regulation structure，which suppresses power supply ripple in the low-frequency range through a negative feedback loop and enhances the anti-interference capability of the output voltage. Furthermore，a PTAT²（proportional to absolute temperature squared）compensation circuit was integrated to generate a compensation current，enabling segmented curvature compensation and thus realizing a significant reduction in the temperature coefficient. The proposed bandgap reference circuit was designed based on the SMIC 0.18 μm CMOS process. Simulation results indicate that，at an operating voltage of 3.3V，the bandgap reference output voltage is 1.197V；over the temperature range of-45 ℃ to 125 ℃，the temperature coefficient is 5.38×10^-6/℃. The PSRR of this bandgap reference at low frequencies reaches-103dB，and the circuit has a quiescent current of 14.8 μA.

Three-dimensional inductors，owing to their small footprint，low loss，and high inductance，are widely applied in MEMS sensors，RF MEMS，and energy storage systems. Traditional three-dimensional MEMS inductors rely on high aspect ratio pillars for support and are typically fabricated by UV-LIGA lithography or through-silicon-via（TSV）technology，resulting in a complex process. To simplify the fabrication，this paper presented a MEMS-based method for three-dimensional arch inductor supported by a non-photosensitive polyimide layer. The inductor employed a high-permeability，Co-based amorphous alloy wire as the magnetic core，significantly enhancing its electrical performance. By optimizing development time to improve the smoothness of polyimide sidewalls，an arch coil was fabricated without high aspect ratio pillars，thus simplifying the process and enhancing device stability. The fabricated MEMS arch inductor achieves an inductance of 1881nH at 78.5MHz，with its electrical performance variation within 3% over the temperature range from 20℃ to 120 ℃.

Biaxially oriented polypropylene（BOPP）exhibits superior energy conversion efficiency and remarkable power density. However，its inherently low dielectric constant fundamentally limits its energy storage capacity，thereby impeding its applications in power storage systems，smart manufacturing，and aerospace engineering. In this study，oxygen plasma treatment was systematically employed to modify the surface of BOPP films，which effectively increased the number of oxygen-containing functional groups on the film surface and enhanced its hydrophilicity. Subsequently，the electrical properties of the modified BOPP films were comprehensively characterized，and the influence of plasma treatment time on these properties was quantitatively investigated. The results indicate that with the extension of plasma treatment time，the dielectric constant of BOPP films increased monotonically from 2.20 to 2.37.When the treatment time was 5min，the breakdown strength and discharge energy density of the modified films reached 785.7MV·m^-1 and 6.78J·cm^-3，respectively. This work provides a feasible and novel strategy for the development of dielectric films with high energy storage performance，laying a foundation for their broader application in the advanced energy storage scenarios.