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Radio frequency (RF) systems utilizing through-silicon vias (TSVs) have been widely used in the aerospace and nuclear industry, which means that studying the total ionizing dose (TID) effect on TSV structures has become necessary. To investigate the TID effect on TSV structures, a 1D TSV capacitance model was established in COMSOL Multiphysics (COMSOL), and the impact of irradiation was simulated. Then, three types of TSV components were designed, and an irradiation experiment based on them was conducted, to validate the simulation results. After irradiation, the S21 degraded for 0.2 dB, 0.6 dB, and 0.8 dB, at the irradiation dose of 30 krad (Si), 90 krad (Si), 150 krad (Si), respectively. The variation trend was consistent with the simulation in the high-frequency structure simulator (HFSS), and the effect of irradiation on the TSV component was nonlinear. With the increase in the irradiation dose, the S21 of TSV components deteriorated, while the variation of S21 decreased. The simulation and irradiation experiment validated a relatively accurate method for assessing the RF systems' performance under an irradiation environment, and the TID effect on structures similar to TSVs in RF systems, such as through-silicon capacitors. [ABSTRACT FROM AUTHOR]

A new frequency-independent modified T-equivalent circuit for 3-D spiral inductor is proposed in this letter. Closed-form analytical expressions are proposed account for configuration and physics-based effect. Compared with double- $\pi $ model, it uses less number of elements to capture the self-resonant frequency (SRF) information. Compared with the existing T-model, it can accurately reflect the characteristics that effect series resistance (ESR) increases of frequency at first and decreases at higher frequency. Verification with measurement data based on through glass vias (TGVs) process up to 20 GHz demonstrates excellent performance prediction. [ABSTRACT FROM AUTHOR]

By using integrated lumped elements based on through-silicon via (TSV) technology, a 3-D low-pass filter (LPF) with ultracompact size and ultrawide stopband is proposed. The 3-D magnetic coupling is enhanced between microsize spiral inductors to increase the mutual inductance and improve the high-frequency performance. A coaxial TSV with enhanced capacitance in high resistivity silicon (HRS) is utilized both as capacitor and as a vertical interconnection without any overhead in area and routing. The 3-D nature of the proposed filter yields a miniaturized size of $0.2\times0.10$ mm2. The LPF is analyzed with equivalent circuit model and validated with the well-matched $S$ -parameters obtained by finite element method simulation and measurement. With −3-dB cutoff frequency at 2.6 GHz, the LPF exhibits an insertion loss below 1 dB, a reflection loss over 17 dB in the passband, and a suppression level over 20 dB from 5.28 up to 40 GHz in the stopband. [ABSTRACT FROM AUTHOR]

Based on spatial power combining technique using a novel waveguide‐to‐microstrip transition, this article proposes a wideband compact double‐layer two‐level power amplifier composed by six commercial power amplifier chips for millimeter‐wave applications. Double antipodal fin line transition and second‐order Wilkinson power divider/combiner are developed for the spatial power combining circuit. Furthermore, the proposed power amplifier is fabricated with over‐mode waveguides. When the input power is 10 dBm, the measured output power reaches up to 23 dBm, and reveals a very small output power variation about 1.4 dB over a bandwidth of 43% from 36 to 56 GHz. Therefore, the proposed power amplifier can be widely used in millimeter‐wave transceiver modules as well as THz sources, due to its excellent wideband performance. [ABSTRACT FROM AUTHOR]

A balanced substrate-integrated waveguide (SIW) bandpass filter (BPF) is designed and fabricated based on through-quartz-via (TQV) technologies in this article. Sixth-order filtering response centered at 41.4 GHz with equal source and load termination is achieved by the transformation of the Chebyshev polynomial. By exploiting cross-coupled resonators, the 3-dB fractional bandwidth (FBW) achieves 12.1%, and the out-of-band rejection is better than 30 dB with frequencies up to $2f_{0}$. High CM suppression can be achieved up to $2.2f_{0}$ with the help of two slots on the bottom metal layer. Based on the theory of the proposed SIW BPF, asymmetric diplexer with different resonance orders for two channels is studied with high isolation and wide stopband. The mixed dual-mode (TE101 and TE301) and single-mode (TE101) junction resonators provide a transition between the input port and two channels. Diplexer with lower and upper channels centered at 20.2 and 37.5 GHz, respectively, is fabricated and measured to verify the proposed structure, which exhibits high isolation better than 40 dB over the whole band and a wide stopband up to $3f_{0}$ of the lower channel. Measured results are in good agreement with the simulations. [ABSTRACT FROM AUTHOR]

A bandwidth optimization model for a novel equivalent 90° transmission-line section is proposed in this paper. Furthermore, the structure of 3-D compact 3-dB branch-line directional coupler and its equivalent-circuit model are presented. They can achieve both excellent isolations between each branch and high-density integration by using equivalent 90° transmission-line sections and coaxial through-silicon via technology in 3-D integrated circuits. Finally, a 3-D coupler is designed with the center frequency of 100 GHz, as well as the bandwidth and size reach 20 GHz and $174\times 236.9\times 208.7\,\,\mu \text{m}^{3}$ , respectively. The results of the 3-D full-wave field solver High-Frequency Structure Simulator and the proposed model are well matched, showing that the proposed model can be used to quickly evaluate the electrical performance of the 3-D coupler before manufacture, thus effectively promoting the design efficiency and quality. [ABSTRACT FROM AUTHOR]

This paper presents a novel 3-D capacitive interconnection technology for a 3-D microsystem, which is called through-silicon capacitor (TSC). Two vias similar to through-silicon via (TSV) are bonded vertically by one oxide bonding layer to form the capacitive coupling. Without the adoption of the backside via revealing process, the complicated back-thinning process for TSC will be reduced further, resulting in the lower cost and lower yield loss for 3-D microsystem. Finite-element analysis indicates that under the same dimensions, TSC has much stronger capacitive coupling effect than conventional capacitive coupling interconnect does. Then, SPICE simulation is carried out and demonstrates that a TSC channel with the radius of $2.5~\mu \text{m}$ , the height of 30- $\mu \text{m}$ via, and the thickness of 1- $\mu \text{m}$ bonding layer can achieve 4-Gb/s data rate and consumes only 0.08 mW/(Gb/s). Moreover, the high-frequency analysis shows that the far-end crosstalk induced by TSC is superior to that induced by TSV. Finally, the potential applications, features, advantages, and disadvantages of TSC, TSV, and capacitive coupling interconnection (CCI) technologies are compared. [ABSTRACT FROM AUTHOR]

The shielded-pair through-silicon vias (SPTSVs) proposed in this paper feature superior transmission properties and high jamming immunity suitable for differential-mode and common-mode transmissions. Based on the recursive approximation algorithm, a novel and efficient method for characterizing the electromagnetic-temperature distribution in dielectrics is proposed for SPTSVs. In addition, considering the proximity effects and eddy current effect in substrate, the ultrabroadband parasitic admittance and electrical coupling models are derived based on 2-D time-varying field and transient polarization mechanism. The collaborative finite-element analysis shows that the proposed model highly agrees with the 3-D full-wave simulation (HFSS 14.0 and Maxwell v16) and the analytical calculation. Then, the dielectric relaxation properties for substrate and oxide are deeply characterized with different design parameters. Finally, the impacts of the substrate effect on electrical characteristics of SPTSVs are revealed. [ABSTRACT FROM AUTHOR]

This paper proposes a substrate integrated waveguide bandpass filter (SIW BPF), exploiting the through-dielectric via (TDV)-based 3-D integrated circuit (3-D IC) technology. The SIW BPF is designed on the dielectric cavity that is etched on the traditional low-resistivity silicon (LRSi) in a 3-D IC system, acting as the insulating material between through-silicon via plugs and LRSi. This construction can reduce prominent eddy current losses in LRSi and coupling losses among TDV plugs for the millimeter-wave application. Benzocyclobutene and glass are chosen as the dielectric cavity due to the low dielectric constant and loss tangent. The detailed design procedure beginning from the normalized Chebyshev low-pass filter to the final optimized SIW BPF is presented. The filter having a 12.5% fractional bandwidth is centered at 159.67 GHz. The return losses and insertion loss across the passband are about −10 and −1.5 dB, respectively. Numerical analysis of the advanced design system and full-wave simulation results of Ansoft’s HFSS show a good agreement. [ABSTRACT FROM AUTHOR]

In this paper, an ultra-compact low-pass filter (LPF) with wide stopband is proposed based on lumped L-C structure in through-silicon via-based 3-D stacked configuration. The spiral inductor (L), interdigital capacitor (C), and the proposed LPF are theoretically analyzed based on parasitic parameters and equivalent circuit models. To evaluate the characteristics, the proposed LPF is simulated by HFSS, fabricated with CMOS-process-compatible technology, and measured with de-embedding method. Simulation and measured results are in good agreement. Compared with the other literature, the proposed LPF has the most compact size of $0.028\lambda _{g }\times 0.017 \lambda _{g}$. ($\lambda _{g}$ is the guide wavelength at $f_{c}$.) With the cutoff frequency at 10.05 GHz, the filter has an insertion loss of 0.14 dB and reflection loss over 13 dB from dc to 9 GHz in the passband. The suppression levels are better than 20 dB from 20.4 up to 40 GHz in the stopband. [ABSTRACT FROM AUTHOR]

A wideband equivalent-circuit model of coaxial-annular through-silicon vias (TSVs) for three-dimensional (3-D) integrated circuits is proposed in this paper. Rigorous closed-form formulas for the resistance and inductance of coaxial-annular TSVs are derived by computing the longitudinal electrical field in Cu and the longitudinal magnetic vector potentials in ${\rm{SiO}}_{2}$ and Si substrate with Bessel functions. The equivalent-circuit model can appropriately capture the skin effect in Cu as well as eddy-current effect in Si substrate. The proposed model is verified using 3-D full-wave field solver high frequency simulator structure, showing that it can yields highly accurate results up to 100 GHz. [ABSTRACT FROM AUTHOR]

The 3-D multistrata integration puts forward high requirements for signal integrity. The shielded-pair through-silicon vias (SPTSVs) proposed in this paper feature superior transmission properties and high jamming immunity suitable for differential-mode and common-mode transmission. Based on the quasi-static field theory, a wideband impedance model of SPTSVs considering the proximity effect, the line-to-line crosstalk, and the eddy current effect is derived. The parasitic parameters calculated by the impedance model are further given. The finite-element analysis shows that the proposed model highly agrees with the 3-D full-wave simulation and the analytical calculation. In addition, the characteristics of the impedance and the transmission coefficient are deeply analyzed with different design parameters. Finally, the impacts of the substrate effect and the metal–oxide–semiconductor effect on electrical characteristics of SPTSVs are revealed. [ABSTRACT FROM PUBLISHER]

Closed-form expressions for the optimized number and size of repeaters in multi-walled carbon nanotube (MWCNT) interconnects are presented. The contact resistance and inductive effects are taken into account. It is found that the propagation delay of MWCNT interconnects can be reduced effectively by inserting repeaters. However, the contact resistance has a significant influence on the optimized number and size of repeaters. Moreover, it is found that both the optimal number of repeaters and the minimum propagation delay are kept almost unchanged with the variation of carbon nanotube (CNT) kinetic inductance. The optimal number of repeaters in the MWCNT interconnect is much smaller than that in its Cu counterpart, thus saving chip area and power consumption. [ABSTRACT FROM AUTHOR]

A novel $\pi $ -type equivalent-circuit model of through-silicon vias (TSVs) for 3-D integrated circuits (3-D ICs) considering eddy current and proximity effects is proposed in this paper. The numerical models for the serial resistance and inductance of TSVs are derived by computing the longitudinal electrical field in Cu and the longitudinal magnetic vector potentials in SiO2 and Si substrate with Fourier-Bessel series. Furthermore, the closed-form formulas for the parallel capacitance and conductance of TSVs are derived by using the conformal mapping method. The proposed $\pi $ -type equivalent-circuit model is verified using 3-D full-wave field solver High-Frequency Structural Simulator, showing that it is highly accurate up to 100 GHz. Using the proposed model, the electrical performance of TSVs with high density can be evaluated accurately and quickly in a wideband frequency range. [ABSTRACT FROM PUBLISHER]

An equivalent-circuit model of Cu-carbon nanotube heterogeneous coaxial through-silicon vias (HCTSVs) in 3-D integrated circuits (3-D ICs) is proposed in this paper. Based on the complex effective conductivity method, the resistances and inductances of Cu-single walled carbon nanotube (SWCNT) HCTSVs and Cu-multi walled carbon nanotube (MWCNT) HCTSVs are compared with that of Cu coaxial through-silicon vias (CTSVs). Furthermore, using the proposed model, the magnitudes of their insertion losses are compared. It is shown that the transmission performance of Cu-SWCNT HCTSVs with higher metallic fraction and Cu-MWCNT HCTSVs is better than that of Cu CTSVs, and the improvement of Cu-MWCNT HCTSVs is more obvious at high frequencies. Finally, the transmission characteristics of Cu-MWCNT HCTSVs are analyzed deeply to provide helpful design guidelines for them in future high-speed 3-D ICs. [ABSTRACT FROM PUBLISHER]

A GNC micro-system which is developed by 3D heterogeneous integration is presented in this paper. The SRAM, SoC, and FPGA chips are integrated onto a silicon interposer. Other chips are mounted on different MCM substrates. The whole 3D GNC micro-system is packaged using POP technology. The volume is reduced from 120 × 120 × 80 mm3 to 40 × 40 × 23 mm3, and the weight is reduced from 1.5 kg to 300 g. The stability of the three axis gyroscopes in the GNC micro-system is 3.11° h−1, 3.25° h−1 and 4.26° h−1, and the accuracy is <5° h−1. The positioning output stability of the satellite navigation receiver is better than 1 m under static conditions. [ABSTRACT FROM AUTHOR]

An equivalent-circuit model of shield differential through-silicon vias (SDTSVs) in 3-D integrated circuits (3-D ICs) is proposed in this paper. The proposed model is verified using the 3-D full-wave field solver High Frequency Simulator Structure, showing that it is highly accurate up to 100 GHz. Furthermore, a full-wave extraction method for the resistance–inductance–capacitance–conductance (RLCG) parameters of SDTSVs is also proposed in this paper, which can be applied to all of differential transmission lines. It is shown that the results of the RLCG parameters obtained from the full-wave extraction method agree well with that from the analytical calculation up to 100 GHz, further validating the accuracy of the proposed model. Finally, using the proposed model, a deep analysis of electrical characteristics of SDTSVs is carried out to provide helpful design guidelines for them in future 3-D ICs. [ABSTRACT FROM AUTHOR]

This letter presents an approach to design the fourth-harmonic mixer based on a pair of antiparallel Schottky diodes. To implement the proposed fourth-harmonic mixer, a two-level local oscillator (LO) low-pass filter is used to suppress the second, third, and fourth harmonics of the LO frequency, further to improve the isolation between RF and LO ports. Also, two shorted grounds are adopted to ensure the wideband performance of the proposed mixer. Furthermore, a wideband fourth-harmonic operating at 325–500 GHz is fabricated and measured. The results show that it has very low conversion loss from 15 to 22 dB in the whole operational band. [ABSTRACT FROM PUBLISHER]

This letter first proposes novel formulas for the calculation of the oxide capacitance and the silicon substrate capacitance in Tapered-Through Silicon vias (T-TSVs). The electric field is non-uniform distribution in T-TSVs due to its non-uniform three-dimensional structure. In order to get accurate formulas for the capacitance of T-TSVs, the conformal mapping method was used properly based on the analytical results of the local electric field structure in T-TSVs. When the slope angle equals to zero, the obtained formulas can be reduced to the formulas of cylindrical TSVs. The comparison between the results of the proposed formulas and the three-dimensional quasi-static field solver shows that the proposed formulas have very high accuracy, with maximum errors of 1% and 3% for the oxide capacitance and the silicon substrate capacitance, respectively. [ABSTRACT FROM PUBLISHER]

As the short vertical interconnections can significantly shorten the interconnect length between different circuits, three‐dimensional integrated circuits (3D ICs) based on the through‐silicon via (TSV) technology are considered as one of the most promising alternatives to overcome the scaling limits of Moore's low. Moreover, as the silicon technologies have been progressively expanded into the millimeter‐wave (mmW) realm, the TSV technology also provides a promising option to realize a compact system with high performance and operating frequencies. This article provides an overview of recent advances in the development of TSV technologies and silicon‐based passive devices for mmW applications. As various kinds of TSV losses are detrimental to the electrical performance of 3D ICs, especially in mmW systems, TSVs exploiting novel structures and materials still needs much more research, making it possible to integrate the passive device on 3D ICs and providing a promising option to realize a compact mmW system with excellent electrical performance and system reliability. [ABSTRACT FROM AUTHOR]

The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway is critical in cancer immunity. Autophagy is a highly conserved process that is responsible for the degradation of cytoplasmic material and is involved in both innate and adaptive immunity. Recently, cGAS-STING and autophagy have been shown to be interconnected, which may influence the progression of cancer. Although cGAS-STING and autophagy have been shown to be interrelated in innate immunity, little has been reported about cancer immunity. As cancer immunity is key to treating tumors, it is essential to summarize the relationship and interactions between the two. Based on this, we systematically sorted out the recent findings of cGAS-STING and autophagy in cancer immunity and explored the interactions between cGAS-STING and autophagy, although these interactions have not been extensively studied. Lastly, we provide an outlook on how cGAS-STING and autophagy can be combined, with the hope that our research can help people better understand their potential roles in cancer immunity and bring light to the treatment of cancer., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lu, Chen, Li, Zhu and Zheng.)