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In recent years, radio frequency (RF) systems have been moving towards miniaturization. Traditional wire-bonding technology used in RF systems have significant disadvantages in terms of parametric inductance and package size scaling-down. Therefore, people pay more attention to the high-performance and small-size interconnection schemes of RF systems. In this regard, we designed a series of micro bumps arrays for RF application, including arrays with diameters of 15 μm / 30 μm / 40 μm and a pitch of 30 μm / 60 μm / 80 μm. To study RF property of micro bumps array, Cu / Sn micro bumps arrays jointed double-layer coplanar waveguide (CPW) structures were prepared and tested. By subtracting the insertion loss of CPW line from the test structure's insertion loss, the insertion loss of the micro bumps array can be obtained. Comparing the insertion loss of micro bumps arrays with different diameters, the insertion loss of the micro-bumps array with a diameter of 15 μm is the smallest, and the micro bumps with multiple rows have lower insertion loss than a single micro bump. Among them, the insertion loss of a 3 × 6 micro bumps array with a diameter of 15 μm after bonding is 0.15 dB@40GHz.

This paper proposes a vertical coaxial transmission structure made of a centered Cu TSV surrounded with a cycle of TSVs as grounding shield. To verify the feasibility, a set of vertical coaxial transmission structure linked with CPW lines is designed to be able to work at 40GHz and parametric study is conducted in the meantime. By changing the diameter of the grounded TSV ring array and the space of centered RF TSVs, the results show that test structures have good high frequency transmission performance; the larger the diameter of the grounded TSV ring array, the better the transmission performance; the S21 parameter does not change significantly when the space between the two centered RF TSVs is changed. With developed TSV process, sample is fabricated and tested. The insertion loss is less than 1.2dB@40 GHz for the two vertical coaxial transmissions structures linked with CPW lines, and it can be derived that it has a less than 0.15dB@40GHz for a single coaxial transmissions structure.

This paper proposed a three-dimensional integrated RF transceiver module based on high resistivity Si interposer embedded with microchannel for on-site heat dissipation. It's composed of three stacked layers of TSV interposer, including the bottom one embedded with microchannels for on-site cooling which has four high power chips assembled on its top side, the middle one having four large cavities to accommodate the chips assembled on the bottom one which is utilized as a supporting layer, the top one having a IC driver chip mounted on its top side. In order to study its thermal property, a simplified thermal resistance network is built and analysis is done. To validate this method, finite element simulation is conducted and the results show that maximum deviation of the temperature rise of each high power chip mounted on the bottom Si interposer referring to coolant is 9.04% and minimum deviation is 4.85% in the range from 0.1m/s to 1m/s for DI coolant.

TSV technology enables small size, high density, high integration, and high performance 3D integration. Currently, its application or even commercialization is occurring in Memory IC, high performance logic IC, and MEMS, microwave and millimeter wafer application will become an emerging field in coming years with booming of the 5G, millimeter wave radar. For high frequency application, TSV interposer based 2.5D/3D integration is a competitive choice. This paper proposes a dual redundant TSV interconnection design in High resistivity Si interposer for Millimeter Wave Applications. To verify the feasibility of this design, a set of test structures that can work at millimeter wave is designed, which is made of dual redundant TSV interconnection linked CPW lines. Process is developed for High resistivity Si TSV interposer and Test structures are fabricated and tested, the results show that the insertion loss of the test structure with dual redundant TSV interconnect is

Expert authoritative value is the quantitative criteria in online group argumentation support systems. A comprehensive method of calculating expert authority value is proposed in this paper by analyzing the professional title, the highest educational background, the number of seminars attended and the behavior of experts in the argumentation. The experimental results show that the algorithm is reasonable and the method is effective in judging the level of experts. In the argumentation system, the method of calculating expert authoritative value provides good condition for experts to interact in the integrated seminar environment.