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This paper presents a miniaturized multi-layer Marchand Balun realized by low temperature co-fired ceramic (LTCC) technology for wireless application. In order to seize the advantage of LTCC technology on multi-layer substrates and make full use of three-dimensional space to develop small size device, the broadside coupled strip line is utilized to design the coupled region of the Marchand Balun. A method of changing the even mode impedances of the coupling region is proposed that can optimize the design of the Marchand Balun to get a better operating performance. This paper proves that the proposed method is feasible and the performance of the Marchand Balun is suitable for wireless application.

A rapid and sensitive high performance liquid chromatography — tandem mass spectrometry (HPLC-MS/MS) method for determination of gibberellin(GA3) residue in vegetables and fruits was developed. The gibberellin in samples were extracted with methanol solution, adjusted the pH value 3–4, and then extracted with ethyl acetate. After the evaporation, the organic phase was purified with solid extraction using C18 column. The purified liquid was detected using HPLC-MS/MS and quantified using external standard method. Linear range of gibberellin was between 0.01∼10.0 μg/mL, and the detection limit was 0.01 μg/mL. The recoveries for all samples with gibberellin ranging 0.02∼1.0 mg/kg were between 77.0∼100.0%. The CV value were between 3.39∼10.05 %(n=5). The results show that the method was accurate and of low detection limit, and could satisfy the request of MRL determination.

A quantitative and quantitative method was established for determining 5 flavonoids in honeys by high performance chromatography-tendemmass/mass(HPLC-MS/MS). The samples were dissolved by deionized water, and then extracted by hexane-ethyl acetate solution with volume ratio of l:l, and the extract were centrifuged and evaporated. The residue were dissolved by methanol. The chromatography separation was performed on a C18 column with a gradient elution programmer using the mixture of methanol and 0.1% aqueous formic acid as mobile phase. The mass spectrometry equipped with an electrospray ionization source(ESI) was operated in the negative mode using multiple reaction monitoring(MRM). The linear relationship of the method was very obvious and the 5 flavonoids limits of quantization (LOQ) were 1.5μg/kg, the average spike recoveries situated between 64%∼89%, and the relative standard deviation(RSD) were 2.2%∼8.4%. The method is outstanding due to its precision and excellent separation effect and can be used for the determination of flavonoids in honey.

This paper presents a miniaturized multi-layer lowpass filter with sharp roll off suppression rate beyond the passband realized by low temperature co-fired ceramic (LTCC) technology for microwave application. By improving the prototype filter structure, three transmission zeros can be introduced to achieve sharp suppression rate. The proposed filter is designed with a cut-off frequency of 1.40GHz and the measured insertion loss is less than 0.6dB. The attenuation is less than −40 dB above 1.6GHz, and the bandwidth between the cutoff frequency and 1.6 GHz is only 200MHz. The three transmission zeros are obtained at 1.63GHz, 1.86GHz, 2.6GHz respectively. Due to the multi-layer structure, the size of this miniaturized filter is 3.2mm*2mm*1.41mm. This paper proves that the proposed filter is suitable for microwave application.

We present an accurate through silicon via (TSV) thermal mechanical stress analytical model which is verified by using finite element method (FEM). The results show only a very small error. By using the proposed analytical model, we also study the impacts of the TSV radius size, the thickness, the material of Cu diffusion barrier, and liner on the stress. It is found that the liner can absorb the stress effectively induced by coefficient of thermal expansion mismatch. The stress decreases with the increase of liner thickness. Benzocyclobutene (BCB) as a liner material is better than SiO2. However, the Cu diffusion barrier has little effect on the stress. The stress with a smaller TSV has a smaller value. Based on the analytical model, we explore and validate the linear superposition principle of stress tensors and demonstrate the accuracy of this method against detailed FEM simulations. The analytic solutions of stress of two TSVs and three TSVs have high precision against the finite element result.

Through silicon via (TSV)–TSV coupling is detrimental to the performance of three-dimensional (3D) integrated circuits (ICs) with the major negative effect of introducing coupling noise. In order to obtain an accurate estimation of the coupling level from TSV–TSV in the early design stage, this paper first proposes an impedance-level model of the coupling channel between TSVs based on a two-port network, and then derives the formula of the coupling coefficient to describe the TSV–TSV coupling effect. The accuracy of the formula is validated by comparing the results with 3D full-wave simulations. Furthermore, a design technique for optimizing the coupling between adjacent coupled signal TSVs is proposed. Through SPICE simulations, the proposed technique shows its feasibility to reduce the coupling noise for both a simple TSV–TSV circuit and a complicated circuit with more TSVs, and demonstrates its potential for designers in achieving the goal of improving the electrical performance of 3D ICs.

This paper presents a theoretical study of the pulse-width effects on the damage process of a typical bipolar transistor caused by high power microwaves (HPMs) through the injection approach. The dependences of the microwave damage power, P, and the absorbed energy, E, required to cause the device failure on the pulse width τ are obtained in the nanosecond region by utilizing the curve fitting method. A comparison of the microwave pulse damage data and the existing dc pulse damage data for the same transistor is carried out. By means of a two-dimensional simulator, ISE-TCAD, the internal damage processes of the device caused by microwave voltage signals and dc pulse voltage signals are analyzed comparatively. The simulation results suggest that the temperature-rising positions of the device induced by the microwaves in the negative and positive half periods are different, while only one hot spot exists under the injection of dc pulses. The results demonstrate that the microwave damage power threshold and the absorbed energy must exceed the dc pulse power threshold and the absorbed energy, respectively. The dc pulse damage data may be useful as a lower bound for microwave pulse damage data.