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Silicon-based devices, including the increasingly available SiGe-based devices, are now demonstrating f_T and f_MAX values over 200 GHz. These recent advances open the door to a wide range of silicon-based very high frequency, low power and highly integrated solutions. Trends in silicon MOS, SiGe HBT, SiGe MODFET and SiGe strained silicon FETs are reported. Silicon inroads to device functions viewed as the sole realm of III-V technologies are also being demonstrated. Capability and trends of the integrated silicon photodiode are reported here as an example. Integration of these high-speed devices into a complex circuit requires on-chip passive device functionality at such high frequency. Key devices to enable integration are the inductor, varactor, and transmission line, and operation of these devices at high frequency is reported. Further, we discuss noise isolation issues and techniques, which may be used when minimizing cross-talk within a conductive silicon substrate.

Flexible radio-frequency (RF) capacitors and inductors on the plastic substrates have been fabricated and characterized under mechanical bending conditions. A novel method to predict the RF performance for them on different bending states is demonstrated. Artificial neural network (ANN) shows good modeling accuracy for the flexible RF passive components with bending strains from dc to resonant frequency ($\sim 13/2$ GHz for the capacitor/inductor). More importantly, the automatically generated ANN model, with no need of repeatedly tuning the model parameters, has demonstrated the ability to predict the RF responses for the flexible capacitors and inductors under arbitrary bending conditions with only a few sets of experimental data. Once established, this model can automatically learn the structure of the input date and predict the actual results on specific bending state which can provide an original method to measure the performance for flexible electronics on even extreme bent radius. The ANN model indicates good potential for accurate design, characterization and optimization of the high-performance flexible electronics.

In this paper, a floating inductance and frequency-dependent negative resistance (FDNR) depending on the passive element selection is presented. The proposed circuit employs only plus-type second-generation current conveyors (CCII+s) as active elements, together with two resistors and two capacitors for realizing floating inductance and FDNR. Both of the capacitors in the floating inductance realization are grounded. Also, electronically tunable floating FDNR is obtained with the proposed circuit. The nonideality effects of the current conveyors on the proposed circuit are given. The proposed circuit is used in a low-pass ladder filter, and simulated with SPICE to exhibit its performance.

On-chip stacked-spiral radio-frequency (RF) inductor with vertical nanopowder-magnetic-core was proposed and implemented in standard 0.18 μm six-metal CMOS with a post-CMOS backend process module (i.e., CMOS+). To improve on the prior open-magnetic-circuit-loop structure and thus limited improvement at multi-GHz performance, the non-traditional concept shows vertical magnetic core forming a near closed magnetic loop. The ferrite nanoparticle-magnetic-core reduced magnetic loss to improve L-density to 9 GHz. Results show the proof-of-concept designs greatly increase the inductance, L, by up to 34% and the factor, Q, by 62% over a multi-GHz frequency range.

In this work, we use a new method to modify the properties of the silicon substrate through MEMS technologies, thus reducing the parasitic losses in high frequency. A 20μm thick SiO₂ layer with an air gap is firstly formed to reduce the parasitic resistance and capacitance in the low resistivity silicon substrate. Electroplating technology is used to deposit thick metal layer to reduce the series resistance due to the finite thickness of the conductor. And the performances of inductors fabricated on different substrates have been compared with each other. The electro-magnetic simulations have been performed in the work. It is found that the quality factors of such inductors can reach 15 and its self-resonance frequency is close to 10GHz. These can satisfy many RF applications.

Silicon-based devices, including the increasingly available SiGe-based devices, are now demonstrating f_T and f_MAX values over 200 GHz. These recent advances open the door to a wide range of silicon-based very high frequency, low power and highly integrated solutions. Trends in silicon MOS, SiGe HBT, SiGe MODFET and SiGe strained silicon FETs are reported. Silicon inroads to device functions viewed as the sole realm of III-V technologies are also being demonstrated. Capability and trends of the integrated silicon photodiode are reported here as an example. Integration of these high-speed devices into a complex circuit requires on-chip passive device functionality at such high frequency. Key devices to enable integration are the inductor, varactor, and transmission line, and operation of these devices at high frequency is reported. Further, we discuss noise isolation issues and techniques, which may be used when minimizing cross-talk within a conductive silicon substrate.