Our life depends on infrastructure network such as electricity, gas, and water, which then developed into communication network such as the internet, land phones and mobile phones to make us live comfortably in a secure and convenient life. In “Network Cloud”, it shows how we run our daily life with the connections between human and everything around us.
The development of silicon integrated circuits and its system has been driven by high functionality and high performance from miniaturization and this development has played an important role in charge of information communication networks, sensing, and energy distribution in Network Cloud. Today, researchers are working on a new device (beyond CMOS) in accordance to the minimum feature size of CMOS device (5nm), development focused on the CMOS integration (Miniaturization, known as More Moore by ITRS Roadmap) and novel physical phenomena.
Meanwhile, in order to improve functionality, not only in a limited sense of information processing, but there is also direction for high functionality by integration in between communication function and sensing function. It is not a mere miniaturization with high performance; it is an axis of a new technology called “High functionality in integration of diverse functionalities”. In ITRS roadmap, it is called “Integration with diverse functionalities” or “More than Moore”; different from miniaturization axis. Nowadays, there are competitive researches on development to produce technology with integration with diverse functionalities, for example by integrating RF chips and integrated chip parts for communications, integrated circuit sensor detection, actuators/integrated circuits, silicon photonics from integration of silicon CMOS technology and optical technology, integration in bio R&D and so forth. These are not something that can easily be created by simply combining existing technology, but should be done academically and scientifically for respective fields. Our laboratory acts as a collaboration platform for researchers from various academic fields to develop multifunction integrated chip on wafer provided by shuttle service, and through the research and development in multi-physics device (multifunction device/chip) used in Network Cloud, we aim to construct a new academic field for “Science and engineering of multi-physics device”.
The research on “Integration with diverse functionalities technology” is performed by collaboration between different fields of teachers and researchers off campus. In this group, our research focus on circuit technique such as those related with information transmission, platform and interface technology.

Keyword(s): Reconfigurable RF, Scalable RF, MEMS-Enhanced RF

With ‘one cellphone per person’ situation, it is predicted that everything will have their own communication functions. If it is to be fulfilled in an object, naturally it will be equipped with built-in sensor, and therefore circuit technique with lower power consumption, smaller size, and power supply that does not rely too much on battery life has become necessary.

In high frequency integrated circuits for communication, CMOS has high performance in accordance with technology scaling, but its operating voltage decreases with scaling. This is due to the reduced drain breakdown voltage and dielectric breakdown voltage, but this low voltage operation that determines the consumption power from power charging and discharging of the load capacity shows a positive effect in the digital CMOS integrated circuit. However, in analog circuit, it is directly linked to the difficulty to secure the dynamic range. Previously, passive components such as inductors and capacitors have been used in narrowband circuit, and the size of these components are determined by frequency used, therefore size of analog circuit on CMOS chip is very much affected. nH order inductor usually need more than 100μm square, but by using advance CMOS process and embedded processor, 200μm square inductor can be achieved. Since digital circuit cannot be mounted below the inductor, it consumes a comparatively large area on chip. Thus, passive components cannot be reduced in area in accordance with CMOS technology scaling in RF CMOS integrated circuit, and as a result we face a problem where it has no advantage in cost reduction benefits in miniaturization. Furthermore, reconfigurable circuit technique to accommodate cognitive communication technology has become necessary to support multiple wireless standards. In this study, we are developing circuit technique which only consists of MOSFET (active component), and yet, it is a wideband operational Scalable RF CMOS circuit. ‘Scalable’ here means as the utilized CMOS technology generation progressed, the circuit also shows improvement in size consumption, as well as its performance. One of RF CMOS circuit direction is SoC with digital circuit. In effort to SoC, it is important to secure the scalability in analog CMOS circuit and RF CMOS circuit.

Besides, it is said that the only successful business in integrated circuit up until now is in the mass production of small kind of memory and MPU. The fact that miniaturization of integrated circuit are facing many challenges means that there is a change of perspective on the direction of development which is good. Disruptive innovation suggests an interesting idea. Instead of following the high-end market demand, “drop performance” and try to develop a new low-end market is a theory that proves that actually a sustainable technology can destroy high-end market imperceptibly. As an engineer, “dropping performance” is an uncomfortable part of it, but in CMOS technology development, rather than using advance CMOS, trying to practically use mature CMOS technology and this disruptive innovation might be able to produce integration with diverse functionalities. Integrations such as of MEMS and CMOS, CMOS and packaging technologies are considered to be an interesting exit. “MEMS-Enhanced RF Circuit” group is doing research development and aims to improve RF circuit performance by using MEMS technology significantly.

Keyword(s): On-chip transmission line, High efficiency signal transmission, High frequency measurement technology, De-embedding technique (up to 110GHz)

In recent years, multicore processor equipped with multiple CPU on a chip for high-end processor has become the mainstream. In addition, reports on Network on Chip which consists of network between dozens of CPUs on a chip have been presented in conferences. One of the challenges in this high-end digital integrated circuit is that the interconnection among and within chips limits the performance of the entire system. For instance, to improve the bandwidth and latency of the on-chip bus/on-chip network, number of buffer (repeater) will increase and hence, it will consume more power.
This group is doing research on how to improve bandwidth and latency of on-chip interconnection, together with energy efficiency for high-speed signal transmission circuit. It is not as simple as just using CMOS inverter for buffering like digital circuit; we also have to consider the electromagnetic and electrical characteristics of the interconnection besides the analog behavior of the signal. With analog circuit and RF application in in-chip bus/on-chip network, we are developing methods on how improve channel energy efficiency and its effective bandwidth. Specifically, we pursue research on De-embedding technology to eliminate the unnecessary parasitic elements component from measurement results of on-chip transmission interconnection technology, high-efficiency small area equalization technology, high speed and low power MUX / DEMUX circuitry that utilized the inductance component in interconnection.

Keyword(s)：Microelectromechanical System (MEMS), Fushion technique，Shuttle service

To sustain development of society and industry as well as avoid global warming, we need to find way for Green (low calorie consumption, low environmental impact), Dependable (high performance, high reliability, high safety), ECO (eco-friendly) society Neural Networks (Information Network System) and social vascular network (the energy network system, transportation system). Through this, advancement and high reliability of the society and the whole industry is aimed to be well-balanced with energy-saving, CO2 control and ECO. We breakthrough the obstructed economic situation to create a sustainable advanced information and energy-oriented society, and with joint effort between industry and academia, we try to achieve significant research findings that will contribute to new industries.

● Network analyzer
・Agilent, E8361A & N5260A & N5260-60003/60004, 10M-110GHz
・Agilent, N5245A, 10M-50GHz, 4port
・Agilent, E8364B & N4421B, 10M-50GHz, 4port
・Agilent, E5071C, 100k-8.5GHz, 4port
・Agilent, 8720ES, 50M-20GHz

● Signal generator
・Agilent, E8257D, 250k-67GHz
・Anritsu, MG3700A, 250k-6GHz
・Agilent, E4438C, 250k-6G
・Anritsu, MG3700A, 250k-6G

● Spectrum analyzer
・Agilent, E4448A, 3-50GHz
・Agilent, 8563EC, 9k-26.5GHz

● Vector signal analyzer
・Agilent, 89600S, DC-6GHz

● Signal source analyzer
・Agilent, E5052B & E5053A, 10M-26GHz
・Agilent, E5052A, 10M-7GHz

● Noise figure analyzer
・Agilent, N8975A

● Bit-error-rate test system
・Agilent, Pulse pattern generator, E8403A & E8491B & E4808A & E4861A x8 & E4868B, 〜40Gbps
・Agilent, Error detector, E8403A & E8491B & E4808A & E4861A x8 & E4869B, 〜40Gbps
・Anritsu, Signal Quality Analyzer, MP1800A x2, 0.1-25Gbps
・Anritsu, Pulse pattern generator, MP1761A x2, 50M-12.5Gbps
・Anritsu, Error detector, MP1762A, 50M-12.5Gbps

● Sampling oscilloscope
・Lecroy, SDA100G & SE-100 x2, 〜100GHz
・Agilent, 86100C & 86117A & 86107A, 〜50GHz

● Semiconductor parameter analyzer
・Agilent, E5270B & E5287A x4 & E5281B x4
・Agilent, E5270B & E5281B x8
・Agilent, E5270A & E5281A x8

● RF prober station x 4

● Substrate manufacturing equipment
・MITS, FPZ-31ATHP model 60

● Computing machineries
・Computer server x 10 (CPU 3GHz x 4 core, 48GB memory), file server etc
・Cadence・Mentor・Synopsys Tools, HFSS, GoldenGate, MATLAB, Coventor Ware etc