International Technology Roadmap for Semiconductors 2003の要求清浄度について － シリコンウエハ表面と雰囲気環境に要求される清浄度, 分析方法の現状について －

IEEE Antennas and Wireless Propagation Letters

With the development of the Internet of Things (IoT), the demand for thin and wearable electronic devices is growing quickly The essential part of the IoT is communication between devices, which requires radio-frequency (RF) antennas Metals are widely used for antennas; however, their bulkiness limits the fabrication of thin, lightweight, and flexible antennas Recently, nanomaterials such as graphene, carbon nanotubes, and conductive polymers came into play However, poor conductivity limits their use We show RF devices for wireless communication based on metallic two-dimensional (2D) titanium carbide (MXene) prepared by a single-step spray coating We fabricated a ~100-nm-thick translucent MXene antenna with a reflection coefficient of less than −10 dB By increasing the antenna thickness to 8 μm, we achieved a reflection coefficient of −65 dB We also fabricated a 1-μm-thick MXene RF identification device tag reaching a reading distance of 8 m at 860 MHz Our finding shows that 2D titanium carbide MXene operates below the skin depth of copper or other metals as well as offers an opportunity to produce transparent antennas Being the most conductive, as well as water-dispersible, among solution-processed 2D materials, MXenes open new avenues for manufacturing various classes of RF and other portable, flexible, and wearable electronic devices

https://advances.sciencemag.org/content/advances/4/9/eaau0920.full.pdf

2D titanium carbide (MXene) for wireless communication

This paper presents an in-depth analysis toward understanding the business value components an organization can derive from adopting radio frequency identification (RFID). Although this subject is currently a hot topic, many organizations are slow in warming up to the idea of using RFID to conduct more effective and efficient business processes. We propose a framework for evaluating the business value of RFID technology, hoping that a better understanding of the business value of RFID will encourage more organizations to implement it. Emphasis is on delivering business value through refining business processes and expanding the business model. We illustrate these concepts drawing on the experience of five early adopters from the Taiwan healthcare industry and formulate this framework as a set of propositions based on relevant literature, cases from pioneers in the field and our intuition. These propositions will need to be validated through empirical evidence. r 2007 Elsevier B.V. All rights reserved.

/pdf/evaluating-the-business-value-of-rfid-evidence-from-five-44860d0jh3.pdf

Evaluating the business value of RFID: Evidence from five case studies

Energy Filtering of Charge Carriers: Current Trends, Challenges, and Prospects for Thermoelectric Materials

In-plane Seebeck coefficient of porous Si free-standing membranes of different porosities was accurately measured at room temperature. Quasi-steady-state differential Seebeck coefficient method was used for the measurements. A detailed description of our home-built setup is presented. The Seebeck coefficient was proved to increase with increasing porosity up to a maximum of ~1 mV/K for the ~50 % porosity membrane, which is more than a threefold increase compared to the starting highly doped bulk c-Si substrate. By further increasing porosity and after a maximum is reached, the Seebeck coefficient sharply decreases and stabilizes at ~600 μV/K. The possible mechanisms that determine this behaviour are discussed, supported by structural characterization and photoluminescence measurements. The decrease in nanostructure size and increase in carrier depletion with increasing porosity, together with the complex structure and morphology of porous Si, are at the origin of complex energy filtering and phonon drag effects. All the above contribute to the observed anomalous behaviour of thermopower as a function of porosity and will be discussed.

https://link.springer.com/content/pdf/10.1186%2Fs11671-016-1411-z.pdf

High Seebeck Coefficient of Porous Silicon: Study of the Porosity Dependence.

The effects of RF hot-carrier stress on the characteristics of 60-GHz power amplifiers (PAs) on a CMOS 65-nm process are investigated, for the first time, in this letter. A reliability study is made on a one-stage PA to validate an aging model and the degradation explanation. A drop of 16% of the gain, 17% of the 1-dB output compression point (OCP1 dB), and 17% of the Psat are measured at 60 GHz after 50 h of stress under Vdd = 1.65 V with Pin = 0 dBm and Vdd = 1.9 V with Pin = -10 dBm at 60-GHz frequency.

Hot-Carrier Stress Effect on a CMOS 65-nm 60-GHz One-Stage Power Amplifier

An improved analytical model of the CMOS 65-, 45-, and 32-nm silicon technology integrated transmission line is proposed. This model is derived from previous classical ones used for printed circuits board lines. Improvements have been performed to take into account the size of integrated lines. The study is validated up to millimeter-wave frequencies for different linewidths realized with various metal levels. Accurate results allow the model to be implemented in commercial computer-aided design software commonly used for millimeter-wave designs. A comparison with commercial tools is carried out.

65-, 45-, and 32-nm Aluminium and Copper Transmission-Line Model at Millimeter-Wave Frequencies

A compact low-loss microstrip diplexer that forms by two band-stop filters using interdigital capacitor and a stepped-impedance resonator structure when joined by a miniature T-junction is introduced. The diplexer operates at global system for mobile communication frequency 1800 MHz and 2.45 GHz WLAN frequency which are the most available frequency bands for RF energy harvesting applications. Simulated and measured results are in very good agreement with low insertion loss of 0.4 dB and high selectivity characteristics.

Compact low-loss microstrip diplexer for RF energy harvesting

A millimeter-wave Power Amplifier (PA) implemented in a 65nm CMOS process with 8-metal layers and transistor f T /f MAX of 160/200 GHz is reported. The PA operates from a 1.2V supply voltage. A power gain of 13.4 dB, an output P1dB of 12.2 dBm with 7.6 % PAE and a saturated output power of 13.8 dBm at 58 GHz are measured. S 11 and S 22 are lower than 10 dB, which ensures an input and output matching to a 50 Ω impedance. These results are obtained thanks to accurate millimeter wave models for MOS and integrated microstrip lines used as passive components. The amplifier design takes electromigration constraints at 105°C into account. Excellent agreement between measurement and simulation results is observed.

Philippe Benech

Papers

High Seebeck Coefficient of Porous Silicon: Study of the Porosity Dependence.

Hot-Carrier Stress Effect on a CMOS 65-nm 60-GHz One-Stage Power Amplifier

65-, 45-, and 32-nm Aluminium and Copper Transmission-Line Model at Millimeter-Wave Frequencies

Compact low-loss microstrip diplexer for RF energy harvesting

A CMOS class-A 65nm power amplifier for 60 GHz applications