Research/NEXT Poster Report

2019-02-17 (日) 23:41:03 (120d)

This page contains the poster presented at the FIRST Symposium in Tokyo, 1 March, 2014.


English Plain Text Version


Integrated MEMS Technology for Multi-functional Low Power Electronics

内閣府/日本学術振興会 最先端・次世代研究開発支援プログラム
Funding Program for Next Generation World-Leading Researchers (NEXT Program) granted by The Japan Society for the Promotion of Science (JSPS) initiated by The Council for Science and Technology Policy (CSTP)
研究代表者: 東京大学 先端科学技術研究センター 年吉 洋
PI: Hiroshi Toshiyoshi, RCAST, The University of Tokyo

Contribution of This Work

1. Background and Scope



Integrated MEMS is a technology to assemble microscopic "machines" with electronic sensors and circuits by using the semiconductor micro fabrication technique. Integrated MEMS is expected to be an enabling power for the next generation high added value manufacturing technique as well as for the low power consumption technology. However, the R&Ds in the MEMS field are ensemble of vast wide range of case studies due to the lack of systematic design and production schemes. For this reason, this study focuses onto the standardization of the integrated MEMS such that we would have a technological perspective from the material level to the system.

参考文献: 年吉 洋、「集積化MEMSのための解析・設計・製作技術プラットフォーム」 第23回マイクロマシン/MEMS展同時開催プログラム「半導体企業のためのMEMS講座」(専門講演)、2012年7月11日、東京ビッグサイト

2. Design Platform for Integrated MEMS (Equivalent Circuit Co-solver)


MEMS機械構造を有限要素法で解析しても、ノード点数が多すぎるために電気回路との統合設計ができません。 そこで本研究では、電気回路シミュレータ上でMEMS機械構造の等価回路(運動方程式)を解く手法を構築し、フリーウェアとして一般公開しました。 また、世界標準回路設計CADのCadenceにも移植しました。

FEM is a powerful tool for MEMS but is also difficult to co-solve with elecrical circuit for transient analysis due to a large number of data nodes. For this reason, we have newly developed a co-solving technique for integrated MEMS by using an equivalent circuit solve for the mechanical equatio of motion, which is now available from our homepage. Also, we have developed a version for Cadence Virtuoso, which is a defacto standard as a VLSI CAD.

Reference: T. Konishi, K. Machida, S. Maruyama, M. Mita, K. Masu, and H. Toshiyoshi, IEEE/ASME J. Microelectromech. Syst., vol. 22, no. 3, Jun. 2013, pp. 755-767.

3. Fabrication Process for Integrated MEMS (Post CMOS MEMS Process)


幅広く使える集積化MEMSプロセスとして、CMOS集積回路を製作した後のウエハに金属薄膜(スパッタ等)や金属メッキ膜を用いてMEMS構造を製作する手法を開発しました。 その応用例として、集積回路中の不要な電源を遮断する静電駆動型パワーゲートスイッチや、高周波無線通信用の可変容量などを設計・製作しました。 また、MEMS素子を用いてNOT、NAND、NOR、XOR、XNOR等の論理演算が可能であることを理論的・実験的に検証しました。

As a multi-purpose process for integrated MEMS, we have developed a surface micromachining technique on a pre-fabricated LSI by using sputtered/electroplated metals. The process capability has been verified by demonstrating an electrostatic type power-gating switch that shuts down the unneeded electrical current flowing in an LSI. We also have demonstrated an RF-MEMS switch for wireless transmitters. Another demonstration has been made to prove an idea to use the MEMS electrostatic mechanism for logic operation such as NOT, NAND, NOR, XOR, and XNOR with a single cantilever beam.

Reference: M. Mita, M. Ataka, and H. Toshiyoshi, “Microelectromechanical XNOR and XOR logic devices,” IEICE Electronics Express, vol. 10, no. 8, 2013, pp. 1-12.
(This work was performed in collaboration with ISAS/JAXA.)

4. Multi-User Integrated MEMS Processes (Wafer Shuttle Sharing)


LSIウエハを丸ごと作ろうとすると膨大な費用が発生します。また、どこの大学にもMEMSプロセス施設があるとは限りません。 そこで本研究では国内のLSI製造企業が提供するウエハ共有方式のシャトルサービスを利用して回路を設計し、その上にMEMS構造を集積化する手法を研究しました。 また、本研究経費によりMEMSポストプロセスの装置を導入し、産学の共同研究者グループが共同で利用できる体制を整備しました。

It would cost a lot if one place an order of VLSI wafer for himself. MEMS production facilities are also expensive to install. For these reasons, we used a wafer shuttle service operated by Japanese comapanies to share a wafer with plural users to save the cost. We also used the budget of this project to install the post-CMOS processing equipment in the lab such that our collaborator would share the MEMS processes.

Reference: NTT~AT (0.18, 0.35 and 0.6 um), VDEC Rohm (0.18 um), VDEC-Fenitec (0.6 um).


A. Cognitive Wireless Communication (RF-MEMS Variable Capacitor for VCO)


コグニティブ無線通信とは、通信帯域の使用状況等をつねにモニタして、最適な通信条件になるように機器の周波数やアンテナ接続方向などをチューニングする通信方式のことです。 本研究ではRF−MEMS(Radio Frequency - MEMS)技術により静電駆動型の可変デジタルキャパシタを製作し、それを800MHz帯の周波数可変発振回路に応用しました。 本研究は、日本無線株式会社との共同研究として実施しました。

駆動電圧35V、容量値0.55〜0.73pF、1〜4ビット構成、VCOのQ値60、位相ノイズ -101dBc/Hz

Cognitive wireless communication is a way to optimize the system (frequency, radiation patterns) by monitoring the traffic. In this work, we have developed a MEMS electrostatic tunable capacitor and used it in an 800 MHz band VCO (voltage Controlled Oscillator).

This work was performed in collaboration with Japan Radio Corporation.

Data: operation voltage 35V, capacitor range 0.55-0.73pF, control 1-4 bit, VCO quality factor 60, phase noise -101dBc/Hz.

Reference: K. Urayama, K. Akahori, N. Adachi, H. Fujita, and H. Toshiyoshi, "A Low Phase-Noise VCO for Multi-Band Transceiver using Fully Packaged MEMS Electrostatic Varactors," in Proc. 26th IEEE Int. Conf. on Micro Electro Mechanical Systems, Jan. 20-24, 2013, Taipei, Taiwan, pp. 737-740.

B. Event/Personal Monitoring (High Sensitive MEMS Accelerometer)


加速度センサの応用先は、スマートフォンを超えてさらに広がります。近い将来には、すべての人工物に加速度センサをつけて、モノ・ひとの動きを検出することで人間の生活をアシストする時代が来るでしょう。 そこで本研究では、人間の動きに合わせて1G未満から数Gの広範囲の加速度を検出可能なセンサを集積化MEMSで実現しました。



Application field of MEMS accelerometers would go beyond the smartphone hardware, and a lot of MEMS sensors would be used to monitor the events and persons to help our life. In this work, we have developed a MEMS accelerometer that could sense a wide range of acceleration including sub 1G to a few G's by using the integrated MEMS.

This work was performed in collaboration with NTT Advanced Technology Corporation and with Professor K. Masu's group with the Tokyo Institute of Technology.

Data: 0.35um CMOS, Vdd = 3.3V, acceleration range 0.5G - 6G, low Brownian noise of 11.7uG/Sqrt(Hz) due to high density material (plated gold).

Reference: T. Konishi, D. Yamane, T. Matsuhsima, K. Machida, K. Masu, and H. Toshiyoshi, "An arrayed accelerometer device of a wide range of detection for integrated CMOS-MEMS technology," Jpn. J. Appl. Phys., vol. 53, 027202, 2014, pp. 027202.1-027202.9.

C. Micro Display for Everywhere (Laser Scan MEMS Image Display)


RGBのレーザー光をMEMS光スキャナで走査すると、どこにでも焦点のあう超小型の投写型画像ディスプレィを構成できます。しかも、描画用のレーザー光源をそのまま用いて、レーザー距離計測も可能です。 この特徴を生かして、スクリーン位置やユーザーの身振り手振りを検出して画像を制御するタイプのインタラクティブ画像ディスプレィを作りました。



A focus-less image projector can be constructed by using a MEMS optical scanner to spatially scan the collimated RGB beams from laser diodes. The identical optical can also be used as a laser range finder to measure the distance to the screen or to detect the object such as a user's hand inserted in front of the screen. We used this feature to create a new type of user-interactive display that could change the projected images by the viewer's physical motion.

This work was performed in collaboration with Stanley Electric Corporation.

Data: scanner drive voltage 40V, image VGA class, range 20-60cm, resolution 2cm.

Reference: Sungho Jeon, Hiroyuki Fujita, and Hiroshi Toshiyoshi, "A MEMS Interactive Laser Projection Display with a Built-in Laser Range Finder," in Proc. IEEE Int. Conf. on Optical MEMS and Nanophotonics (OMN 2013), Kanazawa, Japan, Aug. 18-22, 2013, pp. 21-22.

D. OCT Medical Inspection Gear (MEMS Tunable Wavelength Light Source)


赤外光の波長可変光源は光ファイバ通信用途だけでなく、医療用の光断層観察(OCT=Optical Coherence Tomography)にも広がりつつあります。 本研究では高速で動作するMEMS光スキャナを開発して、動画像も撮影可能なOCTシステムを構成しました。



MEMS tunable light source is not limited to the optical fiber applications but also used in the medical field such as OCT (Optical Coherence Tomography). We have developed a fast optical MEMS scanner to sweep the wavelength of the OST system such that a motion picture can be captured.

This work was performed in collaboration with Santec Corporation.

Data: scanner operation voltage 70V, scanner resonance 70kHz, wavelength sweep 140kHz, center wavelength 1300nm, bandwidth 100nm, output power 20mW, OCT inspection depth 2mm, image resolution 5-10um, frame rate 50fps.

Reference: K. Isamoto, K. Totsuka, T. Sakai, T. Suzuki, A. Morosawa, C. Chong, H. Fujita, and H. Toshiyoshi, "High Speed MEMS Scanner Based Swept Source Laser for SS-OCT," IEEJ Trans. Sensors and Micromachines, vol. 132, no. 9, 2012, pp. 254-260. (in Japanese)

Perspective of This Work for 2030

Harvesting Unharnessed Energy for Trillion Sensor Era


近い将来に、地球上で年間1兆個ものセンサを消費する「トリリオン・センサ」時代が到来すると言われています。これは東京都の面積と人口で言うと、距離1メートルに1個の割合でセンサが存在することを意味しています。 そのような時代に必要な技術として、本研究で実施したようなMEMSセンサ技術・無線通信技術のほかに、電力線や1次電池に頼らずにエネルギを供給する技術が挙げられます。

It is said that we will soon see a new era to produce a trillion of sensors a year for monitoring. This vast amount is equivalent to sensors distributed every 1 meter in the Tokyo downtown, considering the 13M population living in the 2,200km^2. Besides the MEMS sensor and wireless technologies, we will soon need a new scheme to supply energy to such small and many sensors without using wires or batteries.


半導体集積回路の微細化にともなって、LSIの消費電力は年々低くなっています。一方MEMS分野では、風や振動などの環境から発電するエナジー・ハーベスト技術の研究が進められています。 現在研究代表者らが取り組み中の永久電荷(エレクトレット)形成技術や静電容量増大技術により、2030年頃には至近距離(10メートル)無線通信型センサーノードのエネルギーは、MEMS型の振動発電機で供給できるようになるでしょう。

Power consumption of VLSI is becoming smaller every year owing to the downsizing of the circuit patterns. New resource of power is also developed in the field of MEMS by harvesting from the natural vibrations such as winds and infrastructures. In addition to the work reported here, we also develop a new technique to integrate permanent electrical charge (electret) and to increase the capacity of the electrical energy storage. By year 2030, people might see a new world where the wireless sensor nodes of short distance (10 meters) are power-supplied by the MEMS energy harvesters.



This research is granted by the Japan Society for the Promotion of Science (JSPS) through the "Funding Program for Next Generation World-Leading Researchers (NEXT Program)," initiated by the Council for Science and Technology Policy (CSTP).

From NEXT Summary Report


集積化MEMS技術による機能融合・低消費電力エレクトロニクス Integrated MEMS Technology for Multi-functional Low Power Electronics