Overseas Trends

3rd Japan-Korea-China MEMS Standardization Workshop
In order to speed up the design and development process,ensure compatibility and make mass production possible,
MEMS international standardization will be crucial. In Japan,
the Micromachine Center has played a leading role in pursuinginternational standardization with the International
Electrotechnical Commission (IEC). So far three international
standards originating in Japan have been published: Terms anddefinitions, Tensile testing method of Thin film materials andThin film standard test piece for tensile testing. Anotherproposed standard, Thin Film Fatigue Test Methods, iscurrently under review as a Committee Draft Version (CDV).
Against this backdrop, the first Japan-Korea-China MEMS
Standardization Workshop was held in Tokyo in 2005 as a forum
for the exchange of information and the promotion of cooperationon the part of Japan, South Korea and China with regard to MEMS
standardization. Last year, a second workshop was held inGyeongju, South Korea. Thisyear, the third MEMS
Standardization Workshop
was held on June 28, 2007 tocoincide with the IEC TC47
Beijing Conference. Twospeakers each from Japan,
South Korea and China gavea total of six presentations onthe evaluation of material
properties for MEMS thinfilm materials. TheseThe Tian You Hotel (the venue
presentations were followedfor the Japan-Korea-China MEMS
Standardization Workshop)
by a spirited discussion.

bonding strength of MEMS
materials, a new project
aimed at standardization
has just been initiated inJapan as well, and thispresentation played amajor role in promoting
this project to South
Korea and China.
(4) Dr. C. S. Oh of the Kumoh National Institute of Technology
in South Korea gave a presentation on the measurement ofthermal expansion in thin film materials using laserinterferometry. This is an area in which not much researchhas been promoted in Japan, and thus the presentation wasof considerable interest. Moreover, as South Korea plans topropose this method of measuring thermal expansion as aninternational standard, it is one for which study will beneeded in Japan as well.
(5) Dr. Isono of Ritsumeikan University gave a presentation
centering on the results of bending tests of nanosize
thickness single-crystal silicon thin films. In particular, Dr.
Isono presented a great many test results to show that, withsubmicron thicknesses,
the silicon exhibits
plastic deformation evenat room temperature.
This is an extremely
important finding interms of applications for
MEMS/NEMS, and it
attracted a great deal ofattention.
(6) Dr. Ren of Tsinghua University gave a presentation focusing
on the progress of MEMS research at Tsinghua University.
His presentation communicated the enthusiasm with which
MEMS research is being conducted at Tsinghua University
as well.

The following is an overview of the presentations.
(1) J. H. Kim of the Korea Institute of Machinery and Materials(KIMM) gave a presentation on the preparation of test
specimens and test methods relating to compression testingof micro/nano pillar shaped test specimens fabricated fromthin films. Dr. Kim also presented the results ofmeasurement of polymer and metal thin films. South Korea
will propose this material test method as a standard
originating in South Korea.
(2) Dr. Zhao of the Chinese Academy of Sciences gave apresentation on the degree of elasticity and fracture
toughness of MEMS and bio-MEMS thin film materials. With
regard to the degree of elasticity, Dr. Zhao demonstrated
analytically that when the thickness of the thin film is lessthan an atomic layer of 100, a size effect becomes evident in
the Young’s modulus due to the surface energy of the material.
(3) Dr. Higo of the Tokyo Institute of Technology gave apresentation on the evaluation of bonding properties for
MEMS materials. Dr. Higo focused in particular on a
discussion of new phenomena that are the opposite of theordinary size effect – for example, with regard to the size
dependency for the bonding strength between polymer (SU8) and silicon boards, the strength is sometimes reduced
when the size is small – as well as the causes for these newphenomena. With regard to methods for measuring theThis is the third time the Japan-Korea-China MEMS
Standardization Workshop has been held. The majorachievement of the Workshop is its role in providing a forum forthe exchange of information regarding the current state of
MEMS standardization and future prospects in each country, as
well as enhancing the common recognition in these threecountries. It is crucial that these achievements be utilized in
MEMS standardization strategies in Japan. Moreover, most of
the presentations in the Workshops held up to now havefocused primarily on evaluating the properties of MEMS
materials. In the future, the workshop should function as aforum for the exchange of information among Japan, South
Korea and China regarding the standardization of MEMS
devices and their fields of application.
The 4th Japan-Korea-China MEMS Standardization Workshop
will be held in 2008, with Japan once again serving as host.

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