Microelectronics: a macro world
Prof. dr. Lina (P.M.) SarroHoogleraar Microsysteemtechnologie
aan de faculteit Electrotechniek Wiskunde en Informatica
Voorwoord
De studierichting Elektrotechniek in Delft bestaat 100 jaar; een goede reden om daar bij de viering van de 163ste Dies Natalis enige aandacht aan te besteden.
In 1905 werd de Polytechnische School omgezet in de Technische Hogeschool en ontstond de studierichting Elektrotechniek als onderdeel van de Afdeling der Werktuigbouwkunde, Scheepsbouwkunde en Elektrotechniek. In 1919 werd Elektrotechniek een zelfstandige Faculteit [1] die eerst aan de Kanaalweg gehuisvest was en sinds 1969 in het imposante gebouw aan de Mekelweg. In 1998 werden Elektrotechniek, Informatica en Technische Wiskunde in een Faculteit samengevoegd; een combinatie die we bij meer gerenommeerde universiteiten aantreffen.
Sinds kort wordt weer intensief samengewerkt met collega’s van de Faculteit der Werktuigbouwkunde in het kader van de Delft Center Mechatronics and Microsystems (DCMM) en het grote nationale MicroNed programma. De cirkel blijkt dus rond te zijn. Ging het in 1905 om meters en ampères, nu komen nanometers en
microampères aan bod. In de afgelopen 100 jaar heeft de afdeling, later faculteit en nog later sub-faculteit
bijna 5000 excellente elektrotechnisch ingenieurs opgeleid, die een grote bijdrage hebben geleverd en leveren aan de welvaart in Nederland. Bovendien geniet ze een grote nationale en internationale reputatie dank zij haar wetenschappelijk onderzoek. Het Delftse Instituut voor Microelektronica en Submicrontechnologie (DIMES) [2] heeft daaraan ongetwijfeld een groot aandeel in gehad. Ik ben er trots op in dit fantastische instituut mijn bijdrage op het deelgebied van de Microsysteemtechnologie te mogen leveren.
Als gevolg van de vele organisatorische en programmatische veranderingen, maar vooral door de wetenschappelijke en maatschappelijke ontwikkelingen, is het onderwijs en onderzoek bij Elektrotechniek ingrijpend gewijzigd. Bij de Afdeling Microelektronica wordt veel geïnvesteerd in de opleiding van de "nieuwe"
elektrotechnisch ingenieur, die in staat moet zijn in een multidisciplinaire omgeving te opereren, uitstekend te kunnen samenwerken met anderen en oog heeft voor de maatschappelijke consequenties van zijn of haar werk.
Microelektronica heeft sinds de uitvinding van de transistor in 1947 en vooral na de uitvinding van de geïntegreerde schakeling in 1961 ons leven op een onvoorstelbare manier veranderd. Nu, in 2005, neemt de invloed van de microelektronica, de meest belangrijke technologie van de "Informatie maatschappij", alleen nog maar toe. In mijn rede "Microelektronica: een Macrowereld" wil ik u laten zien hoe in Delft op de grote technische en maatschappelijke gevolgen van de microelektronica wordt gereageerd en geanticipeerd. Met macrowereld bedoel ik de veelheid van toepassingen van de microelektronica, zoals vanouds in radio en TV, maar ook in de PC, in de auto, in zorg voor ouderen, in medische apparatuur. Deze toepassingen zijn slechts succesvol, indien vanaf de research fase intensief over de vakgrenzen heen wordt samengewerkt in multidisciplinaire teams. Mijn rede kan daarom worden samengevat met de term: "Micro via Multi naar Macro".
Traditiegetrouw wordt de Diesrede in het Nederlands gehouden. Persoonlijk houd ik wel van tradities. Door onze goede reputatie is de huidige samenstelling van onze TU gemeenschap echter dusdanig internationaal dat het me toch passender lijkt, om de rede in het Engels te houden. Bovendien maakt het duidelijk aan alle niet-Nederlandssprekende medewerkers en studenten dat ze er helemaal bij horen. Multidisciplinair betekent nu eenmaal dat we niet alleen maar rekening kunnen houden met ons eigen wereldje….
Introduction
If we look at our daily life we hardly realize how often we deal with microelectronics. If people would fully appreciate the positive impact microelectronics has and can have on our everyday life we would most certainly experience a remarkable increase in student enrolment at our Department.
From the moment we wake up till the time we go to bed we have probably interacted more than 20-30 times with microelectronics in one way or the other. Even as we sleep our interaction with microelectronics continues through regulated central heating, burglar alarms, etc.
Traditionally, electronics is associated with radio, television, measurement equipment and maybe telecommunication. But how many people associate logistics, transportation, medicine and biology with (micro) electronics? Actually nowadays these areas are unthinkable without microelectronics.
Hospitals and health care centers use more and more advanced diagnostic systems for faster, more accurate and less invasive patient examinations. Surgeons are seeing the operating room change in a rather remarkable way, with dissecting tables getting similar to a flight simulator desk. Driving a car is almost like sitting behind a computer; the process industry (from the pharmaceutical to the food sector) is discovering the enormous impact of on-line monitoring on the quality of final products, on the efficiency of the system and on the reduction of waste.
The multidisciplinary character of microelectronics
It is becoming clearer and clearer that microelectronics is a very multidisciplinary field. Integration among and across several disciplines was already necessary in the early days as a combination of material science, physics and engineering was needed to realize the first transistor. When moving to ICs, more engineering and quite some materials science and chemistry were needed, especially for the development of equipment and processing technology. Now going into micro (and nano) systems, i.e. intelligent systems that combine sensors and actuators, mechanical structures and electronics to sense information from the environment and react to it, we see that chemistry and biology are becoming more and more important, as new materials and phenomena play a major role in the development of new microsystems. Moreover, as movable or flexible parts are often essential components of the system, the role of mechanics - or rather micromechanics - is by far larger than it ever was in conventional electronics.
For the development of these highly integrated miniaturised products, in addition to integration among basic disciplines, a very strong interdisciplinary cooperation is needed between the designers and manufacturers of the electronic circuitry, the software developers and the specialists for the sensors, actuators, displays, and last, but by far not least, the product specialists, who define the requirements of the applications. Although the broad range of expertise and know-how this field requires might make the path to problem solving and product development more difficult, I consider it as enrichment in the engineering world.
Multidisciplinary in (disciplines) and out (application areas)
The impact Microsystems technology is having is far larger than many are aware of. By increasing functionality on a chip (i.e. by adding optical, thermal, chemical and mechanical functions to an electronic circuit) the range and potential of applications have grown exponentially. On the other hand, the difficulties have multiplied as well because of the strong multidisciplinary character of the field required, both “in and out”. In fact microelectronics is entering many industrial sectors that are also becoming increasingly multidisciplinary environments, such as biotechnology, health care and telecommunication.
The large variety of application areas calls for a new type of electronic engineer who is ready to interact with and operate in quite different worlds.
All this underlines the need for a large R&D effort, from basic science and long-term studies into future and emerging technologies to product development, system design and implementation.
A different meaning of miniaturization
Miniaturization is a key factor in microelectronics and is even more crucial in Microsystems Technology. However, the miniaturization associated with
Microsystems has a different motivation than that behind the strong development microelectronics has experienced and continues to experience.
It was back in 1965, just four years after the first integrated circuits were introduced, that Gordon Moore, co-founder of Intel, made his famous observation that the number of transistors on a given area of a semiconductor chip will double every year – a rough measure also of the increase in computer processing power to be expected. Moore revised his law in 1975 – increasing the period of doubling to 1.5-2 years, which, in practice, still applies today [3]. The press called this statement ‘Moore's Law’, and the term is used to indicate the pace of development of the entire microelectronic world.
Moore’s law [3]
In Microsystems, miniaturization is not primarily aimed at reduction of lateral device dimensions so that smaller and faster transistors can be integrated but rather, and even with greater necessity as physical limits are approaching, a means to increase functionality, to increase intelligence, while reducing the space used. So it is no longer the absolute number of transistors per chip area, but rather the functionality level per chip area that counts. Consequently, we can state that the equivalent of Moore’s law for Microsystems is really More functions on a chip instead of More
It is becoming increasingly evident that multi-functionality will be the key to the future. This increase in functionality requires quite some creative thinking, a broad and multidisciplinary knowledge, and an intense cooperation among scientists, engineers and administrators within an organization, and even among organizations and across borders
Thus a more integral approach must be taken as miniaturization will expand rather than reduce the number and variety of functions: by employing miniaturization, more functions, other functions, new functions are possible. Many of us are familiar with what Richard Feynman wisely said about half a century ago: “There is plenty of room at the bottom” [4]. Some of us are familiar with a statement my colleague Lis Nanver made in her inaugural speech two years ago “There is a lot more room at the top”[5]. Well I would expand on that by saying that there is plenty of room at the sides as well.
Three-dimensional microstructuring (or micromachining) of either the silicon wafer and/or of the several layers present in and on the top of the wafer plays a very important role in this pursuit of functionality increase. A large variety of components and systems are realized starting from a planar two-dimensional technology, i.e. the IC technology, to enter the very three-dimensional microsystems.
My fascination for 3D is known to my close collaborators and colleagues all over the world as my research efforts are focussed on ways to literally, figuratively and maybe even socially add a third dimension to electronics. I feel privileged to be involved in such an exciting and rewarding field of great industrial, economic and social relevance.
Microsystems Technology @ DIMES – Delft University of Technology
Impact on society
The impact that developments in microelectronics and microsystems in particular have had and will continue to have on society is huge. In addition to the remarkable improvement of the quality of life, the effect on the economy and the environment through their impact on industrial and consumer products are significant as well.
The impact of Microsystems Technology on society
However, the future generation of microsystems must satisfy quite challenging demands. These systems have to be capable of self-regulation and wireless communication, should be compact in size and operate at low power, often in severe environments.
An integrated autonomous microsystem needs to contain several basic functional modules to interact with its environment. It should be able to sense the perturbation in an environment (hearing or sight,..), as well as to actuate perturbation to the environment for response (motion). It also needs to communicate with other microsystems and with a central point to establish collective and coordinated functions.
Many of the operations involve computing and control for complex information processing. Finally, the autonomous microsystems must contain a power generation/conversion unit. These functions of the autonomous microsystems can be potentially realized by integrating memory/microprocessors with 3D microstructuring in a power-efficient manner (system-on-a-chip). In particular, attention should be paid to novel concepts and principles for power generation at the micro scale in order to enable stand-alone, perhaps embedded, microsensors and microactuators. To provide sufficient power for true autonomy in these systems alternatives to existing batteries must be explored.
While researchers worldwide address the many issues related to the above-mentioned aspects of microsystems, promising results have turned into tangible products. While the rising presence of electronics in the automotive industry or telecommunication industry might be somewhat expected, even more impressive are the impact these developments are having in other areas, such as biology and medicine.
I can sense, think, decide, communicate… Power generation Electronics Sensors Actuators BASE STATION Passives
Integrated autonomous microsystems capable of wireless communication [6]
In fact, as microsystem technology reaches the biomedical field, complex, implantable, tiny devices are emerging whose goal is improved healthcare. Some of these miniature instruments used for biomedical applications are appearing as medical devices as well as playing a role in drug delivery. New drugs need a degree of intelligence to get where they must go and to arrive on time and that’s where semiconductors come in. For example, MicroCHIPS, Inc., a US based company, uses (implantable) silicon microchips containing tiny drug reservoirs that can be opened on demand using pre-programmed microprocessors, remote control, or biosensors [7]. A chip contains up to hundreds or thousands of micro-reservoirs, each of which can be filled with any combination of drugs, reagents, or other chemicals.
Advantages of these microchips include small size, low power consumption, and the ability to store and release multiple drugs or chemicals from a single device at an exact location determined in advance. Products currently in development include external and implantable microchips for the delivery of proteins, hormones, pain medications, and other pharmaceutical compounds.
Advanced pacemakers and defibrillators to be implanted in a continuously increasing number of people with hart conditions, and ultrasonic microtransducers that are to
be placed on an intravascular ultrasound (IVUS) catheter to detect plaque in coronary arteries, are other examples that well illustrate the economic as well as social impact that developments in this field have and can have [8].
Delft University has been one of the first to acknowledge the importance of miniaturization and intelligence for (bio) chemical assays [that are used for quality management in the biotechnology and food industry, medical diagnostics, drug development, environmental monitoring and high-throughput biochemical screening] and has made major contributions to the field. In fact, a rather successful multidisciplinary (DIOC-IMDS) project [9], recently completed, has shown how the combination of several disciplines and groups stimulated by the needs of national and international industry has resulted in the design and realization of an intelligent analytical system that measures many different molecular analytes simultaneously using specific molecular interactions on the surface of specially constructed microchips. Besides allowing a large number of different analyses simultaneously in a very short time, the system uses only extremely small amounts of reagents and samples.
Examples o integrated microsystems for biochemical analysis: array of nanoliter wells for ATP bioluminescence analysis (left); PCR chip for DNA multiplication
(right) [10] f
Nowadays the enormous demand for wireless communications and information services is the main driver for research in our field. The necessity for low-cost and high-efficiency system implementations for these communications capabilities has generated an explosion in the development of all the elements needed in the communication chain, from materials & basic phenomena all the way to system architecture.
The research on wireless microsystems is necessary not only to guarantee that they can operate just about anywhere, like in the human body or in inaccessible, dangerous places, but also for remote and/or continuous monitoring at a fast pace and at acceptable costs. This is well incorporated in the intelligent wireless environment vision, a vision that has been embraced by our department. Many aspects related to the wireless character of components and systems are indeed being studied. Moreover, while further miniaturization with the aim of increasing functionality is pursued, system integration and lowering power consumption are addressed at all times.
Internationalization is a fact.
Microelectronics in general and Microsystems in particular have secured Delft a leading international position. Since the start of the international MSc in ME in 2000 the number of applications has steadily increased. Not only more foreign students are coming to Delft, but the number of Dutch students has increased as well. Apparently the international character of the programme, including the use of English as the teaching language, has not been experienced as a deterrent by Dutch students, as some might have feared beforehand, but rather as an enrichment of their education, both technically and socially. This learning process could in fact be very useful to properly function in the global world we operate in nowadays.
The internationalization extends to the Graduate education and research, where the percentage of non Dutch PhD students and junior researchers grows at an even larger pace.
The fact that the Department of Microelectronics & Computer Science, strengthened by the presence of the DIMES Research School and the ICT (Information & Communication Technology) Delft Research Center ICT [11], covers the entire spectrum from concept to realization, from material study to systems, hardware and software, fundamental phenomena coupled with demonstrators makes it extremely appealing to international PhD students as well as to companies worldwide. I do believe we have found a good balance between the advanced, industry-like technology environment -- which is important to determine and compare our technological achievements with those of the major players in the world as well as to guarantee the potential of technology transfer to an industrial environment -- and the flexibility and multi-sided possibilities necessary to investigate and implement innovative concepts and advanced functions.
The increase of students in the Microelectronics Master of Science program
Both in terms of education and research this is our strength, this makes us special. We need to maintain the high standards of our research, we need to improve and adapt our education program to the pace of the social and industrial changes, to continue to cooperate and interact within the University, within The Netherlands, with the other European Academic and Industrial laboratories, with the entire world so that we can continue to offer great potential and exercise strong attraction on top students and scientists.
According to a recently published report [12] drawn up by top-level executives from European industries and research organizations, huge investments are required for Europe to remain at the forefront of global developments and to stay ahead of strong international competition. Among the key recommendations we find: Create a technology platform to strengthen collaborative research and develop an education system delivering a skilled multidisciplinary workforce. Once again also for the future we find the two crucial keywords: collaboration & multidisciplinarity. These are words that are quite meaningful to the Delft University, words that in the field of microelectronics and even more specifically in microsystems we are quite familiar with.
In 2002 funding for microelectronics in the Asia-Pacific region reached 62% of total capital spending, whereas it amounted only to 8% in Europe. This means that we can do our job to train the right type of workforce by modifying our B.Sc and M.Sc. programs, intensifying our cooperation with fellow institutions and industries
worldwide, however, if we want to maintain and improve a relevant position in this important area, we cannot do it alone. We do need the industry and government to do their part as well.
A final word
The immense contribution that ICs have made to society over the last four decades is indisputable. A few months ago in a survey [13] among leading thinkers from the science and the engineering world were asked three main questions:
What has been the most important technology of the last 40 years? What technology has evolved in a way that surprised you?
What technology will have the biggest impact in the coming decade?
The answer to the first question was clearly the transistors (and as a consequence the computer and the internet)
For the surprising development the answer was not so much a specific technology, but more the pace at which the change, the development, the impact took place; i.e., the speed at which applications evolved.
Wireless communication and computation, distributed sensing and embedded systems were the technologies expected to have the largest impact in the coming decade.
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Here in Delft we certainly agree with the answers to the first two questions and the areas indicated as having the most relevance for the next decade are areas wherein the Department of Microelectronics & Computer Science & DIMES are actively involved, both at teaching and research level, participating in many international programs and even being frontrunners for a few specific areas.
So we can rightly say that microelectronics uses miniaturization to create, interact and address a macro world; a macro world because of the variety of applications area has entered, a macro world because of the large and positive impact on everybody’s life, a macro world because of the global character of its research and development, a macro world because of the specific characteristic of being a truly multidisciplinary field as it brings together science, technology, economics and society.
References
[1] J. Davidse, Spanning – Geschiedenis van de Delftse Opleiding tot Elektrotechnisch Ingenieur, ISBN 90-407-1794-X/CIP
[2] http://www.dimes.tudelft.nl
[3] http://www.intel.com/research/silicon/mooreslaw.htm
[4] R. Feynman, The e's Plenty of Room at the Bottom, Caltech's Engineering and Science, February 1960 (http://www.zyvex.com/nanotech/feynman.html)
[5] L.K.Nanver, Respect for Quantity, Inaugural speech, Delft university of Technology, 23 April 2003.
[6] P.M.Sarro, M3: the third dimension of silicon, in Enabling Technologies for MEMS
and Nanodevices, H.Balteset al Eds, Wiley Publ., 2004. ISBN: 3-527-30746-X
[7] http://www.mchips.com/ [8] IEEE Spectrum, October 2004
[9] http://www.ph.tn.tudelft.nl/Projects/DIOC/Progress/DIOC.Progress.html [10] V.P. Iordanov, Nano-liter sensor arrays for biochemical analysis, PhD Thesis, Delft University of Technology, December 2004, ISBN 90-9018993-9
[11] http://www.ict.tudelft.nl/
[12] Vision 2020: Nanoelectronics at the centre of change, June 2004, ISBN 92-894-7804-7
[13] IEEE Spectrum, Nov 2004 Acknowledgements
I am grateful to Tieme Dekker en Michiel van de Zwan for their help with the pictures and the slides.
I would also like to thank many colleagues and students for various forms of support and for making my work so enjoyable.
