Semiconductor devices - Micro-electromechanical devices -- Part 1: Terms and definitions

This part of IEC 62047 defines terms for micro-electromechanical devices including the process of production of such devices.

Halbleiterbauelemente - Bauteile der Mikrosystemtechnik -- Teil 1: Begriffe und Definitionen

Dispositifs à semiconducteurs - Dispositifs microélectromécaniques -- Partie 1: Termes et définitions

This part of EN 62047 defines terms for micro-electromechanical devices including the process of production of such devices.

Polprevodniški elementi - Mikroelektromehanski elementi - 1. del: Izrazi in definicije (IEC 62047-1:2005)

General Information

Status
Withdrawn
Publication Date
31-Dec-2006
Withdrawal Date
07-Mar-2019
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
04-Mar-2019
Due Date
27-Mar-2019
Completion Date
08-Mar-2019

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EUROPEAN STANDARD EN 62047-1 NORME EUROPÉENNE
EUROPÄISCHE NORM June 2006
CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2006 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62047-1:2006 E
ICS 31.080.99
English version
Semiconductor devices - Micro-electromechanical devices
Part 1: Terms and definitions (IEC 62047-1:2005)
Dispositifs à semiconducteurs - Dispositifs microélectromécaniques
Partie 1: Termes et définitions (CEI 62047-1:2005)
Halbleiterbauelemente - Bauteile der Mikrosystemtechnik
Teil 1: Begriffe und Definitionen
(IEC 62047-1:2005)
This European Standard was approved by CENELEC on 2006-06-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.



EN 62047-1:2006
- 2 -
Foreword The text of the International Standard IEC 62047-1:2005, prepared by IEC TC 47, Semiconductor devices, was submitted to the Unique Acceptance Procedure and was approved by CENELEC as EN 62047-1 on 2006-06-01 without any modification. The following dates were fixed: – latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement
(dop)
2007-06-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2009-06-01 __________ Endorsement notice The text of the International Standard IEC 62047-1:2005 was approved by CENELEC as a European Standard without any modification. __________



NORME INTERNATIONALECEIIEC INTERNATIONAL STANDARD 62047-1Première éditionFirst edition2005-09 Dispositifs à semiconducteurs – Dispositifs microélectromécaniques – Partie 1: Termes et définitions
Semiconductor devices – Micro-electromechanical devices – Part 1: Terms and definitions
Pour prix, voir catalogue en vigueur For price, see current catalogue IEC 2005
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Copyright - all rights reserved Aucune partie de cette publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et les microfilms, sans l'accord écrit de l'éditeur. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Electrotechnical Commission,
3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, SwitzerlandTelephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch
Web: www.iec.ch CODE PRIX PRICE CODE T Commission Electrotechnique InternationaleInternational Electrotechnical Commission



62047-1  IEC:2005 – 3 –
CONTENTS FOREWORD.5
1 Scope.9 2 Terms and definitions.9 2.1 General terms.9 2.2 Terms relating to science and engineering.11 2.3 Terms relating to material science.13 2.4 Terms relating to functional element.15 2.5 Terms relating to machining technology.25 2.6 Terms relating to bonding and assembling technology.37 2.7 Terms relating to evaluation technology.41 2.8 Terms relating to application technology.43
Annex A (informative)
Standpoint and criteria in editing this glossary.49



62047-1  IEC:2005 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
SEMICONDUCTOR DEVICES – MICRO-ELECTROMECHANICAL DEVICES –
Part 1: Terms and definitions
FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC 62047-1 has been prepared by IEC technical committee 47: Semiconductor devices. The text of this standard is based on the following documents: FDIS Report on voting 47/1821/FDIS 47/1840/RVD
Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table. This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.



62047-1  IEC:2005 – 7 –
IEC 62047 consists of the following parts, under the general title Semiconductor devices − Micro-electromechanical devices: Part 1: Terms and definitions Part 2: Tensile testing methods of thin film materials (in preparation) Part 3: Thin film standard test piece for tensile testing (in preparation) The committee has decided that the contents of this publication will remain unchanged until the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to the specific publication. At this date, the publication will be
• reconfirmed, • withdrawn, • replaced by a revised edition, or • amended.



62047-1  IEC:2005 – 9 –
SEMICONDUCTOR DEVICES – MICRO-ELECTROMECHANICAL DEVICES –
Part 1: Terms and definitions
1 Scope This part of IEC 62047 defines terms for micro-electromechanical devices including the process of production of such devices. 2 Terms and definitions For the purposes of this document, the following definitions apply. 2.1 General terms 2.1.1
micro-electromechanical device microsized device, in which sensors, actuators, mechanical components and/or electric circuits are integrated 2.1.2
MEMS microsized electromechanical systems, in which sensors, actuators and/or electric circuits are integrated on a chip using a semiconductor process NOTE MEMS is an acronym standing for "micro-electromechanical systems". The term MEMS is mostly used in the United States. In general, this term means technologies to realize microstructures, sensors, and actuators by using silicon process technology, though it is occasionally used in some other meanings. 2.1.3
MST technologies to realize microelectrical, optical and machinery systems and even their components by using micromachining NOTE MST is an acronym standing for microsystem technologies. The term MST is mostly used in Europe. 2.1.4
micromachine miniaturized devices the components of which are several millimeters or smaller in size, or a microsystem that consists of an integration of such devices NOTE The term 'micromachine' has a broad sense from a functional device such as sensor that utilizes the micromachine technology to a completed system. A molecular machine called a nanomachine is also included. Such industrial applications are expected as inspection and repair systems for piping or confined spaces, and micro-factories, which consume less energy. In the medical field, micromachines are expected to replace ordinary surgery by less invasive treatment from the inside of the body. Research and development for the realization of micromachines is divided into two approaches: micro-electromechanical systems (MEMS) using semiconductor manufacturing processes, and miniaturization of the existing machine technologies.



62047-1  IEC:2005 – 11 –
2.1.5
micromachine technology technology relating to micromachines NOTE Micromachine-related technologies are extremely diversified. In the fundamental technology field, micromachine technologies include: design, material, processing, functional element, system control, energy supply, bonding and assembly, electrical circuit, and evaluation as well as micro-science and engineering such as thermodynamics and tribology in a microscale. Micromachine technologies have two aspects: technologies required to realize micromachines, and technologies required to apply such technical seeds to other industrial fields. 2.2 Terms relating to science and engineering 2.2.1
micro-science and engineering science and engineering for the microscopic world of micromachines NOTE When mechanical systems are miniaturized, various physical parameters change. Two cases prevail: 1) these changes can be predicted by extrapolating the changes of the macro-world, and 2) the peculiarity of the microscopic world becomes apparent and extrapolation is not possible. In the latter case, it is necessary to establish new theoretical and empirical equations for the explanation of phenomena in the microscopic world. Moreover, new methods of analyses and syntheses to deal with engineering problems must be developed. Material science, fluid dynamics, thermodynamics, tribology, control engineering, and kinematics can be systematized as micro-sciences and engineering supporting micromechatronics. 2.2.2
scale effect changes of various effects on the objects behaviour or the properties caused by the change of the object's dimension NOTE The volume of an object is proportional to the third power of its dimension, while the surface area is proportional to the second power. As a result, effect of surface force becomes larger than that of the body force in the microscopic world. For example, the dominant force in the motion of microscopic object is not the inertial force but the electrostatic force or viscous force. Material properties of microscopic objects are also affected by the internal material structure and surface, and, as a result, characteristic values are sometimes different from those of bulks. Frictional properties in the microscopic world also differ from that in the macroscopic world. Therefore, those effects must be considered cautiously while designing a micromachine. 2.2.3
mesotribology tribology applying to the intermediate mesoscopic area between the microscopic world and the macroscopic world NOTE Tribology deals with friction and wear in the macroscopic world. On the other hand, two major topics of microtribology research are the investigation of tribology phenomena on an atomic or molecular scale, and the quantification of characteristics in friction or wear. If the macro-characteristics generated on both surfaces undergoing relative motion are traced to where they originate, the minimum unit of the atomic or molecule cluster causing those characteristics is reached. Observation on a finer scale reaches a boundary at which these characteristics disappear. Mesotribology pursues new developments on the micro-macro boundary by bringing together atoms on a subnanometer scale to create a mesoscopic scale and investigating the tribological phenomena on this scale.



62047-1  IEC:2005 – 13 –
2.2.4
microtribology tribology for the microscopic world of micromachines NOTE Tribology deals with friction and wear in the macroscopic world. On the other hand,when the dimensions of components such as those in micromachines become extremely small, surface force and viscous force become dominant instead of gravity and inertial force. According to Coulomb's law of friction, frictional force is proportional to the normal load. In the micromachine environment, because of the reaction between surface forces, a large frictional force occurs that would be inconceivable in an ordinary scale environment. And very small quantity of abrasion that would not become a problem in an ordinary scale environment can fatally damage a micromachine. Microtribology research seeks to reduce frictional forces or to discover conditions that are free of friction, even on an atomic level. In this research, phenomena that occur with friction surfaces or solid surfaces at from angstrom to nanometer resolution are observed, or analysis of interaction on an atomic level is performed. These approaches are expected to be applied in solving problems in tribology for the ordinary scale environment as well as for the micromachine environment. 2.2.5
biomimetics creating functions that imitate the motions or the mechanisms of organisms NOTE In devising microscopic mechanisms suitable for the micromachines, the mechanisms and structures of organisms that have survived severe natural selection may serve as good examples to imitate. One example is the microscopic three-dimensional structures that were modelled after the exoskeletons and elastic coupling systems of insects. In exoskeletons, hard epidermis is coupled with an elastic body, and all movable parts use the deformation of the elastic body to move. The use of elastic deformation would be advantageous in the microscopic world to avoid the friction. Also, the exoskeleton structure equates to a closed link mechanism in kinematics and has the characteristic that some actuator movement can be transmitted to multiple links. 2.2.6
ciliary motion coordinated motion of multiple cilia NOTE Progressive waves are generated by coordinated motion of multiple cilia, which is used to transfer fluid or tiny particles, or are used to propel a microscopic organism itself. An example of the former is the ejection of microscopic waste from human tracheae, and of the latter is the swimming of unicellular organisms, such as paramecium. By imitating these ciliary motions, actuators with many artificial cilia have been fabricated by micromachining. 2.2.7
self-organization organization of a system without any external manipulation or control, where nonequilibrium structure emerges spontaneously due to the collective interactions among a number of simple microscopic objects or phenomena 2.3 Terms relating to material science 2.3.1
shape memory polymer resin that can recover its primary shape after being deformed when it is heated or receives any other stimuli NOTE To have the shape memory property, a resin has to have mixed domains of the bridged or partially crystallized fixed phase and the reversible phase. Memorizing and restoring a shape takes the following steps. The resin is kept above a specific temperature to soften both the fixed and reversible phases. Then, holding the resin in one shape (primary shape), temperature is lowered to freeze the fixed phase while the reversible phase is kept soft, thereby storing memory of the primary shape. Then the resin is deformed to another shape (secondary shape) by external force, and cooled further to freeze the reversible phase and keep the secondary shape. In this state, the secondary shape is retained even if the external force is removed. The stored primary shape is restored if the resin is heated to the temperature at which only the reversible phase softens. Since restoration shape is enabled by softening by heat, the generated force is limited. Some resins recover shape not by heat but by changes in pH, electrical stimuli, or light stimuli. Shape memory resins are made of polyester, polyurethane, styrene butadiene, polynorbornane, transpolyisoprene, and so on.



62047-1  IEC:2005 – 15 –
2.3.2
modification processing technology that modifies physical or chemical properties of the material NOTE Modification processes include local doping by a focused ion beam, laser doping inducing phase transition such as single crystal formation, ion implantation, and ion mixing. 2.4 Terms relating to functional element 2.4.1
actuator mechanical device that converts various types of energies such as electric energy, chemical energy into kinematic energy to perform mechanical work NOTE For a micromachine to perform mechanical work, the microactuator is indispensable as a basic component. Major examples are the electrostatic actuator prepared by silicon process, piezoelectric actuator that utilizes functional materials like lead zirconate titanate, PZT, pneumatic rubber-actuator, and so on. Many other actuators based on various energy conversion principles have been investigated and developed. However, all these actuators deteriorate their energy conversion efficiency as their size is reduced. Therefore, motion mechanisms of organisms such as deformation of protein molecules, flagellar movement of bacteria, and muscle contraction are being utilized to develop special new actuators for micromachines. 2.4.2
microactuator actuator produced by micromachining NOTE For example, micro-electrostatic actuators are actuated by micro-electrostatic field, magnetic microactuators are driven by micromagnetic field, and piezoelectric microactuators depend on microstress field to convey motion and power. 2.4.3
light driven actuator actuator that uses light as control signal or energy source NOTE After the development of photostrictive materials, various light driven actuators have been proposed. These actuators have simple structures and can be driven by wireless. A motor is proposed that utilizes the spin realignment effect, in which a magnetic material absorbs light and the resulting heat changes the direction of magnetization reversibly. Actuators utilizing thermal expansion, and exploiting polymer photochemical reactions, are also studied. 2.4.4
piezoelectric actuator actuator that uses piezoelectric material NOTE Piezoelectric actuators are classified into the single-plate, bimorph, and stacked types, and the popular material is lead zirconate titanate (PZT). The features are: 1) Quick response, 2) Great output force per volume, 3) Ease of miniaturization because of simple structure, 4) Narrow displacement range for easier microdisplacement control, and 5) High effeciency of energy conversion. Piezoelectric actuators are used for the actuators for micromachines, such as ultrasonic motor, microdisplacement stage, fan, pump, and speaker. An applied example is a piezoelectric actuator for traveling mechanism which moves by the resonance vibration of a piezoelectric bimorph, and a micropositioner piezoelectric actuator which amplifies displacements of a stacked piezoelectric device by a lever.



62047-1  IEC:2005 – 17 –
2.4.5
shape memory alloy actuator actuator that uses shape memory alloy NOTE Shape memory alloy actuators are compact, light, and produce large forces. The actuators can be driven repeatedly in a heat cycle or can be controlled arbitrarily by switching the electric current through the actuator itself. Lately, attempts have been made to use the alloys to build a servosystem that has an appropriate feedback mechanism and a cooling system, intended for applications where quick response is not necessary in particular. Application examples under development are microgrippers for cell manipulation, microvalves for regulating very small amounts of flow and active endoscopes for medical use. 2.4.6
sol-gel conversion actuator actuator that uses the transition between the sol (liquid) state and the gel (solid) state NOTE A sol-gel conversion actuator can work in a similar way to living things. For example, if electrodes are put on small particle of sodium polyacrylate gel in electrolytic solution and a voltage is applied, the particle repeatedly changes its shape. They can be connected in series, sealed in a thin pipe and given with multiple legs, to make a microrobot that moves in one direction that looks like a centipede. Another application being conceived is a crawler microrobot that automatically moves through a thin pipe. 2.4.7
electrostatic actuator actuator that uses electrostatic force NOTE Since the electrostatic actuator has a simple structure and its output force per weight is increased as the size is reduced, many researches are ongoing to apply it to the actuator of micromachines. Application examples developed so far on an experimental basis include a wobble motor, a film electrostatic actuator, and so on. 2.4.8
comb drive actuator electrostatic actuator, consisting of a series of parallel fingers, fixed in position, engaged and interleaved with a second, movable set of fingers NOTE Application of an electrostatic charge to the first set attracts the fingers of the second set, such that they become more fully engaged in the interdigit spaces of the first set. Then the static charge is removed and drained, the second set is returned to its home position by micromachined spring tension. 2.4.9
wobble motor variable gap electrostatic motor that generates rolling motion of the rotor on eccentric stator without slip NOTE Wobble motors are also called harmonic electrostatic motors. These motors consist of a rotor, a stator with electrodes for the generation of electrostatic force, and an insulation film on the rotor or stator surface. The rotor rotates in a reverse direction to the revolution. The rotation speed, rotV, is given as ()rotrotstatrevrot/LLLVV−×=. Where, revV is the revolution speed, statL is the stator circumference, and rotL is the rotor circumference. Characteristics of the wobble motor include 1) the ability to easily provide low speed and high torque when the rotor circumference is very close to the stator circumference, 2) no friction and wear problems because of no sliding parts, 3) the ability to use diverse materials, 4) an easily increasable aspect ratio. On the other hand, the revolution of the rotor can cause unnecessary vibration. Production examples include a wobble motor that supports a rotor by a flexible coupling, and a wobble motor fabricated by the IC process and whose rotor rolls at the fulcrum.



62047-1  IEC:2005 – 19 –
2.4.10
microsensor device, produced by micromachining and which is used for measuring the physical or chemical quantity NOTE In micromachines, the first field to be developed and realized is that of the microsensor. Microsensors include mechanical quantity sensors (measuring pressure, acceleration, tactile senses, displacement, etc.), chemical quantity sensors (measuring ions, oxygen, etc.), electrical quantity sensors (measuring magnetism, current, etc.), biosensors, and optical sensors. In many microsensors, the detecting section containing the mechanism is integrated with the electronic circuits. The advantages of microsensors are: 1) less environmental disruption, 2) the ability to measure local states of small areas, 3) integration with circuits, and 4) less operating power. 2.4.11
biosensor sensor that use organic substances in the device, that are intended for measurement of organism related subsystems, or that mimic an organism NOTE A typical biosensor consists of the biologically originated specific material such as an enzyme or an antibody that identifies the object of measurement and the device that measures a physical or chemical quantity change related to the identifying reaction. A semiconductor sensor or any of various types of electrodes (ex. ISFET, micro-oxygen electrode, and fluorescence detection optical sensor) prepared by silicon micromachining tech-nology can be used as this device. Biosensors are used for blood analysis systems, glucose sensors, microrobots, and so on. 2.4.12
integrated microprobe one-piece probe combining a microprobe and a signal processing circuit NOTE The smaller the sensitive part of the sensor, 1) the less interference to the measuring object, 2) the higher the signal-to-noise ratio in the measurement, and 3) the more small-area local data can be obtained. An integrated microprobe is a device consisting of a microprobe prepared by micromachining silicon to an ultra-microscopic needle and incorporating a signal processing circuit. Integrated microprobes made by machining silicon needles to a diameter of from several nanometers to several micrometers and combining them with an impedance conversion circuit, etc., are in actual use as microscopic electrodes for organisms, scanning tunneling microscopes (STMs), and atomic force microscopes (AFMs).
2.4.13
ion sensitive field effect transistor
ISFET semiconductor sensor integrating an ion sensitive electrode with a field effect transistor (FET) NOTE In the ion sensitive electrode section, the membrane voltage changes according to fluctuations of pH or carbon dioxide partial pressure in blood, for example. As the voltage amplifier, the ISFET uses a FET, a transistor controlling the conductance of the current path (channels) formed by the majority carriers using an electrical field perpendicular to the carrier flow. The ISFET is based on silicon micromachining technology integrating a detector and amplifier on a silicon substrate. In addition, an ISFET with mechanical components such as a valve has been developed. The ISFET is used in such fields as medical analysis and environmental instrumentation.



62047-1  IEC:2005 – 21 –
2.4.14
accelerometer transducer that converts an input acceleration to an output (usually electrical) that is proportional to the input acceleration [ISO 2041:1990]1 NOTE This accelerometer, based on silicon micromachining technology, is typically composed of a soft spring and a mass. The accelerometer senses the displacement of the spring caused by the inertia of the accelerated mass, or detects acceleration from the measurement of the force required to cancel this displacement. Among today's silicon-made sensors, accelerometers hold particular promise as a next-generation product. There are many types of accelerometer such as semiconductor strain gauges, capacitance detectors, electromagnetic servosystems, and electrostatic servosystems. In addition, vibration detection-type accelerometers, which detect changes in resonance frequencies, and piezoelectric effect-type accelerometers, which use the piezoelect
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