The miniaturization is a process for the reduction of structures while maintaining the function and possibly also of form.
In technology , this means the constant downsizing of different types of components of technical devices. It has been a target of many developments in science and technology for about three decades . The most important driving factors are requests for increased performance and speed, as well as for a reduction in mass and energy consumption .
In microelectronics , this trend has led to Moore's law being formulated : in chip production, the number of transistors doubles every two years. This increases the complexity of the components and the development costs on the one hand , and the performance and the clock frequency on the other . Constantly growing know-how is required to avoid the increase in interference, for example in signal transmissions . This is why the corresponding methods are among the key technologies and are promoted in many countries through their own research focuses.
Triggered by the development of refined manufacturing methods in electrical engineering , electronics and precision mechanics , miniaturization has, among other things, recorded the following development:
In industry and research, miniaturization has enabled the development of new technologies in recent decades. This development is particularly noticeable in electronics . Both passive electronic components such as resistors and capacitors and active components such as transistors and diodes have been miniaturized more and more in the past. The miniaturization of integrated circuits has a particularly strong influence on electronics development . By reducing the size of the individual transistors in such circuits, it is possible to accommodate more functionality on the same chip area, which leads to a higher packing density and also to lower costs. In addition, the smaller structures achieve shorter switching times for the transistors. This leads, for example, to a noticeable increase in the computing power of microprocessors or an increase in storage capacity. The latter developed in computers from a few tens of thousands of bytes in the desktop computers of the 1970s, through the 16 to 64 kilobytes of the first IBM PC, to many gigabytes of memory in today's computers. The miniaturization of integrated circuits also made new applications and mass products possible, such as PCs , multifunctional mobile phones (cell phones) and other high-frequency technology applications .
Progressive miniaturization is not only taking place in electronics. In fine mechanical processing technology, the accuracy has been increased from a few micrometers (1 µm = 0.001 mm) to less than 0.1 µm, while many work processes are accelerated by robotics . But already in the 1930s there were successful steps in this direction, of which the very compact, innovative travel theodolite DKM1 from Kern-Aarau is one of many examples.
In optics, on the other hand, the lasers could be made much smaller and lenses or mirrors manufactured with greater precision, which has led to the development of CD technology, for example . The performance of today's large astronomical telescopes , which has increased many times over , can also be traced back to highly refined processing methods and the pixel reduction of the CCD sensors .
Establishment of new fields
The basis of many of the developments mentioned was and is the production of small circuits and printed circuit boards (today e.g. wafer technology , dual in-line packages ) and the connection of many components and functions to standardized chips .
This new sub-area of electronics primarily combines miniaturization with functional integration in circuits.
Integrated Circuits (engl. Integrated circuit , IC) combine many transistors, capacitors, coils, and resistors on a single small wafer of layered semiconductor (usually silicon and dopant ). The conductor tracks are produced photolithographically . The miniaturization of the individual components makes it possible for the components of the circuit - and thus the ICs - to be made ever smaller. While a computer used to fill several rooms, today there are ICs of a few mm² in size with several million transistors.
Microelectronics is based on special manufacturing methods, including semiconductor technology and photolithography . The constant downsizing of the components requires increasing quality control and manufacturing tolerances . Currently z. B. those of miniature resistors (20 Ω to a few kΩ) at 10–20%. In the future, it should be pressed to 5% for 10 Ω to 100 kΩ.
The microsystems technology combines microelectronics , micromechanics and micro-optics to edit structures in the micrometer range. This is to be distinguished from nanotechnology , as it involves a paradigm shift and does not just mean scaling down to the nanometer scale. A concrete function is only achieved here through the scaling. One of their typical products are the print heads of modern bubble jet printers . Their micrometer- fine ink nozzles are heated and sometimes combined with miniature computers . Other common products are e.g. B. the integrated acceleration sensors in airbags . The manufacture of microsurgical instruments, the finest sensors or CCD chips is also part of today's standard.
The design and manufacture of microelectronic circuits also includes the processing of crystalline silicon or other semiconductors, as well as special plastics such as. B. the LIGA (manufacturing process) .
Many countries promote microsystem technology through their own priority programs for research projects . The one from the German Federal Ministry of Education and Research has existed since 1990; Meanwhile, in several EU countries there is also a focus on so-called nanotechnology.
It is not directly related to miniaturization, but to the close connection between mechanics, electronics and computer science. It is offered as a degree at several technical universities and technical colleges .
The development and manufacture of modern products requires engineers to think in an interdisciplinary manner - beyond the boundaries of traditional engineering fields. Typical areas of work include communication electronics (cell phones, satellites), vehicle control technology with ABS and electronic diagnosis , environmental and medical technology . In 1995, the University of Applied Sciences Esslingen established the Mechatronics department at the Göppingen location.
Natural limits to the constant downsizing are given by those sizes that have to do with the function of devices, electronics and human-machine communication .
For example, individual keys on a keyboard must have a certain minimum size in order to ensure comfortable operation. In many cases, such as cell phones , this limit is almost exceeded. Possible solutions are a collapsible or fold-out keyboard (on some notebooks , digital cameras , etc.), the operation of miniaturized keys with a pen and the multiple assignment of keys. Another example of the limits of miniaturization are screens or displays : a screen diagonal of at least 10-12 inches is required for longer work. This leads to extreme strain on the eyes or neck muscles . In the meantime, the trend has partially reversed for notebooks, for example - larger (but flatter) formats are coming back onto the market. For the display of digital cameras , about 5 cm should be the minimum. Some manufacturers have taken miniaturization so far that the rear of the camera is largely taken up by the display, or it has to be folded out.
Another limit can arise due to the size-related properties of some components: lenses with too small a diameter result in too low a resolution of the optical system due to the diffraction of light at the mount. Transmission antennas cannot be built as small as desired for a given frequency, which is particularly true for directional antennas. A natural limit is the approach to the dimension of atomic or molecular processes. For example, transistors cannot be made that have less than one atom.
- ISAS Berlin and Dortmund
- Micro optics and mechanics
- Institute for Materials in Electrical Engineering - Microsystem Technology / RWTH Aachen
- TransMechatronic - The specialist portal on the subject of mechatronics funding measure from the Federal Ministry of Education and Research