When the primary beam consists of accelerated electrons, the probe is termed an electron microprobe, when the primary beam consists of accelerated ions, the term Ion Microprobe is used. The term microprobe may also be applied to optical analytical techniques, when the instrument is set up to analyse micro samples or micro areas of larger specimens. Such techniques include micro Raman spectroscopy, micro infrared spectroscopy and micro LIBS. All of these techniques involve modified optical microscopes to locate the area to be analysed, direct the probe beam and collect the analytical signal.
Scientists use this beam of charged particles to determine the elemental composition of solid materials (minerals, glasses, metals). The chemical composition of the target can be found from the elemental data extracted through emitted X-rays (in the case where the primary beam consists of charged electrons) or measurement of an emitted secondary beam of material sputtered from the target (in the case where the primary beam consists of charged ions).
When the ion energy is in the range of a few tens of keV (kilo-electron-volt) these microprobes are usually called FIB (Focussed Ion Beam). An FIB makes a small portion of the material into a plasma; the analysis is done by the same basic techniques as the ones used in mass spectrometry.
When the ion energy is higher, hundreds of keV to a few MeV (mega-electron-volt) they are called Nuclear Microprobes. Nuclear microprobes are extremely powerful tools that utilize ion beam analysis techniques as microscopies with spot sizes in the micro-/nanometre range. These instruments are applied to solve scientific problems in a diverse range of fields, from microelectronics to biomedicine. In addition to the development of new ways to exploit these probes as analytical tools (this application area of the nuclear microprobes is called nuclear microscopy), strong progress has been made in the area of materials modification recently (most of which can be described as PBW, Proton Beam Writing).
Another use for microprobes is the production of micro and nano sized devices, as in MEMS and NEMS. The advantage that microprobes have over other lithography processes is that a microprobe beam can be scanned or directed over any area of the sample. This scanning of the microprobe beam can be imagined to be like using a very fine tipped pencil to draw your design on a paper or in a drawing program. Traditional lithography processes use photons which cannot be scanned and therefore masks are needed to selectively expose your sample to radiation. It is the radiation that causes changes in the sample, which in turn allows scientists and engineers to develop tiny devices such as microprocessors, accelerometers (like in most car safety systems), etc.
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Look at other dictionaries:
microprobe — See electron microprobe … Dictionary of molecular biology
microprobe — mikrozondas statusas T sritis radioelektronika atitikmenys: angl. microprobe vok. Mikrosonde, f rus. микрозонд, m pranc. microsonde, f … Radioelektronikos terminų žodynas
microprobe — ˈmīkrəˌˌ noun Etymology: micr + probe (I) : a device for microanalysis that operates by exciting radiation in a minute area or volume of material so that the composition may be determined from the emission spectrum * * * microprobe, process see… … Useful english dictionary
microprobe — noun Date: 1944 a device for microanalysis that operates by exciting radiation in a minute area of material so that the composition may be determined from the emission spectrum … New Collegiate Dictionary
microprobe — /muy kreuh prohb /, n. 1. Chem., Spectroscopy. a device used to excite radiation by a material in order to determine chemical or elemental composition from the emission spectrum produced. 2. Surg. a miniature probe for use in microsurgery. [1955… … Universalium
microprobe — noun an instrument used to determine the chemical composition at a point on a solid surface, such as that of a mineral; analyzes the X rays emitted when a beam of electrons are focused on the sample … Wiktionary
microprobe — mi·cro·probe .prōb n a device for microanalysis that operates by exciting radiation in a minute area or volume of material so that the composition may be determined from the emission spectrum * * * mi·cro·probe (miґkro prōb″) a minute… … Medical dictionary
microprobe — maÉªkrÉ™ÊŠprÉ™ÊŠb n. tiny instrument which beams electrons onto a surface in order to stimulate the emission of X rays that can be analyzed to determine the chemical composition of a material (Spectroscopy) … English contemporary dictionary
microprobe — noun an instrument in which a narrow beam of electrons is focused on to a sample and the resulting fluorescence is analysed to yield chemical information … English new terms dictionary
microprobe — mi·cro·probe … English syllables