Thin-film technology
Heraeus Sensor Technology offers a comprehensive selection of sensor elements, microheaters and customised sensors. Starting with SMD chips, the PCB and DBS sensors through to the complex multilayer platform chips.
Technological expertise combined with decades of experience enable Heraeus
Sensor Technology to now achieve Pt structures down to 3 µm with the
photolithographic process. As a comparison: A human hair has a diameter
of
50-100 µm!
Pt temperature sensors
Pt temperature sensors in thin-film technology can also be described as a two-dimensional, microscopic variation of the traditional wire wound type. The wire length and diameter are replaced by a very fine meander structure on a substrate. The manufacturing process is largely automated and thus incorporates the latest technologies, such as is found, for example, in silicon chip production.
Pt microheater (basic flowmeter)
The platinum microheater is designed for applications in the automotive industry, e. g. in air flow meters, for low flow applications in HVAC or for medical analytical equipment. Features include very fast response times, excellent long term stability and very high operating temperature capability.
Pt platform chips
The sensor platform is designed for the mounting of heated sensors. Using heat and temperature measuring resistance, the sensor can, with appropriate control, be kept at a constant temperature or a set temperature cycle can be maintained. Platinum thin-film structures for the heat and temperature measuring resistance are applied to a ceramic substrate and covered with an insulating glass layer. Located on the glass layer is a gold electrode in thick-film technology, onto which a measuring component can be bonded or applied with a thick or thin-film technology. The size of the electrodes allow for the application of the most varied of sensitive layers or the application of Si-Chips. Rectangular wires are used as leads, which allow for lead lengths of up to 170 millimetres. The rectangular wire design offers stability which cannot be achieved with a round cross-section wire.
Note: Platform sensors are custom designed parts made to customer specifications.
General information
In the first production stage, precisely doped platinum, is vapour-deposited
under vacuum onto an Al2O3 substrate. The next step is the photolithographic
transfer of the extremely fine meander structure or electrode structure onto
the blank platinum substrate under clean-room conditions (up to Class 1000).
After thorough etching away of the excess platinum, the finished sensor element
is produced into various versions.
