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Die Erschließung neuer Anwendungsfelder und der Drang zur Größenreduktion von hoch stabilen Druckmesssystemen macht die Erweiterung der Einsatztemperaturbereiche der MEMS Primärsensoren nötig. Es wurden daher piezoresistive Drucksensorsysteme für einen deutlich erweiterten Temperaturbereich entwickelt. Die Leckströme der Sensoren konnten im Bereich bis 300°C um 5 Größenordnungen gesenkt werden. Der Einfluss von allseitigen statischen Drücken konnte unter Anderem durch die Anwendung des Niedertemperatur-Silizium-Direktbondens im Mittel auf Werte kleiner 0,007%FS/100bar gesenkt werden. Die entwickelten piezoresistiven Sensoren auf Siliziumbasis zeichnen sich durch eine hohe Montagespannungsresistenz aus. Die Nullpunktabweichungen nach dem zero-und first-level Packaging betragen weniger als 0,01%FS/24h bei Temperaturen von über 200°C.

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Fast silicon detectors are crucial for a lot of applications, [1] e.g., the experiments at large hadron collider (LHC) at CERN to obtain timeresolved trajectories of particles. A concept to realize such fast silicon detectors are the low-gain avalanche detectors (LGAD). They combine the advantages of normal n-i-p-diodes such as a low noise with a large signal of avalanche multiplication diodes. [2] LGADs operate with a gain of about 10. The avalanche multiplication region is usually obtained by deep boron doped layers. [3] Nevertheless, these LGADs have a drawback if they are irradiated. The gain layer "disappears" after irradiation as a consequence of a deactivation of the gain layer doping species, which is usually boron. [4,5] This means that, e.g., boron, loses after irradiation its properties as an acceptor to provide a negative space charge.In this contribution, the focus is first on LGAD device manufacturing at CiS. Afterward, an experiment is described and discussed, which investigates the acceptor removal phenomenon for the three acceptors boron, gallium, and indium in silicon. Therefore, boron, gallium, and indium were implanted into silicon. Additionally, coimplantation of carbon, oxygen, nitrogen, and fluorine was made. It was found in the literature that for carbon co-implantation the acceptor removal effect can be reduced. [6] Therefore, this study investigates different co-implantation species if they have an impact on the acceptor removal phenomenon. The samples underwent an activation anneal and were then investigated by 4-point-probe (4pp), low temperature photoluminescence spectroscopy (LTPL) and secondary ion mass spectrometry (SIMS) before and after irradiation with electrons and protons.

Abstract. The exploitation of new application fields and the drive to size reduction even in highly stable pressure sensing systems makes the extension of the operating temperature range of the microelectromechanical sensors (MEMS) essential. For this reason a silicon-based pressure sensor with an application temperature ranging up to 300 • C and the associated manufacturing technology was developed. With special design and manufacturing approaches mounting stress-insensitive sensors with high linearity, excellent offset stability, low hysteresis and low sensitivity changes over the entire temperature range were developed. At the moment, the sensors are tested till 300 • C at wafer level and between 135 and 210 • C as a first-level package.