P2.2 - Fabrication of high-sensitivity pyroelectric sensors by ion beam etching
- 18. GMA/ITG-Fachtagung Sensoren und Messsysteme 2016
2016-05-10 - 2016-05-11
- P2 Infrarot-Messverfahren
- R. Rückriem, M. Zeuner - scia Systems GmbH, Chemnitz (Germany), R. Köhler - DIAS INFRARED GMBH, Dresden (Germany)
- 551 - 554
Ion beam etching of pyroelectric sensors made of lithium tantalate (LT) is presented in order to get a higher specific detectivity D* compared to standard sensors. We present the etching tool which applies argon ion beam etching in production environment. The etching homogeneity was investigated by a standard silicon oxide etch and a twelve hour silicon etch with photoresist mask. Both show a homogeneity of +/- 0.7 % and a good compliance. Further investigations were done in a twelve hour process regarding the stability of the ion current regulation and ion current density. In the first two hours after process start, the main variation of power and ion current density takes place. Afterwards, the system reached a steady-state. After etching of the LT samples, an analysis of the removed material and emerged etching walls was done. Finally, the important D* was compared between an ion-etched and a non-ion etched pyroelectric sensor.