Regensburg 2019 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
DS: Fachverband Dünne Schichten
DS 14: Poster
DS 14.35: Poster
Dienstag, 2. April 2019, 17:00–20:00, Poster E
The dependence of piezoelectric performance of AlN thin films on Si(111) on post-growth annealing treatment — •Dmytro Solonenko1, Constance Schmidt1, Chris Stoeckel2, Karla Hiller2, and Dietrich R.T. Zahn1 — 1Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany — 2Zentrum für Mikrotechnologie, Chemnitz University of Technology, 09107 Chemnitz, Germany
Aluminum nitride (AlN) is a material well-suited for microelectromechanical systems (MEMS) due its relatively high piezoelectric coefficients as well as high physical and chemical stability. Thin AlN films, used in the production of MEMS, are often fabricated by reactive magnetron sputtering, which, despite its efficiency and low cost, is known to produce films of mediocre quality and thus tolerable piezoelectric performance. The effect of post-growth annealing, which is usually performed to improve the crystallinity of semiconductors, was investigated for sputtered AlN films by X-ray diffraction, Raman and IR spectroscopies, spectroscopic ellipsometry, and atomic force microscopy. The results show that the strain built in the films during the growth starts to effectively relax at around 1000 ∘C, which is related to a dewetting of the AlN crystallites from the silicon substrate surface under formation of O-containing species such as SiO2 and AlON. Up to 800 ∘C, the average grain size enlarges and the film porosity is reduced, which positively affects the piezoelectric coefficient, d33, determined using piezoresponse force microscopy.