Publikationsserver der RWTH Aachen University
Dynamik der Schichtabscheidung von Keramiken mit KrF-Excimer-Laserstrahlung
Abstract
dc:descriptionThe dynamic during pulsed laser deposition of Al2O3, BaTiO3 and ZrO2 is investigated. The expansion of the laser induced plasma is analytically described as a function of the processing variables and material parameters, considering elastic or inelastic collisions between the ablated particles and the ambient gas. The dynamics of the plasma expansion is experimentally investigated using time and spatially resolved quadrupole mass spectrometry and optical absorption and emission spectroscopy. The predictions of the inelastic collision model approved by the experimental investigations. The density of alumina and zirconia thin films is varied between 30-50% of the bulk density (Ekin<10 eV) and 90-100% of the bulk density at Ekin=20-50 eV. At Ekin>50 eV dense absorbing films are deposited. Structure, texture and orientation of BaTiO3 thin films are governed by the deposition temperature and the kinetic energy of the film forming particles. Using high kinetic energies >50 eV c-axis oriented films are deposited on Pt/Ti/Si(100) substrates while at <20 eV [111] textured films with a high dielectric constant of epsilon_r=1200-1400 (TS=550°C) and epsilon_r=1400-2200 (TS=600°C) are produced. Using in-situ laser annealing during PLD crystalline BaTiO3 films are achieved at low substrate temperatures epsilon_r=300 at TS=360°C and epsilon_r=800-1200 at TS=420-440°C, exploiting the non stationary heating of the growing surface by the pulsed laser radiation without disturbing the substrate beneath comparably.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2001
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Gottmann, Jens
- Contributors dc:contributor
-
- Poprawe, Reinhart
Subjects
dc:subject × 5Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- ger