Nanotech 2002 Vol. 2
Nanotech 2002 Vol. 2
Technical Proceedings of the 2002 International Conference on Computational Nanoscience and Nanotechnology

Process Modeling Chapter 14

Numerical Investigations of Laser Induced Crystallization and Stress Development in Phase Change Electroceramic Materials

Authors: N. Pirch, O. Baldus, R. Waser and E.W. Kreutz

Affilation: RWTH Aachen, Germany

Pages: 340 - 343

Keywords: laser crystallization/annealing, thin films, (Ba,Sr)TiO3, stress analysis

Barium-Strontium-Titanate, BST, in the stoichiometry Ba0.7Sr0.3TiO3 to Ba0.5Sr0.5TiO3 is been considered as a promising candidate to enter into the DRAM manufacturing technology. The incompatibility between the temperatures required to crystallize the ferro/para-electric layer into the require Perovskit phase and the thermal budget of underlying active circuitry rules out the application of conventional, quasi-stationary heat treatment of these new materials when integrating into the circuit fabrication process. Thereform, the research focuses on heating amorphous ceramic thin films by laser radiation with pulse durations in the ns regime to induce changes in their structure and electronic properties in the heated region only. To establish intitial operating parameters for the laser-induced crystallization and to study the amorphous to chrystalline phase transformation including stress formation a simulation program is developed. The model includes heat transfer, crystallization and thermal respective phase transformation induced stress analysis.

ISBN: 0-9708275-6-3
Pages: 504