Silicon Isotopes Enrichment

J. CODNIA; V. D'ACCURSO; A. N. ALCARAZ; . CODNIA Y M. L .AZCÁRATE

Bariloche

Workshop; 13th Workshop on Separation Phenomena in Liquids and Gases SPLG 2015; 2015

Comisión Nacional de Energía Atómica - CNEA

The use of different silicon isotopes has aroused interest in the semiconductor industry since it would improve the optical and electronic properties as well as the thermal conduction of the electronic devices. Laser isotope separation based on the Infrared Multiple-Photon Dissociation (IRMPD) is a promising method of enrichment due to its high selectivity. In this work SiF4 has been used as precursor molecule for silicon isotopes enrichment by IRMPD in a molecular jet. The experiments were performed in a facility consisting of a high vacuum reaction chamber with several windows for laser radiation transmission, a pulsed valve for sample inlet and a time-of-flight mass spectrometer as detection system. The IRMPD was carried out with different lines of the 9.4 μm emission band of a TEA CO2 laser and the multiphoton ionization of the fragments generated, with the 4th harmonic of a Nd:YAG laser (266 nm). A delay unit programmed by a PC controlled the delay times between the sample injection, the dissociation and ionization pulses and the detector signal acquisition. The influence of the laser fluence and wavelength as well as of the delay times between the sample injection, the dissociation and ionization pulses and the detector signal acquisition on the enrichment factors of the different isotopes has been studied.