U.P.B. Sci. Bull., Series B, Vol. 73, Iss. 2, 2011 ISSN 1454-2331 FeSi THIN FILMS DEVELOPED BY PULSED LASER DEPOSITION Cătălin CONSTANTINESCU 1 , Horia GAVRILĂ 2 În lucrare sunt prezentate rezultate asupra unor straturi subţiri din FeSi depuse prin ablaţie laser pe subtrat de siliciu, siliciu acoperit cu platină, cuarţ, ceramică SITAL şi sticlă (tip BK7). A fost studiată influenţa parametrilor de depunere (presiunea în camera de depunere, lungimea de undă, fluenţa laser) asupra structurii şi morfologiei straturilor subţiri: structura suprafeţei şi interfaţa film-substrat, proprietăţile electrice şi magnetice au fost în mod special investigate din această perspectivă. This paper presents some results on FeSi thin films deposited by pulsed laser deposition on silicon, platinum covered silicon, quartz, SITAL ceramic and glass (type BK7) substrates. The influence of the deposition parameters (background pressure, laser wavelength, laser fluence) on the structure and morphology of the thin films was studied: the thin film superficial and thin film-substrate interface characteristics, the electrical and magnetic properties were particularly investigated from this perspective. Keywords: FeSi, thin film, PLD 1. Introduction With all its remarkable properties, when used in AC magnetic devices, the industrial iron (or soft iron) has two major disadvantages: high electrical conductivity and bad magnetization loops (magnetic hysteresis; both leading to important energy losses. To reduce such losses and/or to improve the quality of electrical devices, soft iron must be used in alloys together with other elements; the most important and common of these is silicon (Si). FeSi alloys maintain their magnetic properties up to 33% Si content (expressed as mass percentage, that corresponds to 50% atomic percentage. These types of alloys are used mainly for the construction of electrical machinery, electrical transformers and in power equipment that works at the industrial AC frequency (50 or 60 Hz). Such alloys, used in different forms and composition varieties, represent the best economical combination in terms of production costs and magneto-mechanical properties. 1 PhD student, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor blvd, Magurele RO-077125, Bucharest, Romania, e-mail: catalin.constantinescu@inflpr.ro 2 Prof., Department of Electrical Engineering, University POLITEHNICA of Bucharest, Romania