11253

10344

كارشناسي ارشد

ماده چگال

اصفهان: دانشگاه صنعتي اصفهان، دانشكده فيزيك

1394

يازده، 131ص.: مصور

پرويز كاملي

مهدي رنجبر

حسين احمدوند، اسماعيل عبدالحسيني

1395/02/19

فيزيك

ID10344

E ect of substrate temperature lattice mismat and Ta underlayer on magnetic FePt thin lms prepared by pulsed laser deposition Parisa Mokhtari p mokhtari@ph iut ac ir 9 1 2016 Department of Physics Isfahan University of Te nology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor prof Parviz Kameli p kameli@cc iut ac irAbstract e L1 FePt alloy has been extensively studied and proposed as a promising candidate for ultra high density recording media Due to its large magnetocrystalline anisotropy and very small cryticalgrain size FePt becomese thermally stable at room temperature In this resear we have investigated the e ect of substrate temperature la ice mismat and Ta cap ping layer and underlayer on the structure and magnetic properties of FePt thin lms In all samples the external magnetic eld have been used to improve and control the intensity of Laser plume FePt thin lms were prepared by pulsed laser deposition on Si 100 and Si SiO2 100 sin gle crystal substrates at di erent substrate temperatures of 600 700 and 800 C under ultrahighvacuum 3 3 10 6 T orr e microstructures degree of ordering surface morphology and mag netic properties of FePt thin lms were investigated e results showed that L1 crystal structure wascreated As the temperature increased the growth of grain size was observed e increasing of stressfrom due to the la ice mismat in F eP t Si 100 thin lm leads to ange of surface morphologyfrom Island like mode to continuous mode Also the roughness of surface and coercivity increasedwith increasing la ice mismat and temperature Results indicated that the strain from the lowerla ice mismat improved the ordering of the FePt lms also in this resear we used Ta for capping layer and underlayer in FePt thin lms with quartzsubstrate In this part FePt thin lms were deposited onto quartz substrate at room temperature elayer structure was T a F eP t T a Quartz the samples were then subjected to rapid thermal an Cnealing RT A at temperature of 500 700 and 800 C for 30 min with heating rate of about 60 s Inthese samples e results of Xray di raction pa erns showed that the L1 crystal structure was notcreated e very low coercivity were obtained for these samples Keywords FePt thin lms pulsed laser deposition underlayer La ice mismat

پرويز كاملي

مهدي رنجبر

حسين احمدوند، اسماعيل عبدالحسيني