Preparation And Properties Of B-Ti Composite Reactive Bridge Films

In this paper, three kinds of B-Ti multilayers were successfully deposited on the Silicon substrate by means of RF-magnetron sputtering process. The effects of sputtering power and sputtering pressure on the deposition rate and the quality of films were investigated. The morphology, composition and structure of the thin films were characterized by FE-SEM, AFM, EDS, XPS and XRD. The results showed that the deposition rate of B film increased first with the increasing sputtering power, then increased slowly after the power of150W, on the other hand, when the sputtering pressure was0.3Pa,the deposition rate of B film was the best. Ti film showed well-proportioned grain at the pressure of0.6Pa, and it also appeared smooth and tight with the power at150W. FE-SEM images of morphology showed that when the sputtering power was150W with pressure0.3Pa, the B film was uniformly compact, and when the sputtering power was150W with pressure0.6Pa, the surface of Ti film was smooth with uniform grain; so the best condition for B film was0.3Pa,150W,1.38nm·min-1; the optimum condition for Ti film was0.6Pa,150W,6nm·min-1. FE-SEM and AFM images of morphology showed that the different B-Ti multilayers displayed uniformly compact grain and clear layers which combined hardly. The EDS and XPS showed the elements of the films were unitary with little impurity. XRD patterns revealed that the B film deposited was weak-crystalline by means of some crystalline B2O3; the Ti film and B-Ti multilayers deposited were amorphous.Differential scanning calorimetry test displayed that the B-Ti multilayers had a reaction exothermic peak at600℃to800℃, and the reaction heat was about1300J/g. The activation energies of three kinds of B-Ti multilayers were calculated respectively:E1T=50.885KJ/mol, E2T=41.568KJ/mol, E4T=30.74KJ/mol. The results of electrical explosion revealed that the composite bridge films were implemented thoroughly when the triggering voltage kept at120V, and sparkles which emerged by the explosion were last about200μs-400μs, and spread to a distance of several millimeters or more. Diagnostication of temperature manifested that the temperature of the explosion of the B-Ti multilayers came to6500K-7500K, and the most one even at9000K.