TiSi2 thin films were prepared by dc magnetronsputtering using a composite TiSix target in the substratetemperature range of 150-550℃. The as-sputtered TiSi2 films atlow temperatures (<250℃) have an amorphous structure with aresistivity of ~250μΩcm, whereas those deposited over 450℃have C49 TiSi2 phase with (060) and (131) orientations. The C54TiSi2 phase having random orientations of (311) and (040) isattained after rapid thermal annealing (RTA) at 750℃ whendeposited at a low temperature regime. The C54 TiSi2 filmsprepared at 450℃ exhibited a preferred orientation of (040)after RTA over 650℃. The sheet resistance (Rs) of patternedTiSi2/polycrystalline silicon structure is as low as ~3Ω□,regardless of substrate temperature, for patterned lines 0.18μmwide after furnace annealing of 800℃ for 60 min. We found theRs dependency of C54 TiSi2 lines on the crystal orientation afterfurnace annealing of 850℃ for 30 min: the structure of C54TiSi2 (040) orientation is more susceptible than that of randomlyoriented C54 TiSi2 (311) and (040) in terms of thermal stability.
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