A KINETIC-STUDY OF THE C49 TO C54 TISI2 CONVERSION USING ELECTRICAL-RESISTIVITY MEASUREMENTS ON SINGLE NARROW LINES

We describe a simple quasi-in situ resistivity technique and its appli cation to the study of C49 to C54 TiSi2 conversion in narrow (0.1-1.0 mu m) lines. This technique allowed comparison of both aggregate conve rsion versus time at temperature behavior and individual-line conversi on versus time behavior for silicide lines of different linewidths. As linewidth decreased, the aggregate conversion versus time at temperat ure behavior slowed, and the conversion behaviors of individual lines having the same linewidth became more variable. Both of these observat ions are consistent with a nucleation-site-density controlled reaction under conditions of low nucleation site density. Correlations were al so found between individual line behaviors and resistance to agglomera tion; resistance to agglomeration (for 0.35-1.0 mu m lines already in the C54 phase) was highest for lines which had ''prompt'' conversion b ehaviors (as measured by the sheet resistance drop during the first mi nute of the conversion anneal). Additional data concerning the sensiti vity of the initial sheet resistances to formation anneal conditions a nd linewidth is also briefly discussed. (C) 1995 American Institute of Physics.