Page 218 - Sami Franssila Introduction to Microfabrication

Self-aligned Structures 197

19.5 EXERCISES 4. Estimate the final TiSi 2 film thickness for a two-
step nitrogen annealing process given that the initial
1a. How thick a titanium silicide layer will be formed
from a 100 nm thick titanium layer under argon titanium thickness is 50 nm.
annealing?
1b. Where is the surface of TiSi 2 relative to original
silicon surface? REFERENCES AND RELATED READINGS
2. What was the original titanium thickness in Gambino, J.P. & E.G. Colgan: Silicides and ohmic contacts,
Figure 19.5? Mater. Chem. Phy., 52 (1998), 99–146.
3. Analyse the fabrication steps of the dual-silicide
Hou, T.-H. et al: Improvement of junction leakage of nickel
structure shown below. Oxide is grey; silicides
silicided junction by a Ti-capping layer, IEEE EDL, 20
are black and dotted black. A thick deposited and (1999), 572.
etched silicide on gate; and a thin, self-aligned Kittl, J.A. et al: Salicides and alternative technologies for
silicide on source/drain areas. future ICs: Part I, Solid State Technol., (1999), 81; Part II
August 1999, p. 55.
Lasky, J.B. et al: Comparison of transformation to low-
resistivity phase and agglomeration of TiSi 2 and CoSi 2 , IEEE
TED, 38 (1991), 262.
Mann, R.W. et al: Silicides and local interconnections for high-
performance VLSI applications, IBM J. Res. Dev., 39 (1995),
403.