Fishing – trapping – and vermin destroying
Patent
1993-10-29
1996-04-23
Fourson, George
Fishing, trapping, and vermin destroying
437247, 148DIG40, 148DIG147, H01L 2144
Patent
active
055102956
ABSTRACT:
The phase transformation temperature of a metal silicide layer formed overlying a silicon layer on a semiconductor wafer is lowered. First, a refractory metal is disposed proximate to the surface of the silicon layer, a precursory metal is deposited in a layer overlying the refractory metal, and the wafer is heated to a temperature sufficient to form the metal silicide from the precursory metal. The precursory metal may be a refractory metal, and is preferably titanium, tungsten, or cobalt. The concentration of the refractory metal at the surface of the silicon layer is preferably less than about 10.sup.17 atoms/cm.sup.3. The refractory metal may be Mo, Co, W, Ta, Nb, Ru, or Cr, and more preferably is Mo or Co. The heating step used to form the silicide is performed at a temperature less than about 700.degree. C., and more preferably between about 600.degree.-700.degree. C. Optionally, the wafer is annealed following the step of disposing the refractory metal and prior to the step of depositing the precursory metal layer. Preferably, this annealing step is performed at a wafer temperature of at least about 900.degree. C.
REFERENCES:
patent: 4777150 (1988-10-01), Deneuville et al.
patent: 4786611 (1988-11-01), Pfiester
patent: 4800177 (1989-01-01), Nakamae
patent: 4837174 (1989-06-01), Peterson
patent: 4981816 (1991-01-01), Kim et al.
patent: 5043300 (1991-08-01), Nulman
patent: 5093280 (1992-03-01), Tully
patent: 5102826 (1992-04-01), Ohshima et al.
patent: 5108954 (1992-04-01), Sandhu et al.
patent: 5122479 (1992-06-01), Audet et al.
patent: 5138432 (1992-08-01), Stanasolovich et al.
patent: 5457069 (1995-10-01), Chen et al.
Y. Misawa, et al. "Silicidation of Molybdenum and Titanium Double Layers" J. Electrochem. Soc. 137(2) (Feb. 1990) pp. 713-717.
K. L. Wang et al "Refractory Metal Silicide Formation by Ion Implantation" Thin Solid Films 74 (1980) pp. 239-244.
Fann--Mei Yang, et al. "Phase Transformation of Mo and Wover Co or its alloy in contact with Si" Phase Transformations in thin films thermo.and kinetics Symp. 13-15 Apr. 1993 pp. 329-334, Mater. Res. Soc.
Fann--Mei Yang, et al. "Formation of Bilayer Shallow MoSi.sub.2 /CoSi.sub.2 Salicide Contact" Jpn. J. Appl. Phys. vol. 31 (1992) pp. 1004-1011, Part 1, No. 4, Apr. 1992.
Fann--Mei Yang, et al. "Phase Transformation of Mo and Wover Co or its alloy in contact with Si" Thin Solid Films, 238 (1994) pp. 146-154.
Electrochem. Soc. Extended Abstr. Abstr. No. 147, Spring Meeting 1992.
Liu et al. "Growth of expitaxial CoSi.sub.2 film on Si(100) substrate induced . . . " Materials Letters 17, 383-387 (1993).
Ben-Tzur et al. "Interfacial reactions between thin films of Ti-Ta and single . . . " J. Vac. Science & Tech. 5, 2721-2726 (1991).
Sakai et al. "A New Salicide Process (PASET) for Sub-half Micron CMOS" 1992 Symposium on VLSI Technology, 66-67.
Fung et al. "Localized epitaxial growth of C54 and C49 TiSi.sub.2 on (111)Si" App. Phys. Lett. 47, 1312-1314 (1985).
Mann, R. W. and Racine, C. A., "Microstructure Control and Thermal Stability of Titanium Silicide", Electrochemical Society, Extended Abstract 272, Spring Meeting (1992).
Mann, R. W. et al, "Nucleation, Transformation and Agglomeration of C54 Phase Titanium Disilicide", Materials Research Society Symposium Proceedings, vol. 224, p. 115 (1991).
VanHoutum, Harrie and Raaijmakers, Ivo, "First Phase Nucleation and Growth of Titanium Disilicide With An Emphasis on the Influence of Oxygen", Materials Research Society Symposium, 1986.
Thompson, R. D. et al., "Effect of a Substrate on the Phase Transformations of Amorphous TiSi.sub.2 Thin Films", Journal Applied Physics vol. 61(2) 15, Jan. 1987.
Lasky, J. B. et al., "Comparison of Transformation to Low-Resistivity Phase and Agglomeration of TiSi.sub.2 and CoSi.sub.2 ", IEEE Transactions on Electron Devices, vol. 38, No. 2, Feb. 1991.
Liu et al., "Effects of Sb on Phase Transformations of Amorphous TiSi.sub.2 Thin Films", Journal of Applied Physics 72(2) 15 Jul. 1992.
d'Heurle, F. M. and Harper, J. M., "Alloying of TiSi.sub.2 ", IBM Technical Disclosure Bulletin, vol. 33, No. 7, Dec. 1990.
Mann et al., "Phase Transformation Kinetics of TiSi.sub.2 ", Materials Research Society Symposium Proceedings, vol. 311, p. 281 (1993).
Mann et al., "The C49 to C54-TiSi.sub.2 Transformation in Salicide Applications", Journal of Applied Physics, vol. 73, No. 7, p. 3566 (1993).
Mann et al., "Low Temperature Nitridation of TiSi.sub.2 ", Electrochemical Society, Extended Abstract, Fall Meeting 1987.
Koch, Tim, "Effects of Dopants in Polysilicon on Titanium Silicide Degradation", Electrochemical Society, Extended Abstract, Abstract No. 147, Spring Meeting 1992.
Cabral, Jr. Cyril
Clevenger Lawrence A.
D'Heurle Francois M.
Harper James M. E.
Mann Randy W.
Everhart C.
Fourson George
International Business Machines - Corporation
LandOfFree
Method for lowering the phase transformation temperature of a me does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for lowering the phase transformation temperature of a me, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for lowering the phase transformation temperature of a me will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2308254