Interfacial Characterizations of a Nickel-Phosphorus Layer Electrolessly Deposited on a Silane Compound-Modified Silicon Wafer Under Thermal Annealing
- 134 Downloads
Front-side metallization of a Si wafer was carried out using electroless deposition of nickel-phosphorus (Ni-P) catalyzed by polyvinylpyrrolidone-capped palladium nanoclusters (PVP-nPd). A 3-[2-(2-Aminoethylamino)ethylamino] propyl-trimethoxysilane (ETAS) layer was covalently bonded on the Si surface as bridge linker to the Pd cores of PVP-nPd clusters for improving adhesion between the Ni-P layer and the Si surface. To investigate the effects of an interfacial ETAS layer on the Ni silicide formation at the Ni-P/Si contact, the Ni-P-coated Si samples were thermally annealed via rapid thermal annealing (RTA) from 500°C to 900°C for 2 min. To compare with the ETAS sample, the sputtered Ni layer on Si and electroless Ni-P layer on ion-Pd-catalyzed Si (both are standard processes) were also investigated. The microstructural characterizations for the Ni-P or Ni layer deposited on the Si wafer were performed using x-ray diffractometer, scanning electron microscopy, and transmission electron microscopy. Our results showed that the ETAS layer acted as a barrier to slow the atomic diffusion of Ni toward the Si side. Although the formation of Ni silicides required a higher annealing temperature, the adhesion strength and contact resistivity measurements of annealed Ni-P/Si contacts showed satisfactory results, which were essential to the device performance and reliability during thermal annealing.
KeywordsAnnealing diffusion microstructures electroless nickel
Unable to display preview. Download preview PDF.
- 1.A. Brenner, C. Chase, and G.E. Riddell, U.S. patent US 2,532,283 (1950).Google Scholar
- 5.C.R. Jr. Shipley, U.S. patent 3,011,920 (1961).Google Scholar
- 19.K.J. Lee and P. Nash, Phase Diagrams of Binary Nickel Alloys (Park: ASM Materials, 1991).Google Scholar
- 22.J. Foggiato, W.S. Yoo, M. Ouaknine, T. Murakami, and T. Fukada, Mater. Sci. Eng. B. 56, 114–115 (2004).Google Scholar
- 25.L. Tous, D.H. Van Dorp, R. Russell, J. Das, M. Aleman, H. Bender, J. Meersschaut, K. Opsomer, J. Poortmans, and R. Mertens, Energy Procedia (Amsterdam: Elsevier, 2011), pp. 39–46.Google Scholar