Abstract
The interfacial reactions of Ni with polycrystalline Si 0.8 Ge 0.2 films at a temperature range of 300-900°C by rapid thermal annealing for 60s are studied. The sheet resistances of the silicide films were relatively low at ~10 ohm/sq for samples annealed below 600°C. X-Ray diffraction results suggested the existence of low resistivity phase Ni(Si 1-x Ge x ) in the film. The significant increase in sheet resistance for films annealed at 700-900°C is probably due to the reduction in the density of Ni(Si 1-x Ge x ) as a result of fast Ni diffusion at high annealing temperatures. Fast grain boundary diffusion of Ni was suggested to cause the lowering of formation temperature of Ni(Si 1-x Ge x ) on polycrystalline Si 1-x Ge x films. Rutherford backscattering results showed that for films annealed at a temperature range of 300-600°C, Ni has reacted with the polycrystalline films. However, at an annealing temperature higher than 700°C, Ni diffused through the whole film.