Kinetics study of NiPt(10 at.%)/Si0.7Ge0.3 solid state reactions

•Phase sequence of solid state reactions of ultra-thin 7 nm NiPt(10%) films with a Si0.7Ge0.3 layer.•In situ X-ray diffraction and sheet resistance (four point probes) measurements.•Hexagonal θ-(Ni1−yPty)2(Si1−xGex).•Kinetics study by Kissinger analysis and finite difference simulations.

For 14 nm node and beyond, p-MOS planar transistor on fully depleted silicon on insulator (FD-SOI) substrate implements Si1−xGex source and drain as stressors to enhance hole mobility in the channel. Consequently, the Ni based germano-silicidation is required to reduce contact resistivity. However, major issues are film agglomeration and Ge out-diffusion. This paper focuses on the solid state reactions of ultra-thin 7 nm NiPt(10 at.%) films with a Si0.7Ge0.3 layer. In situ X-ray diffraction and sheet resistance (four point probes) measurements were carried out simultaneously to characterize the phase sequence and kinetics. Three phases have been observed and their activation energies have been extracted using the Kissinger method. Finite difference simulations have been applied to define a growth model for the first phase.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide