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The kinetics of intermediate phase formation between ultrathin films of Pd (12 nm) and single-crystalline Si (100) is monitored by in-situ nanocalorimetry at ultrafast heating rates. The heat capacity curves show an exothermic peak related to the formation of Pd2Si. A kinetic model which goes beyond the conventional linear-parabolic growth to consider independent nucleation and lateral growth of Pd2Si along the interface and vertical growth mechanisms is developed to fit the calorimetric curves. The model is used to extract the effective interfacial nucleation/growth and diffusion coefficients at the unusually high temperatures of silicide formation achieved at very fast heating rates. [ABSTRACT FROM AUTHOR]

Abstract: Thin film based nanocalorimetry is a powerful tool to investigate nanosystems from a thermal point of view. However, nanocalorimetry is usually limited to amorphous or polycrystalline samples. Here we present a device that allows carrying out experiments on monocrystalline silicon. The monocrystalline silicon layer consists of the device layer from a silicon-on-insulator wafer and lies on a low-stress free-standing silicon nitride membrane. We applied a number of characterization techniques to determine the purity and quality of the silicon layer. All these techniques showed that the silicon surface is as pure as a standard silicon wafer and that it is susceptible to standard surface cleaning procedures. Additionally, we present a numerical model of the nanocalorimeter, which highlights that the silicon layer acts as a thermal plate thereby significantly improving thermal uniformity. This nanocalorimeter constitutes a promising device for the study of single-crystal Si surface processes and opens up an exciting new field of research in surface science. [ABSTRACT FROM AUTHOR]