Study of High Frequency Acoustic Wave Attenuation in Semiconductor Silicon at Different Temperatures

The Hooke's law is perfectly obeyed in perfectly elastic solids, where even a small amplitude wave can propagate with undiminished amplitude and intensity. But, most of the real solids show a deviation from perfectly elastic behaviour, and exhibit "anharmonicity". As a result, a high frequency acoustic wave travelling through real solids gets attenuated. In present work, on the basis of theory of elasticity and making use of higher order elastic constants in solids some aspects of elastic and acoustic properties of semiconductor silicon are studied. Assuming a temperature dependent lattice parameter and non-linearity parameter, D_L, the acoustic wave attenuation is calculated. The losses leading to attenuation are attributed to phonon-phonon interactions. Theoretically calculated values of D_L and attenuation are compared with experimental values of D_L and attenuation obtained by W.P. Mason. A good agreement between the theoretical and experimental values proves the correctness of our approach.