Terahertz-elasticity for single crystal silicon

Abstract Terahertz radiation has been used to obtain material's internal information because of its penetrability to optically opaque materials. In this paper, terahertz radiation is adopted to characterize the stress in single crystal silicon. Firstly, a theoretical model is established to describe the relationship between the phase retardation of the terahertz radiation and the stresses undergone by silicon specimen. Then, the stress-optical coefficients of single crystal silicon are determined as π11=5.2 × 10−13 Pa−1, π12=-8.4 × 10−13 Pa−1, π44=9.8 × 10−13 Pa−1 through uniaxial compression experiments. At last, an experimental technique is developed to determine the stress components of a state of plane stress of single crystal silicon.