CHARACTERIZATION AND MODELING OF ELASTIC MODULUS ACROSS THE (Al, Sc)N SYSTEM

摘要

The doping of Sc into aluminum nitride has been found to enhance the piezoelectric response by up to 400% over pure aluminum nitride. Maximization of piezoelectric figures of merit including effective piezoelectric strain coefficient (d_(33)) and electromechanical coupling factor (k_t~2) is critical for applications such as accelerometers and energy harvesters, and both these figures of merit have an inverse relationship with the stiffness of the material. Conversely, resonant applications such as the electromechanical filters that are ubiquitous in wireless communication technologies are governed by figures of merit that are directly proportional to material stiffness. Thus, while most literature on this system focuses on a subset of easily-measured electrical or electromechanical properties, understanding fundamental origins of such responses as well as future application-specific optimization requires a better understanding of the mechanical properties of such materials.