Fracture strength and biaxial modulus measurement of plasma silicon nitride films

Abstract

The biaxial modulus, ultimate tensile strength and residual stress of silicon nitride films are investigated using the bulge test technique. These films are deposited by plasma-enhanced chemical vapor deposition on gallium arsenide substrates. Biaxial moduli of films 1 μm thick with two different chemical compositions were measured. The nitrogen-rich composition has a biaxial modulus of 160 GPa and an ultimate tensile strength of 420 MPa, while the silicon-rich composition has a biaxial modulus of 110 GPa and an ultimate tensile strength of 390 MPa. A comparison with previously reported mechanical properties for silicon nitride films is discussed.