Transient thermal conductivity in PECVD SiN x at high temperature: the thermal signature of an on-going irreversible modification

International audiencePECVD amorphous silicon nitride (a-SiN x) films are largely used into the dielectric stacks of integrated circuits, as passivation or capping layers, and are today an important alternative to silicon for integrated nonlinear optical applications, such as waveguides. In such applications, a-SiN x presents also the advantage of having a very low thermal conductivity, about 0.7 W/m K at room temperature, which is of relevance, as such films contribute to the thermal balance of the devices, and thus play a role in solving the thermal management problem in microelectronics. The deposition parameters, and more specificall