Publication

Abstract : Repair of plasma damaged nanoporous organosilicate films carried out by hexamethyldisilazane (HMDS) vapor treatment was investigated as a function of temperature. Capacitance–voltage measurements were carried out before and after {HMDS} vapor treatment. The dielectric constant measurements confirm that the {HMDS} vapor treatment facilitates only partial curing of the plasma damaged films, as also observed from the Fourier transform infrared absorption measurements. Bias temperature stress measurements for samples with copper (Cu) metal electrodes reveal a shift of − 35nbsp;V in the capacitance–voltage curve for samples cured at 55nbsp;°C whereas negligible shift is observed for samples treated above 80nbsp;°C. This behavior suggests the existence of a dense solid layer on the top surface of the samples treated above 80nbsp;°C, hindering the diffusion or movement of Cu ions into the dielectric. Direct imaging of the {HMDS} vapor treated plasma damaged films using scanning electron microscope clearly shows the existence of two distinct layers, with the top layer (at the film–air interface) being denser than the bottom layer at the film–substrate interface.