Pore Sealing of Porous Ultralow-k Dielectrics by Self-Assembled Monolayers Combined with Atomic Layer Deposition

Abstract

Due to its excellent step coverage characteristics, atomic layer depositions (ALD) deposit their material not only on top of underlying surfaces but also into the pores of porous low-k films. In this study, the film characteristics caused by pre-treatments of the low-k material, followed by deposition of self assembled monolayers (SAMs) from an 11-cyanoundecyltrichlorosilane precursor and finally by an HfO2 Atomic Layer Deposition were determined. By adequate optimization of the surface treatment, the SAM deposition and the ALD it was possible to obtain complete pore sealing after ALD, without penetration of the Hf into de porous low-k film.