Deposition behavior and substrate dependency of ALD MnOx diffusion barrier layer

Abstract

We investigated the possibility of applying an ALD method to form a Cu diffusion barrier layer of MnOx in an attempt to develop a deposition process which would not be influenced by absorbed water in a substrate. The MnOx formed by ALD using (EtCp)2Mn and H2O had the following features. (1) Capability of thickness control of the MnOx layer by changing the ALD cycle number. (2) Capability of the ALD-MnOx formation on low-k dielectrics by surface modification. (3) Good adhesion of the Cu/ALD-MnOx/SiOCH structure showing a fracture toughness of 0.3 MPa·m1/2. (4) Good diffusion barrier property for the thickness of over 1 nm. (5) Minimizing via resistance increase accompanied by the formation of MnOx on Cu.