Breakdown transients in high-k multilayered MOS stacks: Role of the oxide-oxide thermal boundary resistance

Abstract

In this work, breakdown transients of multilayered gate oxide stacks were analyzed to study the impact of the interfaces between oxides on the heat dissipation considering an electromigration-based progressive breakdown model. Using two distinct measurement setups on four different sets of samples, featuring two layers and three layers of Al 2 O 3 and HfO 2 interspersed, the breakdown transients were captured and characterized in terms of the degradation rate. Experimental results show that the number of oxide-oxide interfaces present in the multilayered stack has no visible impact on the breakdown growth rate among our samples. This strongly supports the interpretation of the bulk materials dominating the heat transfer to the surroundings of a fully formed conductive filament that shows no electrical differences between our various multilayered stack configurations.