Interface fracture and chemistry of a tungsten-based metallization on borophosphosilicate glass

Abstract

In microelectronic devices, the interface between barrier metal and dielectric is of particular interest for a reliable electronic functionality. However, it is frequently observed that this interface is prone to failure. In this work, the strength of interfaces between an as-deposited borophosphosilicate dielectric glass (BPSG) layer and a W(Ti) metallization with and without Ti interlayer was the centre of interest. Four-point-bending tests were used for the mechanical characterization combined with a topological and chemical analysis of the fracture surfaces. In addition, the interface chemistry was studied locally prior to the testing to search for a possible Ti enrichment at the interface. The fracture results will be discussed taking the chemical and topological information into account.

Keywords:

• 4-point bending
• W(Ti)/BPSG interface
• interface energy release rate

Acknowledgement

B.V. wants to thank T. Detzel and J. Fugger of Infineon Technologies Austria AG for their support.

Funding

Part of this work was jointly funded by the Austrian Research Promotion Agency [FFG, Project No. 831163] and the Carinthian Economic Promotion Fund [KWF, contact KWF-1521|22741|34186].

Notes

1. Calculated using CASINO v2.48 (2.4.8.1)