A comparative study of ULK conduction mechanisms and TDDB characteristics for Cu interconnects with and without CoWP metal cap at 32nm technology

Author

Chen, F. ; Huang, E. ; Shinosky, M. ; Angyal, M. ; Kane, T. ; Wang, Y. ; Kolics, A.

Author_Institution

IBM Microelectron., Essex Junction, VT, USA

fYear

2010

fDate

6-9 June 2010

Firstpage

1

Lastpage

3

Abstract

As the current-carrying capability of a copper line is reduced due to interconnect dimension shrinkage, self-aligned CoWP metal-cap has been reported to be helpful to improve degraded electromigration (EM) reliability. However, adoption of this new metal cap in general further exacerbates the already problematic low-k dielectric TDDB reliability at 32nm and beyond. This paper provides a comparative study of ULK conduction mechanisms over a wide range of temperature (30°C to 295°C) and TDDB acceleration kinetics at 125°C for Cu interconnects with and without CoWP metal cap at 32nm technology. It was found that adding CoWP didn´t change the fundamental ULK leakage conduction mechanism and TDDB kinetics if its process was optimized. Comparable leakage and TDDB performance were achieved with an optimized CoWP process.

Keywords

cobalt compounds; copper; electromigration; reliability; CoWP; CoWP metal cap; Cu; Cu interconnects; TDDB characteristics; ULK conduction mechanisms; ULK leakage conduction mechanism; copper line; electromigration reliability; interconnect dimension shrinkage; low-k dielectric TDDB reliability; size 32 nm; Copper; Degradation; Dielectrics; Kinetic theory; Leakage current; Microelectronics; Stress; Temperature distribution; Testing; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Interconnect Technology Conference (IITC), 2010 International

Conference_Location

Burlingame, CA

Print_ISBN

978-1-4244-7676-3

Type

conf

DOI

10.1109/IITC.2010.5510693

Filename

5510693