TY - JOUR

T1 - Substrate-Influenced Thermo-Mechanical Fatigue of Copper Metallizations

T2 - Limits of Stoney's equation

AU - Bigl, Stephan

AU - Wurster, Stefan

AU - Cordill, Megan J.

AU - Kiener, Daniel

PY - 2017/11/9

Y1 - 2017/11/9

N2 - Rapid progress in the reduction of substrate thickness for silicon-based microelectronics leads to a significant reduction of the device bending stiffness and the need to address its implication for the thermo-mechanical fatigue behavior of metallization layers. Results on 5 µm thick Cu films reveal a strong substrate thickness-dependent microstructural evolution. Substrates with hs = 323 and 220 µm showed that the Cu microstructure exhibits accelerated grain growth and surface roughening. Moreover, curvature-strain data indicates that Stoney’s simplified curvature-stress relation is not valid for thin substrates with regard to the expected strains, but can be addressed using more sophisticated plate bending theories.

AB - Rapid progress in the reduction of substrate thickness for silicon-based microelectronics leads to a significant reduction of the device bending stiffness and the need to address its implication for the thermo-mechanical fatigue behavior of metallization layers. Results on 5 µm thick Cu films reveal a strong substrate thickness-dependent microstructural evolution. Substrates with hs = 323 and 220 µm showed that the Cu microstructure exhibits accelerated grain growth and surface roughening. Moreover, curvature-strain data indicates that Stoney’s simplified curvature-stress relation is not valid for thin substrates with regard to the expected strains, but can be addressed using more sophisticated plate bending theories.

KW - Stress

KW - Thermo-mechanical

KW - Thin films

UR - http://www.scopus.com/inward/record.url?scp=85033723779&partnerID=8YFLogxK

U2 - 10.3390/ma10111287

DO - 10.3390/ma10111287

M3 - Article

AN - SCOPUS:85033723779

VL - 10.2017

JO - Materials

JF - Materials

SN - 1996-1944

IS - 11

M1 - 1287

ER -