TY - GEN
T1 - Influence of macro- And nanotopography, thin film thermomechanical behavior and process parameters on the stability of thermocompression bonding
AU - Stamoulis, Konstantinos
AU - Mark Spearing, S.
PY - 2004/1/1
Y1 - 2004/1/1
N2 - The quality of wafer-level, gold thermocompression bonds is critically dependent on the interaction between the wafer topography, the thin film properties, the process parameters and tooling used to achieve the bonds. This study presents mechanics modeling of the effect of wafer topography. An analytical expression for the strain energy release rate associated with the elastic deformation required to overcome wafer bow is developed. Furthermore, a simple contact yielding criterion is used to examine the pressure and temperature conditions required to flatten nano-scale asperities in order to achieve bonding over the full apparent area. The analytical results combined with experimental data for the interface bond toughness obtained from four-point bend testing indicate that the overall wafer shape is a negligible contributor to bond quality. A micro-scale bond characterization based on microscopic observations and AFM measurements show that the bond yield is increased with increasing bond pressure.
AB - The quality of wafer-level, gold thermocompression bonds is critically dependent on the interaction between the wafer topography, the thin film properties, the process parameters and tooling used to achieve the bonds. This study presents mechanics modeling of the effect of wafer topography. An analytical expression for the strain energy release rate associated with the elastic deformation required to overcome wafer bow is developed. Furthermore, a simple contact yielding criterion is used to examine the pressure and temperature conditions required to flatten nano-scale asperities in order to achieve bonding over the full apparent area. The analytical results combined with experimental data for the interface bond toughness obtained from four-point bend testing indicate that the overall wafer shape is a negligible contributor to bond quality. A micro-scale bond characterization based on microscopic observations and AFM measurements show that the bond yield is increased with increasing bond pressure.
UR - http://www.scopus.com/inward/record.url?scp=34249875955&partnerID=8YFLogxK
U2 - 10.1557/proc-854-u9.11
DO - 10.1557/proc-854-u9.11
M3 - Conference contribution
AN - SCOPUS:34249875955
SN - 1558998063
SN - 9781558998063
T3 - Materials Research Society Symposium Proceedings
SP - 208
EP - 213
BT - Stability of Thin Films and Nanostructures
PB - Materials Research Society
T2 - 2004 MRS Fall Meeting
Y2 - 29 November 2004 through 3 December 2004
ER -