Study of microstructure and resistivity evolution for electroplated copper films at near-room temperature

Self-annealing and aging effect characterization on copper seed thin films

“…3). This result is in agreement with work by Teh et al [5] where a good correlation between surface roughening and sheet-resistance decrease is reported.…”

“…This value is much lower than the one reached by the self-annealed sample after 200 h from deposition ($2.70 lX cm). However, the resistivity value reached by the vacuum annealed sample is still far from the reported value of bulk copper (1.7 lX cm) [5]. This difference is related to the low thickness of the copper seed layer, where the grain growth evolution is limited by the two-dimensional constraints.…”

“…Room temperature recrystallization of copper is a well-known physical phenomenon which has been widely studied since the introduction of copper as conductive material for back-end of line (BEOL) advanced metallization interconnects in the IC industry [1][2][3][4][5][6][7][8]. Several works based both on blanket and structured wafers have been presented demonstrating the dependency of the so-called ''self-annealing effect'' from a reorganization of copper lattice [1,3].…”

Nanoscale Electrodeposition of Copper on an AFM Tip and Its Morphological Investigations

“…Litearture reports (Chang, 2001) describe that increase in plating current density increased the surface roughness and reduced the grain size of copper films due to an increase of plating overpotential. Several other researchers have demonstrated that the polarization overpotential increased with increasing the plating current density leading to high copper nucleation rate (Takahashi & Gross, 1999a, 2000Tean et al, 2003;Teh et al, 2001). …”

Recrystallization of Electrodeposited Copper Thin Films During Annealing

“…Here, it can be observed that the asdeposited resistivity (2.2 lX cm) is higher than the bulk resistivity of copper at room temperature (1.7 lX cm). 13 During the initial stage of continuous heating, the film resistivity increases linearly with temperature due to the increase in electron scattering. Subsequently, the resistivity decreases gradually, indicating an increase in the average grain size of the film due to recrystallization.…”