Fabrication of Si//Patterned Metal Layer/Si Junctions for Hybrid Multijunction Solar Cells with Improved Bonding Interface Properties

We successfully fabricate a p+-Si//patterned Al in alignment to SiO
₂
/p+ -Si junction by surface-activated bonding (SAB) of a p+-Si substrate and a patterned Al layer. We find that the interface resistance, which is 0.025 Ω.cm
²
in a junction annealed at 300 °C, is much lower than p+ -Si/p+ -Si junction by SAB. This result shows the superiority of junctions using patterned metal layer to directly-bonded semiconductor.