[11p-W321-1~14] 13.9 Compound solar cells

[11p-W321-8] Hydrogel-mediated semiconductor wafer bonding

〇Kodai Kishibe¹, Katsuaki Tanabe¹ (1.Kyoto Univ.)

Keywords:wafer bonding, hydrogel, multijunction solar cell

Hydrogel-mediated semiconductor wafer bonding has been demonstrated for low-cost fabrication of high-efficiency lattice-mismatched multijunction solar cells. Wafer direct bonding cannot be applied when wafers have roughness or in the presence of particles. This bonding scheme benefits from high surface roughness and particulate tolerances, optical transmittance, and electrical conductivity by utilizing an adhesive and viscous hydrogel. We have compared three types of hydrogels and each of them had sufficient transmittance, bonding strength, and conductivity for the fabrication of high-efficiency multijunction solar cells.