Low temperature InP layer transfer onto Si by helium implantation and direct wafer bonding
Helium implantation-induced layer splitting of InP in combination with direct wafer bonding was utilized to achieve low temperature layer transfer of InP onto Si(1 0 0) substrates. InP(1 0 0) wafers with 4 inch diameter were implanted by 100 keV helium ions with a dose of 5 × 1016 cm−2. Then the as-implanted wafers were coated with a spin-on glass (SOG) oxide having a thickness of 150 nm. The SOG coated InP wafers were subsequently bonded to thermally oxidized Si(1 0 0) handle wafers and the bonded wafer pairs were annealed at 200 °C for 20 h to achieve InP layer transfer onto Si(1 0 0) wafers, enabling monolithic integration of InP with Si. Cross-sectional transmission electron microscope images of the transferred InP layers revealed that the layers were about 650 nm thick, which consisted of a heavily damaged InP layer about 300 nm thick directly at the surface and a remaining 350 nm thick layer with considerably less damage.