Enhanced cracking in Si/B-doped Si0.70Ge0.30/Si heterostructures via hydrogen trapping effect.

Hydrogenation-induced cracking in Si/B-doped Si_0.70Ge_0.30/Si heterostructure with ultralow dose hydrogen implantation (3 × 10¹⁶/cm²) is demonstrated. The thickness of the Si_0.70Ge_0.30 interlayer, embedded between a 240 nm thick Si capping layer and the Si substrate, is 15 nm. After hydrogen implantation, long range H migration and trapping occurred in the Si_0.70Ge_0.30 interlayer are observed. Moreover, the crack is found to be closely correlated to the concentration of B atoms doped in the buried Si_0.70Ge_0.30 layer. With increasing B concentrations, the trapped H increases, leading to a smooth cracking confined in the Si_0.70Ge_0.30/Si interface, and fewer defects are found in the Si capping layer. In conjunction with plasma activation and wafer bonding, the as-transferred Si-on-insulator possesses a rather smooth surface (0.24 nm) and low threading dislocation density (4.4 × 10⁵ cm⁻²). [ABSTRACT FROM AUTHOR]