Buffer layer effects on residual stress in InP on Si substrates

Heteroepitaxial growth of InP on Si(100) substrates using InP direct growth, and with a GaAs or GaP buffer layer has been grown by organometallic vapor phase epitaxy (OMVPE). The effects of buffer layers on residual stress in InP films are examined. For InP/(GaP buffer layer)/Si, stress (∼6×108 dyn/cm2) is almost independent on buffer layer thickness and somewhat higher than that (∼4×108dyn/cm2) in InP grown directly on Si. For InP/(GaAs buffer layer)/Si, stress is as low as 2×108 dyn/cm2 with buffer layer thicknesses ≳1 μm. The GaAs buffer layer effect on reduction of stress in InP film is found to be attributed to compressive strains thermally induced by the InP/GaAs interface.