Assessment of the strain of InP films on Si obtained by HVPE conformal growth

The strain of conformal LnP films on Si substrate grown by HVPE from GaAs seeds has been investigated by photoluminescence and X-ray diffraction measurements. A weak tensile strain (E// = 1.3x10-3 at 300 K) is observed in the GaAs seeds grown by MOCVD. It is induced by the difference of the thermal dilatation of GaAs and Si lattices between growth and room temperatures. In contrast, InP lateral films are found quasi relaxed at 300 K. They present a low density of dislocations because of the defect blocking mechanism inherent to the crystal refining technique. Conformal growth is a promising technique to achieve monolithic III-V devices integration on Si chips