InP membranes have been bonded oxide mediated onto a patterned and unpatterned Si substrate. Indentation is shown to allow local testing on patterned areas. Both responses on patterned and unpatterned are compared and placed in reference to oxide free bonded membranes. Delamination of the membrane was observed to depend on the presence of patterns in the Silicon substrate. It occurs when the indenting load reached 55 mN for an oxide mediated bonded unpatterned structure and 42 mN for an oxide mediated bonded patterned one. This is in both cases below the value of 80 mN obtained for an oxide free bonded membrane (unpatterned). Weibull analysis of these events yielded a modulus m of magnitude 6 to 10, indicating that delamination fracture is relatively predictable with a weaker resistance obtained in patterned oxide mediated bonding. Delamination of the membrane is the result of constraint of plastic flow by the InP/Si interface. Membrane rotation is induced and increases with the indentation load, until it is sufficient to initiate and propagate an interfacial crack.

Instrumented nanoindentation and STEM have been combined ex situ to study the adhesion of 450 nm thick InP membranes to Si substrates. Three distinct regimes are identified in the deformation of the InP/Si stacks during these experiments: the first is plastic flow of InP at low loads; the second is elastic debonding of the InP membrane, far from the indented zone at medium loads; lastly, the local amorphisation of the underlying Si substrate at high loads. The regime of intermediate loads is shown to be particularly useful in the evaluation of the surface bonding energy of InP to Si.

InP membranes have been bonded both oxide free and oxide mediated onto a Si substrate. The mechanical responses of the obtained thin (0.4 µm) membranes could be tested by nanoindentation and compared. Delamination of the membrane was observed to occur when the indenting load reached 55 mN for an oxide mediated bonded structure and 80 mN for an oxide free bonded one. Weibull analysis of these events yielded a modulus m of magnitude 6 to 10, indicating that delamination fracture is relatively predictable with a stronger interface obtained in oxide free approach. Delamination of the membrane is the result of constraint of plastic flow by the InP/Si interface. Membrane rotation is induced and increases with the indentation load, until it is sufficient to induce and propagate an interfacial crack.

New fabrication routes for hybrid photonic devices are explored. We report on silicon bonding to III-V semi-conducteurs e.g. Si/InP for emission/amplification function. The materials have been bonded to silicon since it can be nanostructured to obtain optical guides. The bonded surfaces are of the order of ∼ 1 cm2. Special attention has been paid to the surface preparation. The obtained structure has been characterized employing XRD while the mechanical response and interface strength have been investigated employing instrumented nanoindentation.