Compact passive devices in InP membrane on silicon

The high vertical index contrast and the small thickness of thin InP membranes (200nm) bonded with BCB allow the achievement of very small devices. In this paper we will present some performances of such photonic integrated circuit building blocks (wires, 3dB splitters and ring resonators)

Efficiency Enhancement of InP Nanowire Solar Cells by Surface Cleaning

We demonstrate an efficiency enhancement of an InP nanowire (NW) axial p–n junction solar cell by cleaning the NW surface. NW arrays were grown with <i>in situ</i> HCl etching on an InP substrate patterned by nanoimprint lithography, and the NWs surfaces were cleaned after growth by piranha etching. We find that the postgrowth piranha etching is critical for obtaining a good solar cell performance. With this procedure, a high diode rectification factor of 10⁷ is obtained at ±1 V. The resulting NW solar cell exhibits an open-circuit voltage (<i>V</i>_oc) of 0.73 V, a short-circuit current density (<i>J</i>_sc) of 21 mA/cm², and a fill factor (FF) of 0.73 at 1 sun. This yields a power conversion efficiency of up to 11.1% at 1 sun and 10.3% at 12 suns