Photovoltaic power converters with a GaAs active region are designed for surface normal quasi-monochromatic illumination. An underlying AlInP etch release layer allows heterogeneous integration of the devices onto non-native substrates by Micro- Transfer Printing (µTP). The converters are particularly relevant for integration onto to photonics integrated circuits where electrical isolation between components is necessary. Remote power can be delivered to a circuit as and when needed.