A superconducting linac driver, delivering deuterons with an energy up to 40 MeV (5 mA) and heavy ions with an energy of 14.5 MeV/u (1 mA), is proposed for the Spiral-2 radioactive beams facility. For the high-energy section of the linac, a superconducting 88 MHz Quarter Wave Resonator (beta 0.12) has been designed and the optimisation of RF and mechanical performances will be presented. Based on the present state-of-art of the superconducting RF technology, maximum electric surface fields of 40 MV/m and magnetic surface fields of 80 mT have been adopted, which should allow to reach an accelerating field of 7 MV/m (energy gain 3 MeV per resonator). A first complete prototype is under construction. The high intensity deuteron beam specifications have imposed the design of an original power coupler (maximum power 20 kW). The RF, mechanical, and thermal characteristics will be presented. The design of the cryomodule for this high-energy section, integrating two QWR with its associated equipments (couplers, tuners, helium tanks), is presented.