Basic: A High-Sensitivity All Silicon Bolometer Focal Plane For The Safari Instrument Aboard The Spica Observatory

The 6 K cooled primary mirror of the SPICA observatory, to be launched in 2018, allows a photometry gain in sensitivity in the far infrared of more than two orders of magnitude when compared with current instrumentation in space. All the proposed detector solutions will have to deploy radically different solutions from previous developments to cope with the extremely low background and very low power budgets available at all the temperature stages. We present the current design of very large "all Silicon" filled Bolometer Arrays cooled below 100 mK, and the solutions we develop for the BASIC (Bolometer Arrays for the All Silicon SAFARI Imaging Camera) focal planes of SAFARI. They will cover simultaneously three wavelength bands between 30 and 210 mu m.