Silicon nanowires grown by the VLS mechanism resulted as efficient chemical and biological sensors as field effect transistors, nevertheless up to date a key point is the integration of the nanostructure in actual integrated circuit. The basic requirement appears the possibility to perform the deposition at low temperature, directly on the backside of the already finished integrated circuit. This would combine the high chemical sensitivity of the nanowires with the sensitivity, the elaboration capability, and the low production cost of CMOS technology. This paper presents a new technique which allows the grow of silicon nanowires at temperature lower than 200°C. MW CVD technique is used combined with nano-susceptors.