In this paper we present a new, innovative technologyfor fabrication and integration of free-hanging transducers.The transducer structures are processed on the originalsubstrate wafer (sacrificial device wafer) and then transferredto a new substrate wafer (target wafer). The technology consists only of low-temperature processes, thus it iscompatible with integrated circuits. We have applied the newmembrane transfer bonding technology to the fabrication ofinfrared bolometers for use in uncooled infrared focal planearrays (IRFPAs). In the future this may allow bolometers to beintegrated with high-temperature-annealed, high-performance thermistor materials on CMOS-based uncooled IRFPAs. Membranetransfer bonding is based on low-temperature adhesive bondingof the sacrificial device wafer to the target wafer. Thedevice wafer is sacrificially removed by etching or by acombination of grinding and etching, while the transducer structures remain on the target wafer. The transducer structuresare mechanically and electrically contacted to the target waferand the adhesive bonding material is sacrificially removed. Thefree-hanging transducers remain on the target wafer. One of theunique advantages of this technology is the ability tofabricate and integrate free-hanging transducers with very small feature sizes. In principle, membrane transfer bonding canbe applied to any type of free-hanging transducer includingferroelectric infrared detectors, movable micro-mirrors and RFMEMS devices.