Fabrication methods for capacitive-micromachined ultrasound transducers (“cMUT”) and cMUT imaging array systems are provided. cMUT devices fabricated from low process temperatures are also provided. In an exemplary embodiment, a process temperature can be less than approximately 300 degrees Celsius. A cMUT fabrication method generally comprises depositing and patterning materials on a substrate (400). The substrate (400) can be silicon, transparent, other materials. In an exemplary embodiment, multiple metal layers (405, 410, 415) can be deposited and patterned onto the substrate (400); several membrane layers (420, 435, 445) can be deposited over the multiple metal layers (405, 410, 415); and additional metal layers (425, 430) can be disposed within the several membrane layers (420, 435, 445). The second metal layer (410) is preferably resistant to etchants used to etch the third metal layer (415) when forming a cavity (447). Other embodiments are also claimed and described.