The Semiconductor Material and Device Sciences Department (1873) is engaged in compound semiconductor physics and device research, with parallel and complementary efforts in fundamental science and novel device technologies, within the Center for Material, Physical, and Chemical Sciences (1800). One of several current focus areas is III-Nitride based materials and devices for power electronics and other applications, which has enormous short- and long-term potential for Sandias national security missions. Other ongoing efforts include radiation effects, reliability physics, defect spectroscopy, and magnetic materials. The department's research utilizes staff expertise in experimental and theoretical semiconductor physics, state-of-the-art micro- and nano-fabrication, and advanced materials and device characterization and modeling. It partners closely with other organizations, including the Advanced Electronic and Optoelectronic Materials Department (1876), other departments in Centers 1300, 5200, 8800, and elsewhere within Sandia, as well as university and industry collaborators throughout the world. The department makes use of state-of-the-art growth and fabrication facilities associated with MESA (Sandia's Microsystems Engineering, Science, and Applications complex); scientific facilities at CINT (the joint Sandia / Los Alamos Center for Integrated Nanotechnologies); and staff laboratories with specialized characterization equipment.