SBIR-STTR Award

The objective of this research is to investigate methods for the fabrication of high energy density capacitors using oxygen-doped aluminum nitride (O-AlN) films as dielectric medium and to test their performance at high temperature and high current modes. The electrical properties of amorphous (O-AlN) film make it a potential candidate for use in capacitors for pulse forming networks. Its desirable properties includes: (a) very high breakdown strength, (b) very high resistivity, (c) excellent thermal conductivity, (d) high chemical inertness to oxygen at high temperature, (e) very low dissipation factor, and (f) very high high decomposition temperature. Under this proposal it is intended to investigate: (1) optimum conditions for the growth of high quality amorphous O-AlN films on aluminum foil, glass and silicon wafer, and (2) the fabrication of prototype high energy density of O-AlN capacitors, and perform high voltage and high temperature testing. The compact, high temperature and high energy density of O-AlN capacitors with high reliability have a myriad of in both commercial and military applications. The high temperature capability of O-AlN capacitors will enable high temperature electrically-driven aircraft accessories to be realized such as engine-mounted actuators and remotely mounted flight control actuactors as envisioned for the far term More Electric Aircraft (MEA), Directed Energy Weapons (DEW), Directed Energy Attack Aircraft (DE ATAC), Unmanned Combat Aerial Vehicle (UCAV) and High Power Microwave (HPM) demonstration program. The military will also benefit from O-AlN capacitors in Electric Propulsion Power Conditioning, Space Based Laser (SBL), Space Plane Power Management and Distribution (PMAD). High energy density capacitors are greatly needed for DOD pulse power applications. Also, commercial applications are widespread. These include utilities, deep-well drilling gear, power supplies, commercial aircraft, communication satellites and automobiles, medical instruments, small and large appliances

Aluminum Nitride (AlN)/Oxygen -Doped AlN (O-AlN) possess the unique properties of high dielectric strength, high resistivity, high decomposition temperature, chemical inertness, great hardness and excellent thermal conductivity. In Phase I, we demonstrated that AlN/O-AlN films can be deposited directly onto smooth aluminum surfaces with good adhesion, and that AlN/O-Aln films are highly flexible, making them suitable for the production of wound capacitors. The Phase II research will demonstrate an economical manufacturing technique using a dual magnetron sputtering system with a continuous rolling mechanism for the mass production of rolled capacitors, and will also demonstrate packaged AlN/O-AlN capacitors of high energy density, smaller size, and lower weight as compared to current film capacitors. The main objective of Phase II will involve the assembly and demonstration of a manufacturing operation which combines the AlN/O-AlN deposition system, and the capacitor rolling operation process into a single modular system housed within a 100 square foot area. The whole operation will be assembled within a clean room enclosure. This basic modular fabrication system could then be duplicated for the mass production of capacitors in the Phase III effort.

Keywords:
ALUMINUM NITRIDE, OXYGEN-DOPED ALUMINUM NITRIDE, DIELECTRIC MEDIUM, COMPACT CAPACITORS, PULSE FORMING NETWORKS