BN/CN/TiN Materials and Heterostructures

This task focuses on the development of BN-CN-TiN thin films –based structures for applications in microelectronics (field emitters, MIS, LEDs, and detectors), micro-power devices (high energy density storage capacitor at high temperatures, high frequency switching power supplies), and passive hard coatings.

Thin Films Multilayer Ceramic Capacitor Chips (MLC3’s)

There is a great need for miniaturized, high power density, low cost capacitors that operate at high frequency and can sustain high operating temperatures. Besides military applications such as firing systems (lasers and triggering devices) there are other civilian applications as well.Examples are energy conversion and storage devices, high power switching power supplies, power transmission devices, and control circuitry for automotive and aerospace engines. As part of a BMDO contract, we investigated the use of III-N layers for such devices. Advantages of these nitrides include high temperature and chemical resistance which should result in more compact, reliable and performant devices.

Field emission-based microsensors for MEMS on silicon chip

The objective of this project is to develop boron nitride (BN) and carbon nitride (CN) based flat cold cathode electron emitters for microsensors operating under both vacuum and near atmospheric pressure for an extended range of temperatures. The fundamental research aims to develop flat cathode layers for applications in microdevices that can be integrated with microelectromechanical (MEMS) systems such as flow and chemical sensor, cooling devices, and actuators for several industrial, space, research, and military applications.
Compact, fast, temperature and corrosion insensitive microsensor devices can replace existing commercially available piezoresistive and capacitive pressure sensors in applications requiring corrosion media or high temperatures. The main application is the development on a Si substrate of a corrosion resistant gas/liquid delivery system. Such a system will incorporate a multi channel manifold with individually addressed and controlled flow, pressure and chemical sensing channels.

Deposition of BN/CN/Ti(N) Multilayer Coating for Tribological Applications

We have demonstrated growth of thin BN, CN and TiN films on several substrates (semi-insulating and highly doped silicon, cubic and hexagonal silicon carbide, sapphire, borane silicate, molybdenum, gallium nitride, diamond, and stainless steel). The deposited insulating BN thin layers mechanically hard (Knoop hardness values of ~ 3350 kg/mm²), uniform (rms roughness ~ 15.0 Å), very smooth surface (coefficient of friction of 0.34 is slightly lower than the value measured from stoichiometric TiN, a widely used hard coating) and porosity free materials. In terms of high temperature applications, BN films show good thermal stability up to 1000 °C after thermal vacuum annealing. The combined superior smoothness with respectable friction and hardness properties makes our BN material a good candidate for coating applications (including corrosive and high temperature environments).