In recent years, high temperature semiconductors have been utilized in wireless telemetry systems for use in military and commercial applications, wherein a high temperature environment combined with other factors such as rotating machinery or weight-constraints preclude the use of conventional silicon based wireless telemetry or wired sensor solutions. Present systems include those which can measure temperatures, pressures, vibrations, and strains. By combining the advanced electronics developed for these systems with novel sensor elements created using chemical vapor deposition (CVD) nanodiamond technology, a wide range of other high temperature sensing systems can be enabled.
The unique properties of the diamond sensors have proven in principle the capability to sense, with quantifiable signal, a wide variety of parameters under extreme conditions including very high temperatures and pressures. It has been clear for some time that diamond would be the ideal material of choice for solid-state sensors, but only in recent years has the advent of CVD diamond (as opposed to natural or HPHT [high pressure, high temperature] formation) opened the door for its practical development into harsh environment sensor systems. By combining these diamond sensor elements with high temperature electronics and high temperature packaging approaches, smart sensors can be developed to measure parameters ranging from gas chemical species on the surface of Venus, to neutron flux rates outside of a nuclear reactor core. The research presented here is centered around the use of hybrid diamond sensors for neutron detection applications in Nuclear Thermal Propulsion systems. The current technology state and development needs for these hybrid high temperature diamond smart sensors will be highlighted to potentially encourage future R&D from the high-temperature electronics community.
