The recent increase in transportation costs and the push for cleaner emissions demands advancements in aerospace technology. The current instrumentation used in aerospace applications is costly, and indirect measurement approaches are often employed due to the inability to locate sensors in harsh environments. Health monitoring technologies for the development of a distributed sensor network can be utilized to improve engine efficiencies and reduce emissions while maintaining safety. This paper reviews the recent advancements in silicon carbide (SiC) process technologies and demonstrations of SiC sensors and electronic circuits in hostile environments, which supports the use of SiC technology for health and performance monitoring of aerospace systems. Further development of this technology can ultimately improve the performance, reliability, and emissions of aerospace systems. However, challenges still remain for the realization of a distributed sensor network for harsh environment applications such as aerospace.

Advances in siliconcarbide microfabrication and growth process optimization for siliconcarbide nanostructures are ushering in new opportunities for microdevices capable of operation in a variety of demanding applications, involving high temperature, radiation, or corrosive environment. This review focuses on the materials science and processing technologies for siliconcarbidethin films and low dimensional structures, and details recent progress in manufacturing technology, including deposition, metallization, and fabrication of semiconductor microdevices, with emphasis on sensor technology. The challenges remaining in developing siliconcarbide as a mainstay materials platform are discussed throughout.

We demonstrate solar-blind photodetectors (PDs) by employing AlN thin films on Si(100) substrates with excellent temperature tolerance and radiation hardness. Even at a bias higher than 200 V the AlN PDs on Si show a dark current as low as ~ 1 nA. The working temperature is up to 300°C and the radiation tolerance is up to 10¹³ cm⁻² of 2-MeV proton fluences for AlN metal-semiconductor-metal (MSM) PDs. Moreover, the AlN PDs show a photoresponse time as fast as ~ 110 ms (the rise time) and ~ 80 ms (the fall time) at 5 V bias. The results demonstrate that AlN MSM PDs hold high potential in next-generation deep ultraviolet PDs for use in harsh environments.

A Lamb wave resonator utilizing an aluminum nitride (AlN) plate with biconvex edges to enhance the quality factor (Q) is demonstrated. The simulation results based on finite element analysis verify that the use of the biconvex edges, instead of the conventional flat edges, can efficiently confine mechanical energy in the AlN Lamb wave resonator. Specifically, the measured frequency response of a 491.8-MHz AlN Lamb wave resonator with biconvex edges yields a Q of 3280 which represents a 2.6× enhancement in Q over a 517.9-MHz Lamb wave resonator on the same AlN plate but with the suspended flat edges.

Photodetectors based on the AlGaN/GaN heterostructure suffer from persistent photoconductivity (PPC) in which recovery from the optical stimulus can take days. This behavior is unsuitable for many applications where reliable and consistent optical response is required. This letter presents a method for suppressing PPC in AlGaN/GaN photodetectors by employing device suspension and in situ heating. The highly conductive two-dimensional electron gas (2DEG) at the interface of AlGaN and GaN serves as both a sensor and a heater (via Joule heating). Microfabricated AlGaN/GaN-on-Si ultraviolet (UV) photodetectors (suspended and unsuspended) were exposed to UV (365 nm) for 60 s and the transient responses were measured under various in situ heating conditions. The measured transient response showed a decay time of ~39 h when the photodetector was not heated and 24 s for a suspended photodetector with in situ 2DEG heating (270°C with a power of 75 mW). This remarkable suppression of the PPC in AlGaN/GaN UV photodetectors can be attributed to the novel device architecture and in situ heating capability, which enables acceleration of the carrier capture rate during operation.