Dual SIC photodiode devices for simultaneous two band detection

SiC is a highly useful material for optical sensing devices in the UV due to its large bandgap. It also exhibits a robust physical nature, making it suitable for harsh environment applications such as flame sensing. Here, we report the first demonstration of SiC photodiode devices with multiple, independent detection components for sensing more than one radiation band simultaneously. The fabrication process and layout of the devices will be described along with optical and electrical measurements of their performance. Individual sensing components exhibited peak responsivities greater than 60 mA/W, at wavelengths of 290 and 320 nm. Optically tailored SiC devices, such as the ones described here, may further be applied to other applications such as missile plume detection, engine control and communications in the solar-blind window. The application of particular interest for these devices was for flame temperature sensing. Testing the dual SiC photodiode devices in front of a combustion flame showed a significant and linear dependence of the photodiode's output ratio with temperature, demonstrating its feasibility. Successful determination of flame temperature would be a major improvement in the control and optimization of combustion processes.