Current and Temperature Sensing via Light Emission from GaN PN Junctions
Abstract
With the growing complexity of high-power converters, it has never been more important to have accurate sensors for optimal control and stability. With significantly better power handling than silicon materials, bulk gallium nitride based devices can withstand high voltages and current while simultaneously emitting a unique light spectrum, the characteristics of which are a function of the current and temperature of the device. Using bulk GaN PN junctions, preliminary measurements of the emitted light showed a distinct multi-peak spectrum corresponding to excitonic and impurity-assisted optical processes. Optical filters and photodiodes are utilized to measure the light intensity of each spectral peak for up to 5 A applied current at a temperature range of 20 C 100 C. Linear polynomial models fitted to the filter output show a strong relationship between the light intensity, current, and temperature, as well as a significant energy shift in light emitted through exciton annihilation. The experimental data is then used to fit a linear polynomial model estimating current from temperature and filter output. Mean errors of 2.5 , 2.7 , and 3.7 are achieved for three of the four current models. Recommendations are made for future work in utilizing the sensor data for real-time current and temperature measurements.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2019
- Accession Number
- AD1194041
Entities
People
- Maeve A Broeg
Organizations
- Naval Postgraduate School