Trade-off between Hall sensitivity, temperature stability, and frequency response in a 2DEG nitride Hall-effect sensor

We investigated the relationship between Hall sensitivity, temperature stability, and frequency response of III-nitride two-dimensional electron gas-based Hall-effect sensors. For this study, we utilized three different heterostructure designs, each with varying percentages of “Al” content in the (Al)GaN barrier layer. The relationship among Hall sensitivity, temperature stability, and frequency response was investigated by varying the 2DEG carrier mobility, sheet density, and sheet resistance of the Hall device. The investigation demonstrated and explained a trade-off of Hall sensitivity of the order of 50% to obtain a sensor with a 16% reduction in sensitivity over the temperature range from room temperature to 377 °C with a frequency bandwidth of approximately 5.8 MHz. However, in terms of input voltage utilization, AlN/GaN retains its advantages, offering high sensitivity together with enhanced frequency response.