Complementary-GaN for high-temperature electronics (C-GaN)
Final Report Abstract
GaN-based materials are expected to be excellently suited for high-temperature operation as their large bandgap range extending from 3.4 eV for GaN to 6.2 eV for AlN ensures extremely low carrier densities even up to extreme temperatures of 800°C and above. In this project, the potential of GaN technology has been systematically explored and through tight cooperation between the partners involved, major advances in the field of high-frequency/high-temperature electronics were achieved. The demonstration of a 1 GHz – 300°C oscillator is the result of extensive research, gathered know-how and technological development of the individual components comprising the oscillator as well as the ability to align the expertise of each partner to meet a common goal. The knowledge base developed in this project goes beyond the direct optimization and demonstration of the high-temperature-capable oscillator. To be able to demonstrate this project result, research and development on several fields had to be achieved simultaneously, in terms of the core GaN HEMT, the passive circuit components, and the high-temperature aspects of circuit design and characterization. Those main research aspects covered in this project include the following: • Development and optimization of GaN HEMT epitaxy enabling the device to operate at elevated temperatures and high frequencies. • Exploration of novel epitaxial structures for future advanced devices. • Development of high-temperature high-frequency active-device technology and of passive components including different dielectrics on various substrates with different thermal properties. • Upgrade and modification of HEMT device characterization tools and methods, both in DC and in small-signal, to accommodate the setup to the restrictions given by a hightemperature environment. • Modelling the high temperature characteristics of active and passive devices based on extensive measurements and successful initial evaluation of high-temperature circuit concepts. Based on the full DC and small-signal characterization of the passive devices and the HEMT transistors up to 300ºC, a full-fledged transistor model accurately describing the temperature dependence was extracted, also allowing for performance extrapolation beyond the available characterization range. Electromagnetic simulation of the full circuit layout verified the transistor model and suitability of the chosen topology. Finally, fully integrated oscillators on different PCB substrates were designed, simulated, and implemented. Good performance in agreement with simulations was measured in the up to 300ºC, i.e. the highest temperature possible in the present high-frequency set-up. The development of models, design tools, and fabrication technology of the needed high-temperature-capable passive and active components and of the carrier substrates, together with the appropriate circuit topologies, followed by characterization and evaluation at high temperatures and high frequencies, lead to the accomplishments of the main objectives of this collaborative research project.
Publications
- “Novel approach for a monolithically integrated GaN cascode with minimized conduction and switching losses”, 2018 76th Device Research Conference (DRC), Santa Barbara, CA, 2018, pp. 1-2
H. Hahn, H. Yacoub, T. Zweipfennig, G. Lükens, S. A. Kotzea, A. Debald, Arne, A. Noculak, R. Negra, H. Kalisch, A Vescan
(See online at https://doi.org/10.1109/DRC.2018.8442230) - „Polarizationinduced doping in metal-polar AlGaN“, DGKK Workshop on Epitaxy of III-V Compounds, Dresden, 5/6.12.2019
C. Beckmann, J. Wieben, H. Kalisch and A. Vescan
- "Evaluation of High-Temperature High-Frequency GaN- Based LC-Oscillator Components", IEEE Transactions on Electron Devices (special edition for ESSDERC2020), 2020, pp. 1-5
A. Ottaviani, P. Palacios, T. Zweipfennig, M. Alomari, C.Beckmann, D. Bierbüsse, J. Wieben, J. Ehrler, H. Kalisch, R. Negra, A.Vescan, J. N. Burghartz
(See online at https://doi.org/10.1109/TED.2020.3016918) - "High-Temperature Device Characterisation, Modelling and Oscillator Design," 2020 German Microwave Conference (GeMiC), Cottbus, Germany, 2020, pp. 128-131
D. Bierbüsse, T. Bürger, M. Wei and R. Negra
