Authors
Institute of High Pressure Physics Polish Academy of Sciences
Łukasiewicz Research Network – Institute of Microelectronics and Photonics
DACPOL Ltd.
INWEBIT Ltd.
Aim of the project
The main goal of the EnerGaN proposal is to implement all necessary elements of a vertically integrated technological chain that will start in Poland: the production of energy-efficient Intelligent Energy Banks (IEB). The IEB will be based on energy flow control systems with efficient, high-energy-density, miniaturized converters supplied with artificial intelligence, allowing autonomous charge/discharge decision-making.
For IEB, vertical transistor technology based on gallium nitride (GaN) will be developed and implemented. Due to its outstanding merits, GaN is an optimum semiconductor for high-power, high-frequency transistors for energy distribution and transfer systems. Systems based on GaN devices will be energy-saving, reliable, and miniaturized in comparison to existing Si-based solutions.
Short description of the problem addressed by this project
The final product planned for development – the Intelligent Energy Bank – is a novelty on the Polish and foreign markets. Currently, no power banks are manufactured relying entirely on transistors based on the semiconductor in the form of gallium nitride (GaN on GaN). In addition, our banks will be equipped with innovative artificial intelligence algorithms to manage them. Due to the lack of energy banks based on GaN transistors, the main competition for the product being developed are energy banks based on silicon or silicon carbide (SiC) transistors, with the same basic functionality as energy storage using electrochemical batteries (Li-Ion or others). In this case, using new materials directly translates into one of the essential features used to compare competitive products: energy efficiency. A significant reduction in energy losses resulting from the current energy conversion will be achieved thanks to the use of gallium nitride as a semiconductor and the production of super-efficient transistor modules on GaN substrates.
Main results and achievements
The EnerGaN consortium has significantly developed all elements of vertically integrated technology chain for relevant transistors and energy storage intelligent control systems: single crystalline GaN substrates and epitaxial layer structures (IHPP PAS), semiconductor devices processing (Łukasiewicz-IMiF), high power control (DACPOL Ltd.), as well as algorithms and software for artificial intelligence systems (INWEBIT Ltd.)
Technologies for individual construction elements of GaN-on-GaN diodes and power transistors have been developed at Łukasiewicz-IMiF, in particular low-resistance ohmic contacts for N-face and Ga-face n-GaN and p-GaN, etching processes of trench structures, gate dielectric layers for GaN MOSFETs as well as junction termination structures. These were incorporated into the developed process flow of vertical power devices. Multi-gate transistors with hexagonal topology comprised 182 cells with a total gate length of 11.1 mm and current efficiency above 1A. High-quality p-i-n GaN diodes were made with a breakdown voltage close to 2kV and a record-low resistance value.
A prototype of an energy bank was made and tested along the photovoltaic installation with a total peak power of 250 kW, and all design parameters and full technical readiness of the developed energy bank demonstrator with reference converters in SiC technology.
Conclusion
The implementation of the project significantly influenced the development of key competencies in the field of all elements needed to produce intelligent energy banks based on GaN-on-GaN semiconductor elements and supported by artificial intelligence algorithms that facilitate autonomous decisions on charging and discharging. Particularly significant development was conducted in the field of GaN-on-GaN structure technology, consolidating the position of Polish research centers as one of the leaders of this technology in the world.
Acknowledgments
This work was supported by The National Centre for Research and Development under Agreement nr TECHMATSTRATEG-III/0003/2019 for the project “Complete vertically integrated technological chain for vertical GaN-on-GaN power electronics: from GaN substrate to the Intelligent Energy Bank.”
