The fabrication of high-power semiconductors has become easier, as the electrical engineers at the University of Illinois recently added beta-gallium oxide, the field’s trending material, to their armory.
Beta-gallium oxide has the ability to change power more efficiently and quickly as compared to the current semiconductor materials, such as gallium nitride and silicon. The researchers also stated that the compound can be easily procured. The results of the study have been published in the journal, ACS Nano.
The engineers took advantage of a method, known as metal-assisted chemical etching or MacEtch, in which a semiconductor is etched into 3D fin structures using a chemical solution.
Even though flat transistors have become compact, the issues associated with this type remain unresolved, and to counter those, scientists are now inclining toward vertical transistors. The fins improve the surface area on a chip, thereby enabling more transistors or current. They can therefore deal with more power and simultaneously maintain the footprint of the chip.
The research team further stated that the MacEtch method, which uses beta-gallium oxide, is more advanced than the “dry” etching method as it doesn’t damage the delicate semiconductor surfaces.
“Gallium oxide has a wider energy gap in which electrons can move freely. This energy gap needs to be large for electronics with higher voltages and even low-voltage ones with fast switching frequencies, so we are very interested in this type of material for use in modern devices. However, it has a more complex crystal structure than pure silicon, making it difficult to control during the etching process,” mentioned Professor Xiuling Li of the University of Illinois.
She further added, “Right now, the etching process is very slow,” she stated. “Because of the slow rate and the complex crystal structure of the material, the 3D fins produced are not perfectly vertical, and vertical fins are ideal for efficient use of power.” The scientist further stated that more studies are required to find solutions to problems regarding low thermal conductivity and slow etch rate to help in the development of high-performance beta-gallium oxide devices.