Saga Univ: Ultimate “Diamond Semiconductor” Developed: Applied to 6G Base Stations
-Output “the best in the world”-
Faculty of Science and Technology, Saga University:
Professor Makoto Kasuu:
Succeeded in “manufacturing the world’s highest output semiconductor parts using artificial diamond as a substrate”.
It is expected to be applied to “6G mobile base station equipment, etc.”
Aim for mass production within 5 years.
-Semiconductor using diamond-
According to Professor Kakazu, the mainstream of semiconductors is currently made of silicon.
Theoretically, diamond semiconductors are capable of high output and are also excellent in durability.
As the ultimate semiconductor, basic research has been underway for 20 years.
Diamond semiconductor, wall of practical use:
However, “conventionally, the size that can be manufactured is only 4 mm square”.
Not enough energy efficiency
A chemical reaction takes place inside
Because it is easy to deteriorate
Diamond semiconductors have not been put into practical use.
Improved performance of diamond semiconductors:
This time, the durability of diamond semiconductors has been dramatically improved.
“This time, changing the layer structure on the surface of the semiconductor, etc.”
Succeeded in “significantly reducing chemical reactions”.
Durability has improved dramatically.
The output power is about 22 times higher.
The size could be increased to a circular shape with a diameter of 25.4 mm.
Fields of application of diamond semiconductors:
“Utilization in fields where high quality is required, such as EVs and artificial satellites” is expected.
[Nishi-Nippon Shimbun News]
https://www.nishinippon.co.jp/item/n/730661/
New operating principle: Succeeded in manufacturing diamond semiconductor power device
-Diamond semiconductor with ultimate power semiconductor physical characteristics-
Large-diameter, high-purity diamond wafer crystal manufacturing technology (currently 1 inch)
Invented a device structure based on a new operating principle (patent pending)
World’s highest level 179 MW / cm2 high output power
Ideal for Beyond 5G mobile base stations and devices for electric vehicle power control
Reliability that can be used for a long time by replacing the vacuum tube even in outer space
Saga University Public Relations Office
https://www.saga-u.ac.jp/koho/press/2021042021534
Fabrication of diamond modulation-doped FETs by NO2 delta doping in an Al2O3 gate layer
Makoto Kasu1, Niloy Chandra Saha1, Toshiyuki Oishi1 and Seong-Woo Kim2
Published 20 April 2021 • © 2021 The Japan Society of Applied Physics Applied Physics Express, Volume 14, Number 5 Citation
Abstract
We demonstrated modulation doping
in diamond and fabricated diamond field-effect transistors (FETs) by NO2 p-type delta doping in an Al2O3 gate layer.
We confirmed modulation doping effects:
a spatial separation between the NO2 acceptors in the Al2O3 gate insulator and the hole channel on the diamond surface increased the hole mobility,
and the high hole sheet concentration was maintained till high temperatures.
The diamond FETs
showed maximum drain current density of −627 mA mm−1, and transconductance of 131 mS mm−1.The mobility
increased to 2465 cm2 V−1 centerdot s−1 near the threshold voltage, and the Baliga’s figure-of-merit was 179 MW cm−2.– IOPscience
https://iopscience.iop.org/article/10.35848/1882-0786/abf445