Page 4 - april_032522.indd

TAP TIMES -4- APRIL 2022

Will GaN compete (from 3) Metals (conduc-
tors) have a low
bandgap or a
Theses compound semiconductors (such bandgap which
as InP, GaAs, SiC and GaN) fi nd wide ap- overlaps the con-
plications in high-performance RF/Micro- duction and va-
wave and optoelectronic devices. lance bands.

Superior electronic properties Wide bandgap
Their popularity is is due to their superior The term “Wide
electronic properties including high elec- Bandgap” (WBG)
tron mobility, high saturated velocity, and semiconductors
high thermal conductivity and the ability refers to bandgap
to work at higher breakdown voltages with voltages greater
low on resistance. than ~2eV.

This is a page from U.S.Patent
This is required for high-effi ciency power 2,524,035, “Three electrode el- Ultra-Wide Band-
converters in Electric Vehicles (EV), and ement utilizinging semiconduc-
tive materials” by Bardeen and gap (UWBG) semi-
Photo Voltaic (PV) Solar array (see Table Brattain. conductors, such
below). as high-Al-content AlGaN, diamond,
β-Ga203, boron nitrides with energy band-
gaps (>4 eV) are the fu-
ture spectrum for higher-
performance RF, TeraHertz
microwave devices and
and other high-power ap-
plications, including those
for extreme environments.

Wide bandgap, ultra-wide bandgap Conclusion
These properties are due to the material’s Over the last
bandgap. Using a simplifi ed view (right- few years, GaN
hand column) of solid-state materials with Technology
valence bands and conduction bands, we has started to
can compare the relative bandgap for in- gain adoption
sulators, semiconductors and conductors. and increased
Solid-state materials with valence- usage in high

The bandgap is the amount of energy (Eg) and conduction bands. frequency- and
needed to make electrons jump from the power applications after lagging SiC semi-
valence band through the “forbidden band” conductors’ adoption.
and enter the conduction band. When this
occurs, the material becomes more electri- This was due to the need to overcome
cally conductive. semiconductor manufacturing process-,
wafer size and cost restraints. However,
Insulators, like glass and ceramics, have we forecast explosive growth over the next
larger bandgaps on the order of ~6eV, few years as the GaN technology matures.
while semiconductors have a bandgap
range from ~0.7eV to ~6eV. See page 6