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Anvil Semiconductors Limited
Anvil Semiconductors has developed a
unique proprietary technology which, by
growing thin layers of silicon carbide SiC
on silicon wafers, rather than using ex-
pensive bulk SiC, enables wafer costs to
be reduced by a factor of 20 and prom-
ises to deliver the advantages of SiC de-
vices for the cost of conventional silicon
ones. The proprietary process overcomes
the critical problems of mismatches in
lattice parameter and thermal coefficient
of expansion between the two materials
and can be readily migrated onto 150mm
diameter wafers – and potentially
beyond.
Another area of cost saving compared to
conventional SiC technology comes from
the processing of the active device. The
cubic form of SiC (3C-SiC) grown on sili-
con is much easier to process than the
hexagonal form of the material (4H-SiC)
which is produced in bulk crystals. Indeed
3C-SiC can be processed in a convention-
al silicon CMOS line with the addition of
one high temperature furnace.
Anvil is using third party facilities to pro-
duce production, device quality 3C-SiC on
100mm diameter silicon wafers with layer
thicknesses that permit the fabrication of
vertical 1200V power devices. These are
being used to develop vertical 650V and
1200V Schottky Barrier Diodes (SBDs) and
MOSFETs in 3C-SiC capable of current
densities of at least 500A/cm
2
. The SBDs
produced to date show ideal character-
istics, no silicon/SiC interface effects and
excellent yields.
Anvil Semiconductors has offices in Coven-
try and Cambridge and has a small expe-
rienced team and an extensive network of
Industrial and Academic partners to develop
unique silicon carbide power device.
SiC offers many superior properties over
silicon:
•
SiC can sustain higher voltages reduc-
ing system complexity and cost whilst
improving system reliability.
•
SiC can carry higher currents with low-
er parasitic capacitances.
•
SiC has a higher thermal conductivity
and can operate at temperatures up to
400 °C (cf silicon 150 °C) reducing the
cooling costs and complexity of appli-
cations such as hybrid vehicles.
•
SiC is able to switch ten times fast-
er allowing the use of smaller capaci-
tors and inductors producing cheaper,
smaller and more efficient systems.
Advantages of
Silicon Carbide
