<s>
Modulation	B-Algorithm
doping	I-Algorithm
is	O
a	O
technique	O
for	O
fabricating	O
semiconductors	O
such	O
that	O
the	O
free	O
charge	O
carriers	O
are	O
spatially	O
separated	O
from	O
the	O
donors	O
.	O
</s>
<s>
Modulation	B-Algorithm
doping	I-Algorithm
was	O
conceived	O
in	O
Bell	O
Labs	O
in	O
1977	O
following	O
a	O
conversation	O
between	O
Horst	O
Störmer	O
and	O
Ray	O
Dingle	O
,	O
and	O
implemented	O
shortly	O
afterwards	O
by	O
Arthur	O
Gossard	O
.	O
</s>
<s>
Modulation-doped	O
transistors	B-Application
can	O
reach	O
high	O
electrical	O
mobilities	O
and	O
therefore	O
fast	O
operation	O
.	O
</s>
<s>
A	O
modulation-doped	O
field-effect	O
transistor	B-Application
is	O
known	O
as	O
a	O
MODFET	B-Algorithm
.	O
</s>
<s>
One	O
advantage	O
of	O
modulation	B-Algorithm
doping	I-Algorithm
is	O
that	O
the	O
charge	O
carriers	O
cannot	O
become	O
trapped	O
on	O
the	O
donors	O
even	O
at	O
the	O
lowest	O
temperatures	O
.	O
</s>
