الفهرس 
MOSFET StructuresOnly 14 pages are availabe for public view
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Abstract
In this thesis we suggested a new MOSFET device that is realized by
using the known MOSFET technology with a Graded Band Gap
channel (GBGC) in the longitudinal direction from the source to drain
with the greater band gap at the source side and the smaller one at the
drain side. This graded band gap can be achieved by implanting atoms
.---~--·· -- ...
of a material which has a smaller band gap energy than silicon like
Ge. The fractional ratio of the implanted atoms increases with the
position x towards the drain. This architectural feature of the graded
energy band along the channel has the following advantages; i)
inducing an internal electric field that accelerates the electrons faster
from the source to the drain. ii) reduction of the pot~ntial barrier of
the source-channel junction, and iii) overcoming most mobility
degradation mechanisms. The previous reasons make it possible to
have a GBGC MOSFET that is faster and has a higher cut-off
frequency than normal MOSFET.
Moreover the GBGC structure improves the noise figure, decreases
the high resistance hot zone which often exits besides the drain due to
a high conductivity beside the drain region and consequently;
.1 suppresses the possibility of thermal and carrier heating and hence the
.’.\ , probability of bulk and/or surface breakdown. A new circuit technique
has been introduced to simulate the GBGC MOSFET using SPICE.