Summary: | 碩士 === 國立成功大學 === 電機工程研究所 === 84 === In this thesis, we will discuss two kinds of InGaAs-GaAs
heterostructure graded doped-channel MIS-like FET. The main
advantage of graded doped-channel MIS-like FET''s is li- kely
doped-channel MIS-like FET''s(DMT''s). Comparing to DMT''s, it
better confinement in the channel, great feasibility for
improvement of device linearity and large logic swing noise
margin. We can moldulate the gate voltage swing range by gr-
unique properties and potential for high-speed,high-frequency,
hgih power and large input signal circuit applications. In
addition, we also discussion two kinds of multiple negative-
differential-resistance (MNDR) switching devices, based on
InGaAs-GaAs metal-insulator-semiconductor (MIS) li- ke
structure with a step-graded InGaAs quantum well. Due to its
capability of reducing circuit complexity, the MNDR concept has
become more interesting in the recent studied. The performance
of these two MNDR devices are different from the previously
reported NDR switching device and has not been fo- und for
other devices. The impressive MNDR behaviors are bel- believed
to be caused by the sequential accumulation process of InGaAs
subwells nd the successive barrier lowering and potential
redistribution effect. The interesting property provides
apromise of the studied structures to be a good condiate
switching device applications.
|