The sensing mechanism of resistive gas sensors based on metal oxide semiconductors is ascribed to variations of majority carrier
surface concentration under the influence of adsorbed substances .
The [TDD.sub.CGB] is fixed to [10.sup.6] [cm.sup.-2] although this has no influence on the performance of the device because transport is a majority carrier
Baskys, "The model of the p-n junction depletion region v-i characteristic considering the dependence of concentration of majority carriers
on voltage", in Proc.
Since saturation velocity decreases with increasing temperature in a majority carrier
device, the SIT channel is thermally stable.
Being a true metal semiconductor -- a majority carrier
device (also called "wide-bandgap" semiconductor) -- the SiC diode physical structure is quite different than that of the widely used P-N silicon junction devices which are minority carrier devices.
In addition, reverse conduction during the dead-time is by majority carriers
only, resulting in zero stored charge.
Since majority carriers
are asymptomatic they pose a real threat to health personnel we well as other patients.
The total current I, starting the flow from the anode region 1 p and reaching the cathode region [n.sub.2] is influenced by the integral coefficient of the majority carriers
(holes for pnpn structures and electrons for the npnp structures) injection of junction J1, by the integral transfer coefficient of the minority carriers (holes for pnpn structures and electrons for the npnp structures) through wide base, and by the avalanche multiplication of charge carriers, taking place in the collector junction at relatively high forward voltages.
A strong DC bias causes majority carriers
in the substrate to accumulate near the insulator interface.
While the same must be true for bipolar junction transistors, the effect is mitigated by the bipolar phenomenon of conductivity modulation, whereby operation in the saturation region causes the injection of minority carriers into the collector region, resulting in a commensurate injection of majority carriers
to preserve charge neutrality.
This relative minimum occurs because of the reduction of minority carrier (electron) scattering from plasmons associated with majority carriers
(holes) and because of the removal of majority carriers
(holes) from scattering the minority carriers (electrons) due to the Pauli exclusion principle for the majority carriers