ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
We present a quantitative approach to the potential fluctuation model we have previously developed in disordered semiconductors. MOSFET (metal-oxide-semiconductor field-effect transistors) were irradiated along lines parallel (L structures) or perpendicular (T structures) to the drain-source direction, using a 20-keV scanned e-beam. Thus, in the inversion regime, the surface potential ψs was periodically modulated, thereby strongly modifying the conduction processes. Hall measurements were performed as a function of temperature and gate voltage at various irradiation doses and for different periods. Conduction in L structures was influenced by lateral potential barrier scattering, whereas it was barrier controlled in T structures. The experimental results are interpreted by a simple model of energetic distribution of both carrier density n(E) and mobility μ(E), based on the existence of a conduction threshold. When barriers were wide in T structures, Hall measurements showed that part of the carriers did not participate in conductivity in the weak inversion regime, while mixed conduction processes occurred when barriers were narrow. In contrast, all the carriers conducted in the strong inversion regime, and only the mobility was perturbed. Thus the field effect in irradiated MOSFET was used to correlate the Hall carrier density with the conduction threshold energy.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.343697
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