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MOSFET Lombardi Low Field Mobility Model

Lombardi's mobility model accounts for the effect of the transverse electric on mobility in a MOSFET device. Lombardi's formulation adds terms for surface acoustic phonon ( tex2html_wrap_inline2813 ) and surface roughness scattering ( tex2html_wrap_inline2815 ) to the bulk mobility ( tex2html_wrap_inline2817 ) using a Matthiesen-like rule:


The bulk mobility ( tex2html_wrap_inline2817 ) can be from a variety of formulations, typically the Arora model in Prophet. Lombardi gives the following forms for tex2html_wrap_inline2813 and tex2html_wrap_inline2815 :



Table 3 summarizes the Prophet parameter names and default values for the Lombardi mobility model. Conventional usage expresses mobility in units of tex2html_wrap_inline2775 ; however, Prophet uses units of tex2html_wrap_inline2777 , so the numerical values of the mobility parameters appear to be tex2html_wrap_inline2779 larger than usual.

Table 3: Lombardi Mobility Model Parameters and Default Values

Prophet Development
Mon Jul 1 14:45:00 PDT 2002