There are strong distribution effects in very small MOSFET’s.Their some characteristics should be described by twodimensional models.In this paper

twodimensional analytic distribution models of drain and substrate currents are built by use of flow function equations on y crosssection.The models are dependent on vertical electrical field Ex（y） and horizontal electrical field Ey（y）

and include much more physical processes

and show basically the exact distributions of the current densities.These two analytic models can be used in studying the characteristics dependent on current lines

especially

in the field of gate current distribution modeling in MOS’s hotcarrier reliability electronics.Using models of Ex（y）

Ey（y）

IDS and so on in deep submicron MOSFET’s

the distribution models in the paper can be applied in these devices.