MOSFETs are scaled primarily due to increased packing density and speed. Due to scaling some drawbacks are found in conventional MOSFET. They are mobility degradation and surface scattering, velocity saturation in MOSFET, avalanche breakdown, hot electron effect, drain induced barrier lowering(DIBL), reduction of threshold voltage, punch through. These drawbacks are known as Short Channel Effect(SCE).The model of double halo dual material gate combines the advantages of both the channel engineering (halo) and the gate engineering techniques (dual-material gate) to effectively suppress the short-channel effects (SCEs). The model is derived using the pseudo-2D analysis by applying the Gauss's law to an elementary rectangular box in the channel depletion region, considering the surface potential variation with the channel depletion layer depth. Это и многое другое вы найдете в книге Remedies of Short Channel Effects in Conventional MOSFET (Swapnadip De,Debarati Das and Chandan Kumar Sarkar)