Electron Transport in AlxGa1-x As based Non-Square Double Quantum Well Field Effect Transistor Structure

We analyze the importance of non-square coupled double quantum well (QW) potential on electron transport property, e.g., electron mobility μ in the QW based field effect transistor (FET). A cubic double QW (CD-QW) structure made of Al_xGa_1-xAs alloy is taken whose side barriers are Si δ -doped. We consider impurity (imp-) and alloy (al-) scatterings to calculate μ. Additional interface roughness (ir-) scattering is taken for square double QW (SD-QW). Mostly μ is controlled by imp- scatterings because of the reduced effect of al- disorder. It is gratifying to show that in CD-QW enhanced μ is obtained as compared to the conventional SD-QW structure. Our analysis will be helpful for improving the channel conductivity in QW based FETs.