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 $\mu$ in the QW based field effect transistor (FET). A cubic double QW (CD-QW) structure made of $Al_{x}Ga_{1-x}As$ alloy is taken whose side barriers are Si $\delta$ -doped. We consider impurity $(imp-)$ and alloy $(al-)$ scatterings to calculate $\mu$. Additional interface roughness $(ir-)$ scattering is taken for square double QW (SD-QW). Mostly $\mu$ is controlled by $imp-$ scatterings because of the reduced effect of $al-$ disorder. It is gratifying to show that in CD-QW enhanced $\mu$ is obtained as compared to the conventional SD-QW structure. Our analysis will be helpful for improving the channel conductivity in QW based FETs.