Strained quantum well valence-band structure and optimal parameters for AlGaAs-InGaAs-AlGaAs p-channel field-effect transistors

Using the model of an infinite well we have performed detailed calculations of the valence-band structure and for the first time obtained analytic expressions for wave functions in a strained quantum well. In-plane effective masses and energy separations are calculated for different thicknesses of InGaAs wells and In mole fractions in the range of 0 to 0.50. Based on the calculations we estimate the optimal thickness of the well and In mole fraction for which the energy separation between the lowest two subbands has a maximum and the InGaAs layer is stable with respect to misfit dislocations. The results provide useful guidelines for the optimization of strained p-channel field-effect transistors.