Reducing the effect of polar optical phonon scattering to modify electrical properties

In a heterojunction, electrical carriers are confined in the 2DEG. In high temperatures the mobility of electrical carriers is affected extremely by polar optical phonons (mu_po). mu_po relates to the frequency of optical modes and consequently to the interatomic force. By using a strain in the heterojunction interface the quantity of an interatomic force is increased. Finally, the frequency of optical modes and consequently the mobility of 2DEG will be enhanced in the room temperature. For this focal we used the modified heterostructure AlGaAs/GaSb/GaAs. GaSb has a lattice constant greater than the GaAs and has been sandwiched between two AlGaAs and GaAs layers as a strained layer. The thickness of the strained layer GaSb, has been taken about 30 Aringring to avoid creating misfit dislocations in the heterointerface.