Demonstration of high-mobility electron and hole transport in a single InGaSb well for complementary circuits

Heterostructures consisting of an InGaSb quantum well situated between AlGaSb barriers were grown by molecular beam epitaxy. Calculations indicate a type-I band structure with substantial valence and conduction band offsets that can allow for the confinement of either electrons or holes in the InGaSb. Quantum wells with n-type conduction were achieved using modulation doping, with Te located in the barrier above the quantum well. A set of barrier layers was found which resulted in a sample with an In0.2Ga0.8Sb quantum well that exhibited an electron mobility of 3900 cm2/V s as grown. After removal of upper barrier layers including the Te by selective etching, the conductivity switched to p-type, with hole mobilities near 800 cm2/V s. This design could allow the integration of low-power n- and p-channel field-effect transistors for complementary logic applications.