Structural and electrical properties of Ge(111) films grown on Si(111) substrates and application to Ge(111)-on-Insulator

Structural and electrical properties of a Ge(111) layer directly grown on a Si(111) substrate are studied. Via optimized two-step growth manner, we forma high-quality relaxed Ge layer, where strain-relieving dislocations are confined close to a Ge/Si interface. Consequently, a density of holes, which unintentionally come from crystal defects, is highly suppressed below 4 x 10(16) cm(-3), which leads to significantly high hole Hallmobility exceeding 1500 cm(2)/Vs at room temperature. By layer transfer of the grown Ge layer, we also fabricate a Ge(111)-on-Insulator, which is a promising template for high-performance Ge-based electronic and photonic devices. (C) 2015 Elsevier B.V. All rights reserved.