Neutralization of Misfit Dislocations in Silicon-Germanium Devices Using Hydrogenation
Original Publication Date: 1989-Mar-01
Included in the Prior Art Database: 2005-Jan-27
A technique is described whereby the recombination effects of misfit dislocations (MFDs) are reduced in Si-Ge structures by using hydrogenation. The result is a reduction in leakage currents and an improved radiative recombination. In the fabrication of band gap engineered devices, such a hetero- junction bipolar transistors and modulation doped field-effect transistors, for direct gap and resonant tunnelling applications, the use of Si-Ge structures generally requires that the layers of the structure be strained. The strain causes MFDs to generate at the interfaces. They are usually initiated by process aberrations, such as impurities at the surface, temperature instabilities during growth, doping effects, edge effects, etc. The net result is two-fold: a reduction of strain and an increase in recombination.