EPITAXIAL SI-GE ETCH-STOP LAYERS WITH ETHYLENE DIAMINE PYROCATECHOL FOR BONDED AND ETCHBACK SILICON-ON-INSULATOR

The etch rate in ethylene diamine pyrocatechol of Si1-xGex (0.2 less-t han-or-equal-to x less-than-or-equal-to 0.3) etch stops grown by molec ular beam epitaxy was determined using Rutherford backscattering spect rometry. Etch rate selectivities as high as 390 were measured. Such et ch stops allow for higher bonding temperatures than those possible wit h currently used boron-based etch stops. Defect etching was used to de termine the maximal thickness of dislocation-free layers.