DELAMINATIONS OF THIN-LAYERS BY HIGH-DOSE HYDROGEN-ION IMPLANTATION IN SILICON - FORMATION OF THIN SILICON-ON-INSULATOR SILICON LAYERS

The delamination of a thin layer from a Si wafer by high dose H+ impla ntation has been studied. This process is applicable to the manufactur e of Si on insulator wafers. Hydrogen ions are implanted into (100) p- Si through a 100 nm thick oxide layer at 100 keV with doses of 1.0 x 1 0(16) and 1.0 x 10(17) ion/cm(2). The implanted layer is measured by 1 .5 MeV He+ Rutherford backscattering spectrometry aligned spectra and by cross-sectional transmission electron microscopy after annealing. W ith annealing at 600 degrees C, delamination of the Si layer: which oc curred parallel to the surface, could be observed clearly at a depth o f 0.85 mu m for a dose of 1.0 x 10(17) ion/cm(2). The gap of the split Si layer is 20 similar to 50 nm wide. The roughness of the split laye r surface is 7.5 nm. Point defects at the split layer surface decrease d with annealing at high temperatures.