The delamination of thin silicon layers by ion implantation and annealing has been studied in H+ implanted silicon layers. Hydrogen ions are implanted into a (100) p-silicon layer through a 100 nm thick oxide layer at 100 keV with different doses ranging from 1.0 x 10(16) to 1.0 x 10(17) ion/cm(2). Delamination of thin silicon layers was clearly observed in cross-sectional scanning electron microscope photographs at doses above 5.0 x 10(16) ion/cm(2). The delamination occurs al 485 degrees C with 10 min annealing for an implantation at 5.0 x 10(16) ion/cm(2). This temperature, however, can be reduced to 425 and 400 degrees C by increasing annealing time to 60 and 120 min, respectively Delamination is closely related to the formation of H-Si defect bonds and the release of a hydrogen atom from these bonds in the hydrogen ion implanted Si layer. Temperature variation of the intensity in the hydrogen desorption shows two intensity peaks al 450 and 650 degrees C.