Abstract
Germanium (Ge) on silicon (Si) is an enabler of electronic and photonic convergence on the Si CMOS
platforms. Strained Ge has opened up a brand new fi eld of silicon photonic devices such as the longer
wavelength detection of photodetector and Ge lasers, i.e., indirect bandgap semiconductors. The
selective epitaxy of Ge has been studied because of its capability for limited area growth, low damage
during post-processing, and fewer threading dislocations in the Ge epilayers. The present paper
describes our recent discovery of the strain tunability of Ge by the selective growth mask.
