"Divide et impera" in detector technology

Three decades of achievements in epitaxial deposition of semiconductor layers on silicon form the basis for the present optoelectronic devices, such as semiconductor lasers and detectors. Actually, the strain induced by different lattice parameters and thermal expansion coefficients offers additional degrees of freedom for tailoring material properties, but often at the expense of dislocation generation, wafer bowing and cracks. Such drawbacks can be eliminated by growing, onto deeply patterned Si substrates, space filling arrays of high-quality strain-free Ge prisms up to tens of micrometers in height, while avoiding their merging. The method opens the way to applications requiring pixelated thick films, e.g. high-resolution radiation and particle imaging detectors, monolithically integrated onto CMOS platforms.