Growth and characterization of ultrahigh vacuum/chemical vapor deposition SiGe epitaxial layers on bulk single-crystal SiGe and Si substrates

Abstract

Momentum space tomographic imaging of photoelectrons AbstractWe apply tomography, a general method for reconstructing 3D distributions from multiple projections, to reconstruct the momentum distribution of electrons produced via strong field photoionization. The projections are obtained by rotating the electron distribution via the polarization of the ionizing laser beam and recording a momentum spectrum at each angle with a 2D velocity map imaging spectrometer. For linearly polarized light, the tomographic reconstruction agrees with the distribution obtained using an Abel inversion. Electron tomography, which can be applied to any polarization, will simplify the technology of electron imaging. The method can be directly generalized to other charged particles.

A comparative study on the growth of germanium–silicon single crystals grown by the vertical Bridgman and axial heat processing techniques

“…Traditionally, MOS transistors are built on bulk Si substrates. However, recent studies [6][7][8] have shown that strained Si epilayers grown on a relaxed Ge-Si substrate can significantly increase the dopant mobility in Si and so the operating speed and frequency of Si devices. In fact, these Ge-Si substrates are virtual substrates in the sense that they are grown as epilayers on Si substrates.…”

“…Bulk Ge-Si substrates stand as a strong substitute for virtual Ge-Si substrates. Recently, there have been studies [8][9][10] demonstrating that Ge-Si substrates grown using the bulk crystal growth techniques may have several advantages over the virtual substrates. In addition, compositionally graded bulk grown Ge-Si alloys have been successfully used in X-ray, g-ray, and neutron-diffraction optics [11,12].…”