Electronic properties and phase basic solid state physics transitions in Si, ZnSe, and GaAs under pressure cycling up to 20-30 GPa in a high-pressure cell

Abstract

An automated high-pressure setup employing anvil-type cells is applied for investigation of phase transitions and electronic properties (the thermoelectric power (Seebeck effect), the electrical resistivity) of silicon, zinc selenide and gal lium arsenide under pressure cycling within the range of 0 - 20(30) GPa. The "correlation" dependencies of a pressure value of the semiconductor-metal transition in Czochralski- grown silicon (Cz-Si) on the concentrations of both carriers and residual interstitial oxygen are discussed. In all Si samples a decompression of the high-pressure metal phase produces the semimetal p-type phases: the rhombohedral r8 (Si-XII) and the body-centred cubic bc8 (Si-III) lattices. Re- pressurization cycles reveal two features in the semimetal phase, near 2 GPa and 5 GPa. The transitions into the metal phase at higher pressure resemble those in pristine silicon. For ZnSe and GaAs, it is found that decompression from the high-pressure phases (NaCl and Cmcm, respectively) can follow different paths, producing the zincblende, the cinnabar and the wurtzite lattices. Advantages of the characterization method are discussed, in comparison with both the traditional techniques (X-ray diffraction, Raman spectroscropy, etc.) and the more recent ones (such as nanoindentation). © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.