Viscoelasticity of dense suspensions of thermosensitive microgel mixtures undergoing colloidal gelation

Viscoelasticity of dense suspensions of thermosensitive microgel mixtures exhibits characteristic temperature-dependence resulting from colloidal gelation.

Scattering of Free Carriers by Oxide Precipitates in Czochralski-Grown Silicon

Annealing of oxygen-rich Czochralski silicon at temperatures between 700°C and 1000°C introduces a new scattering mechanism which correlates very well with the presence of oxide precipitates. In lightly doped crystals (n,p ∼1015cm−3) this mechanism becomes dominant at T<170°C, and it determines to a large extent the value of the electron (hole) mobilities. The effect vanishes upon annealing at 1300°C; such heat treatment causes the dissolution of oxide precipitates. The new component mobility related to precipitates was found to exhibit a characteristic temperature dependence μ ∝ T0.5. This dependence was explained in terms of scattering of free carriers by spacially slowly varying potential associated with oxide precipitates of varying size.