Determination of Compensation Density by Hall and Mobility Analysis in Copper-Doped Germanium

The carrier concentration and mobility, as determined from the Hall effect, have been analyzed on a computer for a series of copper-doped-germanium samples. Both types of analysis gave good agreement in determining the density of compensating donors over the range of 4×{}10¹⁰ to 6×{}10¹⁵ cm^-3. This agreement is good evidence in support of the theory of ionized-impurity scattering. It was found that neutral-impurity-scattering theory had to be modified to account for the nonhydrogenic nature of the copper impurity center. The degeneracy of the copper acceptor was found to be four, in agreement with the effective-mass calculation.