APPLICATION OF EFFECTIVE-MEDIUM THEORY TO INVERSION LAYERS

Two-dimensional effective-medium theory is applied to the macroscopic-inhomogeneity model for transport in inversion layers near the threshold of conduction. The predicted behaviour resembles that which has been observed provided that reported Hall measurements have been made at carrier concentrations above the percolation threshold. The theory predicts a dramatic change in behaviour below the percolation threshold and extension of Hall measurements to lower carrier concentrations would provide an acid test of the validity of the model.