Improved microwave Hall effect measurements method

Measurements of the microwave Hall mobility of semiconductors have been performed by an improved contactless method at 20 GHz by using a bimodal cavity resonator and a two-channel vector network analyzer. Data analysis was performed by using generalized expressions for the mobility, taking into account different coupling values on the two ports and a nonlinear response due to high magnetic fields in samples with mobility from thousands of cm2/V s. For several samples, Hall microwave and dc measurements have been compared, confirming the reliability of the proposed method; the characterization of bulk n-ZnSe and modulation-doped n-Al0.33Ga0.67As/GaAs two-dimensional electron gas samples is in particular presented. This method appears particularly suitable for the experimental determination of magnetotransport properties of semiconductor materials, especially when good electric contacts are difficult to be realized.