Abstract An experimental study of a reflection cavity scheme used to measure changes in the conductivity of semiconductor samples is presented. The germanium sample with associated microwave circuitry acts as a highly sensitive system where by in the null condition almost complete absorption occurs. Changes in conductivity from the null point will cause a sharp increase in reflected microwave power. This change in reflected power may be used to measure a change in conductivity, or in a device...

Abstract The reflections of microwaves from a low conductivity semiconductor, lossy, air space, metal arrangement have been studied. At any given frequency by selecting the thickness of the semiconductor, loss and the distance to the metal reflector, complete absorption of microwave energy can be obtained. It is shown that very small changes in semiconductor conductivity, semiconductory thickness, and distance to the metal reflector result in measureable reflected power. This technique will allow...