Abstract
Differential-capacitance measurements have been performed on p-type GaP in order to determine its flatband potential in buffered electrolytic solutions at various pH. The reproducibility of the flatband-potential determination is greatly improved by chemical etching of the semiconductor surface. The slope of the flatband-potential–vs–pH curve is that predicted by the Nernst equation. Deriving the acceptor concentration is hampered by the unreliable measurement of the effective area of the electrode which is in contact with the electrolyte.