In this paper, we apply a novel contactless method that we study to investigate the physical properties of the semiconductor materials. This method is based upon the measurement of the surface electron beam exciting potential (SEBEP) on the sample surface. Its advantages include: no direct sample contact or connection needed that is unlike the electron beam inducing current (EBIC) method; no potential barrier required from the measurement.

Electron probe irradiation can cause bending of the energy bands, variation of carriers and excitation of surface potential. The excited surface potential generates the SEBEP signal that can be detected by a SEBEP detector. It is necessary to emphasize that the electron beam can charge the surface that is under the oxide layer when it passes through the sample surface oxide layer.

It is known that the diffusion length L and the average lifetime τ of the non-equilibrium carries can be measured by other methods such as the cathodoluminescent method and the contacting method..