Ballistic electron emission microscopy using InAs tips

In this work, ballistic electron emission microscopy (BEEM) experiments with n-doped InAs tips are reported. Room temperature BEEM spectra obtained with InAs tips show a different spectral behavior compared to reference spectra measured with Au tips. The BEEM spectra were calculated with an extended Bell-Kaiser model for both Au and InAs tips. For InAs tips, excellent agreement between the measured and calculated spectra is obtained only if parallel momentum conservation is assumed both at the Au-GaAs interface and for the tunneling processes between the InAs tip and the Au film. At room temperature, however, tunneling via InAs surface states and scattering inside the Au film is found to dominate the spectral behavior of the BEEM spectra. © 1998 Springer-Verlag.