Energy spectrum of backscattered electrons excited by a field emission scanning tunneling microscope with a build-up w111x-oriented W tip

A field emission scanning tunneling microscope STM.combined with an electron energy analyzer was developed to acquire energy spectra of electrons backscattered from a sample surface impinged by a primary electron beam, which is field-emitted from an STM tip of build-up w111x-oriented W. Since the electron beam is field-emitted from the most protruding point of thew111xapex with a low work function and a sharp corner, the electron impinged area can be imaged with the STM by approaching the build-up W tip to the sample. Electron energy loss and Auger electron spectra were obtained for Si 111.; an elastic backscattering peak, bulk plasmon loss peaks and a Si LVV Auger peak were detected. The origin of anomalous broad inelastic peaks was also discussed. q1999 Elsevier Science B.V. All rights reserved