Small area photoemission and photoabsorption measurements using a photoelectron microscope

A technique is demonstrated for measuring photoemission and photoabsorption spectra from areas as small as 20 µm in diameter. A magnetic projection photoelectron microscope relying on the electron imaging and magnifying properties of a diverging magnetic field is described. This photoelectron microscope is of the type originally conceived by the Turner group at Oxford University. XANES spectra from 20 µm diameter regions of high Tc superconductors and from 40 µm diameter regions at the bottom of vias etched through photoresist are presented. Small area UPS spectra of In deposited locally on GaAs are also shown. Potential exists to measure photoabsorption spectra from areas on the order of one micron square.