Abstract
Preliminary results using the new high resolution Wien filter spectrometer coupled to the scanning transmission electron microscope show that it is now possible to investigate atomic bonding, and both filled and empty electronic states in inhomogeneous materials with a 1 nm spatial resolution. We show three examples: (1) identification of a 5 nm layer of Si
2N
2O at a Si/Si
3N
4 interface using core-loss near-edge fine structure, (2) observation of effects due to changes in the conduction band density of states due to Si-Si bond disorder at the Si/SiO
2 interface, and (3) identification of a filled defect electronic state associated with a single misfit dislocation at a GaAs/GaInAs interface.