Apparatus and Method for Non-Contact Surface Voltage Probing by Scanning Photoelectron Emission.
Patent, Filed 11 Feb 91, patented 22 Sept 92,
DEPARTMENT OF THE NAVY WASHINGTON DC
Pagination or Media Count:
An apparatus and method for non-contact sensing electrical potentials of selected regions on the surface of a sample are provided. A typical sample is an integrated circuit, electronic device, or semiconductor material. The sample is positioned within a vacuum chamber and irradiated with an ultraviolet light beam so that the material emits electrons by the photoelectric effect. The electrons have kinetic energies which are variable according to the electrical potential of the surface of the material. Emitted electrons having kinetic energies within a predetermined range are selected by an electron energy analyzer. An electron detector receives the selected electrons and produces electrical signals corresponding to the energies of said selected electrons. In another embodiment of the invention, a modulated light beam other than the ultraviolet light probe beam irradiates the material in order to produce time varying modulation of the photoelectron energy spectrum.
- ELECTRON ENERGY
- INTEGRATED CIRCUITS
- PHOTOELECTRIC EFFECT
- VACUUM CHAMBERS
- ELECTRICAL PROPERTIES
- ULTRAVIOLET EQUIPMENT
- LIGHT SOURCES
- Nuclear Physics and Elementary Particle Physics
- Electricity and Magnetism
- Electrical and Electronic Equipment