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AssigneeU.S. Philips Corporation
InventorsJohn Martin Shannon, John Ernest Ralph, Pieter Schagen
Estimating the term…
An electronic solid state device comprising a layer in which the electrical conductivity is controlled by a plurality of isolated discrete regions distributed within the bulk of the layer and forming potential barriers with semi conductor material of the layer surrounding the discrete regions. Electrical charge is stored in the layer by the discrete regions and the charging is obtained by the application of a potential pulse across the discrete regions. In a preferred operational mode the charging potential is applied such that current conduction paths in the layer are blocked by the depletion regions associated with the potential barrier for applied interrogation potentials across the regions of substantially smaller magnitude than the charging pulse. The device may consist of an imaging device having high charges gain and particular embodiments described consist of an image intensifier, an imaging active photocathode and a target plate of a vidicon camera tube.
A solid state device comprising a bulk semiconductor layer having distributed within a plurality of isolated discrete regions each forming a potential barrier with the semiconductor bulk, said discrete regions being embedded within and surrounded by the bulk semiconductor and being at floating potential, electrode means coupled to the layer, a source of charging potential, means for applying a potential pulse derived from the charging source by means of the electrode means across a portion of said layer for charging the discrete regions therein to reverse bias their barriers producing depletion zones surrounding the discrete regions, the discrete regions and potential barriers thereof being of a configuration and being distributed within the layer such that following application of a charging pulse the discrete regions remain sufficiently charged to support depletion zones in the bulk semiconductor that cause a condition of low electrical conduction through the layer portion when an interrogating voltage is applied thereto, a source of interrogating voltage, and means for interrogating the charge condition of the layer portion including means for applying a voltage derived from the interrogating source by means of the electrode means across said portion of said layer.
Dependencies are inferred from the claim text.