Irreversible semiconductor switching element and semiconductor memory device utilizing the same
AssigneeNippon Telegraph & Telephone Public Corporation
InventorsMasafumi Tanimoto, Takashi Watanabe, Nobuaki Ieda, Junichi Murota
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Abstract
A semiconductor switching element comprised by a high resistivity polycrystalline silicon resistor whose resistance irreversibly decreases to a small value at a threshold voltage upon the voltage across the resistor reaching the threshold voltage. A semiconductor memory device is constituted by using the switching element as a memory cell and a semiconductor gate element for controlling the current flowing through the semiconductor switching element.
Claims17
A semiconductor switching element having an irreversible conductivity characteristic comprising a high resistivity thin polycrystalline silicon resistor layer having a resistivity of from 10.sup.4 to 10.sup.7 ohm-cm and a thickness of from 0.15 to 1 microns and terminal electrode means formed on opposite planar surfaces on said thin silicon resistor layer for applying operating voltage across the thickness of said thin polycrystalline silicon resistor layer and establishing a current path therethrough, the resistance of said thin polycrystalline silicon resistor layer switching irreversibly in a non-destructive manner to a lower value upon the magnitude of an applied operating voltage exceeding a predesigned threshold voltage value of the order from 8 to 25 volts at which the resistance of the resistor layer switches irreversibly to the lower value to thereby provide a manyfold increase of at least an order of magnitude in the current flowing through the thin polycrystalline silicon resistor layer upon the application of a read voltage less than said threshold voltage value across the terminal electrode of the thin polycrystalline silicon resistor layer.
Dependencies are inferred from the claim text.