Abstract: A semiconductor device comprising a semiconductor body portion having a shallow surface layer which is higher doped than the bulk of the semiconductor body portion, and a metal electrode on this layer and forming a Schottky barrier with the body portion. The layer serves to control the effective height of the barrier. The depth of the layer is such that the layer is substantially depleted of charge carriers in the zero bias condition whereby the slope of the reverse current-voltage characteristic of the barrier below break-down is determined by the doping of the bulk of the body portion substantially independently of the presence of the layer. Depending on the conductivity type of the layer relative to the bulk, the barrier can be higher or lower than that which would be formed in the absence of this layer. By providing the layer by implantation good control of the doping and hence of the barrier height can be obtained. Applicable to both discrete Schottky diodes and Schottky barriers in integrated circuits.

Abstract: A semiconductor memory element comprising a semiconductor substrate and an insulating layer thereon, a charge storage element located on a portion of the insulating layer and separated from the semiconductor substrate, and first device means for injecting hot electrons from the semiconductor substrate into the insulating layer portion to write a first charge state on the charge storage element and second device means for injecting hot holes from the semiconductor substrate into the insulating layer portion to write a second charge state on the charge storage element.

Abstract: A semiconductor device comprising a semiconductor body portion having a shallow surface layer which is higher doped than the bulk of the semiconductor body portion, and a metal electrode on this layer and forming a Schottky barrier with the body portion. The layer serves to control the effective height of the barrier. The depth of the layer is such that the layer is substantially depleted of charge carriers in the zero bias condition whereby the slope of the reverse current-voltage characteristic of the barrier below break-down is determined by the doping of the bulk of the body portion substantially independently of the presence of the layer. Depending on the conductivity type of the layer relative to the bulk, the barrier can be higher or lower than that which would be formed in the absence of this layer. By providing the layer by implantation good control of the doping and hence of the barrier height can be obtained. Applicable to both discrete Schottky diodes and Schottky barriers in integrated circuits.

Abstract: A method for making an IGFET is described. The method utilizes impurity ion implantation into the surface channel to determine the conductivity thereof. The advantages include special impurity profiles providing improved performance, better control over important parameters such as threshold voltage, the manufacture of improved tetrodes, and the manufacture of improved ICs using for example N- and P-channel devices, and depletion and enhancement devices combined in a single chip.