Abstract: A method of providing less than one micron p-n junction regions for IGFET devices in which a high concentration of arsenic is implanted so that its peak lies near the surface of a semiconductor substrate. Phosphorus is also implanted with an energy to provide a maximum concentration below that of the arsenic and of a magnitude at least one order of magnitude less than that of arsenic. An oxidation/anneal step thermally diffuses the implanted ions to form a junction less than one micron in thickness.

Abstract: A method of making a transistor array includes forming a plurality of gate electrodes insulated from a semiconductor substrate having an impurity of a given conductivity, introducing a first impurity having a conductivity opposite to that of the given conductivity into a given region of the substrate which is adjacent to an edge of each of the gate electrodes, introducing a second impurity having the given conductivity into given regions adjacent to selected gate electrodes, the second impurity having a significantly higher diffusivity than that of the first impurity in the semiconductor substrate, and driving the second impurity along the surface of the semiconductor substrate to form in the substrate under each of the selected gate electrodes a region having a concentration of impurity of the given conductivity higher than that of the semiconductor substrate. The transistor array may be used, e.g.