Abstract: Described is an improved NPN equivalent structure with a breakdown voltage higher than the intrinsic breakdown voltage of the NPN transistor utilizing a complementary PNP transistor and a JFET transistor with the gate connected to ground, the drain connected to the base of the PNP and the source connected to the collectors of the complementary pair. An integrated form of the structure is particularly advantageous and the equivalent NPN transistor is substantially exempt from Early effect and has improved output current capacity.

Abstract: Described is an integrated semiconductor structure for the protection from electrical discharges of electrostatic origin of particularly sensitive components of an integrated circuit. The structure is almost entirely formed directly underneath a particular input pad thus requiring a minimum useful area and is characterized by very high damaging voltage and speed of intervention because of the extremely low series resistance of the two zener junctions constituting the structure.

Abstract: This method of making an implanted resistor comprises the steps of implanting the resistor with ordinary techniques and deposition over the implanted resistor of a polysilicon layer having a set thickness and fully covering the resistor. Thus, the resulting resistor is unaffected by any subsequent thermal treatments and its value remains constant irrespective of any high potential metal layers or connections crossing it. The method affords in particular resistive values of the order of 1 kOhms/square.

Abstract: A buried-resistance semiconductor device is constructed by forming a P-type monocrystalline silicon substrate on which an epitaxial layer of silicon doped with type N impurities is grown, a portion of the epitaxial layer being insulated by a P-type insulating region extending from the substrate to the surface of the epitaxial layer. Two suitably-spaced terminals are secured to the surface of the epitaxial layer in the area bounded by the insulating region. Two separation regions extending into the surface layer are formed in the part of the epitaxial layer between the terminals, and a buried region extends from the substrate between the separation regions without being in contact with them. The three regions are of P-type material, and have an elongated shape and are bounded at the ends by the insulating region.

Abstract: This controlled electronic switching device for the suppression of transients can change over from a non-conductive state to a conductive state at lower triggering current levels than conventional devices while retaining unaltered its response characteristics to variations in the voltage applied thereacross. The device comprises a main switch which is triggered by a parallel-connected auxiliary switch having smaller junction areas and a higher capacitive current shunt resistance (resistance between base and emitter) than the main switch, thereby it turns on at lower control currents from the gate electrode for a given response to voltage variations.