Abstract: A thin film magnetic transducer having a magnetic circuit having nickel-iron layers which encloses a portion of first and second windings. The portions of each winding traversing the nickel-iron layers have conductor segments equal in number and separated from each other in parallel planes. The conductor segments of each winding have a center-to-center spacing different from the remaining winding selected to avoid contact with the transition regions of the nickel-iron layers and which results in a common inductance for each winding. The windings are joined at one end to form a center tapped winding.

Abstract: A method for fabricating bipolar semiconductor devices of large scale integration in which the formation of pipes, which result in shorts or leakages between two conductivity types of the semiconductor devices, is minimized. Prior to forming the emitters in the bipolar transistors, nucleation sites for crystallographic defects such as dislocation loops are formed in the base region near its surface. The emitters are then formed in base regions containing the nucleation sites and the sites are converted into electrically harmless dislocation loops during diffusion of the emitter impurity. Preferably, the nucleation sites are formed by implanting non-doping impurities, such as helium, neon, argon, krypton, xenon, silicon, and oxygen.

Abstract: A substantially square N-type impurity distribution profile in a silicon substrate produces much superior dc and ac characteristics in PN junction devices than can be expected from the usual phosphorus distribution profile. Such a square profile is obtained by diffusion of arsenic in the silicon substrate. The sharper impurity gradient allows a relatively low surface concentration to be used for the device. This lower surface concentration relieves precipitation and dislocation problems.