Large-area N-P-N power transistors

Experimental large area N-P-N power transistors having greatly improved performance at high currents will be discussed. In an alloyed construction collector-to-base current ratios as high as 1000 at 1 ampere have been obtained. Another construction utilizing diffusion and alloy techniques will also be described. The advantages of this transistor over the conventional alloy type, such as higher collector dissipation, flatter junctions and closer spacings between junctions will be discussed. This transistor has collector-to-base current ratios of several hundred at 1 ampere and collector breakdown voltages of 70 to 150 volts.