Power recitfier of the npnp type having recombination centers therein

Claim 1

A SEMICONDUCTOR POWER RECTIFIER, COMPRISING A SUBSTANTIALLY MONOCRYSTALLINE SEMICONDUCTOR BODY CONTAINING IN SUCCESSION A FIRST, A SECOND, A THIRD AND A FOURTH LAYER, WHICH LAYERS HAVE ALTERNATE RESPECTIVE TYPES OF CONDUCTIVITY, OF WHICH THE FIRST, SECOND AND THIRD LAYERS FORM A FIRST TRANSISTOR ELEMENT AND THE SECOND, THIRD AND FOURTH LAYERS FORM A SECOND TRANSISTOR ELEMENT, THE SECOND LAYER HAVING A DOPING CONCENTRATION OF SUBSTANTIALLY 10**17 CM.-3 IN A REGION ADJACENT TO THE FIRST LAYER AND OF SEVERAL POWERS OF 10 LOWER IN A REGION ADJACENT TO THE THIRD LAYER, AND THE THIRD LAYER HAVING THE LOWEST DOPING CONCENTRATION OF THE FOUR LAYERS, AND WHEREIN THE CURRENT GAIN OF THE FIRST TRANSISTOR ELEMENT IS SUBSTANTIALLY ZERO IN THE LOAD CURRENT DENSITY RANGE BELOW 10 MA./CM.2 AND BEGINS TO RISE STEEPLY IN A LOAD CURRENT DENSITY RANGE BETWEEN 10 AND 100 MA./CM.2, AND WHEREIN THE CURRENT GAIN OF THE SECOND TRANSISTOR ELEMENT HAS A VALUE BELOW UNITY AND IS SUBSTANTIALLY INDEPENDENT OF LOAD CURRENT IN THE LOAD CURRENT DENSITY RANGE BETWEEN 10 AND 100 MA./CM.2.