In conventional ETM circuit structures a pin connector in which the pin is etched from the ETM substrate and the mating cavity is etched from the ETM substrate to be mated. The connector utilizes the subtractive ETM structure processing to define any one of several pin-cavity configurations. The pin serves as an anchor with the metallurgical bonds with solder in the cavity that forms on the copper surfaces of the ETM circuit structure to give good mechanical strength to the connection. In particular four different configurations of interconnections are shown and described.