Abstract: A semiconductor device includes: a semiconductor part including a first semiconductor layer and a second semiconductor layer in contact with the first semiconductor layer; a first electrode electrically connected to the first semiconductor layer on a front surface side or a back surface side of the semiconductor part; a second electrode electrically connected to the second semiconductor layer on the front surface side of the semiconductor part; a gate electrode; an interlayer insulating film electrically insulating the gate electrode and the second electrode on the front surface side of the semiconductor part; and a third semiconductor layer having: a first region in contact with the second semiconductor layer and the second electrode on the front surface side of the semiconductor part; and a second region provided between the interlayer insulating film and the second electrode in a second direction perpendicular to a first direction.

Abstract: A distributing system 20, comprising: connection lines 3 to two ends of each of which connector plugs 9 with memory function unit 10 capable of untouchably performing, from the outside thereof, writing-in operation and reading-out operation of identification information of the same connector plugs are respectively connected; plug boards 6 mounted on the distributing system; adapters or receptacles 7, mounted separately on the plug boards and connected respectively to communication lines, for coupling to each of the connector plugs; antennas 11 positioned at the neighborhood of each of the adapters or receptacles for untouchably writing-in operation into and reading-out operation of the address information from the memory function unit when each of the connector plugs is coupled to desired one of the adapters or receptacles; and a data processing and display device 17,18, connected to the antennas, comprising memory means for storing a wiring table indicative of desired mutual relationship between said address