Integrated circuit layers to be stacked on top of each other are formed with a plurality of inspection rectifier device units, respectively. The inspection rectifier device units including rectifier devices are connected between a plurality of connection terminals and a positive power supply lead and a grounding lead and emit light in response to a current. After electrically connecting the plurality of connection terminals to each other, a bias voltage is applied between the positive power supply lead and the grounding lead, and the connection state between the connection terminals is inspected according to a light emission of the inspection rectifier device unit. This makes it possible to inspect, in a short time every time a layer is stacked, whether or not an interlayer connection failure exists in a semiconductor integrated circuit device constructed by stacking a plurality of integrated circuit layers in their thickness direction.