PURPOSE: To facilitate the recognition of an attaching direction by fixing a multilayer ceramic substrate provided with an external connection pin to a flange and by providing a display means to recognize a section having an attaching indication of a multilayer ceramic wiring board to one of pin covers which are attached to four corners of the flange.

CONSTITUTION: A chip carrier 2 is packaged on a multilayer ceramic wiring board 1 which is provided with a pin for external connection. The multilayer ceramic wiring board 1 is fixed to a flange 3. The four corners of the flange 3 are stepped, and a pin cover 6 is attached by a screw 4 thereto, respectively. A hole 6b is shaped below a pin cover 6a having an attaching indication of the multilayer ceramic wiring board 1 whereon the chip carrier 2 is packaged to identify from two directions. Thereby, a state of a pin can be observed from four directions and an attaching direction of a multilayer ceramic wiring board can be also recognized at a glance.