A fluid filled ampoule comprises an ampoule body having a top end, a bottom end and a sealed interior containing a liquid. The cable management member includes a pressing plate for binding the cables. The characteristic parameters of a curve-defining equation yk are calculated based on three measurements of output at times t, 2t and 4t. A tunneling member is mounted on the distal extremity of the tunneling shaft. In addition, a recovery operation for recovering a residual polarization amount is made to the memory cell. The decoupling region of the silicon substrate layer comprises an array of lamellas laterally spaced apart from each other by cavities.