The invention relates to the manufacture of printed circuit boards having improved interlayer adhesion. The end member is provided with a separable grip member for being gripped when the seal member is removed, which grip member is connected with one end portion of the seal member in a lengthwise direction thereof, and the seal member is passed through a through hole formed in the grip member to be heated and fixed on the grip member. The spike nail thus constructed can be nailed into gypsum board or fiber board walls to facilitate hanging articles. Accordingly, even when the information storage medium is made eccentric or has a manufacturing error, a recording property of the information storage medium is prevented from being degraded due to an influence of an OPC area in an information storage layer upon an OPC area in an adjacent information storage layer. The bonded structure is then cut or ground until a head is formed, having ceramic disposed between each channel. Therefore, when the alignment mark is irradiated with a position correcting electron beam in order to correct a drawing position in the subsequent step of electron beam lithography, electric charges of the electron beam flow into the multilayer film without staying in the alignment mark.