A memory comprising substrates is provided. Each substrate comprises a through-hole area at center; a first contact area at a side of the through-hole area; and a second contact area at another side of the through-hole area. The substrate uses its first or second contact area to mutually electrically connects to the first or second contact area of the another substrate through the through-hole area. After the pins of the memory having at least PAR pin included are electrically connects to the first and second contact areas of the substrate, all the substrates obtain mutual connections across layers through signal lines with the guidance of the through-hole areas. Thus, on fabricating the memory, reference layer is effectively prevented from breaks with good power distribution and sufficient wiring space achieved while good signal integrity is further maintained.