A memory cell array having a plurality of memory cells is disclosed. In the presence of a predetermined solvent, a \u03b2-amino-\u03b1-hydroxycarboxylic acid is reacted with an amine to conversion to a \u03b2-amino-\u03b1-hydroxy carboxamide derivative; then the derivative is deprotected for conversion to a \u03b2-amino-\u03b1-hydroxy carboxamide derivative; and the derivative is crystallized using a protic solvent to obtain a crystal. After assembly, each reference surface is located inside a notch defined in the edge surface. The exposed top end of the alignment pin is configured to mate with the insertion end of a blade pin.