A new superhard and conductive (Al, Mg)-doped boron thin film with AlMgB@sub 14@ stoichiometry has been developed in this work for potential application as a hard coating on MEMS components and conductive atomic force microscope cantilevers. AlMgB@sub 14@ films were prepared on Si (100) using pulsed laser deposition at room temperature and 573 K. Transmission electron microscopy analysis reveals that the film structures are amorphous irrespective of substrate temperature during deposition. Nanoindentation tests show that hardnesses of 45 GPa and 51 GPa have been achieved in AlMgB@sub 14@ films deposited at room temperature and 573 K respectively. Except for their superhardness, AlMgB@sub 14@ films also display very low electrical resistivity and high optical absorption in a broad spectrum range, all these phenomena can be accounted for based on an electron transfer mechanism enhanced in amorphous structures.