Characterizations of Hf_xMo_yN_z Alloys as Gate Electrodes for n- and p-Channel Metal Oxide Semiconductor Field Effect Transistors

In this article, the work functions (phi(m)) of hafnium-molybdenum (HfxMoy) alloys were modified using nitrogen in de reactive cosputtering for the first time. The HfxMoyNz alloys show low resistivity and excellent thermal stability up to 900 degrees C. In addition, the work functions (Phi(m)) of the HfxMoyNz alloys were tuned from the conduction band (4.17 eV) to the valence band (5.16eV) by increasing the nitrogen flow ratio. From the X-ray diffraction (XRD) data, the MoN(200) peak can be observed for samples with a nitrogen ratio higher than 6%, which was responsible for the work function (Phi(m)) increase in the HfxMoyNz alloys.