Fabrication and Property Evaluation of Mo Compacts for Sputtering Target Application by Spark Plasma Sintering Process

Abstract

Pure molybdenum compacts having a high density, purity and a fine-grained microstructure were fabricated by a spark plasma sintering process. Also, an optimized sintering condition was obtained by controlling process parameters such as temperature, pressure, and heating rate. Molybdenum compacts were prepared with diameters of Φ150 × 6.35 mm, and the characteristics of the compacts were analyzed by induction couple plasma (ICP), X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). In addition, molybdenum thin films that were fabricated on a glass substrate by using sputtering equipment were analyzed by XRD, transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS). A relative density of up to 99% and the grain size of below 8 µm were reached at the sintering temperature of 1473.15 K and the uniaxial pressure of 60 MPa. Also, molybdenum compacts having a uniform relative density and grain size were fabricated through an optimully redesigned mold and process control method. The resistivity (~0.15 μΩm) of the optimized spark plasma sintering (SPS) molybdenum thin film showed properties that are similar to those of the film prepared with conventional sintering.