Hafnium oxide production via laser ablation plasma deposition

Summary form only given. This research investigates the feasibility of synthesizing thin films of hafnium oxide via ablation plasma ion implantation (APII). HfO₂ is of great interest as a high-dielectric-constant material in the semiconductor fabrication industry and may also have applications to high power microwave windows or cathodes. Experiments are underway at UM to deposit and implant films of hafnium and hafnium-oxide on silicon substrates. A KrF laser (400 mJ @ 248 nm) ablates solid Hf foils or sintered pellets of hafnium-oxide. Silicon substrates can be biased (- or + , either pulsed or DC) by voltages up to 10 kV for ion implantation and deposition. The experiments will study correlations among parameters such as laser energy, film thickness, background gas pressure, film composition, and ion energy. Ablation plasma plumes are characterized by optical emission spectroscopy. Composition and morphology of deposited films are analyzed by scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy. Thin film adhesion is also being tested. X-ray diffraction is being used to determine if the Hf films are amorphous or crystalline. Deposition rates are estimated to be on the order of 0.055 nm/pulse at a laser repetition rate of 20 pulses