Yoji Kawasaki’s research while affiliated with Sumitomo Heavy Industries, Ltd and other places

Ga has been studied as an alternative p-type dopant to boron due to its higher solid solubility in germanium and silicon germanium. A key challenge in the ion implantation of Ga is the introduction of Ga atoms into the plasma chamber of an ion source. This study presents a novel vaporization method for Ga ion production using a high-temperature vaporizer and a tablet technique for Ga compounds. This method enables the production of a high beam current of Ga ions with a long lifetime. In the initial phase of improvement, a Ga ion beam current of 10.4 mA was observed with a 40 kV extraction voltage. A stable Ga ion beam current of 7 mA was achieved with a 30 kV extraction voltage over 850 min. The results in this study demonstrate the potential advantages of using a high-temperature vaporizer and tablet technique for Ga compounds.