The manufacturing technology of grade 6 N high-purity indium metal for compound semiconductor

This study prepared high-purity indium metal using raw materials recovered from process chips (Cu-Chip) in the electronics industry, and designed and modified a pilot device based on the Czochralski (CZ) method. The crystallinity of indium metal, which is crystallized at the reaction temperature of 180-230 degrees C, was lowered since its rotation speed and pulling speed were faster than the crystal growth rate. Next, surface oxidation and corrosion during the CZ process were solved in a relatively simple manner. Only C, Al, and In were detected from the crystallized indium metal surface, while no O was detected. The study showed that the impurity content before and after the CZ process decreased and detected very small amounts of Sn, Fe, Si, Pb, etc. in several ppb with the purity of grade 6N (99.99996%). (C) 2020 Elsevier Ltd. All rights reserved.