Moisture-Induced Side Reactions in Metal Powder Synthesis through Chemical Vapor Process

The chemical vapor synthesis process is a widely used method for producing the powder for the electrode layer in electronic components such as multilayer ceramic capacitors. This process utilizes solid metal chloride as a precursor. The metal chloride is vaporized and then reduced with a reducing gas, such as hydrogen, to form metal powder. A common issue in this process is the unintentional introduction of moisture into the reactor along with the metal chloride powder precursors. This moisture can lead to unintended side reactions. To address this issue, our study conducted a thermodynamic analysis of the side reactions caused by moisture in the reactor. We experimented by injecting HCl gas, a by-product of these reactions, and observed the impact at different partial pressure ratios. This research aids in comprehending and potentially preventing the detrimental effects of moisture in chemical vapor synthesis.