| 摘要 |
PURPOSE:To improve uniformity of etched quantity within a batch by a method wherein the flow rate of carrier gas is set at a lower value than that of vapor phase deposition when vapor phase etching is performed. CONSTITUTION:The flow rate of carrier gas is depressed to a lower value than that of vapor phase deposition process, and vapor phase etching is performed. For example when epitaxial growth is performed utilizing SiH4 as a silicon source, the flow rate of a carrier gas (H2) during vapor phase deposition is increased to supress ununiformity of epitaxial film thickness due to lower temperature for thermal decomposition of SiH4 than that for vapor phase deposition. And when vapor phase etching utilizing HCl is performed to clean the substrate before vapor phase deposition process, flowing of raw HCl gas along the gas flow direction to a outlet side is hindered by depressing carrier gas flow rate to a lower value than that of vapor phase deposition. By that method uniformity of the etched quantity within a batch is improved without too much etched quantity at the outlet side. |
