PRE-HEATING DILUTION GAS BEFORE MIXING WITH STEAM IN DIFFUSION FURNACE

摘要

Embodiments of the present invention are directed to apparatus and methods of supplying a diluted process gas into a diffusion furnace for forming an oxide layer on a substrate in the diffusion furnace. One or more inlet gases are supplied into a chamber, and are heated in the chamber to generate an oxidizing gas such as steam. A dilution gas is flowed through a dilution gas line which extends through the chamber to permit heating of the dilution gas by the heat in the chamber without mixing the dilution gas and the oxidizing gas in the chamber. The oxidizing gas and the heated dilution gas are mixed downstream of the chamber prior to entry into the diffusion furnace.