Method and apparatus for processing semiconductor substrates

A process for treating semiconductor substrates, in which at least one process gas for the treatment of the substrates is generated in a first chamber and the process gas is subsequently passed into a process chamber, characterized in that the first chamber is a combustion chamber and to form the process gas of water vapor and hydrogen oxygen is burned in a hydrogen-rich environment in the combustion chamber, more hydrogen is present as for the combustion of oxygen is required.