Patent ID: 7410668

Claim:
A method comprising: introducing gas into a closed inner chamber within an outer chamber through a gas-distribution fixture in a chemical-vapor-deposition system, with the fixture for distributing gas over a substrate; operating a pump to evacuate gas from the outer chamber through the gas-distribution fixture, wherein evacuating gas occurs after introducing gas; and changing relative position of the gas-distribution fixture and a substrate to form the closed inner chamber from the gas distribution fixture and a substrate holder before introducing gas, wherein the gas-distribution fixture includes a gas-distribution surface having a plurality of holes and a gas-confinement member extending from the gas-distribution surface around the plurality of holes; and wherein changing relative position of the fixture and the substrate includes moving the fixture from at least a first operating position where the gas-confinement member is physically apart from the substrate holder to a second operating position where the gas-confinement member is in physical contact with the substrate holder.