| 摘要 |
<p>An atmospheric pressure wafer processing system (100) for delivering at least one gas, having an exhaust control feedback system that utilizes sensors (116, 142, 162, 182, 192) to measure the pressure within the system and adjusts control units (112, 132, 152, 180, 196) to maintain the desired set pressures within the system. The sensors measure the small differential pressures inside a muffle (140), and specifically the load (136), bypass center, and unload (156) sections of the muffle, relative to the chase ambient pressure. Controlling the muffle pressures directly within the atmospheric system yields a more stable pressure balance less subject to changes in the external environment and allows for compensation of varying input gas flows as occurs when the supply pressure to the system may vary. This system and method of pressure control is particularly advantageous for chemical vapor deposition application yielding improved process repeatability over an extended period of runtime.</p> |
