CMP Point of Use Chemical Dilution

Semiconductor manufacturing customers are seeking ways to reduce process costs without impacting the process itself. Semiconductor production facilities have numerous Chemical Mechanical Planarization (CMP) tools that use an abrasive process for polishing the surface of the wafer flat. Planarization areas are opportunities to pursue such improvements.
At various times during the CMP process, fluids are delivered to the wafer for polishing or rinsing using a pressurized chemical system. During the rinse phase a chemical, usually acid or ammonia, is diluted 40:1 with de-ionized (DI) water. McMillan Liquid Flo-Controllers combine smart electronics with a precision control valve and flow sensor. The output from the flow sensor is analyzed and compared to the flow rate set point. The control valve is then automatically adjusted to achieve the required flow.
The DI water and the chemical are mixed downstream of the Model U801 Flo-Controllers and delivered to the wafer. The controller uses an external set-point, output signal and standby mode for process control and monitoring. Standby mode overrides control functions and freezes valve position, while still providing flow output signals for monitoring purposes. Normal operation resumes when standby is disengaged.
The Liquid Flo-Controllers provide consistent flow regardless of small pressure changes and can be configured for available system pressure. The control module has an LCD display, status and standby LED indicators for visual reference. DIP switches on the control module allow the user to view flow, choose internal or external set-point and manually activate standby mode. Benefits to our customers include a reduction in process cost, reduced maintenance and improved consistency.

Call 1.925.443-9800 for more information or to schedule a visit with a Microelectronics sales representative.