Online information source for semiconductor professionals

Product Briefing Outline: Levitronix has introduced the new ‘BPS 600’ magnetically levitated pump technology, designed for demanding applications in the semiconductor industry such as CMP slurry delivery, copper electroplating and wafer cleaning at leading-edge process nodes. The patented impeller floats in a magnetic field only touching the fluid it is pumping, and can be fully integrated into a fully-closed loop electronic control system without the need of additional controller hardware. 

Problem: Magnetic bearings are ideally suited for cleanroom applications because they do not require lubrication and are capable of operating without generating particles. Extensive slurry recirculation or improper distribution hardware may lead to slurry agglomeration or large particle formation that may result in increased levels of micro-scratches and other defects on polished wafer surfaces.

Solution: The BPS 600 is ideal for CMP slurry delivery because it eliminates shear stress and mechanical contact which cause particle agglomeration. The moderate shear level to which the slurry is exposed in maglev pumps seems to have a beneficial effect on the slurry by breaking apart loose agglomerates. In copper electroplating applications, the solution cannot plate out and clog the pump. The closed loop electronic control makes the BPS 600 ideal for wafer cleaning. The pump can sense pressure and flow at the tool and adjust itself automatically. Continuous flow with no pulsation generates repeatable cleaning conditions.

Applications: The BPS 600 can be used for CMP slurry delivery, copper electroplating and wafer cleaning applications.

Platform: The centrifugal pump design that has no bearings to wear out or seals to break down and fail. Based on the principles of magnetic levitation, the pump’s impeller is suspended, contact-free, inside a sealed casing and is driven by the magnetic field of the motor. The impeller and casing are both fabricated from chemical-resistant high purity fluorocarbon resins. Fluid flow rate and pressure are precisely controlled by electronically regulating the impeller speed. Two basic system configurations are available: a ‘stand-alone’ configuration consists of a controller with an integrated user panel to set the speed manually, while the ‘extended’ version consists of a controller with integrated PLC interface. This allows setting the speed by an external signal and enables precise flow or pressure control in connection with either a flow or a pressure sensor.

Availability: May 2008 onwards.