Millions of Dispenses - No Downtime
Pump Provides Precise Dispensing for Glass Slurry Automation Process

When RSM Electron Power Inc., manufacturer of high reliability
hermetic semiconductor and microelectronic components,
decided to automate the slurry dispensing process on their diode
manufacturing line, they chose the QV CeramPump® valveless
piston pump and V-200 Controller from Fluid Metering, Inc.
RSM's line of Sensitron products is designed for use in industries
that require high reliability components. These components are
typically used for aerospace, military, medical, and high
reliability industrial applications. During the diode
manufacturing process, the QV CeramPump® metering pump
dispenses a hermetic coating of 5u glass slurry individually to
each diode as it moves down a conveyor system. The hermetic
design ensures high reliability in applications having temperature
extremes, high altitude, high frequency, and severe
environmental conditions.
Dr. Yunji L. Corcoran, vice president and general manager at
RSM, explains that RSM chose the QV because accuracy and
consistency in the amount of slurry dispensed from diode to
diode is extremely important since many of the operations to
follow will be performed in lots as batch processes. When
processing in lots or batches, correction to compensate for
individual component variation is not possible.

Therefore it is important that processes performed individually
yield components with properties near identical with one another.
Consistency in dispensing can be measured in monitoring both the accuracy and precision of the dispenses.
Accuracy is a comparison of the average value of dispensed amounts to the desired or target value. Precision is
the range or degree of variation from dispense to dispense and will affect component variation. The QV system is
both accurate and precise, capable of providing a 1% dispense accuracy with a 0.5% precision. Along with the V-
200 controller, the system replaced a manual dispensing method and produced cost savings by reducing the
number of components requiring rework due to inconsistent slurry coatings.What makes QV CeramPump® technology so unique is its valveless piston design. One moving part, a special
rotating and reciprocating ceramic piston, accomplishes all fluid control functions of the pump without valves.
The reciprocating action performs the pumping function, while the simultaneous rotation of the piston alternately
aligns a flat on the piston with the inlet and discharge ports of the pump. The flat creates a fluid path between the
ports and the pump chamber, effectively functioning like a valve. At no time during the pumping cycle are the
inlet and discharge ports interconnected, thereby eliminating the need for check valves.
The fluid dispensed during RSM's diode coating process is a proprietary 5u glass slurry. In addition to havingonly one moving part, the CeramPump® has internal components made of sapphire-hard ceramics, providing
excellent wear resistance against the abrasive glass slurry. Tom Merck, facility manager at RSM, estimates that
the QV CeramPump® delivers 200,000 dispenses per week and will operate for about three years or
approximately 32 million dispenses before internal components show enough wear to require replacement.
The QV dispense volume is easily adjusted, without tools, while running or while at rest by using a convenient
flow control knob. A dial indicator gives a direct reading for ultra-fine flow adjustments in dispense volume
settings enabling changing from one dispense volume to another with little or no downtime. Dispense speed is
controlled by the V-200 Stroke Rate Controller, and is adjustable either manually in 0.1% increments or
electronically via a 4-20 mA input common for most process controls. It is useful in controlling production speed,
as well as for fast priming. With virtually only millionths of an inch clearance, the interface between the precision
ceramic piston and mating liner form a fluid seal capable of maintaining pumping pressures up to 100 psig. The
QV pump can also self prime up to 15-ft. vertical lift dry, 30-ft. wet.