Patent ID: 6857543

Claim:
A low volume-dispense unit for dispensing a chemical solution in the small-scale manufacture of semiconductors, comprising: a stand connectable to a semiconductor coat/develop track machine; a pressurized reservoir for a chemical solution; a pneumatic two-stage diaphragm valve assembly, said pneumatic two-stage diaphragm valve assembly including a stop portion in fluid communication with said pressurized reservoir and a suck-back portion; a dispensing nozzle in fluid communication with said suck-back portion, said dispensing nozzle being extendable into said semiconductor coat/develop track machine, said stand supporting said reservoir, said pneumatic valve assembly, and said dispensing nozzle; and a flow path being defined by said pressurized reservoir, said pneumatic two-stage diaphragm valve assembly, and said dispensing nozzle, said flow path having a low hold-up volume and having materials sufficient to withstand said chemical solution, said stop portion being movable from a closed position sealing said flow path to an open position unsealing said flow path by a pneumatic pressure, and being returned to said closed position upon removal of said pneumatic pressure, said chemical solution being dispensable into said semiconductor coat/develop track machine at said dispensing nozzle from said pressurized reservoir in said open position, and said suck-back portion being movable from a first position when said stop portion is in said closed position to a second position when said stop portion is in said open position by said pneumatic pressure, and being returned to said first position upon removal of said pneumatic pressure to suck-back said chemical solution in said flow path at said nozzle.