Patent ID: 7731162

Claim:
A liquid substance supply device that supplies a liquid substance, which comprises a liquid organometal or an organometal solution and is stored in a substance container, via a liquid substance transfer line to a vaporizer, the liquid supply device comprising: a three port two valve directional control valve that is of unitary structure and includes: a first valve body which is provided between a first conduit and a second conduit and performs an ON-OFF control of transfer of fluid between said first conduit and said second conduit, and a second valve body which is provided between said second conduit and a third conduit and performs an ON-OFF control of transfer of fluid between said second conduit and said third conduit, said second conduit being provided between said first valve body and said second valve body, and a detection device that is provided at said liquid substance transfer line, and detects a presence or absence of the liquid substance in said liquid substance transfer line, or a presence or absence of bubbles generated from the liquid substance by using a photoelectric sensor, wherein said three port two valve directional control valve is disposed at a branch point where said liquid substance transfer line branches into three directions.