- > designed to measure and control the
mass flow rate of doping materials by
- varying the flow of carrier gas through a
bubbler containing the source material.
Features
True vapor
mass flow in bubbler systems.
Defeats influence of liquid level, temperature and pressure.
Liquid
level
surveillance possible.
Mounting position insensitive.
Good surface finish for ultra clean operation.
Various gas fitting configurations.
Heating temperature of bubbler much lower compared with direct
vaporization.
Thermal control valve design gives:
- >
reliability,
- >
no hysteresis,
- >
smooth, fine control,
- >
a normally open flow path for gas line purging when power is off