Liquid material vaporization and supply device, and control program

Patent metadata

Field	Value
Publication number	US-11066746-B1
Application number	US-201816491466-A
Country	US
Kind code	B1
Filing date	Apr 13, 2018
Priority date	May 11, 2017
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A liquid material vaporization and supply device is provided in which it is possible to accurately control a flow rate even in the case where calibration data is not available for a material gas. A first tank in which a liquid material is vaporized to produce material gas; a second tank in which the material gas is contained at a predetermined pressure; a pressure sensor that senses the pressure inside the second tank; a lead-out path for leading the material gas out of the second tank; a fluid control valve that is provided to open/close the lead-out path; and a flow rate control part that, when the material gas is led out through the lead-out path, on the basis of a reduction in the pressure sensed by the pressure sensor, controls the opening level of the valve to control the flow rate of the material gas are included.

First claim

The invention claimed is:

1. A liquid material vaporization and supply device comprising:
a first tank in which a liquid material is vaporized to produce material gas;
a second tank that is connected to the first tank and in which the material gas produced in the first tank is contained at a predetermined pressure;
a pressure sensor that senses pressure inside the second tank;
a lead-out path for leading the material gas out of the second tank;
a fluid control valve that is provided in the lead-out path to open/close the lead-out path; and
a flow rate control part that, when the material gas contained in the second tank at the predetermined pressure is led out through the lead-out path, on a basis of a reduction in the sensed pressure sensed by the pressure sensor, controls an opening level of the fluid control valve to control a flow rate of the material gas led out through the lead-out path.

2. The liquid material vaporization and supply device according to claim 1 , wherein
the flow rate control part comprises:
a flow rate calculation part that, on a basis of a reduction amount of the sensed pressure sensed by the pressure sensor per unit time, calculates a flow rate of the material gas led out of the second tank within the unit time; and
a valve control part that, on a basis of a deviation between the calculated flow rate calculated in the flow rate calculation part and a preset set flow rate, controls the opening level of the fluid control valve.

3. The liquid material vaporization and supply device according to claim 2 , wherein
the flow rate control part further comprises a unit time changing part that, on a basis of the set flow rate, changes the unit time, and changes the unit time to be longer as the set flow rate is made smaller.

4. The liquid material vaporization and supply device according to claim 2 , wherein
multiple second tanks are connected to the first tank,
the liquid material vaporization and supply device further comprising
an introduction tank number adjustment part that, on a basis of the set flow rate, adjusts the number of the second tanks to which the material gas is to be introduced.

5. The liquid material vaporization and supply device according to claim 1 , further comprising
a flow rate sensor that senses the flow rate of the material gas led out through the lead-out path, wherein
the flow rate control part comprises:
a valve control part that, on a basis of a deviation between the sensed flow rate sensed by the flow rate sensor and a preset set flow rate, controls the opening level of the fluid control valve;
a flow rate calculation part that, on a basis of a reduction amount of the sensed pressure sensed by the pressure sensor per unit time, calculates a flow rate of the material gas led out of the second tank within the unit time; and
a set flow rate correction part that, on a basis of a deviation between the calculated flow rate calculated in the flow rate calculation part and the set flow rate, corrects the set flow rate.

6. The liquid material vaporization and supply device according to claim 1 , wherein
the flow rate control part comprises:
a flow rate calculation part that, on a basis of a reduction amount between sensed pressure sensed by the pressure sensor at a predetermined timing and sensed pressure sensed after a predetermined time has elapsed since the predetermined timing, calculates a flow rate of the material gas led out of the second tank within the predetermined time;
an assumed flow rate calculation part that assumes a case where the material gas is led out of the second tank in accordance with a preset set flow rate, and under this assumption, calculates a flow rate of the material gas led out within the predetermined time; and
a valve control part that, on a basis of a deviation between the calculated flow rate calculated in the flow rate calculation part and an assumed flow rate calculated in the assumed flow rate calculation part, controls the opening level of the fluid control valve.

7. The liquid material vaporization and supply device according to claim 6 , wherein
on a basis of a reduction amount of sensed pressure sensed per unit time by the pressure sensor every unit time since the predetermined timing, the flow rate calculation part calculates a flow rate of the material gas led out of the second tank within each unit time, and on the basis of each resulting calculated flow rate, calculates the flow rate of the material gas led out of the second tank within the predetermined time.

8. The liquid material vaporization and supply device according to claim 1 , wherein
the flow rate control part comprises:
an assumed pressure calculation part that assumes a case where the material gas is led out of the second tank in accordance with a preset set flow rate, and under this assumption, calculates assumed pressure inside the second tank after a predetermined time has elapsed since the material gas started to be led out; and
a valve control part that, on a basis of a deviation between sensed pressure sensed by the pressure sensor after the predetermined time has elapsed since the material gas started to be led out of the second tank and the assumed pressure calculated in the assumed pressure calculation part, controls the opening level of the fluid control valve.

9. The liquid material vaporization and supply device according to claim 1 , further comprising
a temperature sensor that senses temperature inside the second tank, wherein
the flow rate control part further comprises
a sensed pressure correction part that, on a basis of the sensed temperature sensed by the temperature sensor, corrects the sensed pressure sensed by the pressure sensor.

10. The liquid material vaporization and supply device according to claim 1 , further comprising
a pressure control mechanism that controls the material gas introduced from the first tank to the second tank to a predetermined pressure.

11. The liquid material vaporization and supply device according to claim 10 , wherein
the pressure control mechanism comprises:
an on-off valve that adjusts a flow rate of the material gas introduced from the first tank to the second tank; and
a pressure control part that opens/closes the on-off valve, and on a basis of a differential pressure between the first tank and the second tank, controls pressure of the material gas introduced to the second tank.

12. The liquid material vaporization and supply device according to claim 11 , wherein
the pressure control part adjusts temperature of a heater for heating the first tank, and controls the differential pressure between the first tank and the second tank.

13. The liquid material vaporization and supply device according to claim 11 , wherein
the pressure control part stops introducing the material gas to the second tank when the sensed pressure sensed by the pressure sensor reaches a predetermined pressure.

14. The liquid material vaporization and supply device according to claim 10 , wherein
the pressure control mechanism comprises:
a pump that forcibly introduces the material gas from the first tank to the second tank; and
a pressure control part that stops driving of the pump, and controls pressure of the material gas introduced to the second tank.

15. A computer-readable storage medium configured to store a control program for a liquid material vaporization and supply device comprising: a pressure sensor that senses pressure inside a second tank in which material gas is contained at a predetermined pressure from a first tank in which a liquid material is vaporized to produce the m

Assignees

• Horiba Stec Co Ltd

Inventors

• Miyamoto Hideaki

Classifications

• B01F23/19

  Mixing systems, i.e. flow charts or diagrams; Arrangements, e.g. comprising controlling means · CPC title

• Y02E60/50

  Fuel cells · CPC title

• B01J4/008

  Feed or outlet control devices · CPC title

• G05D7/0635 Primary

  by action on throttling means (G05D7/0688, G05D7/0694 take precedence) · CPC title

• C23C16/448 Primary

  characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials · CPC title