초록 ▼

A vacuum control system using a vacuum pump to control a vacuum pressure and a flow of a processing gas in a vacuum chamber. The vacuum control system includes: a plurality of vacuum control valves, each of the valves being connected between each of a plurality of gas discharge ports and the vacuum

A vacuum control system using a vacuum pump to control a vacuum pressure and a flow of a processing gas in a vacuum chamber. The vacuum control system includes: a plurality of vacuum control valves, each of the valves being connected between each of a plurality of gas discharge ports and the vacuum pump; a pressure measurement unit configured to measure the vacuum pressure of the processing gas supplied to the object; and a controller configured to manipulate respective openings of the valves in accordance with the measured vacuum pressure.

대표청구항 ▼

1. A vacuum control system using a vacuum pump to control a vacuum pressure and a flow of a processing gas in a vacuum chamber, the vacuum chamber being for processing on an object with the processing gas provided from a gas supply unit, the vacuum control system comprising: a plurality of vacuum co

1. A vacuum control system using a vacuum pump to control a vacuum pressure and a flow of a processing gas in a vacuum chamber, the vacuum chamber being for processing on an object with the processing gas provided from a gas supply unit, the vacuum control system comprising: a plurality of vacuum control valves, each of the valves being connected between each of a plurality of gas discharge ports and the vacuum pump, the plurality of gas discharge ports being disposed in different positions of the vacuum chamber; a pressure measurement unit configured to measure the vacuum pressure of the processing gas supplied to the object; and a controller configured to manipulate respective openings of the valves in accordance with the measured vacuum pressure: wherein the plurality of gas discharge ports are disposed in positions sandwiching a process reaction region inside of the vacuum chamber, the process reaction region being a space where the processing is performed, and the pressure measurement unit measures a vacuum pressure of the processing reaction region, wherein the controller compensates for at least one of conductance differences and individual differences, the conductance differences being conductance differences from the processing reaction region to the respective gas discharge ports, the individual differences being individual differences among respective exhaust systems including the vacuum pump and the vacuum control valves, whereby exhaust flow rates of the plurality of vacuum control valves approach each other, wherein the controller includes: an offset value storage unit configured to store an offset value used to compensate for at least one of the conductance differences and the individual differences, wherein the offset value is related to units of length; and a target value setting unit configured to set a target value for controlling the openings of the plurality of vacuum control valves, using the offset value read from the offset value storage unit, and wherein the plurality of vacuum control valves have a shutoff function for blocking the gas flow; the controller is configured to generate the offset value on the basis of characteristic data relating to each of the plurality of vacuum control valves and to store the generated offset value in the offset value storage unit; and the characteristic data are data for setting the target value obtained in a state where one of the plurality of vacuum control valves is operative and the other vacuum control valve is closed. 2. The vacuum control system according to claim 1, wherein the controller includes: a main control unit configured to output a common opening command value that is a common command value for manipulating the respective openings of the plurality of vacuum control valves according to the measured vacuum pressure; and a plurality of dependent control units configured to control the respective openings of the plurality of vacuum control valves according to the common opening command value, each of the plurality of dependent control units being provided for each of the vacuum control valves, wherein the respective dependent control units obtain actually measured values of the openings of the respective vacuum control valves and control the openings of the respective vacuum control valves based on the actually measured values, the common opening command value, and the offset value. 3. The vacuum control system according to claim 1, wherein the plurality of vacuum control valves are vacuum control valves for controlling the vacuum pressure in the vacuum chamber by manipulating valve opening using working fluid, whereinthe vacuum control valve includes: a control valve main body having a flow passage and a valve seat formed in the flow passage, the flow passage connecting the vacuum chamber and the vacuum pump;an operation unit having a valve body, a piston, and a rod that joins the valve body and the piston, the valve body manipulating the valve opening by adjusting a lift and blocking the flow passage by contacting the valve seat, the lift being a distance between the valve body and the valve seat;a cylinder connected to the control valve main body and housing the piston;a biasing unit configured to press the operation unit in a direction for reducing the lift; anda bellofram configured to seal a gap between an outer peripheral surface of the piston and an inner peripheral surface of the cylinder following a movement of the piston, whereinthe operation unit and the cylinder include: a valve opening manipulation chamber sealed by the bellofram, the valve opening manipulation chamber having a tubular shape surrounding the rod, wherein valve opening manipulation chamber generates a load applied to the piston in a direction for increasing the lift in accordance with a pressure exerted by the working fluid; anda shutoff load generation chamber configured to have a common axial center line with the valve opening manipulation chamber and to generate a load applied to the operation unit in a direction for reducing the lift in accordance with a supply of the working fluid. 4. The vacuum control system according to claim 3, wherein the cylinder includes a head cover having a sliding convex portion accommodated in the shutoff load generation chamber, whereinthe vacuum control valve includes: a sealing unit having a sealing surface sealing between the shutoff load generation chamber and the sliding convex portion, whereina surface pressure of the sealing surface increases according to the supply of the working fluid to the shutoff load generation chamber. 5. The vacuum control system according to claim 4, wherein the sliding convex portion has a cylindrical shape with a common central axis line with the valve opening manipulation chamber,an outer diameter of the sliding convex portion is smaller than an inner diameter of the valve opening manipulation chamber,the operation unit includes a guide portion extending in an operation direction within a space surrounded by an inner peripheral surface of the sliding convex portion, andthe vacuum control valve is disposed between the guide portion and the sliding convex portion, for enabling the slide in the operation direction, whereinthe vacuum control valve has a bearing for restraining a positional relationship between the guide portion and the sliding convex portion in a perpendicular direction to the operation direction. 6. The vacuum control system according to claim 3, wherein the shutoff load generation chamber is formed inside of the rod. 7. The vacuum control system according to claim 3, wherein the controller includes: a pressure sensor configured to measure the vacuum pressure in the vacuum chamber;a pneumatic circuit configured to supply the working fluid to the vacuum control valve, the pneumatic circuit being connected to a working fluid supply unit and a working fluid discharge unit, the working fluid supply unit supplying the working fluid, the working fluid discharge unit discharging the working fluid; anda control unit configured to control the vacuum pressure in the vacuum chamber by manipulating the working fluid supplied to the vacuum control valve from the pneumatic circuit. 8. The vacuum control system according to claim 7, wherein the controller is configured to connect a flow passage between the valve opening manipulation chamber and the working fluid discharge unit and a flow passage between the shutoff load generation chamber and the working fluid supply unit, in response to a reception of a vacuum pump stop signal including information indicative of stoppage of the vacuum pump. 9. The vacuum control system according to claim 7, wherein the pneumatic circuit includes: a first solenoid valve configured to connect the flow passage between the valve opening manipulation chamber and the working fluid discharge unit in a non-energized state; anda second solenoid valve configured to connect the flow passage between the shutoff load generation chamber and the working fluid supply unit in the non-energized state. 10. A vacuum control method using a vacuum pump to control a vacuum pressure and a flow of a processing gas in a vacuum chamber, the vacuum chamber being for processing on an object with the processing gas provided from a gas supply unit, the vacuum control method comprising the steps of: a providing step of providing respective vacuum control valves connected between a plurality of gas discharge ports disposed in different positions within the vacuum chamber and the vacuum pump; a measuring step of measuring the vacuum pressure of the processing gas supplied to the processing object; and a controlling step of manipulating respective openings of the plurality of vacuum control valves in accordance with the measured vacuum pressure: wherein the plurality of gas discharge ports are disposed in positions sandwiching a process reaction region inside of the vacuum chamber, the process reaction region being a space where the processing is performed, and the measuring step includes a step of measuring a vacuum pressure of the processing reaction region, wherein the controlling step includes: compensating for at least one of conductance differences and individual differences, the conductance differences being conductance differences from the processing reaction region to the respective gas discharge ports, the individual differences being individual differences among respective exhaust systems including the vacuum pump and the vacuum control valves, whereby exhaust flow rates of the plurality of vacuum control valves approach each other; storing an offset value used to compensate for at least one of the conductance differences and the individual differences; setting a target value for controlling the openings of the plurality of vacuum control valves, using the offset value read from an offset value storage unit; and generating the offset value on the basis of characteristic data relating to each of the plurality of vacuum control valves and storing the generated offset value in the offset value storage unit, wherein the offset value is related to units of length, and wherein the plurality of vacuum control valves have a shutoff function for blocking the gas flow, and the characteristic data are data for setting the target value obtained in a state where one of the plurality of vacuum control valves is operative and the other vacuum control valve is closed.