Claims
[1] L A gas saver for semiconductor manufacturing, which is connected to a system control unit 24 for controlling a system which is a part of a semiconductor manufacturing apparatus, a user input/output unit 25 for allowing a user to rec- ognizedata input/output and a process condition, a process gas supply apparatus 26 for supplying various gases including nitrogen (N ) gas, which are required for a semiconductor manufacturing process, and a vacuum pump 27, wherein the gas saver comprises: a microprocessor 10 for taking charge of the entire control of system; a user interface 11 for processing data inputted from the user input/output unit 25 and data output from the user input/output unit 25; a system interface 12 for processing data inputted from the system control unit 24 for controlling the system, and outputting the processed data; a timer 13 for extending the supply of nitrogen (N ) gas so that nitrogen (N ) gas is supplied to expel gas impurities existing between the semiconductor manufacturing apparatus and the vacuum pump 27 to the outside, thereby preventing the gas impurities from being discharged without the supply of nitrogen (N ) gas when the supply of (N ) gas is suddenly interrupted; a 1 st valve control unit 14 for controlling a 1 st valve, which is a main valve for supplying nitrogen gas to the vacuum pump; a 2° valve control unit 15 for controlling a 2° valve, which is an auxiliary valve for supplying nitrogen gas to the vacuum pump when the 1 st valve 21 is out of order so that it is not operated; an inverter 16 for transmitting a signal outputted from the 1 st valve control unit 14 to the l'Valve control unit, after inverting the signal; an output signalcomparison unit 17 for comparing whether the 1 st valve 21 is being operated or not with a value sensed by the nitrogen (N ) an input signal comparison unit 18 comparing pressure signals transmitted from a pressure sensing unit 19 as well as voltage signals transmitted from a voltage sensing unit 20 the pressure sensing unit 19 connected to the process gas supply apparatus, the pressure sensing unit 19 receiving and transmitting two pressure signals to the input signal comparison unit 18 the voltage sensing unit 20 connected to the power source of the process gas supply apparatus, the voltage sensing unit 19 receiving and transmitting two voltage signals to the input signal comparison unit 18 the 1 st valve 21 for controlling the supply of nitrogen (N ) gas to the vacuum pump 27, the 1 st valve 21 consisting of an NO (Normal Open) valve the 2° valve for controlling the supply of nitrogen (N ) gas to the vacuum pump
27 when the 1 st valve cannot be operated due to its trouble; and a nitrogen (N ) gas detection sensor 23 for detecting nitrogen gas supplied to the vacuum pump through the 1 st valve 21.
[2] A gas saver as claimed in claim 1, wherein the output signal comparison unit 17 compares whether the 1 st valve 21 is operated or not with the signals sensed by the nitrogen (N ) gas detection sensor so as to determine whether the 2° valve is operated or not.
[3] A gas saver as claimed in claim 1, wherein the pressure sensing unit 19 is comprised of a pressure sensing switch and a pressure sensor, which are provided in an air valve for used in controlling process gasses for semiconductor manufacturing in the process gas supply apparatus, so as to sense the flow of air for controlling the air valve.
[4] A gas saver as claimed in claim 1, wherein the voltage sensing unit is comprised of an SSR (Solid State Relay) which is connected to the power source of the process gas supply apparatus 26 so as to sense two signals at the same part. |
Description
GAS SAVER FOR SEMICONDUCTOR MANUFACTURING
Technical Field
[1] The present invention relates to a gas saver for semiconductor manufacturing,which is employed so as to save process gas in semiconductor manufacturing, wherein the gas saver includes a microprocessor, a user interface, a system interface, a timer, a 1 st valve control unit, a 2° valve control unit, an inverter, an output signal comparison unit, an input signal comparison unit, a pressure sensing unit, a voltage sensing unit, a 1 st valve, a 2° valve, and a nitrogen (N ) gas detection sensor. Background Art
[2] The present invention relates to a gas saver for use in semiconductor manufacturing, and in particular, to a gas saver for saving gas supplied to a semiconductor manufacturing apparatus. Due to semiconductor manufacturing characteristics, a chamber is provided which is required to be maintained in a high vacuum condition, and into which various gases are introduced for a semiconductor manufacturing process to be performed subsequently.
[3] The gases used in the semiconductor manufacturing process as mentioned above are typically controlled separately from the semiconductor manufacturing apparatus because such gases are dangerous due to explosiveness or the like.
[4] As a result, even if the semiconductor manufacturing apparatus is not operated, gases used in a semiconductor manufacturing process are frequently supplied to a process chamber or a discharge apparatus for discharging the gases, which increases the manufacturing costs.
[5] Korean un-examined patent publication No. 10-2004-0075644 (entitled, "Semiconductor Manufacturing Apparatus") discloses a semiconductor manufacturing apparatus including a processor chamber, to which process gases for processing a semiconductor wafer are supplied, a pump for controlling the amount of the process gases within the process chamber so as to control the pressure within the process chamber, and a valve interposed between the process chamber and the pump so as to control the amount of the process gases supplied to the pump from the process chamber, wherein the semiconductor manufacturing apparatus further includes: a pressure sensing unitfor sensing the pressure within the process chamber; an input unit for allowing a user to input one or more parameters for opening the valve; a valve control unitfor controlling the valve in such a manner that theopening/closing of the valve is controlled; and a microcomputer, wherein when the pressure within the process chamber detected through the pressure sensing unit exceeds a predetermined
level, the microcomputer generates an interlock signal for preventing the valve from being opened,even if a valve opening input signal is inputted from the input unit or a valve opening control signal is received from the valve control unit, and when the pressure within the process chamber is below the predetermined level, the microcomputer controls the valve control unit to open the valve.
[6] However, the above-mentioned semiconductor manufacturing apparatus has a disadvantage in that if the pressure within the process chamber is reduced within a predetermined level by controlling the valve depending on the sensed pressure within the process chamber, it is necessary to normally supply a process gas, such as nitrogen (N ) gas, so as to protect a fan of a turbo-pump, thereby greatly increasing the loss of process gas.
[7] In addition, there is a problem in that if the pressure sensing unit for sensing the pressure within the process chamber is out of order and thus the process gas is not smoothly supplied, the corresponding semiconductor manufacturing process is delayed.
Disclosure of Invention Technical Problem
[8] Therefore, the present invention has been made in view of the above-mentioned problems, and the present invention provides a gas saver for semiconductor manufacturing, which is capable of controlling the supply of process gas according to a semiconductor manufacturing process, and the operation of which can be dually controlled through a result of sensing pressure and a result of sensing voltage, whereby the process gas, such as nitrogen (N ) gas, can be saved.
[9] According to another object, the present invention provides a gas saver for semiconductor manufacturing which extends the process gas supply period by a predetermined extent so as to remove gas impurities remaining between a semiconductor manufacturing apparatus and a vacuum pump after interrupting the supply of the process gas, and which also allows the process gas to be supplied in an emergency, e.g., when the gas saver is out of order, so that the semiconductor manufacturing process can smoothly proceed.
[10] In addition, according to another object, the present invention provides a gas saver for semiconductor manufacturing which is operated in cooperation with a process gas supply apparatus so as to minimize any interference with a semiconductor manufacturing apparatus. Technical Solution
[11] In accordance with an aspect of the present invention, there is provided a gas saver for semiconductor manufacturing including: a microprocessor, a user interface, a
system interface, a timer, a 1 st valve control unit, a 2° valve control unit, an inverter, an output signal comparison unit, an input signal comparison unit, a pressure sensing unit, a voltage sensing unit, a 1 st valve, a 2° valve, and a nitrogen (N ) gas detection sensor.
Advantageous Effects
[12] According to the inventive gas saver for semiconductor manufacturing, it is possible to control the supply of process gas according to a semiconductor manufacturing process, and to dually control theoperation of the gas saver through a result of sensing pressure and a result of sensing voltage, whereby the process gas, such as nitrogen (N ) gas, can be saved.
[13] In addition, by extending the process gas supply period by a predetermined extent so as to remove gas impurities remaining between a semiconductormanufacturing apparatus and a vacuum pump after interrupting the supply of the process gas, and allowing the process gas to be supplied in an emergency, e.g., when the gas saver is out of order, the semiconductor manufacturing process can smoothly proceed.
[14] Furthermore, because the inventive gas saver for semiconductor manufacturing is operated in cooperation with a process gas supply apparatus, it is possible for the gas saver to minimize any interference with a semiconductor manufacturing apparatus. Brief Description of the Drawings
[15] The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
[16] FIG. 1 is a schematic view showing a construction of a gas saver for semiconductor manufacturing according to the present invention; and
[17] FIG. 2 is a flowchart for controlling the gas saver according to the present invention.
[18] <Names of Main Parts in the Drawings>
[19] 10: microprocessor
[20] 11 : user interface
[21] 12: system interface
[22] 13: timer
[23] 14: 1 st valve control unit
[24] 15: 2° valve control unit
[25] 16: inverter
[26] 17: output signal comparison unit
[27] 18: input signal comparison unit
[28] 19: pressure sensing unit
[29] 20: voltage sensing unit
[30] 21: 1 st valve
[31] 22: 2 nd valve
[32] 23: nitrogen (N ) sensing unit
Mode for the Invention
[33] Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.
[34] FIG. 1 is a schematic view showing a construction of a gas saver for semiconductor manufacturing according to the present invention.
[35] Referring to FIG. 1, the inventive gas saver for semiconductor manufacturing is connected to a system control unit 24 for controlling a system,which is a part of a semiconductor manufacturing apparatus, a user input/output unit 25 for allowing a user to recognize data input/output and a process condition, a process gas supply apparatus 26 for supplying various gases including nitrogen (N ) gas, which are required for a semiconductor manufacturing process, and a vacuum pump 27.
[36] The inventive gas saver for semiconductor manufacturing includes: a microprocessor 10 for taking charge of theentire control of system; a user interface 11 for processing data inputted from the user input/output unit 25 and data output from the user input/output unit 25; a system interface 12 for processing data inputted from the system control unit 24 for controlling the system, and outputting the processed data; a timer 13 for extending the supply of nitrogen (N ) gas so that nitrogen (N ) gas is supplied to expel gas impurities existing between the semiconductormanufacturing apparatus and the vacuum pump 27 to the outside, thereby preventing the gas impurities from being discharged without the supply of nitrogen (N ) gas when the supply of (N ) gas is suddenly interrupted; a 1 st valve control unit 14 for controlling a 1 st valve, which is a main valve for supplying nitrogen gas to the vacuum pump; a 2° valve control unit 15 for controlling a 2° valve, which is an auxiliary valve for supplying nitrogen gas to the vacuum pump when the 1 st valve 21 is out of order and thus it is not operated; an inverter 16 for inverting a signal outputted from the 1 st valve control unit 14; an output signal comparison unit 17 for comparing whether the 1 st valve 21 is being operated or not with a value sensed by the nitrogen (N ) an input signal comparison unitl8 comparing two pressure signals inputted from a pressure sensing unit 19 as well as two voltage signals inputted from a voltage sensing unit 20, and then comparing a pressure signal comparison value obtained by comparing the two pressure signals and a pressure signal comparison value obtained by comparing the two voltage signals the pressure sensing unitl9 provided in an air valve for controlling the gas supplied to the semiconductormanufacturing apparatus so as to control the
operation of the air valve; the voltage sensing unit 20 provided in the process gas supply apparatus 26 so as to sense the voltage of the process gas supply apparatus 27; the 1 st valve 21 for controlling the supply of nitrogen (N ) gas to the vacuum pump 27; the 2° valve used in an emergency, e.g., when the 1 st valve 21 is out of order and a nitrogen (N ) gas detection sensor23 for detecting nitrogen gas supplied to the vacuum pump through the l st valve 21.
[37] The microprocessor 10 takes charge of general control of the inventive gas saver for semiconductor manufacturing, wherein the microprocessor 10 conducts a command inputted from the system control unit 24, entirely controls the processing of data inputted from the user input/output unit 25 and the transmission of the processed result to the user input/output unit 25, renders the 1 st valve control unit 14 to control the 1 st valve for controlling the supply of nitrogen gas to the vacuum pump 27, and renders the 2° valve control unit 15 to control the 2° valve 22 used in an emergency, such as the trouble of the 1 i st valve 21 or the like.
[38] The comparison values processed by the input signal comparison unit 18, which receives and compares the pressure signal comparison value obtained by comparing the two pressure signals sensed by the pressure sensing unit 19 and the voltage signal comparison value obtained by comparing the two voltage signals sensed by the voltage sensing unit 20, are received and processed by the microprocessor 10, and the signal transmitted to the inverter 16 from the 1 st valve control unit is inverted and transmitted to the 1 st valve 21. With the inverted signal, the l st valve 21 is operated, and nitrogen (N ) gas is supplied to the vacuum pump 27. At this time, the pressure of the flow of the nitrogen (N ) gas is detected by the nitrogen gas detection sensor, and the output signal comparison unit 17 compares whether the 1 st valve is being operated or not with the signal detected by the nitrogen gas detection sensor, so that the 2° valve control unit 15 controls the operation of the 2° valve.
[39] In addition, when the operation of the process gas supply apparatus 26 is stopped and thus the supply of the process gas is stopped, the timer renders nitrogen gas to be additionally supplied overa predetermined length of time, so that the nitrogen gas expels gas impurities or the like existing between the semiconductor manufacturing apparatus and the vacuum pump 27 to the outside, even if the operation of the process gas supply apparatus 26 is stopped. As a result, it is possible to prevent the deposition of gas impurities or the like to the inside of the vacuum pump 27 or to the inner wall of a tubing for carrying waste gas to a waste gas processing apparatus, such as a scrubber, wherein the deposition is caused by discharging the gas impurities existing between the semiconductor manufacturing apparatus and the vacuum pump 27 to the outside without supplying nitrogen gas.
[40] In addition, due to the explosiveness of process gas used in a semiconductor manu-
facturingprocess, an air valve is employed so as to control the process gas, wherein the pressure sensing unit 19 is provided at a side of the air valve and is preferably included of a pressure switch or a pressure sensor so as to sense the pressure of air conveyed or interrupted, thereby controlling the process gas. In order to prevent a malfunction of the pressure sensing unit 19 due to trouble, the pressure sensing unit 19 is included of a pressure switch and a pressure sensor, or included of a pressure switch and a means equivalent to a pressure sensor.According to this measurement, the trouble and/or malfunction of the pressure sensing unit can be confirmed through the comparison of the signals inputted from the two sensing means. Furthermore, when one of the two sensing means gets out of order, the effect onthe semiconductor manufacturing process can be minimized because it is possible to determine whether the operation is being performed normally or not by using the remaining sensing means.
[41] In addition, in order to prevent the malfunction of the inventive gas saver for semi- conductormanufacturing, the operation of the gas saver is controlled through the voltage sensing unit 20 which senses the voltage of the process gas supply apparatus 26, wherein the voltage sensing unit 20 senses and compares two signals at the same part of the power source of the process gas supply apparatus with an SSR (Solid State Relay), thereby preventing the malfunction.
[42] By providing the voltage sensing unit 20 in combination with the above-mentioned pressure sensing unit 19, it is possible to dually prevent the malfunction of the gas saver for semiconductor manufacturing.
[43] In addition, the inverter 16 transmits a signal received from the 1 st valve control unit
14 after inverting the signal. This is because the 1 st valveis an NO (Normal Open) valve, and thus should be operated inversely to the signal generated from the 1 st valve control unit 14. For example, if the l st valve controller 14 commands the l st valve 21 to supply nitrogen gas to the vacuum pump 27, the 1 st valve 21 should be opened so that nitrogen gas can be supplied. Therefore, no voltage is applied to the 1 st valve 21. Consequently, the signal should be inverted through the inverter 16.
[44] The reason why inverting the signal through the inverter as mentioned above is to supply nitrogen gas to the vacuum pump 27 regardless of the operation of the inventive process gas saver for semiconductor manufacturing, so that the semiconductormanu- facturing process is not affected in an emergency, e.g., when the process gas saver is out of order.
[45] In addition, in an emergency, e.g., when the 1 st valve 21 for supplying nitrogen gas to the vacuum pump 27 is out of order, the 2° valve 22 is separately operated so that nitrogen gas is supplied to the vacuum pump 27. Because the 2° valve 22 is controlled by the 2° valve control unit 15, and is used in an emergency, it is sufficient for the 2° valve 22 to supply process gas to the vacuum pump 27 according to the operation of
the process gas supply apparatus. As a result, the 2° valve 15 is controlled by the 2° valve control unit 15 without the inverter 16.
[46] The nitrogen gas detection sensor 23 senses whether the 2° valve 22 is operated or not, and the nitrogen delivered to the vacuum pump 27 from the 1 st valve 21, and transmitstwo sensed signals to the output signal comparisonunit 17, so that the two sensed signals are compared with each other by the output signal comparison unit 17. If the two signals do not correspond to each other, the trouble and malfunction of the 1 st valve 21 are estimated so as to determine whether to operate the 2° valve 22 or not.
[47] By repeating a series of operations as mentioned above, the inventive process gas saver for semiconductor manufacturing is completed.
Next Patent: MODULAR STEEL BRIDGE