JP4251429B2 - Liquid material vaporizer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid material vaporizer that vaporizes a liquid material used, for example, in semiconductor manufacturing.
[0002]
[Prior art]
An example of a conventional liquid material vaporizer is shown in FIG. That is, FIG. 4 shows a main part of a conventional liquid material vaporizer. In this figure, reference numeral 41 denotes a rectangular parallelepiped main body block in which three flow paths 42, 43, 44 are formed. A gas-liquid mixing chamber 45 is formed on the upper surface thereof.
[0003]
The flow path 42 introduces a liquid material LM (not shown) into the gas-liquid mixing chamber 45. The liquid material introduction path 42 is provided in a direction perpendicular to the paper surface, and one end of the liquid material introduction path 42 is a main body. The block 41 has an inverted L shape so that it opens to the front side and the other end opens to the upper surface of the main body block 41. The flow path 43 introduces the carrier gas CG into the gas-liquid mixing chamber 45. One end of the carrier gas introduction path 43 opens on the left side of the main body block 41 and the other end of the main body block 41. An L-shape is formed so as to open in the recess 41a on the upper surface of the. The flow path 44 functions as a gas lead-out path. One end of the flow path 44 is opened on the right side surface of the main body block 41, and the other end is formed substantially in a straight line up to an appropriate position of the main body block 41. It continues to the gas-liquid mixing part 45 through the nozzle part 46.
[0004]
The gas-liquid mixing chamber 45 is formed so that a recess 41a formed on the upper surface of the main body block 41 is covered with a diaphragm 47 as a valve member. The diaphragm 47 is accommodated in a valve block 48 provided on the upper surface of the main body block 41, and is pressed downward by a piezo actuator 49 provided upright on the valve block 48. Reference numeral 50 denotes a spring that constantly biases the diaphragm 47 upward. Reference numeral 51 denotes a heater for heating the main body block 41.
[0005]
The nozzle portion 46 is a small one having a diameter and a length of, for example, 1.0 mm or less, and is provided in the most upstream portion of the gas outlet passage 44 on the downstream side in the vicinity of the gas-liquid mixing chamber 45. The gas-liquid mixture generated in the gas-liquid mixing chamber 45 is discharged to the gas outlet path 44 by passing through the nozzle portion 46, whereby the liquid material contained in the gas-liquid mixture is vaporized by decompression. This gas is mixed with the carrier gas CG to become a mixed gas KG and flows downstream through the gas outlet path 44.
[0006]
In the liquid material vaporizer configured as described above, the liquid material LM and the carrier gas CG are mixed while controlling the flow rate of the liquid material LM in the gas-liquid mixing chamber 45 provided in the main body block 41 heated to an appropriate temperature. Then, the gas-liquid mixture is passed through the nozzle portion 46 formed in the main body block 41 in the vicinity of the gas-liquid mixing chamber 45, so that the liquid material LM contained in the gas-liquid mixture is reduced in pressure. The liquid material LM is vaporized instantaneously and can be vaporized efficiently and stably.
[0007]
[Problems to be solved by the invention]
However, in the conventional liquid material vaporizer, the gas-liquid mixing chamber 45 for mixing the liquid material LM and the carrier gas CG, and the liquid material LM in the gas-liquid mixture generated in the gas-liquid mixing chamber 45 are used. Since the nozzle portion 46 to be vaporized is formed in the main body block 41 whose temperature is adjusted, there is the following inconvenience. That is, for example, when vaporizing a low vapor pressure liquid material LM such as pentaethoxytantalum, it is necessary to increase the temperature of the liquid material LM in order to increase the vaporization amount. 41 needs to be heated to increase its temperature. However, members such as the piezo actuator 49 are not very heat resistant, and therefore the heating temperature of the main body block 41 is naturally limited, and as a result, the low vapor pressure liquid material LM cannot be efficiently vaporized. There are inconveniences.
[0008]
Further, when the liquid material LM is heated for a long time and its temperature is raised, the liquid material LM is thermally decomposed and further transformed (transformed) into a substance having a low vapor pressure. Thus, there is a disadvantage that clogging occurs and the solid matter is supplied as it is as a semiconductor manufacturing material.
[0009]
The present invention has been made in consideration of the above-mentioned matters, and an object of the present invention is to provide a liquid material vaporizer that can reliably vaporize a liquid material that easily undergoes thermal decomposition without causing thermal decomposition. Is to provide.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a liquid material vaporizer according to the present invention is supplied with a low vapor pressure liquid material and a carrier gas, and has a flow rate control function for mixing the liquid material with the carrier gas while controlling the flow rate of the liquid material. A gas-liquid mixing unit comprising a valve is provided, and the gas-liquid mixture generated in the gas-liquid mixing unit is discharged to the gas outlet path by passing through the nozzle unit, whereby the liquid material contained in the gas-liquid mixture Is a liquid material vaporizer configured to be mixed with a carrier gas to become a mixed gas and to flow through a gas outlet path,
The liquid material is vaporized by releasing the gas-liquid mixture from the gas-liquid mixing unit, which is provided independently of the gas-liquid mixing unit and introduced through a pipe line, from the nozzle unit and reducing the pressure. A vaporization section for deriving the gas generated by the above-described carrier gas to a gas outlet path, and the gas-liquid mixing section and the vaporization section are individually set in temperature, and the temperature of the vaporization section is It is set higher than the temperature of the gas-liquid mixing part,
The gas-liquid mixing section has a gas-liquid mixing chamber, a recess is formed on the upper surface of the gas-liquid mixing chamber, a liquid material introduction path is opened in the recess, and a recess is formed at the center of the recess. A valve seat that is slightly higher than that is formed, and a mixing groove in which one end of the carrier gas introduction path and the gas-liquid mixture outlet path is opened is formed in the valve seat, and the other end of the gas-liquid mixture outlet path is It is characterized by being connected in communication with a pipeline (claim 1).
[0011]
[0012]
In the liquid material vaporizer, a liquid material and a carrier gas are supplied, and a gas-liquid mixing unit comprising a control valve having a flow rate control function for mixing the liquid material with the carrier gas while controlling the flow rate of the liquid material, Since the vaporizing unit that vaporizes the liquid material in the gas-liquid mixture supplied from the mixing unit is separated, each of the gas-liquid mixing unit and the vaporizing unit can be maintained at a temperature state suitable for each. The liquid material can be vaporized in the optimum state.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the details of the present invention will be described with reference to the drawings. 1 to 3 show an embodiment of the present invention. First, FIG. 1 schematically shows the overall configuration of a liquid material vaporizer according to the present invention. In this figure, 1 is a gas-liquid mixing unit having a liquid flow rate control function, and 2 is this gas-liquid mixing unit 1. Is a vaporization unit that is provided independently of the liquid material and vaporizes the liquid material contained in the gas-liquid mixture supplied via the conduit 3.
[0014]
The gas-liquid mixing unit 1 is composed of a control valve having a liquid flow rate control function and is configured as follows. That is, in FIGS. 2 and 3, reference numeral 4 denotes a rectangular parallelepiped main body block made of a material having high heat resistance and corrosion resistance, such as stainless steel. Three flow paths 5, 6, 7 are formed inside the main body block 4.
[0015]
The flow path 5 introduces a low vapor pressure liquid material LM into a gas-liquid mixing chamber 14 to be described later. The liquid material introduction path 5 has one end opened on the front side of the main body block 4 and the other end. Has an L shape so that it opens into the recess 15 on the upper surface of the main body block 4. A liquid material supply path (not shown) is connected to the liquid material introduction path 5 via a joint member 8 so that the liquid material LM whose flow rate is adjusted can be supplied.
[0016]
The flow path 6 introduces the carrier gas CG into the gas-liquid mixing chamber 14. One end of the carrier gas introduction path 6 opens on the right side of the main body block 4 and the other end of the main body block 4. It has an L shape so as to open on the upper surface. A carrier gas supply path (not shown) is connected to the carrier gas introduction path 6 via a joint member 9 so that the carrier gas CG whose flow rate is adjusted can be supplied.
[0017]
The flow path 7 leads out the gas-liquid mixture generated in the mixing groove 17 in the gas-liquid mixing chamber 14, and one end (upper end) of the gas-liquid mixture lead-out path 7 is the mixing groove 17. The other end (lower end) is connected to the conduit 3 inserted into the body block 4.
[0018]
Further, reference numeral 10 denotes a heater for heating the entire body block 4, which is composed of, for example, a cartridge heater. In the illustrated example, the insertion of the conduit 3 inserted into the body block 4 and connected to the gas-liquid mixture outlet passage 7. It is comprised so that a part can be heated.
[0019]
Next, the configuration of the upper surface 4a of the main body block 4 will be described with reference to FIGS. 2 and 3. Reference numeral 11 denotes a valve block, and an appropriate sealing member (not shown) is provided on the upper surface 4a of the main body block 4. And made of a material having good thermal conductivity and corrosion resistance, such as stainless steel. A valve body 12 having a liquid flow rate control function is formed between the valve block 11 and the upper surface 4a. That is, the gas-liquid mixing chamber 14 is formed in the internal space 11 a of the valve block 11 by the diaphragm 13 and the upper surface 4 a of the main body block 4.
[0020]
That is, the gas-liquid mixing chamber 14 is configured as follows, for example. A concave portion 15 is formed in the upper surface 4 a, and a vertical portion 5 a of the liquid material introduction path 5 is opened in the concave portion 15, and a valve seat 16 slightly higher than the concave portion 15 is formed in the center of the concave portion 15. The valve seat 16 is formed with a mixing groove (substantially gas-liquid mixing chamber) 17 in which the vertical portion 6 a of the carrier gas introduction path 6 and the vertical portion 7 a of the gas-liquid mixture outlet path 7 are opened.
[0021]
The diaphragm 13 is made of a material having good heat resistance and corrosion resistance and appropriate elasticity, and a valve portion 13b that contacts or separates from the upper surface of the valve seat 16 is formed below the shaft portion 13a. The thin wall portion 13c is provided around the thin wall portion 13c, and the thin wall portion 13c is provided with a thick wall portion 13d. However, when a downward pressing force is applied to the shaft portion 13a, the valve portion 13b is configured to displace in the direction in which the valve seat 16 abuts.
[0022]
Reference numeral 19 denotes an actuator for pressing the diaphragm 13 downward to displace it. In this embodiment, the piezoelectric element is formed by laminating a plurality of piezoelectric elements in a housing 20 erected on the top of the valve block 11. A stack 21 is provided, and a piezo actuator is configured such that a pressing portion 21 a below the piezo stack 21 is brought into contact with the upper end of the shaft portion 13 a of the diaphragm 13 via a true sphere 22.
[0023]
In the gas-liquid mixing chamber 14 having the above-described configuration, the liquid material LM that has passed through the liquid material introduction path 5 is introduced by the diaphragm 13 driven by the piezo actuator 19 while the flow rate into the mixing groove 17 is controlled. The carrier gas CG is introduced into the mixing groove 17 via the carrier gas introduction path 6. Then, the liquid material LM and the carrier gas CG are mixed in the mixing groove 17, led out to the gas-liquid mixture lead-out path 7 as a gas-liquid mixture GL, and further to the pipe 3.
[0024]
In FIG. 1, reference numeral 23 denotes a cover body of the gas-liquid mixing unit 1.
[0025]
Next, the configuration of the vaporizing section 2 will be described with reference to FIGS. 2 and 3. Reference numeral 24 denotes a vaporizing block 24a and a preheating block 24b. The vaporizing block 24a is heat and corrosion resistant like stainless steel. The preheating block 24b is made of aluminum having a high thermal conductivity. And in the preheating block 24b, one end is provided so that the other end side of the pipe line 3 inserted and connected to the main body block 4 of the gas-liquid mixing unit 1 penetrates. Further, the most downstream end of the pipe line 3 is Connected to the gas outlet path 25 in the vaporization block 24 a, a nozzle portion 26 is formed between the gas outlet path 25 and the most downstream end of the pipe 3. The vaporization block 24a incorporates a cartridge heater 27 and is heated so that the entire vaporization block 24a including the nozzle portion 26 has an appropriate temperature (a temperature considerably higher than the heating temperature of the main body block 4). It is designed to keep warm. Further, a pipe line (not shown) to the semiconductor manufacturing apparatus is connected to the downstream side of the gas outlet path 25 via a joint member 28.
[0026]
The nozzle portion 26 has a considerably small diameter and length, for example, a diameter of 1.0 mm or less and a length of about 1.0 mm. The gas-liquid mixture GL introduced through the pipeline 3 flows to the nozzle portion 26. At this time, the liquid material LM contained in the gas-liquid mixture GL is vaporized by being decompressed, and this vaporization causes The generated gas is mixed with the carrier gas CG to become a mixed gas KG.
[0027]
The pipe line 3 connecting the gas-liquid mixing unit 1 and the vaporizing unit 2 also has a function of preventing the temperature of the vaporizing unit 2 from being transmitted to the gas-liquid mixing unit 1 side. It also has a function of introducing the gas-liquid mixture GL generated on the one side into the vaporizing section 2 in as short a time as possible. For this reason, the inner diameter of the pipe line 3 is formed to be larger than the nozzle part 26, and a heater may be wound around the outer periphery of the pipe line 3 so as to be heated and held at an appropriate temperature.
[0028]
The operation of the liquid material vaporizer configured as described above will be described. The liquid material LM introduced into the gas-liquid mixing unit 1 through the liquid material introduction path 5 is introduced by controlling the inflow flow rate into the mixing groove 17 in the gas-liquid mixing chamber 14 by the diaphragm 13 driven by the piezo actuator 19. On the other hand, the carrier gas CG is introduced into the mixing groove 17 through the carrier gas introduction path 6. Then, the liquid material LM and the carrier gas CG are mixed in the mixing groove 17, led out to the gas-liquid mixture lead-out path 7 as a gas-liquid mixture GL, and reach the pipe 3.
[0029]
In this case, the main body block 4 in which the liquid material introduction path 5, the carrier gas introduction path 6, the gas-liquid mixture outlet path 7 and the mixing groove 17 are formed is heated and kept at an appropriate temperature by the heater 10. It is skillfully prevented that the liquid material LM is altered or a solid is generated. Further, since the pipe line 3 is also heated and kept at an appropriate temperature, the liquid material LM in the gas-liquid mixture GL is promptly introduced into the vaporizing section 2 through the pipe line 3 without being altered.
[0030]
The gas-liquid mixture GL introduced into the vaporization section 2 reaches the nozzle section 26 through the downstream end of the pipe 3 and further reaches the gas outlet path 25 through the nozzle section 26. The liquid material LM contained in the gas-liquid mixture GL is vaporized by depressurization, and the gas generated by this vaporization is mixed with the carrier gas CG to become a mixed gas KG, and in this state, a pipe line to the semiconductor manufacturing apparatus It flows to.
[0031]
In this case, the vaporizing section 2 is provided with a preheating block 24b, and the liquid material LM heading toward the nozzle section 26 through the pipe 3 is preheated. Further, since the vaporizing block 24a is heated and kept at an appropriate temperature by the heater 27, the nozzle portion 26 can efficiently vaporize the liquid material LM.
[0032]
As described above, in this embodiment, the liquid material included in the gas-liquid mixing unit 1 that mixes the liquid material LM and the carrier gas CG and the gas-liquid mixture GL supplied from the gas-liquid mixing unit 1. A vaporizing unit 2 for vaporizing LM is provided separately. Therefore, the temperature in the gas-liquid mixing part 1 and the vaporization part 2 can be set separately. That is, since the gas-liquid mixing unit 1 is provided with many members such as the diaphragm 13 and the piezo-actuator 19 whose heat-resistant temperature is not so high, the gas-liquid mixing unit 1 mixes the liquid material LM and the carrier gas CG. The temperature may be set and managed to such an extent that the liquid material LM is not thermally decomposed. On the other hand, in the vaporizing section 2, in order to carry out the vaporization of the liquid material LM efficiently the temperature of the vaporization blocks 24a and preheat block 24b, the optimum vaporization of the liquid material LM temperature (before crisis liquid mixing section 1 Temperature Higher).
[0033]
In addition, the heating of the liquid material LM can be shorter than in the prior art, and the liquid material LM can be vaporized instantaneously and stably in the vaporization unit 2. Foreign matter is not mixed.
[0034]
That is, in the liquid material vaporization apparatus having the above-described configuration, the liquid material LM can be efficiently vaporized without causing clogging of the liquid material LM or without causing the liquid material LM to be thermally decomposed and transformed. Gas can be obtained efficiently.
[0035]
【The invention's effect】
As described above, in the liquid material vaporization apparatus of the present invention, the gas-liquid mixing unit that mixes the low vapor pressure liquid material and the carrier gas, and the vaporization that vaporizes the liquid material in the mixed gas-liquid mixture. Since the gas-liquid mixing part and the vaporization part can be temperature-controlled so as to optimally perform their respective functions, the desired liquid material can be efficiently vaporized. Can do.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an overall configuration of an example of a liquid material vaporizer according to the present invention, in which (A) is a top view and (B) is a front view.
FIG. 2 is an enlarged cross-sectional view showing a configuration of a main part of the liquid material vaporizer.
FIG. 3 is a perspective view schematically showing a configuration of a main part of the liquid material vaporizer.
FIG. 4 is a diagram for explaining a conventional technique.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Gas-liquid mixing part (control valve), 2 ... Vaporization part, 3 ... Pipe line, 4a ... Upper surface, 5 ... Liquid material introduction path, 6 ... Carrier gas introduction path, 14 ... Gas-liquid mixing chamber, 15 ... Recessed part, 16 ... Valve seat, 17 ... Mixing groove, 26 ... Nozzle part, LM ... Liquid material, CG ... Carrier gas, GL ... Gas-liquid mixture.

Claims (1)

A liquid material having a low vapor pressure and a carrier gas are supplied, and includes a gas-liquid mixing unit including a control valve having a flow rate control function of mixing the liquid material with the carrier gas while controlling the flow rate of the liquid material. The generated gas-liquid mixture passes through the nozzle part and is discharged to the gas lead-out path. As a result, the liquid material contained in the gas-liquid mixture is vaporized by decompression, and this gas is mixed with the carrier gas. A liquid material vaporizer configured to be a mixed gas and flow through the gas outlet path,
The liquid material is vaporized by releasing the gas-liquid mixture from the gas-liquid mixing unit, which is provided independently of the gas-liquid mixing unit and introduced through a pipe line, from the nozzle unit and reducing the pressure. A vaporization section for deriving the gas generated by the above-described carrier gas to a gas outlet path, and the gas-liquid mixing section and the vaporization section are individually set in temperature, and the temperature of the vaporization section is It is set higher than the temperature of the gas-liquid mixing part,
The gas-liquid mixing section has a gas-liquid mixing chamber, a recess is formed on the upper surface of the gas-liquid mixing chamber, a liquid material introduction path is opened in the recess, and a recess is formed at the center of the recess. A valve seat that is slightly higher than that is formed, and a mixing groove in which one end of the carrier gas introduction path and the gas-liquid mixture outlet path is opened is formed in the valve seat, and the other end of the gas-liquid mixture outlet path is A liquid material vaporizer characterized by being connected in communication with a pipeline.

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