KR20080013447A - Vaporizer for liquid source - Google Patents

Abstract

A vaporizer for a liquid source is provided to improve vaporization rate and to prevent generation of particles by preventing generation of residues in the vaporizer. A liquid source is injected into a preliminary vaporizing portion(200). The preliminary portion vapors at least part of the liquid source. A main vaporizing portion(300) is connected to the preliminary vaporizing portion. The partially vaporized liquid source is moved along a flow channel and vaporized in the main vaporizing portion. An auxiliary vaporizing portion(400) is connected to the main vaporizing portion. A vaporization state of the vaporized liquid source is maintained in the auxiliary vaporizing portion. A heating device(500) heats at least part of the main vaporizing portion, the preliminary vaporizing portion, and the auxiliary vaporizing portion. A source supplying portion(100) supplies the liquid source and carrier gas. The source supplying portion includes a first supplying pipe(101) and a second supplying pipe(102). The first supplying pipe supplies the liquid source from at least one liquid supplying source. The second supplying pipe supplies the carrier gas from at least one carrier gas supplying source.

Description

Vaporizer for liquid source

1 is a schematic diagram for explaining an example of a CVD apparatus including a vaporization apparatus.

2 is a cross-sectional view of a liquid raw material vaporization apparatus according to an embodiment of the present invention.

3 is a cross-sectional perspective view of a liquid raw material vaporization apparatus according to an embodiment of the present invention.

4 (a) to 4 (c) are cross-sectional views of the inner guide pipe for explaining various embodiments of the flow path of the spiral groove of the liquid raw material vaporization apparatus according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: raw material supply unit 200: preliminary vaporization unit

300: main vaporizer 400: auxiliary vaporizer

500: heating device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid source vaporizer, and more particularly, to a liquid raw material vaporizer capable of improving vaporization rate and minimizing particles.

In general, in order to manufacture a semiconductor device or a display device, a desired device is manufactured by repeating a predetermined film forming process and an etching process on a substrate. Among them, the prescribed film forming process is becoming more stringent as the device is densified and highly integrated.

For example, very thin insulating films such as dielectric films and gate insulating films of capacitors are required in semiconductor devices. Moreover, thin film formation is calculated | required also about the film | membrane used for an electrode or a wiring. For example, a method of forming a copper film or an aluminum film by a chemical vapor deposition (CVD) process has been proposed. When the CVD process is applied using a liquid raw material, the liquid raw material is vaporized by a vaporization apparatus and supplied to the reaction apparatus to form a film. Therefore, in order to form a highly accurate film, the liquid raw material supplied to the vaporization apparatus must be vaporized efficiently and supplied to the reaction apparatus.

An example of a CVD apparatus including a vaporization apparatus is shown in FIG. 1. Referring to FIG. 1, a general CVD apparatus includes a liquid raw material vaporization apparatus 11, a liquid raw material supply source 12 to 15, a pressurizing tube 16, a liquid raw material flow control system 17 to 20, and a carrier gas supply tube 21. ), A carrier gas flow rate control system 22, a connecting pipe 23, and a reaction device 25. Each of the plurality of liquid raw material sources 12 to 15 is connected to the pressure pipe 16 and to the connecting pipe 23 via each of the liquid raw material flow control systems 17 to 20. The carrier gas supply pipe 21 is connected to the connection pipe 23 via the carrier gas flow control system 22. The connecting pipe 23 is connected to the raw material supply pipe 24 of the liquid raw material vaporization device 11. The raw material gas transport pipe 26 extending to the reaction device 25 side is connected to the liquid raw material vaporization device 11. In the reaction apparatus 25, a substrate heater (not shown) and the like are installed to heat and support the substrate.

The carrier gas flows from the carrier gas supply pipe 21 to the connection pipe 23 while the flow rate is regulated by the carrier gas flow control system 22. The liquid raw material inside the liquid raw material sources 12 to 15 is pressurized from the pressure tube 16 and regulated in a flow rate by the liquid raw material flow control system 17 to 20 to be supplied to the connecting pipe 23, and the liquid raw material vaporization device 11 Sprayed inside). The liquid raw material sprayed in the liquid raw material vaporization apparatus 11 is vaporized in the liquid raw material vaporization apparatus 11. The vaporized gas (raw material gas) passes through the inside of the source gas transport pipe 26 and is supplied into the reaction apparatus 25. The source gas forms a predetermined film on the substrate heated by the substrate heater (not shown) inside the reaction apparatus 25.

The vaporization apparatus for vaporizing the liquid raw material in the CVD apparatus is a predetermined space in which the liquid raw material is introduced and temporarily stored, the injection hole for injecting the stored liquid raw material, along the induction pipe and the induction pipe through which the liquid raw material injected through the injection port moves. And a heater installed outside the induction pipe for heating and vaporizing the moving liquid raw material.

However, in the conventional vaporization apparatus described above, since the heater is installed outside the induction tube, the liquid raw material is well vaporized at the inner contact surface of the induction tube, but less heat from the heater is provided at the center of the induction tube. As it is delivered, no vaporization of the liquid raw material occurs. This causes the liquid material that is not vaporized in the induction pipe to stagnate, which hinders the flow of the material in the induction pipe or the unvaporized liquid material is supplied to the chamber by pressure and deposited as impurities on the wafer.

In addition, due to the difference in the vaporization rate according to the position in the induction pipe, the flow rate of the raw material is high at the inner contact surface of the induction pipe, but the flow of the raw material is slowed at the center of the induction pipe, resulting in uneven flow rate for each position in the induction pipe. To prevent this, the liquid raw material flow controller must be used to constantly supply the liquid raw material into the vaporization apparatus. Even in this case, since the vaporization rate inside the induction pipe is nonuniform, the gaseous raw material supply to the chamber becomes nonuniform. Therefore, there is a problem that the uniformity and reproducibility of the formed film cannot be adjusted reproducibly because the raw material flowing into the chamber cannot be controlled reproducibly.

In addition, although the injection port is provided in the conventional vaporizer, the increase in the vaporization rate cannot be expected only by the injection port, and there is a problem in that deterioration of the vaporization device itself is caused by heating the liquid raw material to a temperature higher than necessary to increase the vaporization rate.

On the other hand, in the conventional vaporization apparatus, since the predetermined space in which the liquid raw material is stored has a right angle shape, the liquid raw material supplied through the supply pipe causes a vortex phenomenon near the edge of the predetermined space. Thus, the liquid raw material remains near the edge of the space, and adheres to the outer wall of the space as particles in the solid state. These particles again fall away from the outer wall and move along the induction tube with the liquid raw material, but are not vaporized and moved into the chamber in solid state to generate particles on the substrate.

An object of the present invention is to provide a liquid raw material vaporization apparatus that can improve the vaporization rate.

Another object of the present invention is to provide a liquid raw material vaporization apparatus capable of preventing particle generation by suppressing the generation of residues in the vaporization apparatus.

Liquid raw material vaporization apparatus according to an embodiment of the present invention is a liquid raw material is injected, a preliminary vaporization unit for vaporizing at least a portion of the liquid raw material; A main vaporization part connected to the preliminary vaporization part and vaporized while the partially vaporized raw material moves along a flow path; An auxiliary vaporization unit connected to the main vaporization unit and maintaining an evaporated state of the vaporized raw material; And a heating device for heating at least a portion of the main vaporizer and the preliminary vaporizer and the auxiliary vaporizer.

Further comprising a raw material supply for supplying the liquid raw material and the carrier gas.

The raw material supply unit, the first supply pipe for supplying the liquid raw material from at least one liquid raw material supply source; And at least one second supply conduit for supplying the carrier gas from at least one carrier gas source.

A connection pipe is further included between the liquid raw material supply source and the carrier gas supply source and the raw material supply part, wherein the first and second supply pipes are installed to have a smaller diameter than the connection pipe.

A portion of the first supply pipe and the at least one second supply pipe are connected to the first supply pipe, and the remainder of the second supply pipe is connected to the preliminary vaporization unit.

The preliminary vaporization unit includes a first space for storing the liquid raw material and the carrier gas supplied from the raw material supply unit.

The first space is formed in a shape in which the width of the first space is gradually increased from a portion connected with the raw material supply part and becomes constant at a predetermined position.

The main vaporization unit, the first injection port for injecting the raw material of the preliminary vaporization unit; A flow path through which the raw material injected through the first injection port is vaporized while moving; And a second injection hole for injecting the vaporized raw material while moving the flow path.

The flow path is formed as a spiral groove on the outer circumferential surface of the inner guide pipe.

Further comprising a first protrusion at one end of the inner guide tube, and further comprising a second protrusion at the end of the inner guide tube.

The second injection hole is formed with a diameter smaller than the diameter of the flow path.

The flow path is formed by installing an external induction pipe so as to be spaced apart from the internal induction pipe by a predetermined interval.

The auxiliary vaporization unit includes a second space for maintaining the vaporization state of the vaporized raw material introduced from the main vaporization unit.

The heating means is provided over the preliminary vaporization section, the main vaporization section and the auxiliary vaporization section.

The heating means comprises a plurality of cartridge heaters.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

2 is a cross-sectional view of a liquid raw material vaporization apparatus according to an embodiment of the present invention, Figure 3 is a cross-sectional perspective view.

2 and 3, the liquid raw material vaporization apparatus according to an embodiment of the present invention provides a raw material supply unit 100 and a supplied liquid raw material for supplying a liquid raw material and a carrier gas from a liquid raw material supply source and a carrier gas supply source. A preliminary vaporization unit 200 for partially vaporizing, a main vaporization unit 300 for vaporizing the liquid raw material while the liquid raw material moves along the flow path, and an auxiliary for maintaining the vaporized state of the vaporized raw material or vaporizing the unvaporized raw material The vaporizer 400 and the preliminary vaporizer 200, the main vaporizer 300 and the auxiliary vaporizer 400 is installed to extend the heating device 500 for heating the liquid raw material to vaporize or maintain the vaporized state It includes.

The raw material supply unit 100 may include a first supply pipe 101 for supplying liquid raw material from at least one liquid raw material source, and second and third supplies for supplying a carrier gas supplied at a constant pressure from the at least one carrier gas supply source. Feed tubes 102 and 103. Here, the first, second and third supply pipes (101, 102 and 103) is installed as a pipe having a diameter of 0.2 to 2.0 mm, the connecting pipe 110 for supplying the raw material to the vaporization device from the liquid raw material supply source and the carrier gas supply source 120 and 130) to make the flow rate of the liquid raw material and the carrier gas faster. In addition, the second supply pipe 102 is connected to each other at a predetermined position with the first supply pipe 101, the third supply pipe 103 is directly connected to the preliminary vaporizer 200. At this time, the raw material supply unit 100 may be manufactured integrally with the preliminary vaporization unit 200, it may be configured by connecting a separate microtube from the outside of the vaporization apparatus. In addition, in the connecting pipes 110, 120, and 130 for supplying the raw material, a region connected to the vaporization apparatus may be configured as a microtube.

The preliminary vaporization unit 200 includes a first space 201 for temporarily storing the liquid raw material supplied through the first supply pipe 101. In the first space 201, part of the liquid raw material is vaporized because the heating device 500 extends to a predetermined position. Therefore, the raw material of the liquid state and the gas state mixed in the 1st space 201 exists. On the other hand, the first space 201 is formed to have a width larger than the diameter of the first supply pipe 101 in order to sufficiently supply the liquid raw material through the first supply pipe 101, the portion connected to the first supply pipe 101 It is formed into a shape in which the width increases from and becomes constant at a predetermined position. For example, the width increases gradually from the entrance to the angle of 45 ° to 60 ° and is formed in parallel at a predetermined position. As the first space 201 is formed, the edges do not exist near the entrance as compared with the conventional case in which the first space 201 is formed at right angles. Thus, the vortex of the liquid raw material can be prevented, so that the liquid inside the first space 201 can be prevented. The raw material can be prevented from remaining. In addition, the third supply pipe 103 for supplying the carrier gas is connected to the first space 201 to supply the carrier gas to the first space 201. Accordingly, the liquid raw material in the first space 201 can be moved more smoothly. At this time, the preliminary vaporization portion 200 is composed of a cylindrical constant diameter portion having a constant diameter and the frontal conical region is gradually reduced in diameter, which is made of a material such as metal, for example, stainless steel. In addition, the heating device 500 extends adjacent to the boundary between the constant diameter portion and the frontal conical region.

The main vaporization unit 300 is the first inlet pipe 301 for injecting the mixed raw material stored in the first space 201, the internal induction pipe for moving the raw material of the mixed state injected from the first injection port 301 A flow path 303 of a plurality of spiral grooves formed on the outer circumferential surface of 302 and having a diameter of 0.2 to 2.0 mm, and an outer induction pipe 304 in which the outer circumferential surface and the inner circumferential surface of the inner guide pipe 302 are in close contact with each other. In addition, the first projection having a conical shape provided at one end of the inner guide pipe 302 to guide the stream of the mixed raw materials stored in the first space 201 in a streamlined manner to concentrate the first injection port 301. 305 is further included. The apparatus further includes a second conical second protrusion 306 provided at the end of the inner guide pipe 302, and the plurality of second injection holes formed by the second protrusion 306 is installed at the end of the internal guide pipe 302. 307 is further included.

The first protrusion 305 may be integrally installed with the inner guide pipe 302. The diameter of the first protrusion 305 is smaller than the diameter of the inner guide pipe 302 so that the inner guide pipe 302 and the first protrusion 305 may be installed. A predetermined step is made at the connection point of 305, and has a conical structure extending to the step. The first injection hole 301 is formed by fastening the outer guide tube 304 to the inner circumferential surface of the step, by fastening the fixing ring 308 in which a plurality of protrusions are formed. That is, the fixing ring 308 is fixed to the step, and since the protrusion of the fixing ring 308 fixes the first protrusion 305 of the inner guide pipe 302, the plurality of first injection holes 301 by the gap between the protrusions. ) Is formed. Here, the first injection hole 301 is formed to a diameter small enough to maximize the spraying effect, for this purpose adjusts the number and size of the protrusion of the fixing ring 308. In addition, the first injection hole 301 is connected to the flow path 303 of the spiral groove on the outer circumferential surface of the inner guide pipe 302.

As described above, the outer circumferential surface of the inner induction pipe 302 and the inner circumferential surface of the outer induction pipe 304 are in close contact with each other, and the flow path 303 of the helical groove is formed on the outer circumferential surface of the inner induction pipe 302 so as to be the first. The raw material of the mixed state injected through the injection hole 301 is moved. The liquid raw material which is not vaporized among the raw materials which are moved along the flow path 303 is heated and vaporized by the heating means 500 provided spaced apart from the external induction pipe 304 at predetermined intervals. Therefore, the longer the length of the passage 303 of the helical groove formed along the axis of the inner guide pipe 302, the longer the evaporation time, and the higher the evaporation efficiency. In addition, if the plurality of flow paths 303 of the spiral grooves are formed on the outer circumferential surface of the inner induction pipe 302 so as not to overlap, the vaporization efficiency can be further increased. On the other hand, as the material of the inner induction pipe 302 and the outer induction pipe 304, it is preferable to select a metal having excellent thermal conductivity, for example, stainless steel may be used.

In addition, a second protrusion 306 is installed at the end of the inner guide tube 302, the second protrusion 306 may be manufactured in a conical shape similar to the first protrusion 305. On the other hand, the second protrusion 306 is installed so that the stepped end is formed in the end of the inner guide pipe 302, it may be installed to be fixed to the stepped fixing ring formed with a plurality of protrusions on the inner peripheral surface. In this case, the first protrusion 305 is installed at one end of the inner guide pipe 302 and the fixing ring 308 having the protrusion formed on the inner circumferential surface thereof is fixed to the step so that the first injection hole 301 is formed. On the other hand, the second injection port 307 is formed by a thin tube having a diameter smaller than the first supply pipe 101 into which the liquid raw material is introduced, for example, a diameter of about 0.1 to 1.0 mm, so as to function as an orifice. Is vaporized while passing through the flow path 303 and the second injection hole 307.

The auxiliary vaporization unit 400 includes a second space 401 for perfect vaporization while maintaining a constant flow rate before supplying the vaporized raw material to the reaction chamber. The vaporized raw material injected through the second injection hole 307 is stored in the second space 401, and since the heating device 500 extends to a predetermined position, the vaporized state is maintained, and a very small amount of unvaporized liquid raw material is finally obtained. Vaporization by means of perfect vaporization. The vaporized raw material stored in the second space 401 is supplied to the reaction chamber through the discharge pipe 140.

The heating means 500 is installed over the preliminary vaporization unit 200, the main vaporization unit 300, and the auxiliary vaporization unit 400, and may use a plurality of cartridge heaters to further improve thermal conductivity. In addition, the heating means 500 is fastened to the body 520 by inserting a fixing screw in the fixing screw groove 510 provided in the body 520.

4 (a) to 4 (c) are cross-sectional views of the inner induction pipe, in which a plurality of spiral grooves separated from each other and parallel to the outer circumferential surface of the inner induction pipe may be formed in various shapes such as rectangles, rectangles, and triangles. . In addition, the shape of the spiral groove may be changed into a semicircular shape or the like, and the depth and width of the groove may be adjusted. The amount and speed of vaporization can be controlled by adjusting the shape, size and number of the flow path of the spiral groove.

The operation of the liquid raw material vaporization device of the present invention configured as described above is as follows.

The liquid raw material supplied from the liquid raw material source flows into the first space 201 through the first supply pipe 101. At this time, a carrier gas is supplied from at least one of the second and third supply pipes 102 and 103 to smoothly move the liquid raw material. The liquid raw material injected into the first supply pipe 101 and the carrier gas injected into the second or third supply pipe 102 or 103 are supplied to the first space 201 of the preliminary vaporization unit 200. At this time, since the heating device 500 extends to the first space 201, a part of the liquid raw material introduced into the first space 201 is vaporized, and the liquid state and the gas state are mixed in the first space 201. Raw material of will be stored.

Thereafter, the raw material filled in the first space 201 flows in a streamline form by the first protrusion 305 and is concentrated on the first injection hole 301, and the spiral of the main vaporization part 300 is passed through the first injection hole 301. The raw material is injected into the flow path 303 of the groove. As the raw material passes through the flow path 303 of the spiral groove, the raw material is heated by the heating device 500, thereby vaporizing the raw material.

Subsequently, since the second injection hole 307 is formed into a narrower tube than the first supply pipe 101, the raw material that has not been vaporized in the flow path 303 is not injected through the second injection hole 307 and the flow path 303 It stays within) and even vaporizes. The vaporized raw material is injected into the second space 401 through the second injection hole 307. The vaporized raw material supplied to the second space 401 maintains a constant flow rate and at the same time the heating means 500 is installed to extend to the second space 401 to maintain a vaporized state to achieve complete vaporization. . The vaporized raw material stored in the second space 401 is discharged into the reactor through the discharge pipe 140.

On the other hand, in the embodiment of the present invention has been described a case in which a plurality of spiral groove flow paths are installed on the outer circumferential surface of the inner induction pipe, and the outer circumferential surface of the inner induction pipe and the inner circumferential surface of the outer induction pipe are in close contact with each other. Instead, the inner induction pipe and the outer induction pipe may be maintained at a predetermined interval so that a flow path is formed therebetween.

As described above, according to the present invention, the first, second, and third supply pipes are provided with pipes smaller in diameter than the connecting pipes connecting the liquid raw material source and the carrier gas source and the vaporization device to increase the flow rate of the liquid raw material and the carrier gas. It speeds up and a carrier gas flows in simultaneously with a liquid raw material through the 2nd and 3rd supply pipe, and the movement of a liquid raw material is smoothed.

In addition, the heating device is extended to the first space for temporarily storing the liquid raw material so that a portion of the liquid raw material is vaporized in the first space, and the first space is formed in a shape that becomes wider from the entrance and becomes constant at a predetermined position. Thus, vortex of the liquid raw material in the first space can be prevented to prevent the generation of particles.

In addition, by forming a flow path of the helical groove along the inner circumferential surface of the inner guide pipe and heating it through a heating device, the vaporization rate can be increased compared to the length of the short inner guide pipe.

In addition, by installing the second injection port at the end of the inner guide pipe into a pipe having a diameter smaller than that of the first supply pipe, the liquid raw material which has not been vaporized is not sprayed and is completely vaporized.

On the other hand, the evaporation state can be maintained by extending the heating means even to the second space which makes the flow rate of the vaporized raw material injected through the second injection hole constant.

Therefore, according to the present invention, complete vaporization and particle generation of the liquid raw material can be minimized, thereby increasing the utilization efficiency of the liquid raw material, and easily forming high quality and high purity thin films.

Claims (15)

A preliminary vaporization unit into which a liquid raw material is injected and for vaporizing at least a portion of the liquid raw material; A main vaporization part connected to the preliminary vaporization part and vaporized while the partially vaporized raw material moves along a flow path; An auxiliary vaporization unit connected to the main vaporization unit and maintaining an evaporated state of the vaporized raw material; And And a heating device for heating at least a portion of the main vaporizer, the preliminary vaporizer, and the auxiliary vaporizer. The liquid raw material vaporization apparatus according to claim 1, further comprising a raw material supply unit for supplying the liquid raw material and the carrier gas. The method of claim 2, wherein the raw material supply unit, A first supply pipe for supplying the liquid raw material from at least one liquid raw material source; And And at least one second supply line for supplying the carrier gas from at least one carrier gas source. 4. The liquid according to claim 2 or 3, further comprising a connecting pipe between the liquid raw material supply source and the carrier gas supply source and the raw material supply part, wherein the first and second supply pipes have a smaller diameter than the connecting pipe. Raw material vaporization device. 4. The liquid raw material vaporization according to claim 1 or 3, wherein a part of the first supply pipe and the at least one or more second supply pipes is connected to the first supply pipe, and the remainder of the second supply pipe is connected to the preliminary vaporization part. Device. The liquid raw material vaporization apparatus according to claim 1, wherein the preliminary vaporization unit includes a first space for storing the liquid raw material and the carrier gas supplied from the raw material supply unit. 7. The liquid raw material vaporizing apparatus according to claim 6, wherein the first space is formed in a shape in which the width of the first space is gradually increased from a portion connected to the raw material supply portion and is constant at a predetermined position. The method of claim 1, wherein the main vaporizer, A first injection hole for injecting a raw material of the preliminary vaporization unit; A flow path through which the raw material injected through the first injection port is vaporized while moving; And And a second injection hole for injecting the vaporized raw material while moving the flow path. The liquid raw material vaporization apparatus according to claim 8, wherein the flow path is formed as a helical groove on an outer circumferential surface of the inner guide pipe. 9. The liquid raw material vaporization apparatus according to claim 8, further comprising a first protrusion at one end of the inner guide pipe, and a second protrusion at the end of the inner guide pipe. The liquid raw material vaporization apparatus according to claim 8, wherein the second injection hole is formed to have a diameter smaller than the diameter of the flow path. The liquid raw material vaporization apparatus according to claim 8, wherein the flow path is formed by providing an outer induction pipe so as to be spaced apart from the inner induction pipe by a predetermined distance. The liquid raw material vaporization apparatus according to claim 1, wherein the auxiliary vaporization unit includes a second space for maintaining a vaporization state of the vaporized raw material introduced from the main vaporization unit. The liquid raw material vaporization apparatus according to claim 1, wherein the heating means is provided continuously over the preliminary vaporization section, the main vaporization section, and the auxiliary vaporization section. The liquid raw material vaporization apparatus according to claim 1, wherein said heating means comprises a plurality of cartridge heaters.

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