JPH10229076A - Liquid material vaporizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform not only a mixture ratio but also concentration adjustment such as dilution, etc. SOLUTION: Since this vaporizer is arranged so as to collect a liquid material led out of containers 2A-2D and a solvent in one place through liquid-sending lines 4A, 4B, 4C, and 4D by providing this with the same container 2D, used exclusively for a solvent to receive the solvent as those used for liquid material in addition to material containers 2A, 2B, and 2C to receive the liquid material, it becomes possible to easily change not only the rate of the fellow liquid material but also the dilution, etc., through the quantity of led-out material, without removing the containers 2A-2D one by one.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid material vaporizing apparatus capable of suitably supplying a liquid material to a semiconductor manufacturing apparatus.

[0002]

2. Description of the Related Art In the manufacturing process of semiconductor devices, MoCVD has been widely used in recent years because it is superior to sputtering or the like in film quality, film forming speed, and step coverage. The gas supply method for CVD includes a bubbling method, a sublimation method, and the like, but in terms of controllability and stability,
A promising method is to dissolve the organic metal in a solvent and vaporize the organic metal immediately before the reaction layer.

[0003]

A conventional liquid material vaporizer for this purpose comprises a plurality of material containers for accommodating raw materials dissolved in a solvent and a feeder for collecting the liquid material from each container into one place. And a liquid line. However, in such a configuration, the mixing ratio between the raw materials can be changed by arranging a flow control valve or the like in the liquid feed line. It must be removed and the ratio of solvent to raw material must be changed. For this reason, the work is complicated, and this kind of liquid material is liquid at normal temperature and normal pressure, and handling is extremely complicated, such as hydrolysis when exposed to moisture in the atmosphere when the container is opened. It has become.

The present invention has been made in view of such a problem, and has as its object to provide a liquid material vaporizer in which not only the mixing ratio but also the concentration of a mixed solution can be easily changed.

[0005]

In order to achieve the above object, the present invention takes the following measures.
That is, the liquid material vaporizer of the present invention has a structure for mixing a plurality of liquid materials, a plurality of material containers for dissolving the liquid material in a solvent and containing the same, and the same or the same solvent as that used for the liquid material. It is provided with a dedicated solvent container filled with the same kind of solvent, and a plurality of liquid feed lines for collecting the liquid material and the solvent from each container at one place.

[0006] In such a case, the proportion of the solvent in the mixed solution, that is, the proportion of the raw material can be made variable by feeding an appropriate amount of the solvent from the container dedicated to the solvent.
Therefore, according to the present invention, it is possible to effectively adjust not only the mixing ratio but also the concentration such as the degree of dilution of the whole mixture without opening the inside of the container at all. in this case,
In order to perform mixing appropriately, it is preferable to dispose a mixer downstream of the collecting position of the liquid material and the solvent by each liquid sending line.

A vaporizer for vaporizing a liquid material or a solvent can be provided either upstream or downstream of the collecting position on the liquid sending line. In order to effectively purify the vaporizer, it is preferable to provide a solvent transfer line for directly introducing the solvent-dedicated container into the inlet of the vaporizer.

[0008]

An embodiment of the present invention will be described below with reference to the drawings. The liquid material vaporizer shown in FIG. 1 is for mixing, vaporizing and supplying a liquid material to a CVD reactor 1 which is a component of a CVD film forming apparatus.
B, 2C, a dedicated solvent container 2D, and a liquid sending line 4A,
B, 4C and 4D.

The material containers 2A, 2B, and 2C are filled with liquid materials A, B, and C in which raw materials are dissolved at a predetermined ratio using a common solvent. The raw materials of the liquid materials A, B, and C are, for example, P if a ferroelectric thin film is to be formed.
b, Zr, Ti, etc., Ba, Sr, Ti, etc. are used for forming a high dielectric thin film, and Bi, Sr, Cu, etc. are used for forming a superconducting thin film. Of course, it goes without saying that the number of material containers prepared according to the number of raw materials may be two or four or more.

The solvent dedicated container 2D is filled with the same solvent D as that used for the liquid materials A, B, and C. In this case, the solvents D are not necessarily the same as long as they do not chemically affect the CVD process, and the same type of solvent having the same property can be used. Liquid sending line 4A
4D are arranged such that one end is immersed in the liquid of each of the material containers 2A to 2C or the solvent dedicated container 2D, and the other end is gathered at the gathering position X, and each is upstream of the gathering position X. Flow rate adjustable proportional valves 5A, 5B, 5C,
5D is interposed. In this embodiment, the liquid supply line 4
A, 4B, 4C, 4D, and external supply lines 6A, 6
B, 6C, 6D, purge line 7, vacuum line 8
And the solvent bypass line 9 and the like share a pipe as much as possible and incorporate a number of valves (not shown) around the contact point of the pipe.
A, 4B, 4C, and 4D are sent from the containers 2A, 2B, 2C, and 2D to the collecting position X along arrows a1, b1, c1, and d1 in FIG.

The external supply lines 6A to 6D are provided with liquid materials A to D from the supply source (not shown) along the arrows a2, b2, c2 and d2 in FIG. C and solvent D are charged and replenished. The purge line 7 is for performing liquid level pressurization for sending liquid to each of the containers 2A to 2D, or for purging the inside of the containers 2A to 2D and the peripheral pipes. Figure 2
Along the middle arrow e for supplying an inert gas such as an unshown N ₂ and Ar in each container 2A-2D. When purging the inside of the pipe on the container inlet side and the inside of the container 2, an inert gas is introduced from the inert gas supply source to the container outlet side along the arrow f in FIG. Further, when purging the pipes on the container inlet side and the container outlet side, the proportional valves 5A to 5A through the container outlet side are directly passed from the container inlet side without passing through the container 2 along the arrow g in FIG.
The inert gas is supplied toward 5D.

The vacuum line 8 is used for evacuating the inside of the containers 2A to 2D and the surrounding pipes.
2D is evacuated by a vacuum pump (not shown) along the arrow h in FIG. 3 and FIG. By opening all the valves near each of the above-mentioned contacts, it is possible to evacuate all the piping upstream of the proportional valves 5A to 5D.

The solvent bypass line 9 is for cleaning the inside of a pipe located on the container outlet side. The solvent drawn out of the solvent exclusive container 2D along the arrow i in FIG. Can be transferred to In this case, the material containers 2A to 2C are evacuated using a vacuum line 8 as shown by an arrow h in the figure, and the solvent container 2D is pressurized by using a purge line 7 as shown by an arrow k in the figure.

In addition to the above structure, the liquid material vaporizer shown in FIG. 1 has a liquid feed pump 10 for controlling the flow rate, a mixer 11 for mixing the liquid,
A vaporizer 12 for vaporizing the liquid materials A to C, etc.,
The mixed gas that has passed through them is supplied to the CVD reactor 1. The pump 10 employs a high-precision, low-pulsation in-line type double plunger pump, and within the suction time when the plunger makes one stroke, each of the proportional valves 5A to 5D is set to a predetermined mixing ratio. The liquid material or the solvent is sequentially opened at appropriate distribution times so that the plunger sucks the liquid material or the solvent. The total flow rate is controlled through the driving speed of the liquid feed pump 10.

The solvent-only container 2D is designed so that the solvent can be directly transferred to the inlet of the vaporizer 12 through a solvent transfer line 13 and an auxiliary pump 14 separately provided for cleaning the vaporizer. It is also possible to introduce an inert carrier gas into the vaporizer 12 through the carrier gas introduction system 15 from outside. Next, the handling method of this embodiment will be described. First, when attaching empty containers 2A to 2D, their inlet side and outlet side are connected to the nearest pipes to which the containers 2A to 2D are to be connected, respectively, via joints z. Next, after opening all the valves to operate the vacuum line 8 and evacuating the containers 2A to 2D and the pipes at various locations, the liquid material is introduced into each of the containers 2A to 2D along arrows a2 to d2 in FIG. Fill AC and solvent D.
Then, while the pump 10 is operated, an arrow e in FIG.
When an inert gas is introduced into the inlet side of each of the containers 2A to 2D along the purge line 7 and pressurized at the liquid level, the liquid materials A to C and the solvent D filled in these containers 2A to 2D Are indicated by arrows a1 to d1 in FIG.
To 4D, and gather at the gathering position X at a predetermined mixing ratio via the proportional valves 5A to 5D. This mixing ratio can be changed through the setting of each of the proportional valves 5A to 5D even during operation. After the mixture thus produced passes through the pump 10 shown in FIG.
The mixture is homogeneously mixed by a mixer 11 and vaporized by a vaporizer 12. The vaporizer 12 is provided with a vent line 16 in addition to the CVD reactor 1, and the mixed gas is sent to the CVD reactor 1 only during the film formation as shown in the time chart of FIG. The space is released to the vent line 16 side. At this time, the pump 10 is turned off and the pump 14 is turned off.
N, the solvent is directly transferred from the solvent transfer line 13 to the vaporizer 12, and the inside is cleaned.

As described above, in this embodiment,
Through setting of the proportional valves 5A to 5D, not only the mixing ratio of each liquid material but also the ratio of the solvent in the mixed liquid, that is, the concentration of the raw material can be arbitrarily changed. Therefore,
According to this embodiment, the operation of the apparatus is stopped one by one and the containers 2A to
Without doing anything like removing 2D from joint z,
Dilution of the mixed solution can be performed very easily, and operation efficiency can be improved. In particular, recently, there is a demand to change the mixing ratio and the degree of dilution even during one film formation, and the apparatus of this embodiment can be extremely useful in meeting such a demand. In addition, the mixer 11 that has not been conventionally employed is located downstream of the collecting position X of each of the liquid sending lines 4A to 4D.
Is arranged, the mixing is homogenized in the mixer 11, and the quality of the mixed gas supplied to the film formation can be made extremely high to improve the film formation accuracy. In particular, depending on the material used, the vaporization temperature and the decomposition temperature approach each other, and the liquid material may remain in the vaporizer 12 to generate decomposition products. As shown in the chart, every time the film formation is completed, the vaporizer 12 is connected to the vent line 16 to introduce the solvent from the solvent supply line 13 and clean the inside, thereby effectively preventing generation of decomposition products. As a result, deterioration of the film quality can be prevented. Also, various pipes are commonly used for configuring each line, and a pump 10 and a vaporizer 1 for liquid sending are used.
Since each of the two is covered by one unit, advantages in cost and maintenance can be obtained through simplification of the overall configuration.

In addition to the handling described above, if the purge line 7 is formed as shown by the arrow g in FIG.
The liquid can be removed from the piping on the downstream side of the container while the liquid remains in D. If it is desired to remove all or a part of the containers 2A to 2D for liquid exchange or the like, the purge line 7 is connected to the position shown in FIG. If the vacuum line 8 is formed as shown by the arrow h and the vacuum line 8 is formed as shown by the arrow h, the liquid material and the like existing near the joint z of the containers 2A to 2D can be purged. In this case, if the liquid material remains in the pipe near the joint z, it may cause hydrolysis or the like. Therefore, while the liquid level in the solvent container 2D is continuously performed through the purge line 7 indicated by an arrow k in FIG. If the solvent is introduced into the material containers 2A to 2C through the solvent bypass line 9 indicated by the arrow i and the necessary piping is simultaneously evacuated through the vacuum line 8, it is possible to reliably prevent the liquid material from remaining. further,
When performing maintenance on the pump 10 and the valves 5A to 5C, the liquid level of the solvent container 2D is increased along the arrow m in FIG.
The solvent can be sent out to the peripheral piping along the arrow n.

The above embodiment is merely an example of handling, and it goes without saying that purging and evacuation in different modes can be performed through various opening and closing operations of the valve. Also, the specific configuration of each part is not limited to those in the illustrated embodiment, such as automatically controlling the valve or using a mass flow controller instead of the pump. Various modifications are possible.

[0019]

According to the present invention, as described above, in addition to the container for storing the liquid material, a solvent-only container for storing the same or the same type of solvent as that used for the liquid material is provided. The liquid material and the solvent derived from the container are collected at one place via a liquid sending line. Therefore, it is possible to easily change not only the ratio of each liquid material but also the degree of dilution thereof without removing the container one by one, and it is possible to effectively improve not only the operation efficiency but also the quality of film formation. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention.

FIG. 2 is an explanatory diagram of a main part of the circuit.

FIG. 3 is an explanatory diagram of a main part of the circuit.

FIG. 4 is an explanatory diagram of a main part of the circuit.

FIG. 5 is an explanatory diagram of a main part of the circuit.

FIG. 6 is an explanatory diagram of a main part of the circuit.

FIG. 7 is an explanatory diagram of a main part of the circuit.

FIG. 8 is a time chart showing an operation state of the embodiment.

[Explanation of symbols]

 A, B, C: liquid material D: solvent 2A, 2B, 2C: material container 2D: solvent-only container 4A, 4B, 4C, 4D: liquid sending line

Claims (1)

[Claims] An apparatus for mixing a plurality of liquid materials, comprising: a plurality of material containers for storing the respective liquid materials; and a same or similar type of solvent used for each of the liquid materials. A liquid material vaporizer comprising: a solvent-dedicated container filled with a solvent; and a plurality of liquid feed lines for collecting the liquid material and the solvent from each container at one place.