JP2511845B2 - Processing equipment for vapor phase growth - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a large number of processes (sequences) in a processing chamber such as a vapor phase growth apparatus for epitaxially growing a semiconductor substrate and a diffusion apparatus for diffusing impurities. ) Is related to the processing device that needs to be processed.

[Technical background of the invention and its problems]

Conventionally, a semiconductor substrate such as silicon (hereinafter referred to as a wafer)
As a device used for so-called epitaxial growth for growing a crystal thin film having the same crystal orientation as that of a wafer, a device called a vertical vapor phase growth device, a horizontal vapor phase growth device, or a cylinder type vapor phase growth device has been put into practical use. There is. Although each of these devices has excellent features, it is desired to improve productivity, and the wafer diameter is being increased (5 inches and 6 inches). Increasing the size of the susceptor on which the wafer is placed (hence increasing the size of the reaction chamber) is in progress. However, increasing the size of the susceptor causes problems in the manufacturing technology of the susceptor, has limitations, and is expensive. Further, quartz parts such as a quartz bell jar constituting the reaction chamber also have to be upsized, and upsizing of the quartz parts is a serious problem because it is fragile and expensive.

Furthermore, as the characteristics required for the epitaxial layer,
Although the uniformity of the film thickness and the film resistance is an important point, it is difficult to reduce the variation within the batch with the increase in size.

Further, if the number of processed sheets for each batch is increased, if a trouble occurs during the processing, all the products in the batch become defective products and the damage is large. Furthermore, since explosive gas, corrosive gas, or toxic gas is used for epitaxial growth, it can be said that increasing the size is not preferable. Currently, susceptors with a diameter of about 900 mm can be supplied with SiC coating, but as a device, those using a susceptor with a diameter of 900 mm are not in operation. The largest commercially available by the present inventors is currently a susceptor with a diameter of about 700 mm. In this case, 19 "/ batch for 5" wafers and 10 "for 6" wafers.
Only single / batch processing is possible. Moreover, since the volume of the reaction chamber is large, it takes a long time to set the atmosphere in the reaction chamber to, for example, an N ₂ gas atmosphere, so that the total time required for one process is considerably long. Even if it were 60 minutes, it would only be possible to process 10 sheets at 6 ″ per hour.

Although the vapor phase growth apparatus has been described above as an example, the diffusion apparatus, the vapor deposition apparatus, the etching apparatus, and the like have substantially the same problem.

[Object of the Invention]

The present invention has been made by paying attention to the above circumstances, and an object thereof is to improve productivity, and further, to provide excellent processing uniformity such as processing chambers such as individual reaction chambers and gas and heat energy. It is another object of the present invention to provide a processing apparatus for vapor phase growth or the like in which the processing body supply means can be made small and inexpensive.

[Outline of Invention]

In order to achieve the above-mentioned object, in a processing apparatus such as vapor phase growth, a series of processing processes can be executed in units of the processing chambers, and a total time required for the series of processing processes is a predetermined time unit. Processing chambers of which the quotient is equal to or larger than the quotient, processing body supply means for gas, heat energy, etc., provided so as to be connectable to the respective processing chambers, and each processing A device for automatically loading and unloading a processing object into and from the processing chambers, and the processing body supply means for the respective processing chambers so that the sequence is executed in the respective processing chambers by sequentially shifting the time with reference to a predetermined time unit. In addition to controlling the supply from the chamber, the automatic loading and unloading device controls the loading and unloading of the object to be processed in each processing chamber in accordance with the execution of the sequence. Comprising the door, in which the treated article is to sequentially obtained from each processing chamber. That is, although each reaction chamber is a batch type, it is possible to continuously obtain wafers processed every predetermined time unit.

Example of Invention

Hereinafter, an embodiment in which the present invention is applied to a vapor phase growth apparatus will be described with reference to an embodiment. In FIG. 1, reference numeral ₁₁ denotes a reaction processing chamber, that is, a reaction chamber. The reaction chamber ₁₁ is composed of a base plate 2 and a quartz bell jar 3 ₁ mounted on the base plate 2 so as to be able to move up and down (open and close). Has been done. The aforementioned reaction chamber 1 _1, the susceptor 4 is provided on the susceptor 4 is placed is the wafer 5 to be processed thereof. The susceptor 4 is supported by the rotating shaft 6, the rotary shaft 6 is adapted to be given a rotation by the motor 9 ₁ via a gear 7 and 8.

Also, the bell jar 3 ₁ is connected to a gas supply pipe 10 _1, so as to supply the various gases necessary for vapor phase growth process such as purge gas and the reaction gas from the gas unit 12 via an on-off valve 11 ₁ Has become. A gas exhaust pipe 13 ₁ is connected to the base 2 and communicates with an exhaust gas processing unit (not shown) via an opening / closing valve 14 ₁ .

On the upper surface portion of the bell jar 3 _1, infrared lamp 15 ₁ for heating the wafer 5 and the susceptor 4 is provided,
Electric power is supplied from the heating unit 17 via the switch 16 ₁ . The power supplied to the wafer 5
Alternatively, it is controlled by the heating unit 17 according to the output from the temperature detector (not shown) of the susceptor 4.

On the base 2, similar to the bell jar and the bell jar 3 ₁
3 ₂ , 3 ₃ ... 3 _n are arranged on a straight line or a circle by the number described later. In each of the bell jar _{3 1, 3 2, 3 3} ... 3 n, the motor 9 ₁ similar motor 9 _2, and 9 ₃ ... 9 _n, closing valve 11 ₁ and the same on-off valve for the gas supply 11 ₂ , 11 ₃ … 11 _n , an on-off valve 14 ₂ similar to the on-off valve 14 ₁ for discharging gas, 14 ₃ … 14 _n , and an infrared lamp 15 ₂ , 15 ₃ … 15 _n and its switch 16 ₂ ,
16 ₃ ... 16 _n are provided respectively, and these are operated by the process control device 18.

Thus, when growing the vapor phase, together with the reaction gas is supplied from the gas supply pipe 10 ₁ into the reaction chamber 1 _1, it is heated by infrared lamps 15 _1, further susceptor 4 by the operation of the motor 9 ₁ Is rotated. The reaction gas supplied into the reaction chamber 1 ₁ is electronically excited to dissociated compound absorbs infrared rays, further, growing an epitaxial film on the wafer 5 by the heat energy of the heated wafer 5.

By the way, the number n of the reaction chambers 1 ₁ to 1 _n is determined by the selection of the sequence of the epitaxial growth process by the user, the number of wafers 5 that can be processed in _one reaction chamber 11 and the number of wafers to be produced in a predetermined time. To be done. That is, if the total time required for the epitaxial growth process is 30 minutes and 60 wafers 5 are to be processed per hour, one wafer 5 is processed in one reaction chamber and the predetermined time unit is 1 minute. Therefore, the number n of reaction chambers 1 is required to be 30.

Further, it decided to 30 seconds for a predetermined time units when processing 120 wafers 5 per hour, to the reaction chamber 1 ₁ may be the number n of 1 _n and 60.

When 20 wafers 5 are processed per hour, the predetermined time unit is 3 minutes, and the number n of reaction chambers is 10.

Here, one example of a general epitaxial process is shown, for example, as shown in Table 1 below, and the sequence No., the sequence name, and the sequence contents are displayed. Required time is the time when to no reaction chamber 1 ₁ for use in the present invention assuming a 1 _n.

For Table 1, decides to 1 minute for a predetermined time units, would be constituted by the total required time is 28 minutes for since 28 of the reaction chamber 1 ₁ to 1 _28.

Further, when the process shown in Table 2, decides to 1 minute for a predetermined time unit, composed of the total because the duration is 21 minutes 21 of the reaction chamber 1 ₁ to 1 _21.

In addition, the process shown in Table 3 shows how the sequence No. 2 and the sequence No. 3 are recognized when the predetermined time unit is set to 1 minute, and more than the predetermined time unit such as the sequence No. 9. It describes how to capture a short time sequence. That is,
It is sufficient to set the quotient obtained by summing the sequence Nos. 2 and 3 and dividing by the predetermined time unit to be an integer. The same applies to sequence No. 9. In addition, in Table 4, the predetermined time unit is 1
It consists of 28 reaction chambers, and it shows which sequence number is being executed in the current reaction chamber No. and which sequence number is being executed 1 minute later.

For example, the sequence No.1 SET is
If the reaction is currently performed in the No. 5 reaction chamber, one minute later indicates that it is being performed in the No. 6 reaction chamber.

Table 5 shows that when the epitaxial growth process is performed,
Si and other contaminants on the susceptor and in the reaction chamber can cause susceptor etching and
1 illustrates an example of a Si coating process.

In addition, Table 6 shows that if, for example, the No. 7 reaction chamber or No. 13 reaction chamber has failed, it must be repaired.
Preliminary reaction chamber so that o.7 or No.13 reaction chamber can be substituted
29 and 30 are provided so that when the repair is completed and the Ready signal is output, the reaction chambers of No. 7 and No. 13 are on standby until the next start time, and are incorporated into the normal process flow. Is.

Further, when the process of the susceptor etching and the Si coating described in Table 5 is incorporated into the epitaxial process of Table 4, it will be explained in Table 6. Table 6 shows that the reaction chamber Nos. 15, 16, 17, 18 are Since the four reaction chambers have become the etching process, it is explained that the reaction chambers No. 33, 34, 35, and 36 perform the epitaxial process on their behalf.

The reaction chambers 15, 16, 17, 18 are on standby after the etching process is completed, and when the epitaxial process is completed at 33, 34, 35, 36, the reaction chambers become the epitaxial process. Then, next, the etching process is sequentially performed in the four reaction chambers 19, 20, 21, 22 and the reaction chambers 19, 20, 21, 22 are replaced by 33, 34, 35, 36. That is, when performing the processes of susceptor etching and Si coating, there are reaction chambers above the above-mentioned roots, which is the same number of reaction chambers as performing the processes of susceptor etching and Si coating.

Table 7 illustrates an example in which the process shown in Table 5 for susceptor etching and Si coating is incorporated into the epitaxial process shown in Table 4. In this way, when another process enters, in a predetermined time unit,
Although it is not possible to obtain an epitaxial wafer in every predetermined time unit in the reaction chamber of the same integer as the quotient obtained by dividing the total required time, in order to obtain it, if the reaction chamber is provided based on the total required time of the two processes. Good.

Then, when the epitaxial growth was carried out using the vapor phase growth apparatus shown in FIG. 1 and the process and conditions as shown in Table 7 using the 5-inch wafer 5, the gross rate (growth rate) was 0.6 μm / min. , The variation of the film thickness distribution in the wafer 5 is ± 4%, the variation of the batch opening is ± 1.5.
A good result of% was obtained.

Incidentally, in the present invention, as it is conventional, rather than discontinuous batch process, has a constant continuous batch processing, the number of the reaction chamber 1 ₁ to 1 _n Many, even shorter predetermined time unit If it is not, the productivity is not improved, so that the loading and unloading of the wafer 5 is automatically performed by the automatic loading and unloading device.

Moreover, in gas control, as shown in FIG.
One reaction system may control all the reaction chambers 1 ₁ to 1 _n . For example, if there are 28 reaction chambers ₁₁ ..., 4 gas units or 7 gas units may be used. It may be controlled by a control system.

Similarly, the number of heating units is not limited to one, and a plurality of heating units may be switched. Further, as shown in FIG. 2, two wafers 5 may be set in the reaction chamber 21 and heated by using the high frequency induction heater 22 as a heating source.

As described above, in the case of the epitaxial growth apparatus which is practically used as the conventional apparatus, the batch processing is discontinuous, and the productivity is temporarily 60 minutes / batch.
With respect to 19 inch wafers, in the method of the present invention,
If the shortest time unit is 1 minute and the total required time is 30 minutes
It is clear that the productivity is drastically improved, 60 sheets / hour, compared to the conventional equipment.

Although the above-described embodiments have been described by taking the vapor phase growth apparatus as an example, the present invention is applied to various apparatuses such as a diffusion apparatus, a vapor deposition apparatus and an etching apparatus which perform processing processes from a large number of sequences in one processing chamber. be able to.

〔The invention's effect〕

As described above, according to the present invention, since one processing chamber can be made small, it is possible to shorten the time required to execute each sequence such as purging with N ₂ gas (N ₂ P). Viewed in units of one processing chamber, the total time required for the process can be significantly shortened to improve productivity, and the continuous structure of a predetermined time unit eliminates waste and improves productivity. It is possible to improve productivity by reducing

Further, adjustments may be made for each processing chamber in accordance with each processing chamber, and since management is performed for each small processing chamber, it is easy to make products uniform. In addition, expensive parts such as a quartz bell jar and a susceptor become cheaper as the size becomes smaller, and the problem of manufacturing equipment is eliminated.

Further, it is possible to deal with the object such as a wafer having a large diameter of, for example, 5 inches, 6 inches or 8 inches. Further, since the volume of the processing chamber becomes small, the purging time and the purging amount can be shortened, and further, the gas can be circulated or shared in the same sequence.

[Brief description of drawings]

FIG. 1 is a block diagram showing a processing apparatus for vapor phase growth which is an embodiment of the present invention, and FIG. 2 is a block diagram showing another embodiment. 1 ₁ to 1 _n ... Reaction chamber, 5 ... Object to be processed (wafer), 12 ...
Gas unit, 17 ... Heating unit, 18 ... Process control device.

Claims (6)

(57) [Claims] 1. In a processing apparatus such as vapor phase growth, a series of processing processes can be executed for each processing chamber, and the total time required for the series of processing processes is a quotient in a predetermined time unit. The number of processing chambers equal to or larger than the quotient when divided as described above, processing body supply means for gas, thermal energy, etc., which are provided so as to be connectable to the respective processing chambers, and objects to be processed for the processing chambers. The automatic loading and unloading device and the supply from the processing body supply means to each processing chamber are controlled so that the sequence is executed in each processing chamber sequentially with a predetermined time unit as a reference. Along with the execution of the sequence, the automatic loading and unloading device is provided with means for controlling loading and unloading of the object to be processed in each processing chamber. Processing apparatus such as a vapor deposition treated article from is characterized in that the sequentially obtained. 2. The vapor phase growth apparatus according to claim 1, wherein the processing apparatus is a vapor phase growth apparatus, and the processing body supply source is purge and reaction gas supply means and heating energy supply means. Processing equipment. 3. At least one pretreatment chamber is provided, and at the time of starting a process in each treatment chamber, a function of checking the previous process performed in the treatment chamber is provided, and the abnormal treatment is performed. The processing apparatus for vapor phase growth according to claim 1 or 2, characterized in that, when there is a chamber, the process is performed on behalf of the pretreatment chamber. 4. An abnormal processing chamber, having at least one or more preprocessing chambers, and having a function of checking the sequence performed in each processing chamber at the start of each sequence. In the case where there is any, the process is performed by the pretreatment chamber after the total time required for the process in the treatment chamber has passed, and the process such as the vapor phase growth according to claim 1 or 2 is characterized. Processing equipment. 5. A process according to any one of claims 1 to 4, wherein another special process is incorporated into the predetermined treatment process as a continuous sequence. Processing equipment for phase growth. 6. The special process is executed in a processing chamber for a predetermined processing process, and the predetermined processing process is executed in a preliminary processing chamber while the special process is executed. 5. A processing apparatus for vapor phase growth or the like according to claim 5.