JP2584927Y2 - Ion implanter - Google Patents

Description

[Detailed description of the invention]

[0001]

In the present invention, when the number of wafers in one lot (the number of wafers) is smaller than the number of wafers in one batch (the number of batches), dummy wafers are present together with the wafers on the disk, so that the wafers can be used. The present invention relates to an ion implantation apparatus that performs an ion implantation process in batch units.

[0002]

2. Description of the Related Art Generally, a large current type ion implanter is
An ion implantation process (hereinafter, referred to as an implantation process) is performed for each batch by holding a wafer on a plurality of mounting portions evenly arranged on the outer peripheral portion of the disk. The above-mentioned disk rotates at a high speed and reciprocates and translates so that the wafer is positioned in the passage of the ion beam. Since the center of gravity coincides with the center of rotation, all wafers can be injected under the same conditions by stable rotation.

However, for example, in a test or a research, an injection process may be performed on a wafer smaller than the number of batches. When the disk is rotated in a state where the wafer does not exist in some of the mounting portions, the center of rotation of the disk is deviated from the center of rotation, resulting in unstable rotation. The injection process becomes difficult. Therefore, when the injection process is performed on a wafer smaller than the number of batches, the center of rotation of the disk and the center of rotation are brought into agreement by adopting a method in which a dummy wafer is present on the mounting portion where no wafer is present. ing.

By the way, in order for a dummy wafer to be present on a mounting portion where no wafer is present, it is necessary to make the total of the number of wafers and the number of dummy wafers (the number of dummy wafers) equal to the number of batches. Therefore, the conventional ion implantation apparatus determines the number of dummy wafers corresponding to the number of unprocessed wafers for each one-lot implantation process, and supplies the same number of wafers and dummy wafers as the number of batches to the disk. It has become.

More specifically, a case where the number of batches is thirteen and the number of wafers in one lot is two, three, one, and four will be specifically described.

First, as shown in FIG. 31, a cassette accommodating two wafers of the first lot is placed on a first stage 51, and a cassette is placed on a second stage 52.
A cassette accommodating the three wafers in the lot is placed. Then, as shown in FIG. 32, the two wafers of the first lot are taken out from the first stage 51 and temporarily stored in the buffer stage 53, and the 11 wafers from the dummy wafer stage 54 are taken out. The wafer is taken out and temporarily stored in the buffer stage 53. As a result, in the buffer stage 53, there are wafers and dummy wafers that match the number of batches (13) of the two wafers and the 11 dummy wafers.

[0007] As shown in FIG. 33, the first lot wafer and the dummy wafer are connected to a buffer stage 5.
3 to the first air lock chamber 55.
At the same time, three wafers of the second lot are taken out from the second stage 52, and the buffer stage 53
The ten dummy wafers are taken out from the dummy wafer stage 54 and temporarily stored in the buffer stage 53.

Next, as shown in FIG. 34, the first lot wafer and dummy wafer are transferred to the disk 56 from the first airlock chamber 55, and the first injection processing is performed. Further, the second lot wafer and the dummy wafer are transferred from the buffer stage 53 to the first wafer.
It is conveyed to the air lock chamber 55.

When the first ion implantation is completed, FIG.
As shown in FIG. 5, the first lot wafer and dummy wafer are transferred to the second airlock chamber 57, and the second lot wafer and dummy wafer are transferred from the first airlock chamber 55 to the disk 56. Then, the second ion implantation is performed. And
As shown in FIG. 36, at the time of the second injection processing, the first lot wafer and the dummy wafer are transferred from the second airlock chamber 57 to the first stage 51 and the dummy wafer stage 54, respectively, and the first lot injection is performed. The process will end.

[0010] Thereafter, as shown in FIG. 37, a cassette containing one wafer of the third lot is placed on the first stage 51. 38 to FIG.
As shown in FIG. 6, after the 12 dummy wafers are prepared on the buffer stage 53 so as to match the number of batches (13) by the same procedure as described above, a third injection process is performed. Subsequently, preparation for the fourth injection process is performed.

[0011]

However, in the above-described conventional ion implantation apparatus, the total number of wafers and dummy wafers existing on a disk is replaced every time one lot of implantation processing is performed, so that the number of wafers smaller than the number of batches is reduced. When the lot is continuously injected, there is a problem that the lot switching time is relatively long with respect to the number of wafers to be processed.

Accordingly, it is an object of the present invention to provide an ion implantation apparatus which can solve the above-described problem that occurs when a lot of wafers having a smaller number of batches is continuously implanted.

[0013]

According to a first aspect of the present invention, there is provided an ion implantation apparatus in which, when the number of wafers in one lot is smaller than the number of batches, a dummy wafer and a wafer are present on a disk. Thus, the wafer is injected in batches, and has the following features.

That is, the ion implantation apparatus compares the numbers of wafers of one lot before and after the next lot so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches on the disk. di with the case of greater than wafer number Request carrying the number to carry the number of dummy wafers equal to the difference between the wafer number when loading the wafer rear lots disk to disk
If the number of dummy wafers unloaded from the disc is zero, and the number of wafers in the previous lot is smaller than the number of wafers in the subsequent lot, the number of dummy wafers equal to the difference between the two wafers when loading the wafers of the subsequent lot onto the disk. the to disk together and seek out the number to carry-out from the disk
If the number of dummy wafers is zero, and the number of wafers in the previous lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers loaded into the disk and the number of dummy wafers Management means for setting the number of unloading to zero, and loading means for loading the dummy wafer of the number of loadings determined by the management means to the disk when the wafer is loaded into the disk;
When the wafer is unloaded from the disk, there is provided an unloading means for unloading the number of dummy wafers determined by the management means from the disk.

Further, the ion implantation apparatus of the present invention compares the wafer numbers of one lot before and after so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches on the disk. when when the number is larger than the wafer number of the rear lots Request carrying the number to carry the number of dummy wafers equal to the difference between the wafer number when loading the wafer rear lots disk to disk
In both cases, the number of dummy wafers unloaded from the disk was set to zero.
And, if the wafer number of the previous batch is smaller than the wafer number of the rear lots seek out number to carry the number of dummy wafers equal to the difference between the wafer number when loading the wafer rear lot disc from the disc With de
The number of dummy wafers loaded into the disk is set to zero, and if the number of wafers in the previous lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers loaded into the disk and the number Management means for setting the number of dummy wafers to be unloaded to zero, and loading means for loading the dummy wafer of the loading number determined by the management means to the disk when the wafer is loaded to the disk; and loading and unloading the wafer from the disk. And an unloading means for unloading the dummy wafers of the unloading number determined by the management means from the disk, wherein a plurality of lots of the wafers are stored in the same cassette and prepared.

[0016]

According to the first and second aspects of the present invention, the dummy wafers are determined on the basis of the number of wafers in one lot before and after, so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches on the disk. The number of imports and exports is determined. That is, the management means compares the number of wafers of one lot before and after, and if the number of wafers of the previous lot is larger than the number of wafers of the subsequent lot, the difference between the two numbers of wafers when loading the wafer of the subsequent lot into the disk. the number of dummy wafers obtains the carry number to carry the disk equal to
As well as the number of dummy wafers
B, if the number of wafers in the previous lot is smaller than the number of wafers in the subsequent lot, the number of wafers to be unloaded so that the number of dummy wafers equal to the difference between the two numbers of wafers is unloaded from the disk when the wafers of the subsequent lot are loaded into the disk. With asking
The number of dummy wafers loaded into the disk is set to zero, and if the number of wafers in the previous lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers loaded into the disk and the number of Is set to zero. Since dummy wafers are loaded and unloaded in accordance with the number of loadings and unloadings, it is clearer than in the conventional case that the total number of wafers and dummy wafers existing on a disc is replaced every time one lot of injection processing is performed. The number of imports and exports is reduced. This makes it possible for the ion implantation apparatus to suppress a relative increase in the lot switching time with respect to the number of wafers to be processed when continuously performing a lot injection process for a lot of wafers smaller than the number of batches. Become.

Further, according to the second aspect of the present invention, since a plurality of lots are prepared and accommodated in the same cassette, the time required to exchange the cassettes when preparing the wafer is reduced. It can also be shortened.

[0018]

[Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the ion implanter according to the present embodiment has a disk 6 for implanting a plurality of wafers in batches. The disk 6 rotates at a high speed and reciprocates and translates so that the wafer is positioned in the passage of the ion beam. A mounting portion corresponding to the number of batches is provided on the outer periphery of the disk 6. They are evenly distributed.

The above-mentioned disk is disposed in a target chamber in a high vacuum state, and a partition of the target chamber has a first air lock chamber 5 (load-in) for switching between a high vacuum state and an atmospheric pressure state in a short time. Means) and a second air lock chamber 7 (unloading means). As a result, the target chamber is provided with the first and second wafers.
By carrying in and out via the air lock chambers 5 and 7, a high vacuum state can be maintained even when a lot composed of a plurality of wafers is switched.

The above-mentioned first and second air lock chambers 5.7
On the atmospheric pressure side, first and second stages 1 and 2 on which cassettes accommodating wafers to be processed in lot units are mounted, a dummy wafer stage 4 provided with a refill dummy wafer, a wafer and A buffer stage 3 for temporarily storing a dummy wafer is provided. The first and second air lock chambers 5.7
Further, between the stages 1, 2, 3, and 4, a not-shown transfer device (a transfer device, a transfer device) is provided, and this transfer device is configured to transfer a wafer and a dummy wafer.

The wafer and a dummy wafer is transported by the transport device is such as transport number and the conveying timing is managed by the management means (not shown) based on the wafer number S _n-1 · S _n of one lot of back and forth It has become.

That is, the management means includes the number of batches T and the number of wafers S ₁ · S ₂ ···· S of each lot (1 to n lots).
_n-1 · S _n is stored. When the first lot of wafers is to be injected, the number of wafers S ₁ is subtracted from the number of batches T to determine the number of wafers a to be loaded into the disk 6, and then the wafers with the number of wafers S ₁ are loaded. Number a
And the dummy wafer is carried into the disk 6.

When the wafers of the n-th lot are subjected to the injection processing, the number of wafers S _n-1 of the ( _{n-1) -th} lot and n
It is adapted to compare the wafer number S _n of the lot first. Then, the number a of the dummy wafers carried into the disk 6 a
In the case of _{S n-1 -S n> 0} , while adapted to be determined from _{a = S n-1 -S n} , if the _{S n-1 -S n ≦ 0} , is the a = 0 It has become so. The number b of unloading of the dummy wafer from the disk 6 is expressed as S _n-1 −S _n ≧
In the case of 0, b = 0, while S
For _n-1 -S _n <0, is adapted to be determined from the _{b = S n -S n-1} .

In the above configuration, the operation of the ion implantation apparatus will be specifically described. The number of batches T is 13, and the number of wafers S ₁ , S ₂ , S ₃ , S of the _{first to} fourth lots
It is assumed that ₄ is 2, 3, 1, and 4.

First, as shown in FIG.
Then, a cassette containing two wafers of the first lot is placed on the second stage 2, and a cassette containing three wafers of the second lot is placed on the second stage 2. Then, as shown in FIG.
, Two wafers of the first lot are taken out and temporarily stored in the buffer stage 3.

Next, by subtracting the number of wafers S ₁ (2) from the number of batches T (13), the number a (11) of dummy wafers to be loaded into the disk 6 is obtained. Eleven dummy wafers are taken out from the dummy wafer stage 4 and temporarily stored in the buffer stage 3. As a result, in the buffer stage 3, a wafer having the number of batches T (13) and a dummy wafer exist with the two wafers and the 11 dummy wafers.

The first lot wafer and dummy wafer are transferred from the buffer stage 3 to the first airlock chamber 5 as shown in FIG. Also,
At the same time, three wafers of the second lot are taken out from the second stage 2 and temporarily stored in the buffer stage 3, and the first wafer of the (n-1) th lot is taken out.
The wafer number S ₁ (2 wafers) of the lot is compared with the wafer number S ₂ (3 wafers) of the second lot, which is the n-th lot. Then, in this case, S ₁ (two pieces) −S
_{Since 2} (3) <0, the number a of dummy wafers loaded into the disk 6 is changed from a = 0 to 0, and the number b of dummy wafers unloaded from the disk 6 is b = S ₂ (3
₁ ) -S1 (2) to be 1 sheet. As a result, the dummy wafer is not transported from the dummy wafer stage 4 to the buffer stage 3, and only the three wafers of the second lot are present.

Thereafter, as shown in FIG. 4, the first lot wafer and the dummy wafer are carried into the disk 6 from the first airlock chamber 5, and the first injection processing is performed. Further, the wafer of the second lot is transferred from the buffer stage 3 to the first airlock chamber 5.

When the first ion implantation is completed, FIG.
As shown in (2), two wafers of the first lot and one dummy wafer for which the unloading number b has been determined by the above-described determination are unloaded to the second airlock chamber 7. On the other hand, the wafer of the second lot is carried into the disk 6 from the first airlock chamber 5, and the second ion implantation is performed. Then, as shown in FIG. 6, at the time of the second injection processing, the first lot wafer and the dummy wafer are transferred from the second airlock chamber 7 to the first stage 1 and the dummy wafer stage 4, respectively. Is completed.

Thereafter, as shown in FIG. 7, a cassette accommodating one wafer of the third lot is placed on the first stage 1. Then, as shown in FIG. 8, three wafers of the third lot are taken out from the first stage 1 and temporarily stored in the buffer stage 3, and the second lot, which is the (n-1) -th lot The number of wafers S ₂ (three) of the eye is compared with the number of wafers S ₃ (one) of the third lot which is the n-th lot. In this case, since S ₂ (3 sheets) −S ₃ (1 sheet)> 0, the number a of dummy wafers loaded into the disk 6 is a = S ₂ (3 sheets) −S ₃ (1 ), And the number b of the dummy wafers carried out from the disk 6 is b =
The number is changed from 0 to 0. As a result, two dummy wafers are transported from the dummy wafer stage 4 to the buffer stage 3, and there are one wafer and two dummy wafers of the second lot.

Thereafter, as shown in FIG. 9, the third lot wafer and dummy wafer are transferred from the buffer stage 3 to the first airlock chamber 5. When the second ion implantation is completed, as shown in FIG. 10, the number b of unloading is determined to be zero by the above determination, so that only three wafers of the second lot are in the second airlock chamber. 7 will be carried out. Further, the third lot wafer and the dummy wafer are carried into the disk 6 from the first airlock chamber 5, and the third ion implantation is performed. Then, as shown in FIG. 11, the wafer of the second lot is transported from the second airlock chamber 7 to the second stage 2, and the injection processing of the second lot is completed.

Next, as shown in FIG. 12, a cassette containing four wafers of the fourth lot is placed on the second stage 2, and as shown in FIG. Will be stored temporarily. Then, the n-1 is a lot 3rd lots th wafer number S ₃ (1 sheets), a wafer number of 4 lots th S ₄ (4 sheets) n lots th and are compared, S ₃ (1 sheet ) -S
₄ (4) <0, the number a of dummy wafers carried into the disk 6 is changed from a = 0 to 0, and the number b of dummy wafers carried out of the disk 6 is S ₄ ( will be a three from four) -S ₃ (1 sheet). As a result, the dummy wafer is not transported from the dummy wafer stage 4 to the buffer
Only the four wafers in the lot are present.

Thereafter, as shown in FIG. 14, only the wafer of the fourth lot is transferred from the buffer stage 3 to the first airlock chamber 5. Then, when the third ion implantation is completed, as shown in FIG. 15, the number of carry-outs b is determined to be three as described above, so that one wafer of the third lot and three dummy wafers are used. Is carried out to the second airlock chamber 7, the wafers of the fourth lot are carried into the disk 6 from the first airlock chamber 5, and the fourth ion implantation is performed.
Thereafter, as shown in FIG. 16, the third lot of wafers and dummy wafers are transferred from the second airlock chamber 7 to the first stage 1 and the dummy wafer stage 4, and
The injection processing of the lot ends.

As described above, in the ion implantation apparatus of this embodiment, the number of incoming and outgoing dummy wafers is changed so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches T on the disk 6. the wafer number S _n-1 · S _n of the lot is adapted to determine based on. As a result, the ion implantation apparatus of the present embodiment
The number of loadings and unloading is clearly reduced as compared with the case where the total number of wafers and dummy wafers existing on the disk 6 is replaced every time one lot of injection processing is performed. Therefore, when a lot of wafers smaller than the number of batches is continuously injected, it is possible to suppress a relative increase in the lot switching time with respect to the number of wafers to be processed.

Embodiment 2 Another embodiment of the present invention will be described below with reference to FIGS. 17 to 30. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 17 shows an ion implantation apparatus according to this embodiment.
As shown in FIG. 3, a disk 6 provided in the target chamber and a first
Airlock chamber 5, second airlock chamber 7, and first and second stages 1 provided with a wafer to be processed
2, a dummy wafer stage 4 provided with a refill dummy wafer, and a buffer stage 3 for temporarily storing the wafer and the dummy wafer.

The wafers of the first and second stages 1 and 2 are prepared in a form accommodated in a cassette 8, as shown in FIGS. 29 and 30, for example. The cassette 8 has a storage unit having a number of stages equal to or larger than the number of batches. When a lot of wafers having a number of wafers smaller than the number of batches is continuously injected, the total number of wafers of successive lots is equal to the cassette 8. The wafers 9 of different lots are accommodated in the same cassette 8 within a range not exceeding the number of stages. In addition, cassette 8
As shown in FIG. 29, the wafer 9 may be accommodated with a space between the accommodating portions as shown in FIG.
As shown in FIG. 0, wafers of each lot may be mixed and accommodated.

The wafer 9 composed of a plurality of lots accommodated in the cassette 8 is stored in the accommodation section No. of the cassette 8. And Lot No. Are stored by the management means. Further, this management means is similar to the first embodiment,
The number S of wafers in one lot before and after the number of loaded and unloaded dummy wafers so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches T on the disk 6.
The _n-1 · S _n is adapted to determine based on.

In the above configuration, the operation of the ion implantation apparatus will be specifically described. The batch number T is 13, and the wafer numbers S ₁ , S ₂ , S ₃ , S of the _{first to} sixth lots
₄ · S ₅ · S ₆ are two, three, one, four, five, and a five.

First, as shown in FIG. 17, the cassette 8 of FIG. 29 containing the wafers of the first to fourth lots is placed on the first stage 1 and the second stage 2
Then, a cassette accommodating the wafers of the 5.6th and 6th lots is loaded. Then, as shown in FIG.
Two wafers of the first lot are taken out of the stage 1 and eleven dummy wafers are taken out of the dummy wafer stage 4 and the wafers corresponding to the batch number T (13) and the dummy wafers are temporarily stored in the buffer stage 3. Will be kept in a safe place.

As shown in FIG. 19, the wafer of the first lot and the dummy wafer are connected to the buffer stage 3 as shown in FIG.
From the first air lock chamber 5. At the same time, the third lot from the first stage 1
One wafer will be taken out. And n-
Number of wafers in the first lot, the first lot S ₁ (2)
And the number of wafers S ₂ (3
), Only the three wafers of the second lot are temporarily stored in the buffer stage 3.

Thereafter, as shown in FIG. 20, the first lot wafer and dummy wafer are carried into the disk 6 from the first airlock chamber 5, and the first injection processing is performed. In addition, the second lot of wafers is transported from the buffer stage 3 to the first airlock chamber 5, and three wafers of the third lot are taken out of the first stage 1 and temporarily transferred to the buffer stage 3. Will be stored. Then, the number of wafers S ₂ (three) of the second lot, which is the (n−1) -th lot, is compared with the number of wafers S ₃ (one) of the third lot, which is the n-th lot. The number a of the wafers carried into the disk 6 is changed from a = S ₂ (three) −S ₃ (one) to two, and the number b of the dummy wafers carried out from the disk 6 is changed from b = 0 to zero. Will be done.

Thereafter, as shown in FIGS. 21 to 28, the number of wafers S _n−1 · S _n before and after the sixth lot provided in the first stage 1 and the second stage 2 is compared. Thus, the number a of dummy wafers carried into the disk 6 and the number b of dummy wafers carried out of the disk 6 are obtained, and the total number of the wafers and the number of dummy wafers on the disk 6 becomes the number of batches T.
Wafers and dummy wafers are carried in and out.

As described above, in the ion implantation apparatus of this embodiment, as in the first embodiment, the number of dummy wafers to be loaded is set so that the total of the number of wafers and the number of dummy wafers becomes the number of batches T on the disk 6. And the number of unloading 1
Since it is determined based on the number of wafers S _n-1 · S _n of the lot, when continuously injecting lots with a number of wafers smaller than the number of batches, the lot number corresponding to the number of wafers to be processed is It is possible to suppress a relative increase in the switching time.

Furthermore, in this embodiment, as shown in FIGS. 29 and 30, a plurality of lots are accommodated in the same cassette 8, so that two cassettes 8
As a result, it is possible to inject 6 lots of wafers 9. Therefore, this ion implantation apparatus can shorten the time required for replacing the cassette 8 when preparing the wafer 9.

[0047]

As described above, the ion implantation apparatus of the first aspect compares the numbers of wafers of one lot before and after so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches on the disk. If the number of wafers in the previous lot is larger than the number of wafers in the subsequent lot, the number of wafers to be loaded is determined so that the number of dummy wafers equal to the difference between the two numbers of wafers is loaded into the disk when the wafers of the subsequent lot are loaded into the disk. Unloading of dummy wafer from disk
When the number of wafers in the previous lot is smaller than the number of wafers in the subsequent lot, the number of wafers is unloaded so that the number of dummy wafers equal to the difference between the two wafers is unloaded from the disk when the wafers in the subsequent lot are loaded into the disk. determine the number
Together with the number of dummy wafers loaded into the disc
If the number of wafers in the preceding lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers carried into the disk and the number of dummy wafers carried out of the disk are set to zero when the wafers in the subsequent lot are carried into the disk. Means, loading means for loading dummy wafers of the number of loadings determined by the management means when loading the wafer into the disk, and unloading determined by the management means when loading the wafer from the disk. And unloading means for unloading a number of dummy wafers from the disk.

Thus, dummy wafers are loaded and unloaded based on the number of wafers in one lot before and after so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches on the disk. It is possible to suppress the relative increase in the lot switching time with respect to the number of wafers to be processed, as compared with the case where the total number of wafers and dummy wafers existing on a disk is replaced for each injection process. .

Further, as described above, the ion implantation apparatus according to the present invention compares the numbers of wafers of one lot before and after so that the sum of the number of wafers and the number of dummy wafers becomes the number of batches on the disk. If the number of wafers in the previous lot is larger than the number of wafers in the subsequent lot, the number of wafers to be loaded is determined so that the number of dummy wafers equal to the difference between the two numbers of wafers is loaded into the disk when the wafers of the subsequent lot are loaded into the disk. Dummy wafer from disk
When the number of wafers to be unloaded is zero, and the number of wafers in the previous lot is smaller than the number of wafers in the subsequent lot, when loading the wafers of the subsequent lot to the disk, dummy wafers of the number equal to the difference between the two wafer numbers are unloaded from the disk. the carry-out the number of required
And the number of dummy wafers
If the number of wafers in the previous lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers loaded into the disk and the number of dummy wafers unloaded from the disk are set to zero when the wafers in the subsequent lot are loaded into the disk. Management means, at the time of loading the wafer to the disk, loading means for loading the dummy wafers of the number of loadings determined by the management means to the disk, and at the time of unloading the wafer from the disk, determined by the management means. And an unloading means for unloading the number of unloaded dummy wafers from the disk, wherein a plurality of lots of the wafers are stored in the same cassette and prepared.

Thus, in addition to the effect of the first aspect, since a plurality of lots of wafers are accommodated in the same cassette, the time required for exchanging cassettes when preparing wafers can be shortened. It works.

[Brief description of the drawings]

FIG. 1 illustrates one embodiment of the present invention, and is an explanatory diagram showing a state when wafers of the first and second lots are prepared in first and second stages.

FIG. 2 is an explanatory diagram illustrating a state when a first lot wafer is moved to a buffer stage.

FIG. 3 is an explanatory diagram showing a state when a first lot wafer is moved to a first airlock chamber.

FIG. 4 is an explanatory diagram showing a state when a first injection process is performed.

FIG. 5 is an explanatory diagram showing a state when a second injection process is performed.

FIG. 6 is an explanatory diagram showing a state when a wafer of a first lot is moved to a first stage.

FIG. 7 is an explanatory diagram showing a state when a wafer of a third lot is prepared on a first stage.

FIG. 8 is an explanatory diagram showing a state when a third lot wafer is moved to a buffer stage.

FIG. 9 is an explanatory diagram showing a state when a third lot wafer is moved to a first airlock chamber.

FIG. 10 is an explanatory diagram showing a state when a third injection process is performed.

FIG. 11 is an explanatory diagram showing a state when a wafer of a second lot is moved to a second stage.

FIG. 12 is an explanatory diagram showing a state when a wafer of a fourth lot is prepared in a first stage.

FIG. 13 is an explanatory diagram showing a state when the wafer of the fourth lot is moved to the buffer stage.

FIG. 14 is an explanatory diagram showing a state when a fourth lot wafer is moved to a first airlock chamber.

FIG. 15 is an explanatory diagram showing a state when a fourth injection process is performed.

FIG. 16 is an explanatory diagram showing a state when a third lot wafer is moved to a first stage.

FIG. 17 shows another embodiment of the present invention.
FIG. 9 is an explanatory diagram showing a state when wafers of a fourth lot and a 5.6 lot are prepared in first and second stages.

FIG. 18 is an explanatory diagram showing a state when a first lot wafer is moved to a buffer stage.

FIG. 19 is an explanatory view showing a state when the wafer of the first lot is moved to the first airlock chamber.

FIG. 20 is an explanatory diagram showing a state when a first injection process is performed.

FIG. 21 is an explanatory diagram showing a state when a second injection process is performed.

FIG. 22 is an explanatory diagram showing a state when the wafer of the first lot is moved to the first stage.

FIG. 23 is an explanatory diagram showing a state when a third injection process is performed.

FIG. 24 is an explanatory diagram showing a state when the wafer of the second lot is moved to the first stage.

FIG. 25 is an explanatory diagram showing a state when a fourth injection process is performed.

FIG. 26 is an explanatory diagram showing a state when the third lot wafer is moved to the first stage.

FIG. 27 is an explanatory diagram showing a state when a fifth injection process is performed.

FIG. 28 is an explanatory diagram showing a state when the wafer of the fourth lot is moved to the first stage.

FIG. 29 is an explanatory diagram showing a state in which a plurality of lots of wafers are accommodated in a cassette.

FIG. 30 is an explanatory diagram showing a state in which wafers of a plurality of lots are accommodated in a cassette.

FIG. 31 shows a conventional example, and is an explanatory view showing a state when wafers of the first and second lots are prepared in first and second stages.

FIG. 32 is an explanatory diagram showing a state when the wafer of the first lot is moved to the buffer stage.

FIG. 33 is an explanatory diagram showing a state when the wafer of the first lot is moved to the first airlock chamber.

FIG. 34 is an explanatory diagram showing a state when a first injection process is performed.

FIG. 35 is an explanatory diagram showing a state when a second injection process is performed.

FIG. 36 is an explanatory diagram showing a state when the wafer of the first lot is moved to the first stage.

FIG. 37 is an explanatory diagram showing a state when a wafer of a third lot is prepared in a first stage.

FIG. 38 is an explanatory diagram showing a state when the third lot wafer is moved to the buffer stage.

FIG. 39 is an explanatory diagram showing a state when the third lot wafer is moved to the first airlock chamber.

FIG. 40 is an explanatory diagram showing a state when a third injection process is performed.

FIG. 41 is an explanatory diagram showing a state when the wafer of the second lot is moved to the second stage.

FIG. 42 is an explanatory diagram showing a state when a wafer of a fourth lot is prepared in a second stage.

FIG. 43 is an explanatory diagram showing a state when the wafer of the fourth lot is moved to the buffer stage.

FIG. 44 is an explanatory diagram showing a state when the wafer of the fourth lot is moved to the first airlock chamber.

FIG. 45 is an explanatory diagram showing a state when a fourth injection process is performed.

FIG. 46 is an explanatory diagram showing a state when the third lot wafer is moved to the first stage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st stage 2 2nd stage 3 Buffer stage 4 Dummy wafer stage 5 1st air lock chamber (loading means) 6 Disk 7 2nd air lock chamber (loading means) 8 Cassette 9 Wafer

Claims (2)

(57) [Scope of request for utility model registration] 1. An ion implantation apparatus for ion-implanting wafers in batches by providing dummy wafers on a disk together with wafers when the number of wafers in one lot is smaller than the number of batches. Compare the number of wafers in one lot before and after so that the sum with the number of dummy wafers becomes the number of batches on the disk. If the number of wafers in the previous lot is larger than the number of wafers in the subsequent lot, the number of wafers in the next lot is changed. When loading the disk, the number of wafers to be loaded is set so that the number of dummy wafers equal to the difference between both
And the number of dummy wafers to be unloaded from the disk
If the number of wafers in the preceding lot is smaller than the number of wafers in the succeeding lot, the number of wafers to be taken out of the disc is equal to the difference between the two wafers when the wafers of the succeeding lot are carried into the disc. Ask for
In both cases, the number of dummy wafers loaded into the disk was zero.
If the number of wafers in the preceding lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers carried into the disk and the number of dummy wafers carried out of the disk are set to zero when the wafers in the subsequent lot are carried into the disk. Means, at the time of loading the wafer into the disk, loading means for loading the number of dummy wafers determined by the management means into the disk, and at the time of unloading the wafer from the disk, the loading determined by the management means. And an unloading means for unloading a number of dummy wafers from the disk. 2. A wafer prepared by a cassette.
When the number of wafers in the lot is smaller than the number of batches, the presence of the dummy wafers together with the wafers on the disk allows the ion implantation apparatus to perform the ion implantation process on the batches of the wafers, wherein the sum of the number of wafers and the number of dummy wafers is Is compared with the number of wafers in one lot before and after, so that the number of wafers in the preceding lot is larger than the number of wafers in the subsequent lot. The number of dummy wafers to be loaded into the disk is equal to the difference between the two wafers.
And the number of dummy wafers to be unloaded from the disk
If the number of wafers in the preceding lot is smaller than the number of wafers in the succeeding lot, the number of wafers to be taken out of the disc is equal to the difference between the two wafers when the wafers of the succeeding lot are carried into the disc. Ask for
In both cases, the number of dummy wafers loaded into the disk was zero.
If the number of wafers in the preceding lot is equal to the number of wafers in the subsequent lot, the number of dummy wafers carried into the disk and the number of dummy wafers carried out of the disk are set to zero when the wafers in the subsequent lot are carried into the disk. Means, at the time of loading the wafer into the disk, loading means for loading the number of dummy wafers determined by the management means into the disk, and at the time of unloading the wafer from the disk, the loading determined by the management means. An unloading means for unloading a number of dummy wafers from a disk, wherein the wafers are prepared by accommodating a plurality of lots in the same cassette.