JPS61104636A - End station - Google Patents

Abstract

PURPOSE:To enable the equivalent reduction in time of evacuation of draw per wafer by a method wherein every carrier loaded with a plurality of wafers is subjected to vacuum rough draw in a carrying chamber. CONSTITUTION:After a carrier C1 loaded with a plurality of wafers W is carried into the carry-in chamber 20, this chamber 20 is drawn to rough vacuum by closing a gate valve 23, and the carrier is carried to a wafer take-out chamber 70 by opening a gate valve 24. After vacuum-draw of a processing chamber 60, the wafers W are taken out one by one and processed by ion implantation and the like, and the processed wafers are loaded to a vacant carrier C2 lying in a wafer load chamber 80; at the same time, the next carrier C1 stands by in the carry-in chamber 20. When all the wafers W are completed in processing, the carrier C1 which has become vacant is carried to a carry-out chamber 30 with an ascent-descent table 76, and the gas is leaked into the atmospheric pressure; then, the carrier is carried under the atmospheric pressure by opening then, the carrier is carried under the atmospheric pressure by opening a gate value 33. During the other carrying line, a carrier C2 loaded with the post- processing wafers W is carried to a carry-out chamber 50, and then carried out under the atmospheric pressure after gas leakage.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention transports a wafer in the atmosphere through a low-vacuum loading chamber to a high-vacuum processing chamber, where it is processed in a low-vacuum state after processing such as ion implantation. It relates to an end station that takes out air through an unloading chamber.

[Conventional technology]

FIG. 6 is a plan view schematically showing a conventional end station. This end station consists of one wafer transfer line and has a high vacuum (e.g. 10-5 to 10-7
41 (vacuum (e.g. I O-'
Loading room 1, which is a preliminary room for ~I O-"ro r r)
and an unloading room 3.

The loading chamber 11, the processing chamber 2, and the loading chamber 3G each have a vacuum exhaust system. Gate valves 4.5 are provided between the atmosphere and the loading chamber 1, between the loading chamber 1 and the processing chamber 2, between the processing chamber 2 and the unloading chamber 3, and between the unloading chamber 3 and the atmosphere.
．． 6.7 is provided, which allows one of the wafers W to be
Vacuum-tightness is maintained except during general transport. The wafer W is transported by the lines -8, 9, ]0.11, and ]2 for the first general feed.

FIG. 7 shows tie J and chart 1, which schematically show the operation of the apparatus shown in FIG. Was the wafer W placed in the atmosphere? ! Several wafers are loaded one by one into the loading chamber 1 from a carrier or another transfer line ((c) in the figure), and after the loading chamber 1 is evacuated (rough vacuum evacuation) ((d) in the figure). )) Processing room 2
((b) in the figure), and processes such as ion implantation are performed in the processing chamber 2 ((a) in the figure). Then wafer W
is transported to the first general unloading room 3 ((b) in the figure), and then to the unloading room 3.
After the gas leak, it became popular again (in the figure (C)
)).

Incidentally, an example of the above-mentioned end station is shown in '1 Shima Sho 57-205955.

[Problem that the invention seeks to solve]

In the end station described above, the wafer processing capacity (the number of wafers processed per unit time) is mainly determined by the processing chamber 2.
It is determined by the injection time for the loading chamber 1.1 and the vacuum IJI (rough vacuum pumping) time for loading the loading chamber 1.1 and the general discharge chamber 3. For example, when the wafer exchange time is 7 seconds, the processing capacity is about 200 wafers/hour when the injection time is 10 seconds, and the processing capacity is about 300 wafers/hour when the injection time is 5 seconds.

However, in recent years, with the large area and large current of ion beams, it has become possible to shorten the injection time (for example, 1 to 2 seconds), but with the end station described above, even if the injection time is 5 seconds or less, The processing capacity is mainly in the loading room 1,
It is very difficult to significantly improve the processing capacity, as it is limited by the rough vacuum evacuation time of the unloading chamber 3 (see Figure 7).
. In this case, making the roughing time very short means that ti+
The air system becomes huge and it is unrealistic in terms of space, rice, etc.

Therefore, it is an object of the present invention to solve the problem of roughing time being a bottleneck and to improve wafer throughput.

[Failure to solve the problem]

The en-1 station of the present invention has a first carrying-in chamber and a first carrying-out chamber each having a mechanism for transporting a first carrier capable of mounting a plurality of wafers, and a first carrying-in chamber and a first carrying-out chamber that are kept in a relatively high vacuum. A first carrier is received from the first general entrance chamber, and the wafers mounted thereon are taken out one by one and sent to the processing chamber, and the first carrier is transferred to the first general entrance chamber. A wafer unloading chamber having a mechanism for transporting a second carrier to the unloading chamber, a second loading chamber and a second unloading chamber each having a mechanism for transporting a second carrier onto which a plurality of wafers can be mounted, and It is maintained in a vacuum, receives a second carrier from the second loading chamber, loads wafers from the processing chamber thereon one by one, and transports the second carrier to the second unloading chamber. The wafer loading chamber has a wafer loading mechanism.

[Effect]

A plurality of wafers are mounted on a first carrier, and the first carrier is transported from the atmosphere to a wafer unloading chamber via a first general admission chamber. In the wafer unloading chamber, wafers are taken out one by one from the first carrier and transported to the processing chamber. On the other hand, for example, an empty second carrier is transported from the atmosphere to the wafer mounting chamber via the second general admission chamber. In the wafer mounting chamber, wafers from the processing chamber are mounted one by one onto the second carrier. The first carrier from which the wafer has been taken out is taken out into the atmosphere through the first unloading chamber, and the second carrier with the wafer mounted thereon is taken out into the atmosphere through the second unloading chamber. In this case, since rough vacuuming can be performed in the loading chamber for each carrier on which a plurality of wafers are mounted, the rough vacuuming time per wafer is reduced isometrically.

〔Example〕

FIG. 1 is a plan view schematically showing an embodiment of the present invention. This end station consists of one processing chamber and two carrier I delivery lines.

That is, this end station is placed under a low vacuum (e.g. 10
'~10-' Tor r
0, the wafer unloading chamber 70, and a high vacuum (for example) 0
-5 to 10-7 Torr) processing chamber 60 and a second processing chamber 60 of low vacuum (e.g. I O-' to 10-3 Torr).
It is comprised of a loading chamber such as a loading chamber 40, a second loading chamber such as a primary loading chamber 50, and a wafer mounting chamber 80.

The 1st general entrance chamber 20 is provided with a carrier 1 general conveyance belt 22 and gate valves 23, 24, and the 11th entrance section is provided with a gear rear transfer heald 21. 01 is brought in from the atmosphere and transported to the next room. Loading room 40 is also loading room 2
It has the same mechanism as 0, but for example, an empty 1' Yaria C2 to which a plurality of wafers W can be mounted is carried in from the atmosphere.

The unloading chamber 30 is provided with a carrier transport heald 32 and gate valves 33 and 34, and a
A carrier 1r & transport heald 31 is provided to receive the carrier C1 from the previous room and carry it out into the atmosphere. The unloading chamber 50 also has the same mechanism as the unloading chamber 30,
Receive carrier C2 from the previous room and carry it out into the atmosphere.

The wafer unloading chamber 70 and the wafer mounting chamber 80 are provided between the loading chamber 20 and the unloading chamber 30, and between the loading chamber 40 and the unloading chamber 50, respectively, and perform processing without using a gate valve or the like. It communicates directly with the chamber 60, thereby maintaining the same high vacuum as the processing chamber 60.

2 is an enlarged plan view schematically showing the wafer unloading chamber 70 shown in FIG. 1, and FIG. 3 is a side view taken in the direction 11-11 of FIG. Lifting table 76 L:t, lifted and lowered by a stomach descent mechanism (not shown). -1- Yaria transport healds 71 and 73 are; 1-Se fastest 1 general transport heald 22
and 32 are fixed at the same level.

The carrier conveyance heald 72 is raised and lowered by a -1-lower drive mechanism (not shown), and the gear rear conveyance heald in the digastric position is indicated by reference numeral 72, and the carrier conveyance heald in the lowered position is indicated by reference numeral 72'. -1- Seria 11 feeding heald 72 and carrier 1liff feeding heel [71 and 73
In this state, the carrier C1 is received from the 4-wheel conveyor belt 71 and is generally transported to the carrier conveyor heald 73. The carrier conveyance heald 72' in the lowered position is always located below the upper surface of the lifting table 76, and in this state, the carrier C1 is moved to the lifting table 76 in the shoulder position.
-Place it on the tray. The wafer transport heald 74 is located between the carrier 1 general transport heald 72 in the raised position and the lifting table 76 in the upper limit position, and is fixed at the same level as the wafer 1 general transport heald 61. In addition, the code 77 is installed on the lifting platform 76+)
This is the cutout.

FIG. 4 is a schematic diagram for explaining the function of the wafer unloading chamber. The initial position of the lifting platform 76 is the raised position. The carrier CI transported by the carrier 1 general transport heald 71 and the like is placed on the lifting platform 76 by lowering the carrier transport belt 72. In this state, the lifting platform 76
is lowered in stages, and the wafers W mounted on the carrier CI are taken out one by one by the woofer-fastest heald 74 and conveyed to the processing chamber 60. When all the wafers W have been taken out, the lifting table 76 is raised to the raised position, and the carrier (the fastest heald 72 is also raised to the raised position, and the empty carrier C1 is moved by the carrier transport hels 1 to 72.73). The wafer is transported to the unloading chamber 30.The position of the carrier C1, the presence or absence of the wafer W, etc. are detected by, for example, a photo sensor.

The wafer loading chamber 80 also has the same mechanism as the wafer unloading chamber 70, receives the empty carrier C2 from the II entry chamber 40, loads thereon one wafer W from the processing chamber 60, and loads a plurality of wafers W thereon one by one. The carrier C2 on which all of the wafers W have been mounted is transported to the unloading chamber 50. In this case, the lifting platform 8
The initial position of 6 is the lowering position, and the lifting table 86 is moved step by step to - each time the wafers W are loaded onto the empty carrier C2 one by one.
I feel angry.

Note that a mechanism for raising and lowering a carrier and taking out a wafer therefrom is shown in, for example, Japanese Patent Laid-Open No. 5F1214260.

The loading chamber 20.40, the loading chamber 30.50, and the processing chamber 60 each have an independent evacuation system.

However, for the rough vacuum system of the loading room 20.40 and the general exit room 30.50, the valves must be switched for rooms where the exhaust timings completely match, or for rooms where the exhaust timings do not overlap at all. Therefore, each can be shared. For example, the loading room 20 and the general entrance room 40, as well as the primary exit room 30 and the loading room 50, can be shared.

FIG. 5 shows tights, Char 1, showing an example of the operation of the apparatus shown in FIG. Such control is performed by a control means (not shown). In this case, the position detection of the carriers CI and C2, the position detection of the wafer W, the vacuum level detection of each room, etc. are carried out by a sensor installed at the end station.
The process is carried out at a vacuum level of 51 degrees.

An example of the operation of the present invention will be explained with reference to FIG. 5. First, the gate valve 24 is closed, nitrogen gas is introduced into the carry-in chamber 20 to cause the gas to leak to atmosphere j1, and the gate valve 23 is opened (in the figure) a)).

Then, the carrier CI loaded with a plurality of wafers W, for example, 25 wafers W, is carried into the carry-in chamber 20 ((1) in the figure). Thereafter, the gate valve 23 is closed and the loading chamber 20 is roughly cleaned, and when this is completed, the gate valve 24 is opened ((C)
)), the carrier C1 is generally transported to the wafer unloading chamber 70 ((d) in the figure).

Next, in step (e), the processing chamber 600 is evacuated, and the wafers W are taken out one by one from the carrier C1 and transported to the processing chamber 60, where processing such as ion implantation is performed, and the wafer mounting chamber 80 The sheets are loaded one by one onto the empty carrier C2 that is waiting. In this case, the ion beam comes from an ion source (not shown) perpendicular to the plane of the paper in FIG. 1, but it may also come in parallel to the plane of the paper if the wafer W is made to stand up. Also, during the processing of the wafer W,
The next gear rear C1 loaded with unprocessed wafers W is waiting in the loading chamber 20. When all the wafers W have been processed, the lifting table 76 is moved to the upper position ((f) in the figure).
The empty carrier CI is transported to the first general discharge room 30 ((g) in the figure). Then, close the gate valve 34 and
The gate valve 33 is opened ((h) in the figure), and the carrier CI is sent into the atmosphere ((I) in the figure). Then, the gate valve 33 is closed and the one-shell extraction chamber 30 is rough-hulled, and when that is completed, the gate valve 34 is opened and the system waits for the next operation ((j) in the figure.
)). On the other hand, a similar operation is being performed in parallel on the other carrier transport line, and the carrier C2 carrying a plurality of processed wafers W is transferred to the unloading chamber 50! It is transported ((p) in the figure) and released into the atmosphere after a gas leak ((r) in the figure).

In this way, in this end station, roughing is performed in the loading chamber 20 or the like for each carrier C1 on which a plurality of wafers W, for example, 25 wafers W are mounted. Therefore, compared to a conventional loading room where only one wafer W is loaded, the volume occupied by one wafer W in the most crowded room is estimated to be less than 1/2, and as a result, The isometric roughing time per sheet is also reduced to 1/2 or less. Therefore, the throughput, which was limited by the roughing time in conventional equipment, is significantly improved in the present end station. For example, in FIG. 5, if the ion implantation time for - wafers is 2 cycles, the entire process (e) for processing 25 wafers will take about 90 seconds, and the period T will last about 120 seconds. Since 25 wafers are processed during this time, the processing capacity is 75,050 wafers, which is a high processing capacity.

In addition, this end station has a loading room and a
Since the gas can be leaked very slowly in the general release chamber, the phenomenon of air hammer caused by the incoming air is prevented, thereby preventing breakage and damage to the wafer. Moreover, the wafer after processing is cooled in the wafer mounting chamber 80 until all mounting is completed, and gas leaks slowly in the unloading chamber 50.
The cooling time can be very long, at least several times longer than conventional equipment. Furthermore, unlike the conventional end station in which wafers are transferred one by one, the number of times the gate valve is opened and closed and the vacuum operation is controlled can be significantly reduced, thereby reducing the causes of failure.

In addition, in the description of -1-, the carrier C2 is generally fed once in the opposite direction to the carrier C1, but the carrier C2 is not limited to this, and the carrier C2 may be sent lla in the same direction as the carrier C1. In that case, the room 50 becomes the loading room and the room 40 becomes the general exit room. Furthermore, the transport of one carrier 01.02 and the transport of the wafer W are not limited to the carrier 1 as described above, but may be performed using rollers, chains, gears, or the like.

〔Effect of the invention〕

According to this invention, like IJ I-1
- Isometrically shorten the vacuum roughing time resulting in Uj deviation
This greatly increases wafer processing capacity!
- I can do it all the time.

[Brief explanation of drawings]

FIG. 1 is a plan view schematically showing an embodiment of the present invention.
It is. Figure 2 shows the wafer TfY unloading chamber in Figure 1.
FIG. 3 is an enlarged plan view showing approximately
It is a side view taken in the l1l-Tll force direction of the figure. Figure 4 1
, f, and 1 are schematic diagrams for explaining the function of the extraction chamber. FIG. 5 is a time chart 1 showing an example of the operation of the apparatus shown in FIG. FIG. 6 ζJ is a plan view schematically showing a conventional end station. FIG. 7 shows tie J and chart 1, which schematically show the operation of the apparatus shown in FIG. W...Wafer, C1, C2,, carrier, 20°4
0... Loading room, 30.50... 1 General exit room, 60.・
2 processing room, 70.1. Wafer unloading room, 80.0. Wafer mounting room

Claims (1)

[Claims] (1) An end station where a wafer in the atmosphere is transported through a relatively low-vacuum loading chamber to a relatively high-vacuum processing chamber, and after being processed there, it is taken out into the atmosphere through a relatively low-vacuum loading chamber. , a first loading chamber and a first unloading chamber each having a mechanism for transporting a first carrier onto which a plurality of wafers can be mounted, and a first loading chamber that is maintained at a relatively high vacuum. from 1st
a wafer unloading chamber having a mechanism for receiving the carrier, taking out the wafers mounted thereon one by one and conveying them to the processing chamber, and conveying the first carrier to the first unloading chamber; a second carrying-in chamber and a second carrying-out chamber each having a mechanism for transporting a second carrier capable of mounting one wafer;
an end station comprising: a wafer mounting chamber having a mechanism for receiving a carrier, mounting wafers from the processing chamber thereon one by one, and transporting the second carrier to a second unloading chamber; .