JPH053174A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To provide a wafer processing method where wafers are set uniform in processing condition from first, where the wafer processing method is that chambers which carry out wafer processing separately are employed, and wafers are successively transferred to the chambers from loaders through a common wafer transfer means and finally housed in unloaders. CONSTITUTION:Provided that a time required for transferring a wafer is represented by t, the number of chambers is N, and the wafer processing time of each chamber is represented by Ti, the residence time T of each wafer in the chamber is set to a certain value to satisfy formulas, T>tXN, T > maximum Ti, and a time, T-Ti, of each chamber is defined as a waiting time of a wafer, and a processing procedure is so constituted that a following wafer is transferred to a first chamber when a first wafer is transferred to a following chamber from a first chamber. In a figure, 1-5 denote the processes of a first to a fifth wafer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device, and more particularly, to a plurality of wafers which are sequentially subjected to a series of wafer treatments which are sequentially performed using a plurality of chambers for individually performing wafer treatments. Regarding the method of the occasion.

[0002]

2. Description of the Related Art In recent years, in a wafer process for manufacturing a semiconductor device, the wiring is becoming a laminated wiring in which an Al or Al alloy single layer is stacked on top of TiN and an Al alloy is stacked with the increase in integration density. Along with this, a sputtering apparatus used for forming a wiring film is becoming a multi-chamber apparatus including a plurality of chambers for individually performing wafer processing.

FIG. 2 is a block diagram of an example of the above multi-chamber apparatus. In the figure, 1a to 1d are chambers, 2 is load, 3 is unload, and 4 is wafer transfer means.

Each of the four chambers 1a to 1d is a chamber for carrying out wafer processing (sputtering) individually, and wafers are loaded and unloaded by the wafer transfer means 4. The load 2 is a portion for supplying unprocessed wafers, a wafer carrier storing a plurality of unprocessed wafers is set, and the wafer is unloaded to the wafer transfer means 4.
Done by

The unload 3 is a part for accommodating the wafers which have been processed by the chambers 1a to 1d, and the wafer transfer means 4 carries the wafers in. The wafer transfer means 4 is, for example, one robot arm, and is commonly used for the load 2, the chambers 1a to 1d, and the unload 3 to transfer the wafers to and from each other.

If one wafer is focused on, it is transferred from the load 2 to the chamber 1a → processing by the chamber 1a → transfer from the chamber 1a to the chamber 1b → chamber
Processing by 1b → Transfer from chamber 1b to chamber 1c
→ Processing by chamber 1c → Chamber 1c to chamber
Transfer to 1d → Processing by chamber 1d → Chamber 1d
Then, the unloading 3 is carried, and a series of wafer processing is completed.

From this, this multi-chamber apparatus is
After the preceding wafer is transferred to the chamber 1b, the next wafer is transferred to the vacant chamber 1a, so that the above-mentioned series of wafer processes are sequentially performed with respect to a plurality of wafers, that is, a time lag occurs. It can be given in the form of holding and performing parallel processing.

The above-mentioned conventional operation is performed in the chambers 1a to 1d.
In any of the above, the principle was to transport the wafer there to the next location when the wafer processing was completed. However, the first wafer from load 2 can obey the principle unconditionally, for example, if the processing time of chamber 1b is longer than that of chamber 1a,
For the second and subsequent wafers, since the chamber 1b is closed when the processing by the chamber 1a is completed, the chamber 1b is closed.
There was a waiting time until the chamber 1b was emptied for the transfer to.

Since the wafer processing is sputtering, the temperature of the wafer is lowered according to this waiting time,
There was a difference in wafer temperature between the first and second wafers at the start of processing by the chamber 1b. The mode of change of the wafer temperature at the start of processing due to the waiting time is shown in FIG. It should be noted that the temperature decrease until the start of processing includes the temperature decrease during conveyance, but the conveyance time is the same for the first and second sheets.

As a result, the processing condition of the first wafer is different from that of the second and subsequent wafers. Therefore, conventionally, the first wafer is used when the unprocessed wafer is stored in the wafer carrier. The wafer was used as a dummy wafer, and the second and subsequent wafers under the same processing conditions were used as product wafers.

[0011]

However, interposing a dummy wafer is not desirable in terms of cost and work efficiency. However, based on the above principle, depending on the interrelationship of the processing times of the chambers 1a to 1d,
In some cases, you will have to use four dummy wafers.

Therefore, according to the present invention, in the method of manufacturing a semiconductor device, when a series of wafers are sequentially processed for a plurality of wafers by using the above-described multi-chamber apparatus, a dummy wafer is initially used. The purpose of the present invention is to provide a method for ensuring that the processing conditions are met from the first wafer without being processed.

[0013]

In order to achieve the above object, in the method of the present invention, a plurality of chambers for individually performing wafer processing are used, and the wafers are transferred from the loader to each of the chambers by a common wafer transfer means. When sequentially performing a series of wafer processing in which a plurality of wafers are sequentially transferred and finally stored in an unloader, the time required to transfer each wafer is t, the number of chambers is N, and the wafer processing of each chamber is With the time T _i , the time T for keeping the wafer in each chamber is set to a constant value larger than t × N and larger than the maximum of T _i , and the time T−T _i in each chamber is used as the waiting time. In the chamber, and when the first wafer is transferred from the first chamber to the next chamber, the next wafer is transferred to the first chamber. In the procedure, such as to convey to the server,
It is characterized in that the above-mentioned series of wafer processing is sequentially performed on a plurality of wafers.

[0014]

By setting the dwell time T as described above, the processing time T _{i of} each chamber is secured, and the wafer transport by the wafer transport means is always performed at the end of the dwell time T _i. The waiting time T-T _i in the individual chamber
Will be aligned to the first wafer for multiple wafers.

Therefore, the wafer temperature at the start of processing in each chamber can be made uniform for all the wafers, and the processing conditions can be made to be the same from the first wafer without using a dummy wafer at the beginning.

[0016]

FIG. 1 shows an embodiment of the method according to the present invention.
The time chart will be described. This embodiment is a case where the multi-chamber apparatus described above with reference to FIG. 2 is used.

Therefore, as described above, if attention is paid to one wafer, it is transferred from the load 2 to the chamber 1a → process by the chamber 1a → transfer from the chamber 1a to the chamber 1b → process by the chamber 1b → chamber 1b to the chamber Transfer to 1c → Process by chamber 1c → Transfer from chamber 1c to chamber 1d → Process by chamber 1d → Transfer from chamber 1d to unload 3 A series of wafer processing is completed. Needless to say, all the wafers are conveyed by the common wafer conveying means 4 during this period.

In FIG. 1, symbols (1) to (5) show the time points of transfer and retention in the chambers 1a to 1d after the first to fifth wafers, respectively, starting from transfer from the load 2 to transfer to the unload 3. Over. Further, t is a time required for transporting each wafer, T is a time for keeping the wafer in each of the chambers 1a to 1d, and T _i is each chamber 1a.
Wafer processing time ~1d, T-T _i is the individual chambers 1a
In 1d, the waiting time for waiting the wafer after the wafer processing.

In this embodiment, as described above, by carrying out the procedure of carrying the preceding wafer to the chamber 1b and then carrying the next wafer to the chamber 1a, the above-mentioned series of wafer treatments are performed. The wafers are sequentially processed, that is, in parallel with a time lag, but the difference from the conventional case is that in the above operation,
In any of the chambers 1a to 1d, the wafer there is transported to the next location when the residence time T ends.

The residence time T is set to a constant value that is greater than the transfer time t × 4 (the number of chambers) and greater than the maximum of the processing time T _i , and is set to be the same for all the chambers 1a to 1d. As a result, all the chambers 1a to 1d have their respective processing times T _i secured, and in any case, the wafer transfer does not change the waiting time T-T _i of the individual chambers 1a to 1d. It can be carried out.

Therefore, the wafer temperature at the start of processing in each of the chambers 1a to 1d can be made uniform for all the wafers, and the processing conditions can be adjusted from the first wafer without using a dummy wafer at the beginning. You can And this means that the processing time T of the chambers 1a to 1d
_It holds regardless of the mutual relationship of _i .

Although the number of chambers is four in the above embodiment, it is apparent from the above description that the present invention is effective for any number of chambers.

[0023]

As described above, according to the present invention, a method for manufacturing a semiconductor device, and in particular, a series of wafer processes sequentially performed by using a plurality of chambers for individually performing a wafer process, is performed. Regarding the method for sequentially applying the above, a method is provided in which the processing conditions are adjusted from the first wafer without using the dummy wafer at the beginning, and the dummy wafer is used to adjust the processing conditions of the product wafer. This has the effect of eliminating defects in terms of cost and work efficiency due to the intervening conventional method.

[Brief description of drawings]

FIG. 1 is a time chart of an embodiment.

FIG. 2 is a block diagram of an example of a multi-chamber device.

FIG. 3 is a diagram showing changes in wafer temperature due to waiting time at the start of processing.

[Explanation of symbols]

1a to 1d Chamber 2 Loader 3 Unloader 4 Wafer transfer means 1st to 5th wafers elapsed t t Time required to transfer individual wafers T Time to retain wafers in individual chambers Ti _i Individual chambers Wafer processing time T-T _i Waiting time for waiting wafers in individual chambers

Claims (1)

Claim: What is claimed is: 1. A plurality of chambers for individually processing wafers are used, a wafer is sequentially transferred from a loader to each of the chambers by a common wafer transfer means, and finally stored in an unloader. When sequentially performing the wafer processing of a plurality of wafers, the time required for transporting each wafer is t, the number of chambers is N, and the wafer processing time of each chamber is T _i. time is the residence T set with a fixed value than the maximum larger and T _i from t × N, the wafer is waiting in the chamber a time T-T _i in individual chambers as latency, the first wafer is first When the next wafer is transferred from one chamber to the next chamber, the next wafer is transferred to the first chamber. A method of manufacturing a semiconductor device, wherein a plurality of wafers are sequentially processed.