JPH09199427A - Single-wafer processing of wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for processing wafers by which all the wafers can be processed as real ones without using dummy wafers, etc., when a single- wafer semiconductor manufacturing device is started up or re-started after it is temporarily stopped. SOLUTION: This is a method for single-wafer processing of wafers. When a single-wafer semiconductor manufacturing device wherein a wafer is processed in a heating atmosphere in a reaction chamber 6 is started up or re-started after it is temporarily stopped, a first wafer 40 is set in the reaction chamber 6 and then it is taken out of the reaction chamber 6 without being processed after the temperature distribution is stabilized. The wafers from a second one on are serially set and processed in the reaction chamber 6. The first wafer which has been taken out of the reaction chamber 6 is cut in between the wafers after the second one and is processed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer processing method in a single wafer type semiconductor manufacturing apparatus such as a single wafer low pressure CVD apparatus for processing a wafer in a reaction chamber under a heating atmosphere.

[0002]

2. Description of the Related Art An example of a single wafer type semiconductor manufacturing apparatus is shown in FIGS. FIG. 3 is a plan view showing an outline of a single-wafer type low pressure CVD apparatus, and FIG. 4 is a cross-sectional view taken along the line AA of FIG. In the figure, 1 is a transfer chamber, 2 is a transfer robot, 3 and 4 are cassette chambers, 5 and 6 are process chambers (reaction chambers), 30 is a wafer, and 34 is a cassette.

Two cassette chambers 3, 4 and two process chambers 5, 6 are connected to the side surface of the transfer chamber 1. Inside the transfer chamber 1, there is provided a transfer robot 2 for transferring wafers between the cassette chamber and the process chamber, and between the transfer chamber 1 and the cassette chambers 3, 4 or the process chambers 5, 6, The gate valves 9, 10, 11 and 12 respectively partition the gates. Cassette lifter 33 provided inside the cassette chambers 3 and 4
A cassette 34 is set on the upper side, and the wafer 30 is stored in the cassette 34. A susceptor 41 made of carbon is provided inside the process chambers 5 and 6, and the wafer 40 is set thereon. A temperature detector 46 for detecting the internal temperature is arranged inside the process chambers 5 and 6, and a quartz glass window 45 is provided at the ceiling of the process chambers 5 and 6, and the quartz glass window 45 is provided. Above the 45, the process chamber 5,
An infrared lamp 43 for heating the inside of 6 is arranged. The output of the temperature detector 46 is sent to the control device 37, and the output control of the infrared lamp 43 is performed by the control device 37.
Done by

Using this equipment, the wafers are roughly processed as follows. The transfer robot 2 extracts the wafer 30 from the cassette 34 in the cassette chamber 3 (or 4), transfers it into the process chamber 6 (or 5), sets it on the susceptor 41, and sets it on the infrared lamp 43 in a predetermined manner. After heating to the temperature, a reaction gas is supplied into the process chamber 6 (or 5) to form a thin film on the wafer surface. After the processing is completed, the transfer robot 2 is used again to transfer the wafer 40 to the original cassette 34 in the cassette chamber 3 (or 4).
Collect inside.

In the single-wafer type semiconductor manufacturing apparatus, when the wafer is processed as described above, conventionally, the wafer 30 is loaded from the cassette 34 of the cassette chamber 3 (or 4) in order from the top or the bottom. It was taken out, set in the process chamber 6 (or 5), and sequentially processed. When processing is performed in such an order, the temperature inside the process chamber is lowered when the apparatus is started up or restarted after a temporary stop, so it is necessary to raise the temperature to a predetermined temperature to stabilize it. Therefore, it is common practice to heat the inside without setting the wafer in the process chamber and set the wafer in the process chamber to start the process after the internal temperature has sufficiently stabilized. There is.

However, when the wafer is set and the processing is started, the presence of the wafer causes a slight difference in the temperature distribution of the components inside the process chamber 6. Therefore, the processing result of the first wafer and the process result. It has been found that a difference appears in the processing results of the second and subsequent sheets that are subsequently performed without significantly lowering the temperature inside the chamber 6. That is, even if the temperature inside the process chamber 6 is raised in a state where no wafer is present and once stabilized, the state of the heat flow inside the process chamber 6 changes due to the loading of the wafer. Even if the values measured by the temperature detector 46 for control are the same, the temperature distribution inside the process chamber 6 varies depending on the presence or absence of the wafer 40. Therefore, the first wafer set in the process chamber 6 heated in an empty state and having a stable temperature, and the second wafer set in the process chamber 6 in the state after the preceding wafer is taken out. Subsequent wafers have a slight difference in temperature distribution,
The processing result is affected.

In order to deal with such a problem, a method of heating and raising the temperature inside the process chamber 6 to stabilize the internal temperature in a state where the wafer is set from the beginning is also adopted, but in the case of this method, There is a difference in thermal history between the second and subsequent wafers loaded to the place where the temperature in the process chamber 6 is already close to the predetermined temperature. The effect appears in.

Therefore, conventionally, when the apparatus is started up, a dummy wafer is used as the first wafer, and the second and subsequent wafers are subjected to regular processing or adjustment. Another dummy wafer dedicated cassette is provided, and the first wafer is processed by taking out the dummy wafer in this cassette and processing it.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a single-wafer semiconductor manufacturing apparatus at the time of starting or temporarily stopping the apparatus. It is an object of the present invention to provide a wafer processing method capable of processing all wafers as regular wafers without using dummy wafers or the like when restarting later.

[0010]

The wafer single-wafer processing method of the present invention is a wafer processing method in a single-wafer semiconductor processing apparatus in which a wafer is processed in a reaction chamber in a heating atmosphere. When starting up or restarting after a temporary stop, set the first wafer in the reaction chamber,
After the temperature distribution in the reaction chamber has stabilized, the first wafer is removed from the reaction chamber without being processed, and the second and subsequent wafers are sequentially set in the reaction chamber and processed. The first wafer extracted in step 1 is characterized in that the processing is performed by interrupting the order between the processing of the second and subsequent wafers.

When the above-mentioned single-wafer processing method is adopted, the first wafer set in the reaction chamber for stabilizing the temperature inside the reaction chamber is not processed but is temporarily
Pull out of the process chamber and allow to cool. After the temperature of the first wafer has dropped to a level equivalent to that of the second and subsequent wafers, the first wafer is processed. The order of processing the first wafer can be appropriately interrupted during the processing of the second and subsequent wafers.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION When a wafer is processed in a single wafer type semiconductor manufacturing apparatus shown in FIGS. 3 and 4 as an example, when a single wafer processing method according to the present invention is applied, a process chamber 6 ( Wafer 4 set in the reaction chamber)
A model diagram of heat energy received by 0 is shown in FIG. For comparison, a model diagram of the thermal energy received by the wafer when the conventional method is applied to the same device,
As shown in FIG. 1 and 2, the vertical axis represents the temperature measurement value by the temperature detector 46 in the process chamber 6, and the horizontal axis represents the elapsed time and the number of the wafer set in the process chamber 6. Further, the apparatus shown in FIGS. 3 and 4 is the same as the apparatus described in the section of the prior art, and thus the description thereof will be omitted.

As shown in FIG. 1, when the wafer single-wafer processing method according to the present invention is applied, the temperature distribution in the process chamber 6 is stabilized when the apparatus is started up or restarted after a temporary stop. For that purpose, first, the first wafer is set in the process chamber 6. After the temperature distribution in the process chamber 6 is stabilized, the first wafer is taken out of the process chamber 6 without being processed and is temporarily collected in the cassette 30 in the cassette chamber 3. Next, the second wafer is set in the process chamber 6 and regular processing is started. While the second wafer is being processed, the first wafer extracted earlier is allowed to cool in the cassette 30 and is cooled to the same temperature as the other wafers. For this first wafer,
After the processing of the second wafer is completed, the order is interrupted between the second wafer and the third wafer to perform regular processing (see FIG. 4).

The timing for interrupting the processing of the first wafer is not limited to the timing between the second and third wafers as in the above example, but the temperature of the first wafer may be interrupted. However, it may be determined in consideration of the time required to sufficiently reduce and stabilize, and the convenience of the operation of the apparatus for processing the third and subsequent wafers.

As shown in FIG. 1, the energy received by the first wafer during stabilization of the temperature distribution in the process chamber is E ₀ , and the energy received by the second wafer during normal processing is E. _2. Let E ₁ be the energy received by the _first wafer during the regular processing and E _n be the energy received by the _n-th wafer during the regular processing. , The following relationship holds.

E ₀ > E ₁ = E ₂ = E _n On the other hand, as shown in FIG. 2, after the first wafer is used for stabilizing the temperature distribution in the process chamber,
Subsequently, when the normal processing of the first wafer is started as it is, the relationship between the above energy values is roughly as follows.

E ₁ > E ₂ = E _{n As described} above, by applying the wafer single wafer processing method according to the present invention, the temperature in the process chamber before each wafer is set during normal processing. As a result of the distribution being equal and the thermal history being received by each wafer during processing being equal, there is no need to incorporate a dummy wafer into the first wafer or dispose of the first wafer as a nonstandard product.

[0018]

By applying the wafer single wafer processing method according to the present invention, in a single wafer semiconductor manufacturing apparatus, a dummy wafer or the like is used when the apparatus is started up or restarted after being temporarily stopped. Instead, all wafers can be processed as regular wafers. As a result, it is effective in improving the production efficiency of the device or improving the yield.

[Brief description of drawings]

FIG. 1 is a model diagram showing thermal energy received by a wafer set in a process chamber when a single wafer processing method of the present invention is applied.

FIG. 2 is a model diagram showing thermal energy received by a wafer set in a process chamber when a conventional single wafer processing method is applied.

FIG. 3 is a plan view showing an outline of a single-wafer type semiconductor manufacturing apparatus.

4 is a sectional view of an AA portion of the single-wafer type semiconductor manufacturing apparatus of FIG.

[Explanation of Codes] 1 ... Transfer chamber, 2 ... Transfer robot, 3, 4 ... Cassette chamber, 5, 6 ... Process chamber, 30 ... Wafer, 33 ... Cassette lifter, 34 ... Cassette, 37 ... Control device, 4
0 ... wafer, 41 ... susceptor, 43 ... infrared lamp, 45 ... a quartz glass window, 46 ... temperature detectors, E _n ... n-th wafer in the process chamber Energy received during processing.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Nobuo Kashiwagi 2068-3 Ooka, Numazu-shi, Shizuoka Pref.

Claims (1)

[Claims] 1. A method for processing a wafer in a single-wafer type semiconductor processing apparatus for processing a wafer in a reaction chamber under a heating atmosphere, wherein the first wafer is processed when the apparatus is started up or restarted after a temporary stop. After the temperature distribution inside the reaction chamber has stabilized, the wafers are removed from the reaction chamber without processing the first wafer, and the second and subsequent wafers are sequentially placed in the reaction chamber. The first wafer that is set and processed, and the first wafer that has been extracted earlier is processed by interrupting the sequence between the processing of the second and subsequent wafers. Leaf treatment method.