JP3099907B2 - Semiconductor processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor processing apparatus, and more particularly to a semiconductor processing apparatus for processing a semiconductor wafer with a plurality of processing liquids.

[0002]

2. Description of the Related Art FIG. 3 is a schematic view of a conventional semiconductor processing apparatus. As shown in FIG. 3, a processing bath 101 contains a processing liquid 107 for processing a semiconductor wafer. The processing liquid overflowing from the processing tank 101 is recovered by the recovery unit 102, dust and the like are removed by the circulation pump 103 through the filter 104, and then returned to the processing tank 101 from the processing liquid supply port 105 again. On the other hand, the processing liquid 107 in the processing tank 101 is discharged from the drain port 106. And
Pure water 113 for washing semiconductor wafers with water is used in washing tank 1
10 are accommodated. Pure water supply port 1 is provided in washing tank 110
Pure water is supplied from 12, and overflowing pure water 113 is discharged from a drain port 111.

The operation of the above-described configuration will now be described.

[0004] A semiconductor wafer (not shown) as a chemical processing object is immersed in a processing liquid 107 in a processing bath 101 for a predetermined time and undergoes a chemical processing in a predetermined semiconductor process. The processing liquid 107 in the processing tank 101 is circulated from the recovery unit 102 to the processing tank 101 via the circulation pump 103, the filter 104, and the processing liquid supply port 105. By this circulation, the processing liquid is dust-removed and is always kept in a clean state. The semiconductor wafer that has been processed in the processing tank 101 is lifted out of the processing tank 101, and
01 is moved.

[0005] Wafers are put in pure water 11 in this washing tank 110.
3 is an overflow cleaning process.

In order to replace the processing liquid 107 in the processing tank 101 with another processing liquid, the circulation pump 103 is temporarily stopped,
The processing liquid 107 is drained, and a new processing liquid is injected into the tank 101. Thereafter, the circulation pump 103 is operated again to circulate the processing liquid.

[0007]

As described above, the conventional semiconductor processing apparatus is configured such that the semiconductor wafer is moved between the two tanks of the processing tank 101 and the washing tank 110 to perform the processing and the washing. It had been. For this reason, the processing tank 10
While moving the semiconductor wafer from 1 to the washing tank 110,
The wafer may be contaminated with dust in the atmosphere, or the processing liquid may drop during the movement, causing unevenness in the processing liquid. For example, when the processing solution is an etching solution, etching unevenness is formed on the wafer surface.

Further, when the processing liquid in the processing tank 101 is changed, the repetition of stopping and restarting the circulating pump 103 changes the pressure applied to the filter 104. Along with this, the captured dust is re-supplied to the processing tank 101, resulting in a significant decrease in the particle capturing function.

[0009] The present invention has been made in view of the above,
An object of the present invention is to provide a semiconductor processing apparatus in which a pump is continuously operated and a semiconductor wafer is not exposed to air during processing.

[0010]

The first device of the present invention comprises:
A first circulating system that circulates a first processing liquid for processing the wafer between a processing tank that stores semiconductor wafers, a pump, and a filtration filter; A second circulating system that bypasses and circulates the processing tank between the filter and the filtration filter, and stops the circulation of the first processing liquid in the first circulating system; And a first processing liquid replacement unit that discharges the first processing liquid in the processing tank to the outside and allows the second processing liquid to flow into the processing tank in this state. ,
The second processing liquid in the processing tank is discharged to the outside, the first processing liquid in the second circulating system flows into the processing tank, and the first circulating system returns to the first circulating system. And a second processing liquid replacement means for circulating the first processing liquid.

[0011] In a second apparatus of the present invention, the ratio of the amount of the first processing liquid flowing through the first circulation system to the amount of the first processing liquid flowing through the second circulation system is arbitrary. The apparatus further includes a flow rate comparing and adjusting means which can be adjusted to a predetermined value.

[0012] The third device of the present invention is the above-mentioned first or second device.
In the apparatus described above, the first or second second circulation system is configured to include a spare tank that stores the first processing liquid.

[0013]

The semiconductor wafer is processed in the processing tank while the first processing liquid is circulating in the first circulation system. After the treatment with the first treatment liquid is completed, the first treatment liquid is circulated in the second circulation system so as not to flow in the second circulation system. In this state, the first processing liquid in the processing tank is replaced with the second processing liquid. When the processing of the wafer with the second processing liquid is completed, the second processing liquid is discharged from the processing tank. After this,
The first processing liquid circulating in the second circulation system is again recycled to the first processing liquid.
Inject and circulate in the circulatory system.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a semiconductor processing apparatus according to one embodiment of the present invention. As shown in FIG. 1, a processing solution 101 is provided in a processing bath 101 for processing a semiconductor wafer.
07 are accommodated. The processing tank 101 includes a collection unit 10.
2 and a drain port 106 on the bottom of the processing tank 101.
Having. Both drain outlets 203 and 106 are in the preliminary tank 2
06 and connected to a drain line 204. The processing liquid in the preliminary tank 206 reaches the flow control valve 209 from the circulation pump 103 through the filtration filter 104. By the action of the flow control valve 209, a part of the processing liquid is returned to the processing tank 101 through the processing tank supply line 213, and the remaining part is circulated to the preliminary tank 206 through the preliminary tank supply line 212. The flow control valve 209 allocates the liquid from the filter 104 to the processing tank supply line 213 and the preliminary tank supply line 212 at an arbitrary ratio. Of course, it is also possible to switch the flow to only one of them. In a normal case, the water is circulated in approximately half halves. In addition, the processing tank 101 is provided with a pure water supply line 210 and a new liquid supply line 215 in addition to the processing tank supply line 213, so that pure water for cleaning processing and new liquid for another processing can be freely used. It is possible to supply.

The operation of the above-described configuration will be described by taking as an example a case where a semiconductor wafer is subjected to a chemical treatment with an aqueous solution of hydrofluoric acid (HF) and then subjected to a cleaning treatment with pure water.

HF is used as the processing liquid 107 in the processing tank 101.
Is satisfied. A semiconductor wafer set on a carrier (not shown) is immersed in the liquid 107 for a predetermined time, and has undergone a predetermined chemical treatment. In this case, the processing liquid (HF) overflowing from the processing tank 101 falls from the recovery unit 102 to the preliminary tank 206 through the drain port 203 and the preliminary tank supply line 205. The processing liquid (HF) in the preliminary tank 206 undergoes filter processing such as particle removal from the circulation pump 103 via the filter 104, and a part of the processing liquid (HF) flows through the processing tank supply line 213 through the flow rate control valve 209.
Circulates. The rest of the processing liquid divided by the flow control valve 209 is circulated to the preliminary tank 206 through the preliminary tank supply line 212.

When the treatment with the treatment liquid (HF) is completed,
The supply of the processing liquid to the processing tank 101 is stopped by the flow control valve 209, and all the processing liquid circulates from the preliminary tank supply line 212 to the preliminary tank 206. As a result, the processing liquid in the preliminary tank 206 is circulated to the circulation pump 103, the filter 104, the flow control valve 209, the preliminary tank supply line 212, and the preliminary tank 206.

Next, the drain port 106 of the processing tank 101 is opened, and the processing liquid 107 is entirely dropped into the preliminary tank 206. Incidentally, when the processing liquid 107 is not used thereafter, the drainage liquid is discharged from the drain line 204. After draining the processing liquid 107 from the processing tank 101, pure water is supplied from the pure water supply port 210 to wash the semiconductor wafer, and the processing is terminated.

Thereafter, the semiconductor wafer is pulled up, and the processing liquid (pure water) in the processing tank 101 through the drain line 204.
Drain 107. Furthermore, the flow control valve 2
The HF circulated through the preliminary tank 206 through 09 is led out to the processing tank supply line 213, so that the processing liquid 107 in the processing tank 101 is converted into HF again to prepare for new processing.

As a result of the above-mentioned operations, the problem of vibration applied to the wafer and the hydrophobicity of the wafer surface, which have conventionally been caused when the semiconductor wafer is moved between the tanks between the chemical treatment and the cleaning treatment, are caused. This solves the problem that the wafer surface is activated and dust tends to adhere. Further, since the semiconductor wafer is not moved between the tanks, a clean wafer surface can be kept. In addition, the pump does not need to be stopped or restarted when the processing liquid is exchanged, so that there is no pressure fluctuation on the filter for removing particles in the processing liquid, and the cleanliness of the processing liquid can be improved.

FIG. 2 shows a modification of the processing tank 101 of FIG. That is, FIG. 2 shows a part of the single-wafer processing apparatus. As shown in FIG. 2, the wafer 304 is immersed in the processing liquid 107 in the processing tank 101, and the processing liquid is supplied from the supply port 303 and discharged from the drain port 106. The supply system and the drainage system are the same as in FIG.

[0023]

As described above, according to the semiconductor processing apparatus of the present invention, the processing liquid in the processing tank can be switched without stopping the pump, so that the dust removing capability can be maintained. In addition, since there is no need to move the semiconductor wafer between the chemical solution treatment and the cleaning process, it is possible to prevent dust from adhering to the semiconductor wafer and the dripping of the semiconductor wafer due to the movement, thereby improving quality and process reliability. Further, since the chemical solution treatment and the cleaning treatment can be performed in one treatment tank, the size of the apparatus can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a semiconductor processing apparatus according to one embodiment of the present invention.

FIG. 2 is a partial schematic configuration diagram showing another example of the processing tank having the configuration shown in FIG.

FIG. 3 is a schematic configuration diagram of a conventional semiconductor processing apparatus.

[Explanation of symbols]

 Reference Signs List 101 processing tank 102 recovery unit 103 circulation pump 104 filter 105 processing liquid supply port 106 drain port 107 processing liquid 110 rinsing tank 111 drain port 112 pure water supply port 113 pure water 203 drain port 204 drain line 205 reserve tank supply line 206 reserve tank 209 Flow control valve 210 Pure water supply port 212 Preliminary tank supply line 213 Processing tank supply line 215 New solution supply line 303 Supply port 304 Wafer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/304 H01L 21/306 B08B 3/04

Claims (3)

(57) [Claims] 1. A first circulating system for circulating a first processing solution for processing a wafer between a processing tank for storing a semiconductor wafer, a pump, and a filter, and the first processing solution. Between the pump and the filtration filter, bypassing the processing tank, circulating a second circulation system, stopping the circulation of the first processing solution in the first circulation system, Only the circulation in the second circulation system is continued, and in this state, the first processing liquid in the processing tank is discharged to the outside,
A first processing liquid replacement unit that causes a second processing liquid to flow into the processing tank, and discharges the second processing liquid in the processing tank to the outside, and removes the second processing liquid in the second circulation system. A second processing liquid replacement means for causing the first processing liquid to flow into the processing tank and circulating the first processing liquid again in the first circulation system. apparatus. 2. The apparatus according to claim 1, further comprising a flow rate comparing and adjusting means capable of arbitrarily adjusting a ratio of an amount of said first processing liquid flowing through said first circulating system to an amount of flowing said second circulating system. Item 1
The described device. 3. The apparatus according to claim 1, wherein the second circulation system includes a spare tank for storing the first processing liquid.