JPH0714812A - Wet processor for wafer - Google Patents

Abstract

PURPOSE:To obtain a wet processor capable of coping with a large diameter wafer in less particles at low chemical solution cost by a method wherein the processor is provided with a chemical solution producer part using one of gas sources as an ozonizer while making the chemical solution from a solution mixed with respective gasses. CONSTITUTION:A chemical solution producer part 50 is provided with gas cylinders 51a, 51b as gas sources and an ozonizer 52. Fluoric anhydride fed from the gas cylinder 51a is dissolved in pure water in a mixer 53a and the solution is fed to a nozzle in a processing unit 20. Ammonia gas fed, from the gas cylinder 51b and the ozon gas fed from the ozonizer 52 are dissolved in pure water in another mixer 53b and the solution is fed to the nozzle in the processing unit 20. Finally, ozone gas fed from the ozonizer 52 is dissolved in hydrochloric acid in a mixer 53c and the solution is fed to one nozzle in another processing unit 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer wet processing apparatus used for cleaning semiconductor wafers.

[0002]

2. Description of the Related Art A manufactured semiconductor wafer is subjected to a precise cleaning process. This cleaning process is usually performed in a batch system. That is, a plurality of wafers are housed in a carrier and sequentially transferred to a plurality of processing tanks. Various chemicals and pure water are supplied to the plurality of processing tanks. As the chemical solution, sulfuric acid hydrogen peroxide solution and ammonia hydrogen peroxide solution are widely used. These chemicals are supplied to the processing apparatus in a state of a completed liquid after preparation.

[0003]

In such a batch type processing apparatus, when the outer diameter of the wafer is larger than 10 to 12 inches, it becomes difficult to handle the wafer and the processing becomes difficult. Further, since the chemical liquid is supplied in the state of the completed liquid after the preparation, particles tend to increase and the yield tends to deteriorate. Further, since a large amount of hydrogen peroxide is required, there is a problem that the cost of the chemical solution increases.

The object of the present invention is to deal with large diameter wafers,
Moreover, it is an object of the present invention to provide a wafer wet processing apparatus having a small number of particles and a low chemical solution cost.

[0005]

A wafer wet processing apparatus of the present invention comprises a single wafer processing unit for spraying a processing liquid onto a wafer at each stage, and various chemicals used in the single wafer processing unit. Is provided with a plurality of gas sources, each gas is mixed with a liquid to form a chemical liquid, and one of the plurality of gas sources is an ozonizer.

[0006]

The single wafer type wafer processing unit also processes large-diameter wafers. Since the chemical liquid is generated as much as possible by using various high-purity gases in the processing apparatus, particles are reduced. Since ozone is used instead of hydrogen peroxide, chemical solution cost is saved.

[0007]

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

FIG. 1 is a schematic view showing the overall structure of an example of a wafer wet processing apparatus embodying the present invention, FIG. 2 is a schematic view showing an example of the structure of a single wafer processing unit, and FIG. It is a schematic diagram which shows a structural example.

This processing apparatus is a wafer cleaning apparatus,
A loader 10 for storing unprocessed wafers, two single wafer processing units 20, 30; an unloader 40 for storing processed wafers; and processing units 20, 30.
Processing unit 20, 30 for generating various chemicals used in
And a chemical liquid generation unit 50 for supplying the

The processing unit 20 includes annular stages 21a, 21b, 21c and 21 provided in four stages from top to bottom.
have d. The first stage 21a is for ammonia cleaning, the second stage 21b is for pure water cleaning, the third stage 21c is for hydrofluoric acid cleaning, and the fourth stage 21d is for cleaning.
Is for cleaning with pure water. A chuck 22 that holds one wafer W horizontally is provided inside the stage group. The chuck 22 is driven up and down by a drive source 23 to transfer the wafer W to each stage in sequence, and is rotationally driven at each stage to rotate the wafer W in the circumferential direction.

Above the chuck 22, three types of nozzles 2 are provided.
4a, 24b and 24c are provided downward. The nozzle 24a is for ammonia water used for ammonia cleaning in the first stage, the nozzle 24b is for hydrofluoric acid water used for hydrofluoric acid cleaning in the third stage, and the nozzle 24c is 2
It is for pure water used for cleaning pure water in the fourth stage and the fourth stage.

The processing unit 30 is also the processing unit 20.
It is basically the same configuration as, but there are three stages,
There are two nozzles. The first stage is for cleaning hydrochloric acid,
The second stage is for pure water cleaning, and the third stage is for spin drying. One of the two nozzles is for hydrochloric acid and is used for cleaning hydrochloric acid in the first stage.
The other is for pure water and is used for pure water cleaning in the second stage.

The chemical liquid generator 50 has gas cylinders 51a and 51b and an ozonizer 52 as gas sources. Further, it has three mixers 53a, 53b, 53c.
The gas cylinder 51a is filled with anhydrous hydrofluoric acid gas, and the gas cylinder 51b is filled with ammonia gas.

The mixer 53a dissolves and mixes the anhydrous hydrofluoric acid supplied from the gas cylinder 51a in pure water and supplies it to the nozzle 24b in the processing unit 20. The mixer 53b dissolves and mixes the ammonia gas supplied from the gas cylinder 51b and the ozone gas supplied from the ozonizer 52 in pure water, and supplies it to the nozzle 24a in the processing unit 20. The mixer 53c dissolves and mixes ozone gas supplied from the ozonizer 52 in hydrochloric acid, and supplies the ozone gas to one nozzle of the processing unit 30. In addition, pure water is treated without going through the mixer.
0 to the nozzle 24a and the other nozzle in the processing unit 30.

In this processing apparatus, the wafer W is cleaned in the following order.

The wafer W in the loader 10 is loaded into the processing unit 20 and is sequentially transferred by the chuck 22 from the first stage 21a to the fourth stage 21d.

On the first stage 21a, while rotating the wafer W, organic substances on the surface are removed by ammonia water containing ozone ejected from the nozzle 24a. On the second stage 21b, while rotating the wafer W, the ammonia water on the surface is washed with pure water ejected from the nozzle 24c. On the third stage 21c, while the wafer W is rotating, the surface oxide film is removed by hydrofluoric acid cleaning water containing ozone ejected from the nozzle 24b. Four
On the second stage 21d, the hydrofluoric acid water on the surface is removed by the pure water jetted from the nozzle 24c while the wafer W rotates.

The wafer W that has undergone the pure water cleaning process on the fourth stage 21d is transferred into the processing unit 30 and is sequentially transferred from the first stage to the third stage.

In the first stage, while the wafer W is rotating, the heavy metal on the surface is removed by hydrochloric acid containing ozone ejected from one nozzle. On the second stage, while the wafer W is rotating, the surface hydrochloric acid is removed by the pure water ejected from the other nozzle. At the third stage, the water content on the surface of the wafer W is removed by spin drying by rotation.

The wafer W which has been dried is unloaded by the unloader 40.
Housed in. While the processing unit 30 is performing the processing, the processing unit 20 also performs the processing.

As described above, since the present processing apparatus uses the single wafer processing units 20 and 30 for processing the wafers one by one, it is possible to process large-diameter wafers. Since the chemical liquid generation unit 50 is provided and the chemical liquid is generated by using various gases as much as possible in the processing apparatus, and the use of the completed liquid is refrained, particles can be reduced. Since ozone is used instead of hydrogen peroxide, chemical solution cost can be saved.

Although two single wafer processing units are used in the above embodiment, the number of single wafer processing units is not limited.

The configuration of the processing unit is not limited to the above embodiment, and the number of stages can be appropriately determined according to the processing process.

The treatment process is not limited to the above embodiment, and various treatments can be performed using various chemicals.

[0025]

As described above, the wafer wet processing apparatus of the present invention is compatible with large-diameter wafers by including the single wafer type wafer processing unit and the chemical liquid generating section having a plurality of gas sources containing ozone. Moreover, the number of particles is small, and the chemical solution cost can be saved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an overall configuration of an example of a wafer wet processing apparatus embodying the present invention.

FIG. 2 is a schematic diagram showing a configuration example of a single wafer processing unit.

FIG. 3 is a schematic diagram illustrating a configuration example of a chemical liquid generation unit.

[Explanation of symbols]

 W Wafer 20,30 Processing unit 21a to 21d Stage 22 Chuck 24a to 24c Nozzle 50 Chemical liquid generation part 51a, 51b Gas cylinder 52 Ozonizer 53a to 53c Mixer

Claims (1)

[Claims] 1. A single-wafer processing unit for spraying a processing liquid onto a wafer at each stage, and a plurality of gas sources for generating various chemicals used in the single-wafer processing unit, A wet processing apparatus for wafers, characterized in that each gas is mixed with a liquid to form a chemical liquid, and a chemical liquid generation unit in which one of a plurality of gas sources is an ozonizer.