JPH11260780A - Spin cleaning apparatus and spin cleaning method - Google Patents

Abstract

(57) [Problem] To provide a spin cleaning apparatus and a spin cleaning method capable of preventing contamination of a substrate without splashing of a cleaning liquid onto an inner wall of a cleaning tank. To provide a spin cleaning device and a spin cleaning method in which gas can be easily introduced. To provide a spin cleaning apparatus and a spin cleaning method capable of constantly wetting the center of a substrate. SOLUTION: In a spin cleaning apparatus having a means 11 for rotatably holding a substrate 1 in a cleaning tank 8 and a nozzle 4 for supplying a cleaning liquid, wherein a lid 2 is provided above the substrate 1.
A nozzle 4 is provided on the cover 2 so as to be swingable with respect to the substrate 1 and a nozzle 4 for supplying a cleaning liquid to the cover 2, and the tip of the nozzle 4 protrudes from the lower surface of the cover 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus for cleaning a substrate (silicon wafer or glass) for producing a device in a process for producing a semiconductor device or a liquid crystal display device.

[0002]

BACKGROUND OF THE INVENTION Semiconductor devices formed on semiconductor substrates are becoming denser and smaller to submicron levels. In order to achieve high densification, the surface of the substrate must be kept ultra-clean. That is, organic substances, metals, various particles, and oxides (oxide films) must be removed from the entire substrate. Therefore, substrate cleaning is performed.

[0003] With the increase in the diameter of the substrate, a batch-type cleaning apparatus that immerses a plurality of substrates in a cleaning tank storing a cleaning liquid to perform cleaning from a conventional mainstream substrate to a holder that can rotate one substrate. The conversion to a single-wafer spin cleaning apparatus in which a substrate is rotated by mounting and a cleaning liquid is dropped from above is attempted.

[0004] The former occupies a large area for processing a plurality of sheets, and the apparatus is further increased in size as the diameter of the substrate increases. A large amount of pure water is used for rinsing. The latter has a small device area and can greatly reduce the amount of pure water used. The latter is desirable in view of the layout of the clean room and the burden on utilities.

[0005]

SUMMARY OF THE INVENTION In a spin cleaning apparatus, the cleaning liquid blown out of the substrate by spinning includes:
Some objects hit the inner wall of the washing tank and bounce off. This causes contamination of the substrate. In order to avoid this, it is effective to increase the distance from the inner wall of the chamber, but this increases the device area. One of the means for this is to provide a lid above the substrate, but it becomes difficult to supply a cleaning liquid and introduce a gas.

When a lid is provided, a droplet may adhere to the lower surface of the lid and drop on the substrate.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a spin cleaning apparatus and a spin cleaning method capable of preventing the cleaning liquid from splashing onto the inner wall of the cleaning tank and preventing contamination of the substrate.

An object of the present invention is to provide a spin cleaning apparatus and a spin cleaning method that can easily introduce a gas.

[0009]

According to the present invention, there is provided a spin cleaning apparatus comprising a means for rotatably holding a substrate in a cleaning tank, a nozzle for supplying a cleaning liquid, and a lid provided above the substrate. In the cleaning apparatus, a nozzle is provided on the lid so as to be swingable with respect to the substrate, and a nozzle for supplying a cleaning liquid to the lid is provided, and a tip of the nozzle protrudes from a lower surface of the lid.

The spin cleaning method of the present invention uses a spin cleaning apparatus having a means for rotatably holding a substrate in a cleaning tank, a nozzle for supplying a cleaning liquid, and a lid provided above the substrate. In a spin cleaning method for performing cleaning by rotating a substrate and supplying the cleaning liquid to the surface of the substrate, the lid is swung while the cleaning liquid is supplied from a nozzle. Preferably, the lid is provided with a heater.

In the present spin cleaning apparatus, it is preferable that the lid is provided with a gas inlet for ejecting gas to the substrate surface.

Further, it is preferable that the size of the cover does not protrude from the substrate when the cover is swung.

Further, it is preferable to heat the lid with a heater during the cleaning.

It is preferable that a gas is ejected from the gas inlet provided on the lid to the substrate surface.

When the lid is swung, it is preferable to perform cleaning without the lid protruding from the substrate.

[0016]

FIG. 1 shows a spin cleaning apparatus according to an embodiment.

A means 11 for rotatably holding the substrate 1 in the cleaning tank 8 and a nozzle 4 for supplying a cleaning liquid are provided. A lid 2 is provided above the substrate 1 so that it can swing with respect to the substrate 1. A nozzle 4 is provided on the lid 2 and supplies the cleaning liquid to the lid 2, and the tip of the nozzle 4 protrudes from the lower surface of the lid 2.

In this embodiment, the means for holding the substrate 1 includes a rotating shaft 12 and a susceptor 13 attached to the rotating shaft.

The lid 2 is connected to a rotating shaft 10 via a bar 6.
, And the lid 2 swings with the rotation of the rotating shaft 10.

Reference numeral 14 denotes a gas supply line.

The lid 2 is arranged so as not to protrude from the substrate 1 even when it swings.

Further, a heater 3 is provided above the lid 2.

Next, a cleaning method will be described.

First, a square glass substrate, a quartz substrate, a circular silicon wafer, or the like is fixed on a substrate holder in a cleaning tank.

The substrate is rotated.

The cleaning liquid is supplied from a nozzle provided on the lid. The entire lid is scanned, and the cleaning liquid from the nozzle is directly irradiated on the entire substrate. At that time, the substrate does not protrude from the lid.

During the drying step, clean dry nitrogen is blown from the gas inlet.

The washing liquid used in the present invention is selected from pure water, ultrapure water, ozone-added ultrapure water, hydrofluoric acid, aqueous hydrogen peroxide, ammonium hydroxide, sulfuric acid, hydrochloric acid, isopropyl alcohol and the like. At least one or at least two mixed liquids selected from these are exemplified.

Further, the washing steps with some washing liquids may be performed in time series. Further, it is also preferable to apply megasonic vibration. More preferably, ozone-added pure water, hydrofluoric acid, a hydrogen peroxide solution, a surfactant, a pure water is prepared, a washing step with ozone-added pure water, including hydrofluoric acid, a hydrogen peroxide solution, and a surfactant It is preferable that the washing step with pure water, the washing step with ozone-added pure water, the washing step with diluted hydrofluoric acid, and the washing step with pure water can be sequentially performed.

This cleaning method is effective even at room temperature, and does not need to be heated to about 100 degrees unlike the conventional RCA cleaning.

[0031]

EXAMPLE This example is a result of cleaning an 8-inch silicon wafer by using a spin cleaning apparatus.

The cleaning was performed by a spin cleaning method.

The entire substrate was contaminated with alumina particles. The silicon substrate was cleaned with ultrapure water containing 0.5 wt%, H ₂ O ₂ and 50 ppm of a surfactant while applying vibration at a frequency of 1.5 MHz. At that time, rinsing with ultrapure water was performed.

The conventional example has no lid, and the embodiment has a lid above the substrate.

The rotation speed at this time is 500, 1000, 3
000 rpm.

Table 1 shows the results of counting the number of substrate particles after cleaning with a surface foreign matter inspection device and calculating the fine particle removal rate. The evaluation fine particle diameter is 0.20 μm or more. Cleaning time is 30
Seconds.

[0037]

[Table 1] In the conventional example, as a result of cleaning at a rotation speed of 1000 or 3000 rpm, recontamination due to rebound from the inner wall of the chamber is observed. In the embodiment, recontamination due to bounce is prevented, and the cleaning is completed.

During washing and drying, droplets sometimes fall from the lower surface of the lid.

By heating the lid with the heater provided on the lid, the drop of the liquid droplet from the lower surface of the lid was reliably eliminated.

When no gas is introduced during drying, 1000
At 15 rpm and 15 seconds, it was visually confirmed that a droplet remained at the center of the substrate. It was confirmed that no droplets remained under the same conditions by introducing dry nitrogen.

[0041]

The effects of the present invention are as follows.

By providing the lid on the substrate, it is possible to prevent the cleaning liquid splashed by the spin from rebounding from the inner wall of the chamber to the substrate.

Even if the cleaning liquid adheres to the upper part of the lid, the cleaning liquid does not drop by heating with the heater plate.

Drying is performed by blowing clean dry nitrogen through a gas inlet provided in the lid during the drying process.

Since the nozzle swings with the swing of the lid, the center of the substrate does not dry, and there is no need to newly provide a cleaning liquid supply system and a system for holding the same.

Since the center of the substrate does not dry, there is no need to provide a complicated movable system.

[Brief description of the drawings]

FIG. 1 is a top view (a) and a side view (b) of a spin cleaning machine for a substrate.

[Explanation of symbols]

 1 substrate to be cleaned, 2 lids, 3 heaters, 4 nozzles, 5 gas inlets, 6 bars, 8 cleaning tanks, 10 rotation shafts, 11 holding means, 12 rotation shafts, 13 susceptors, 14 gas supply lines.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yuhisa Nitta 4-1-1 Hongo, Bunkyo-ku, Tokyo Ultra Clean Technology Development Laboratory Co., Ltd. (72) Inventor Mitsunori Nakamori Aramaki Aoba-ku, Aoba-ku, Sendai, Miyagi Prefecture Aoba (unnumbered) Tohoku University

Claims (8)

[Claims] In a spin cleaning apparatus having a means for rotatably holding a substrate in a cleaning tank and a nozzle for supplying a cleaning liquid, and a lid provided above the substrate, the spin cleaning apparatus can swing with respect to the substrate. A spin cleaning device comprising: a nozzle provided on a lid; and a nozzle for supplying a cleaning liquid to the lid, wherein a tip of the nozzle projects from a lower surface of the lid. 2. The spin cleaning apparatus according to claim 1, wherein the lid is provided with a heater. 3. The apparatus according to claim 1, wherein the cover is provided with a gas inlet for ejecting gas to the surface of the substrate.
Or the spin cleaning device according to 2. 4. The spin cleaning apparatus according to claim 1, wherein the lid has a size that does not protrude from the substrate when the lid is swung. 5. A spin cleaning apparatus having a means for rotatably holding a substrate in a cleaning tank and a nozzle for supplying a cleaning liquid, and a spin cleaning apparatus provided with a lid above the substrate to rotate the substrate. A spin cleaning method for supplying a cleaning liquid to a surface of a substrate for cleaning, wherein the lid is swung while the cleaning liquid is supplied from a nozzle. 6. The spin cleaning method according to claim 5, wherein the lid is heated by a heater during the cleaning. 7. The spin cleaning apparatus according to claim 5, wherein a gas is jetted from a gas inlet provided in the lid to a surface of the substrate. 8. The spin cleaning apparatus according to claim 5, wherein when the lid is swung, the cleaning is performed without the lid protruding from the substrate.