JPH06232108A - Removal of foreign matter - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a technique capable of easily removing foreign matter attached to the back surface of a semiconductor wafer. [Structure] Adhesive tape 2 is brought into contact with the back surface of wafer 1 held horizontally, and then peeled off to remove minute foreign matter 6 attached to the back surface of wafer 1. To bring the adhesive tape 2 into contact with the back surface of the wafer 1, the roller 5 is horizontally moved from one end of the wafer 1 to the other end while rotating at a predetermined speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foreign matter removing technique,
For example, the present invention relates to a technique that is effective when applied to the removal of foreign matter attached to the back surface of a semiconductor wafer.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor integrated circuit device (wafer process), when a semiconductor wafer is transferred to a manufacturing device, a solid is brought into contact with the back surface of the wafer everywhere. Regardless of the type, a large amount of foreign matter adheres, which causes a decrease in manufacturing yield.

That is, the foreign matter attached to the back surface of the wafer is reattached to the front surface of the wafer through the gas or liquid which comes into contact with the wafer, which causes disconnection failure or short circuit failure of the integrated circuit.

Further, in the exposure step of transferring the integrated circuit pattern formed on the photomask onto the photoresist on the wafer, when the wafer is placed on the stage of the exposure apparatus, it is possible that foreign matter adheres to the back surface of the wafer. Since the flatness is impaired, the position of the photoresist deviates from the depth of focus of exposure, resulting in poor resolution.

Therefore, conventionally, among the foreign matters attached to the back surface of the wafer, the organic foreign matters are removed by cleaning the wafer with a chemical solution such as sulfuric acid, nitric acid, or an organic solvent, while the inorganic foreign matters are removed. The wafer is removed by cleaning it with a chemical solution such as acid or alkali.

[0006]

However, the conventional method of cleaning a wafer with a chemical solution such as acid or alkali requires a rinse step and a drying step with pure water after the chemical solution cleaning, which complicates the steps. However, there is a problem that various equipments such as a cleaning device, a drying device, and a chemical treatment device are required.
In addition, the cleaning of the wafer with the chemical solution may adversely affect the integrated circuit formed on the surface of the wafer.

Therefore, an object of the present invention is to provide a technique capable of easily removing foreign matter attached to the back surface of a wafer or the like.

The above and other objects and novel features of the present invention will be apparent from the description of the specification and the accompanying drawings.

[0009]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

In the present invention, an adhesive substance such as an adhesive tape is brought into contact with the back surface of the wafer, and then the adhesive material is peeled off to remove minute foreign matters adhering to the back surface of the wafer.

[0011]

According to the above-mentioned means, by peeling off the adhesive substance brought into contact with the back surface of the wafer, the minute foreign matter adhering to the back surface of the wafer is transferred to the adhesive substance, and the back surface of the wafer is cleaned. It

[0012]

[Embodiment 1] A foreign matter removing method according to an embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In this embodiment, the adhesive tape 2 is brought into contact with the back surface of the wafer 1 while the wafer 1 is held horizontally. Wafer 1
To keep the horizontal, as an example, as shown in Figure 1,
One end of each of the plurality of suction pins 3 is brought into contact with the peripheral portion of the surface of the wafer 1 to suck the wafer 1 by negative pressure. Alternatively,
As shown in FIG. 2, the groove 4 into which the peripheral portion of the wafer 1 is inserted
The wafer 1 may be held by using a plurality of jigs 4 provided with a.

The adhesive tape 2 is a tape base material 2 such as a woven cloth.
The adhesive 2b is applied to one surface of a, and the width thereof is equal to or slightly larger than the diameter of the wafer 1. To bring this adhesive tape 2 into contact with the back surface of the wafer 1, a roller 5 is used as an example. Then, the roller 5 is rotated at a predetermined speed and horizontally moved from one end of the wafer 1 to the other end.

As a result, the adhesive tape 2 comes into line contact with the back surface of the wafer 1 and is then quickly peeled off, so that the minute foreign matter 6 adhering to the back surface of the wafer 1 adheres to the adhesive tape 2 and the wafer 1 The back side of is cleaned.

Instead of moving the roller 5 horizontally, the wafer 1 may be moved horizontally, or the roller 5 and the wafer 1 may be moved horizontally in opposite directions.

[0017]

[Embodiment 2] In the above-mentioned embodiment, the adhesive tape 2 was brought into contact with the back surface of the wafer 1 by using the roller 5, but in this embodiment, as shown in FIG. Stick the adhesive tape 2 on the entire back surface of 1.

In order to hold the wafer 1 horizontally, as an example, an adhesive tape 7 is attached to the peripheral portion of the surface of the wafer 1,
One end of the suction pin 3 is brought into contact therewith and the wafer 1 is sucked by negative pressure. The adhesive tape 7 has a stronger adhesive force than the adhesive tape 2 attached to the back surface of the wafer 1.

Next, as shown in FIG. 3B, one end of the adhesive tape 2 is held by using a jig 8 such as tweezers, and the adhesive tape 2 is peeled from the back surface of the wafer 1. As a result, the minute foreign matter 6 attached to the back surface of the wafer 1 is attached to the adhesive tape 2, and the back surface of the wafer 1 is cleaned.

The invention made by the present inventor has been specifically described above based on the embodiments, but the present invention is not limited to the embodiments and can be variously modified without departing from the scope of the invention. Needless to say.

In the above-mentioned embodiment, the adhesive tape is attached to the back surface of the wafer, but the present invention is not limited to this. For example, a roller coated with an adhesive is pressed against the back surface of the wafer so that one end It is also possible to remove the foreign matter by rotating it to.

Further, the present invention can be applied not only to the case where the back surface of the wafer is removed, but also to the case where foreign matter attached to the surface is removed.

In the above description, the case where the invention made by the present inventor is mainly applied to the removal of foreign matter from the wafer has been described. However, the present invention is not limited to this. For example, a substrate or a printed wiring of a liquid crystal display device It can also be applied to remove foreign substances such as substrates.

[0024]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

According to the present invention, by bringing an adhesive substance such as an adhesive tape into contact with the back surface of the wafer and then peeling it off, it becomes possible to easily remove minute foreign matters attached to the back surface of the wafer. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a wafer showing a foreign matter removing method according to an embodiment of the present invention.

FIG. 2 is a sectional view of a wafer showing a foreign matter removing method according to another embodiment of the present invention.

3 (a) and 3 (b) are cross-sectional views of a wafer, respectively, showing a foreign matter removing method according to another embodiment of the present invention.

[Explanation of symbols]

 1 Wafer 2 Adhesive Tape 2a Tape Base Material 2b Adhesive 3 Adsorption Pin 4 Jig 4a Groove 5 Roller 6 Foreign Material 7 Adhesive Tape 8 Jig

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichiro Shirai 2326 Imai, Ome City, Tokyo Hitachi, Ltd. Device Development Center (72) Inventor Toshihiko Onozuka 2326 Imai, Ome City, Tokyo Hitachi Device Development Center Within

Claims (2)

[Claims] 1. A foreign matter removing method, characterized in that a minute foreign matter attached to one surface of the substrate is removed by bringing an adhesive substance into contact with one surface of the substrate and then peeling the adhesive substance. 2. The foreign matter removing method according to claim 1, wherein the adhesive substance is an adhesive tape.