KR20240103325A - Apparatus for Inspecting Wafer Edges - Google Patents

Abstract

The embodiment relates to a wafer edge inspection device that can measure edge defects of wafers stored in a cassette after cleaning and drying the wafers.
According to one aspect of the embodiment, a cassette in which a plurality of wafers are stored in a row while standing at predetermined intervals in the front-back direction; a chamber in which the cassette is accommodated; a roller that supports lower ends of the wafers stored in the cassette inside the chamber and rotates the wafers; an air nozzle movably disposed inside the chamber and spraying air toward the wafers stored in the cassette; and a vision sensor movably disposed inside the chamber and measuring edge defects of wafers stored in the cassette.

Description

Wafer Edge Inspection Apparatus {Apparatus for Inspecting Wafer Edges}

The embodiment relates to a wafer edge inspection device that can measure edge defects of wafers stored in a cassette after cleaning and drying the wafers.

Generally, wafers are produced as wafers for semiconductor device manufacturing through a series of processes such as slicing process, grinding process, lapping process, etching process, and polishing process.

During the wafer manufacturing process, the surface of the wafer may be contaminated by fine particles, metal contaminants, organic contaminants, etc. These contaminants not only deteriorate the quality of the wafer, but also cause physical defects and deterioration of the characteristics of the semiconductor device, ultimately reducing the production yield of the semiconductor device. Therefore, in order to remove contaminants on the wafer surface, a wet cleaning process is performed using an etching solution such as acid or alkali or deionized water.

The wet cleaning process is divided into a single wafer method, which cleans wafers one by one, and a batch method, which cleans wafers all at once.

1 is a diagram illustrating a typical single-wafer wafer cleaning device.

As shown in FIG. 1, the single-wafer wafer cleaning device includes a chuck (1) for vacuum suction of the wafer (W), and a cleaning nozzle (2) for spraying a cleaning liquid onto the upper side of the wafer (W) adsorbed on the chuck (1). and an air nozzle 3 that sprays air onto the upper side of the wafer W mounted on the chuck 1.

When the wafer (W) is vacuum-sucked to the chuck (1) and the chuck (1) rotates at high speed, the cleaning nozzle (2) sprays the cleaning liquid onto the upper side of the wafer (W) to clean it, and then the air nozzle (3) cleans the wafer (W). Drying can be achieved by spraying high-pressure air onto the upper side of the wafer (W).

However, even if the wafer (W) is dried using a single wafer method, the center of the lower surface of the wafer (W) adsorbed on the chuck cannot be completely dried, so hunting occurs when measuring the flatness of the wafer due to the cleaning solution remaining on the wafer (W). However, there is a problem in that quality control of wafers is difficult.

Therefore, even if wafers are dried using a single wafer method, natural drying is performed separately for about 1 to 1.5 hours to completely dry the remaining cleaning solution, so a separate waiting space is required, which not only increases production time but also ensures rapid supply to subsequent processes. There is a problem that production efficiency is reduced due to difficulty.

Meanwhile, the batch wafer cleaning device can clean the surface of the wafers by immersing a plurality of wafers stored in a cassette in a cleaning tank filled with a cleaning solution for a certain period of time and generating ultrasonic waves in the cleaning solution.

However, since the wafers cleaned in the batch wafer cleaning device are loaded on the cassette, a separate drying device is required to dry the wafers loaded on the cassette all at once.

The embodiments aim to solve the above-described problems and other problems.

Another object of the embodiment is to provide a wafer edge inspection device that can measure edge defects of wafers stored in a cassette after cleaning and drying the wafers.

According to one aspect of the embodiment, a cassette in which a plurality of wafers are stored in a row while standing at predetermined intervals in the front-back direction; a chamber in which the cassette is accommodated; a roller that supports lower ends of the wafers stored in the cassette inside the chamber and rotates the wafers; an air nozzle movably disposed inside the chamber and spraying air toward the wafers stored in the cassette; and a vision sensor movably disposed inside the chamber and measuring edge defects of wafers stored in the cassette.

According to one aspect of the embodiment, the roller may be arranged long in the front-back direction on the lower side of the cassette, and may be configured in a comb shape in which slit grooves supporting lower ends of the wafers are provided at predetermined intervals.

According to one aspect of the embodiment, the air nozzle may be interlocked with the roller, and as the roller rotates, the air nozzle may be operated to spray air toward the wafers.

According to one aspect of the embodiment, a pair of air nozzles may be provided side by side on the upper side of the cassette at a predetermined interval, and may be configured to have a size at least equal to the radius of the wafer stored in the cassette.

According to one aspect of the embodiment, the vision sensor is interlocked with the roller, and as the roller rotates, the vision sensor can measure edge defects of the wafers.

According to one aspect of the embodiment, the vision sensor may be disposed above the center of the wafers stored in the cassette.

According to one aspect of the embodiment, the vision sensor may be disposed between the air nozzles.

According to one aspect of the embodiment, a transfer that simultaneously moves the air nozzle and the vision sensor in the forward and backward directions on the upper side of the cassette may be further included.

According to one aspect of the embodiment, the transfer may be composed of a cylinder that moves the air nozzle and the vision sensor in the front and rear directions of the cassette.

According to an embodiment, while the wafers stored in the cassette are rotated by rollers, each air nozzle sprays high-pressure air toward the wafers to dry them, and at the same time, a vision sensor measures edge defects of the wafers, thereby reducing the waiting time for natural drying. and space can be omitted, which has the advantage of increasing production efficiency.

In addition, since the wafers can be completely dried, the flatness of the wafer can be accurately measured and the quality of the wafer can be managed more effectively.

1 is a diagram illustrating a typical single-wafer wafer cleaning device.
Figure 2 is a front view schematically showing a wafer edge inspection device of an embodiment.
Figure 3 is a plan view schematically showing the installation structure of the air nozzle and vision sensor applied to the embodiment.

Hereinafter, this embodiment will be examined in detail with reference to the accompanying drawings.

FIG. 2 is a front view schematically showing the wafer edge inspection device of the embodiment, and FIG. 3 is a plan view schematically showing the installation structure of the air nozzle and vision sensor applied to the embodiment.

As shown in FIGS. 2 and 3, the wafer edge inspection device of the embodiment includes a cassette 110 in which wafers W are stored, a chamber 120 in which the cassette 110 is stored, and inside the chamber 120. A roller 130 for rotating the wafers W on the side of the stored cassette 110, an air nozzle 141 and 142 for spraying air onto the wafers W from inside the chamber 120, and It may include a vision sensor 150 that measures edge defects of the wafers W, and a transfer 160 that moves the air nozzles 141 and 142 and the vision sensor 150 on the upper side of the cassette 110.

The cassette 110 can store the wafers W in an upright position in a row at a predetermined interval in the front-back direction. The upper and lower surfaces of the cassette 110 may be open and configured to support both lower sides of the wafers. The wafers W may be accommodated on the upper side of the cassette 110 in an upright state, and may be rotated on the lower side of the cassette 110 by a roller 130, which will be described below.

The chamber 120 may accommodate a plurality of cassettes 110 and provide a drying space for the wafers W. Four cassettes 110 can be accommodated inside the chamber 120, and a door (not shown) through which the cassettes 110 can enter and exit may be provided on one side of the chamber.

A plurality of air nozzles 141 and 142, a vision sensor 150, and a transfer 160, which will be described below, may be provided inside the chamber 120, and a control unit (not shown) for controlling the operation of the components may be installed in the chamber ( 120) may be provided on one side. The chamber 120 may be provided with a drain port (not shown) and a drain pipe (not shown) for draining the cleaning liquid removed from the wafers W during the drying process. Of course, the inside of the chamber 120 is additionally provided with a plurality of cleaning nozzles (not shown) for spraying cleaning liquid separately from the air nozzles 141 and 142 to remove foreign substances on the surface of the wafers W before the drying process. A cleaning process may be performed, but is not limited.

Each roller 130 may be arranged long in the front-back direction on the lower side of each cassette 110 stored inside the chamber 120 and may be rotatable. The roller 130 may be configured in a comb shape with slit grooves capable of supporting lower ends of the wafers W stored in the cassette 110. Each roller 130 may be made of one of acetal, Teflon, and resin series to prevent contamination of the wafers (W) even if it directly contacts the wafers (W).

When the cassette 110 is stored in the chamber 120, the lower ends of the wafers W stored in the cassette 110 may be supported by the slit grooves of the roller 130, and the roller 130 may be rotated. Accordingly, the wafers W stored in the cassette 110 can be rotated. The operation of the roller 130 may be linked with the air nozzles 141 and 142, the vision sensor 150, and the transfer 160, which will be described below.

Each air nozzle 141 and 142 may be positioned to be movable in the forward and backward directions on the upper side of each cassette 110 stored inside the chamber 120, and may supply high-pressure air to the wafers W stored in each cassette 110. Can be sprayed towards. A high-pressure air regulator (CDA regulator (not shown)) may be provided on one side of the chamber 120 to uniformly supply high-pressure air to each air nozzle 141 and 142, and each air nozzle 141 and 142 may be connected through one pipe. It may be possible, but it is not limited.

A pair of air nozzles 141 and 142 may be provided side by side on the upper side of each cassette 110. High-pressure air sprayed from the pair of air nozzles 141 and 142 blows the wafers W stored in the cassette 110. In order to sufficiently dry, it is preferable that the diameter of each air nozzle 141 and 142 is equal to or larger than the radius of the wafers W stored in the cassette 110. For example, in order to dry wafers W having a diameter of 200 mm, a pair of air nozzles 141 and 142 having a diameter of at least 100 mm may be provided to be spaced apart at a predetermined distance in the diameter direction of the wafer.

The vision sensor 150 is disposed on the upper side of each cassette 110, may be disposed between the air nozzles 141 and 142, and can measure edge defects of the wafers W stored in the cassette 110. . The vision sensor 150 can photograph the edges of the rotating wafers (W) and determine edge defects of the wafers (W) by comparing them with a pre-entered reference value through the photographed image.

The transfer 160 can move each air nozzle 141 and 142 and the vision sensor 150 on the upper side of each cassette 110 in the front and rear direction of the cassette 110. The transfer 160 may be a type of cylinder, and each air nozzle 141 and 142 and the vision sensor 150 may be mounted on the axis of the cylinder for reciprocating linear motion, but are not limited thereto.

The operation of the wafer edge inspection device configured as above is as follows.

When the cleaned wafers (W) are stored in each cassette 110 and each cassette 110 is stored in the chamber 120, as each roller 130 rotates, the wafers stored in each cassette 110 (W) rotates.

Each air nozzle 141 and 142, the vision sensor 150, and the transfer 160 may operate in conjunction with the roller 130. That is, while the roller 130 rotates, each air nozzle 141 and 142 sprays high-pressure air toward the wafers W, the vision sensor 150 photographs the edges of the wafers W, and the transfer ( 160 can move each air nozzle 141 and 142 and the vision sensor 150 in the forward and backward directions.

While the wafers (W) are rotating, each air nozzle (141, 142) sprays high-pressure air from the upper side toward the rotating wafers (W), and the vision sensor 150 sprays high-pressure air toward the rotating wafers (W) from the upper side. You can shoot edges continuously. Accordingly, it is possible to dry the wafer W evenly and accurately measure edge defects as long as each air nozzle 141 and 142 and the vision sensor 150 are in positions corresponding to each other.

In addition, the transfer 160 moves each air nozzle 141 and 142 and the vision sensor 150 from the upper front to the rear of the cassette 110, and the drying and edge defect measurement of the wafer W as described above can be continuously performed. there is. Therefore, each air nozzle 141, 142 and the vision sensor 150 dry evenly over the entire wafers W located at the moving position, that is, the wafers W stored in each cassette 110, while eliminating edge defects. It can be measured accurately.

As described above, the wafer edge inspection device of the embodiment can increase production efficiency by drying the wafers W stored in the cassette 110 at once and measuring edge defects of the wafers W at the same time. Additionally, by completely drying the wafers W, the flatness of the wafer can be accurately measured and the quality of the wafer can be managed more effectively.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications and variations will be possible to those skilled in the art without departing from the essential characteristics of the present invention.

Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but rather to explain it, and the scope of the technical idea of the present invention is not limited by these embodiments.

The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

110: Cassette 120: Chamber
130: Roller 141,142: Air nozzle
150: Vision sensor 160: Transfer
W: wafer

Claims (9)

A cassette in which a plurality of wafers are stored in a row with them standing at predetermined intervals in the front and rear directions;
a chamber in which the cassette is accommodated;
a roller that supports lower ends of the wafers stored in the cassette inside the chamber and rotates the wafers;
an air nozzle movably disposed inside the chamber and spraying air toward the wafers stored in the cassette; and
A vision sensor movably disposed inside the chamber and measuring edge defects of wafers stored in the cassette. According to paragraph 1,
The roller is,
It is disposed long in the front-back direction on the lower side of the cassette,
A wafer edge inspection device configured in a comb shape in which slit grooves supporting the lower ends of the wafers are provided at predetermined intervals. According to paragraph 1,
The air nozzle is,
Interlocked with the roller,
A wafer edge inspection device in which the air nozzle is operated to spray air toward the wafers as the roller rotates. According to paragraph 1,
The air nozzle is,
A pair is provided side by side at a predetermined interval on the upper side of the cassette,
A wafer edge inspection device configured to have a size at least equal to the radius of the wafer stored in the cassette. According to paragraph 1,
The vision sensor is,
Interlocked with the roller,
A wafer edge inspection device in which the vision sensor measures edge defects of the wafers as the roller rotates. According to paragraph 1,
The vision sensor is,
A wafer edge inspection device disposed above the center of the wafers stored in the cassette. According to clause 4,
The vision sensor is,
A wafer edge inspection device disposed between the air nozzles. According to any one of claims 1 to 7,
A transfer device that simultaneously moves the air nozzle and the vision sensor forward and backward on the upper side of the cassette. According to clause 8,
The transfer is,
A wafer edge inspection device consisting of a cylinder that moves the air nozzle and the vision sensor in the front and rear directions of the cassette.

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