JP2003007668A - Apparatus and method for cleaning semiconductor wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and method for cleaning a semiconductor wafer, which can efficiently clean the peripheral part of a wafer on which polishing dusts are apt to adhere. SOLUTION: The apparatus for cleaning a peripheral edge E of a semiconductor wafer W includes a water droplet flow ejection mechanism 3, which has a plurality of ejection nozzles 2. the nozzles are positioned at intervals of equal spacing, in the peripheral direction of the wafer W for blowing a water mist flow J, at a flow rate of 250 m/sec against a peripheral edge E of the wafer for its cleaning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer cleaning apparatus and a cleaning method for cleaning a peripheral portion of a wafer before or after polishing a surface or a chamfered surface of a silicon wafer or the like.

[0002]

2. Description of the Related Art As a process for processing or polishing a semiconductor wafer such as a silicon wafer, there are, for example, a mirror surface polishing process, a chamfering polishing process for forming a chamfered surface at a peripheral portion, and a chamfered surface mirror polishing process. In these processing steps and polishing steps, a large amount of various particles such as polishing scraps and abrasives are generated and adhered during the steps, so that the wafer is cleaned after the polishing is completed.

Conventionally, as wafer cleaning after the end of the process, for example, in mirror polishing of the surface, the wafer surface is cleaned by scrubbing polishing scraps with a brush or an interface puff after polishing, and in chamfering surface processing. The wafer removed from the polishing apparatus was immersed in cleaning water while being mounted on a rack, and the dip cleaning was performed while stirring the cleaning water.

[0004]

The above-mentioned conventional wafer cleaning technique has the following problems. That is, the surface of the wafer can be cleaned by cleaning with a brush or the like, but at the peripheral edge of the wafer, polishing debris and the like easily accumulate between the polishing plate and the polishing plate, and the brush is hard to hit. , Could not be washed thoroughly. Further, if the polishing scraps adhere to the brush or the like, the wafer may be scratched. Further, simply dipping the wafer in the cleaning water and performing the dip cleaning cannot sufficiently remove the polishing debris.

The present invention has been made in view of the above problems, and provides a semiconductor wafer cleaning apparatus and a cleaning method capable of efficiently cleaning the peripheral portion of a wafer to which polishing debris and the like tend to adhere. With the goal.

[0006]

The present invention has the following features to attain the object mentioned above. That is, the semiconductor wafer cleaning apparatus of the present invention is an apparatus for cleaning the peripheral portion of a semiconductor wafer, and the flow velocity is 250 m at the peripheral portion.
It is characterized by comprising a water droplet jetting mechanism for jetting a water droplet jet of / s or more from an jet nozzle to wash. Also,
A method of cleaning a semiconductor wafer according to the present invention is a method of cleaning a peripheral portion of a semiconductor wafer, wherein a flow velocity 2 is applied to the peripheral portion.
It is characterized in that a water droplet flow of 50 m / s or more is sprayed from an injection nozzle for cleaning.

In these semiconductor wafer manufacturing apparatus and cleaning method, since a water droplet stream having a flow rate of 250 m / s or more is sprayed from the jet nozzle to the peripheral portion of the wafer for cleaning, the peripheral portion which cannot be removed only by immersing it in cleaning water. The adhered polishing debris and the like can be removed without being damaged by the collision of the ultra-high-speed water droplet flow and can be washed away. In addition, in the water droplet flow of less than 250 m / s,
It is not possible to obtain the collision energy sufficient to blow the polishing debris away against the adhesive force of the polishing debris.

Further, in the semiconductor wafer manufacturing apparatus of the present invention, the water droplet jetting mechanism arranges the plurality of jet nozzles at equal intervals in the circumferential direction of the semiconductor wafer, and these jet nozzles or semiconductor wafers It is preferable to have a moving mechanism for rotating the semiconductor wafer about its central axis. That is, in this semiconductor wafer manufacturing apparatus, by the moving mechanism, a plurality of injection nozzles or semiconductor wafers arranged at equal intervals in the circumferential direction of the semiconductor wafer are rotated around the central axis of the semiconductor wafer, so that the entire peripheral portion The cleaning can be performed efficiently without the need to rotate 360 °, and when rotated once or more, a plurality of injection nozzles can perform repeated cleaning a plurality of times to obtain a high cleaning effect. .

Further, in the semiconductor wafer manufacturing apparatus of the present invention, the water droplet jetting mechanism changes the angle of the water droplet jet with respect to the peripheral portion by relatively moving the semiconductor wafer and the jet nozzle. It is preferable to have a mechanism. That is, in this semiconductor wafer manufacturing apparatus, the angle varying mechanism moves the semiconductor wafer and the jet nozzle relative to each other to change the angle of the water droplet flow with respect to the peripheral edge. In the formed peripheral portion, since the angle at which the water droplet flow hits changes, it becomes possible to remove the adhering matter by colliding the water droplet flow from multiple directions even in a portion that was difficult to drop from one direction.

The semiconductor wafer manufacturing apparatus of the present invention further comprises an inspection mechanism for inspecting the peripheral portion of the semiconductor wafer for the presence and position of deposits over the entire circumference in advance.
It is preferable that the water droplet flow ejecting mechanism blows the water droplet flow on the position of the deposit detected based on the inspection result of the inspection mechanism more or more strongly than other positions.
That is, in this semiconductor wafer manufacturing apparatus, by spraying a water droplet flow more or more strongly to the position of the deposit detected based on the inspection result by the inspection mechanism, the deposit is removed more efficiently. be able to.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of a semiconductor wafer cleaning apparatus and cleaning method according to the present invention will be described below with reference to FIGS. In these drawings, reference numeral 1 is a polishing plate, 2 is an injection nozzle, 3 is a water droplet flow injection mechanism, 4 is a moving mechanism, and 5 is a supply source.

1 and 2 show an apparatus for manufacturing a semiconductor wafer according to the present invention, in which the surface of a silicon wafer (semiconductor wafer) W is subjected to CMP (Chemical Mechanical).
After the mirror polishing by ical polishing, especially the peripheral edge H of the wafer W is cleaned. The wafer W
The peripheral edge portion H of C is chamfered. In this cleaning device, a water droplet flow J having a flow velocity of 250 m / s or more is applied to the peripheral portion E of the wafer H after polishing placed on the polishing plate 1 at a flow rate of 250 m / s or more.
It is provided with a water droplet jetting mechanism 3 which sprays from one jet nozzle 2 to wash.

The water droplet jetting mechanism 3 arranges the three jetting nozzles 2 above the polishing plate 1 at equal intervals in the circumferential direction of the wafer W (that is, at intervals of 120 ° around the wafer center axis). Moving mechanism 4 having a motor (not shown) or the like for rotating the jet nozzle 2 of FIG. 1 around the central axis O of the wafer W, and the jet nozzle 2 connected to each jet nozzle 2.
In order to eject the water droplet flow J having a flow velocity of 250 m / s or more from the above, the jet nozzle 2 is provided with a supply source 5 for mixing the washing water and the gas and supplying the mixture at high pressure.

It should be noted that the moving mechanism 4 is provided for each of the injection nozzles 2.
The position and orientation of can be changed arbitrarily. Further, the supply source 5 can arbitrarily adjust each flow rate and each pressure of the cleaning water and the gas so that the water droplet flow J from the injection nozzle 2 becomes an ultra-high speed jet water flow, and at least the flow velocity 250 is set.
The water droplet flow J is set to be m / s or more. In addition, the supply source 5 and the injection nozzle 2 have a
The particle size is set to about 0 μm.

Next, a method of cleaning the peripheral portion E of the wafer W by the cleaning apparatus of this embodiment will be described.

First, after finishing the mirror polishing of the surface, the moving mechanism 4 of the water droplet jetting mechanism 3 is driven to dispose the jet nozzle 2 toward the surface of the wafer W on the polishing plate 1, and the water droplet jet J is applied. Particles such as polishing scraps and abrasive particles that are sprayed on the surface of W and remain on the surface are blown away and removed. It should be noted that the water droplet stream J may be jetted toward the exposed portion of the polishing plate 1 and the polishing debris and the like on the polishing plate 1 may be washed off at the same time. In this case, the load associated with cleaning the polishing plate 1 can be reduced.

Next, the moving mechanism 4 causes the three spray nozzles 2 to be arranged at equal intervals in the circumferential direction of the wafer W.
The jet nozzles 2 are arranged above and the jet nozzles 2 are provided at the peripheral edge E of the wafer W.
Turn to. Then, the cleaning water and the gas are supplied from the supply source 5 to the injection nozzle 2 at a predetermined flow rate and pressure, and the injection nozzle 2
The water droplet flow J having a flow velocity of 250 m / s or more is jetted from the nozzle and sprayed on the peripheral edge E. Further, the moving mechanism 4 rotates the jet nozzles 2 at least 120 ° or more around the central axis O of the wafer W while keeping the mutual intervals constant.

At this time, the polishing debris and the abrasive particles and the like adhering to the peripheral edge E and the particles and the like accumulated between the peripheral edge E and the polishing plate 1 are blown away by the collision of the super-high-speed water droplet stream J. To be removed.

Furthermore, the wafer W is moved by the moving mechanism 4.
By rotating three jet nozzles 2 arranged at equal intervals in the circumferential direction of the wafer W around the central axis O of the wafer W, it is not necessary to rotate 360 ° in order to clean the entire circumference of the peripheral edge portion E, which is efficient. Can be washed. It should be noted that when the ejection nozzle 2 is rotated for one revolution or more, the three ejection nozzles 2
As a result, the cleaning is repeated a plurality of times, and the particles and the like can be removed more reliably.

Next, a second embodiment of the semiconductor wafer cleaning apparatus and cleaning method according to the present invention will be described with reference to FIG.

The difference between the second embodiment and the first embodiment is that the cleaning apparatus of the first embodiment cleans the peripheral portion E of the wafer W after the surface mirror finishing on the polishing plate 1. On the other hand, the cleaning device of the second embodiment is a device for cleaning the peripheral portion E after chamfering, and as shown in FIG. 3, the water droplet jetting mechanism 13 includes two jet nozzles 2 and these jet nozzles 2 are provided. The jet nozzle 2 sprays the water droplet stream J onto the peripheral edge E at different angles.

That is, in this embodiment, one of the two jet nozzles 2 is arranged above the wafer W so as to jet the water droplet stream J toward the peripheral edge portion E obliquely below, and the other one. Is disposed below the wafer W and is provided so as to jet the water droplet stream J toward the peripheral edge E diagonally above. In addition, the water droplet flow ejecting mechanism 13 moves the two ejection nozzles 2 to change the angle thereof and changes the angle of the water droplet flow J with respect to the peripheral portion E (angle varying mechanism).
14 are provided.

Further, in the cleaning apparatus of this embodiment, the rotating mechanism 16 such as a motor for rotating the wafer W supported by a supporting member (not shown) about its central axis, and the peripheral portion E of the wafer W are preliminarily covered with the entire circumference. And an inspection mechanism 17 for inspecting the presence and position of adhered substances. In addition,
The inspection mechanism 17 uses, for example, a CCD camera or the like to detect the peripheral portion E.
It is set so that the foreign matter can be observed, the foreign matter is detected in association with the rotation mechanism 16, and the presence or absence and the position of the foreign matter are stored. Further, the moving mechanism 14 of the water droplet jetting mechanism 13 is set so as to spray the water droplet jet J to the position of the adhering matter detected based on the inspection result by the inspection mechanism 17 more or more strongly than other positions.

Next, a method of cleaning the peripheral portion E of the wafer W by the cleaning apparatus of this embodiment will be described.

First, the rotating mechanism 16 rotates the wafer W at least once, and the inspection mechanism 17 detects and stores the presence or absence and the position of the deposit on the entire circumference of the peripheral edge E.

Next, the wafer W is rotated by the rotating mechanism 17, and the two jetting nozzles 2 are tilted by the moving mechanism 14 at a predetermined angle (for example, 45 ° with respect to the front surface and the back surface of the wafer W). The cleaning water and the gas are mixed from the supply source 5 and supplied at high pressure to the respective injection nozzles 2, and the ultrahigh-speed water droplet stream J is jetted toward the peripheral edge portion E.
At this time, since the water droplet flow J collides with the peripheral portion E from two directions, that is, obliquely upward and obliquely downward, a higher cleaning effect can be obtained as compared with the water droplet flow from only one direction.

During the above cleaning, the moving mechanism 14
Controls the supply source 5 and the rotation mechanism 16 so that the water droplet flow J is sprayed to the position of the deposit detected based on the inspection result by the inspection mechanism 17 more or more strongly than other positions. For example, when the water droplet flow J hits the position where the adhering matter is detected, the supply source 5 is controlled to increase the flow velocity of the water droplet flow J more than other positions so as to make the water droplet flow J collide more strongly or rotate. The rotation speed of the wafer W is made slower than other positions by the mechanism 16 so that the water droplet flow J collides for a longer time, and further, the rotation of the wafer W is temporarily stopped and the moving mechanism 14 causes the two jet nozzles to move. The water droplet flow J is made to collide with the peripheral portion E at various ejection angles while changing the inclination of 2.

As described above, in the present embodiment, after the chamfered surface is processed, the peripheral edge portion E having the chamfered surface can be efficiently cleaned by the water droplet flow J colliding from different angles in at least two directions. By spraying the water droplet flow J to the position of the deposit detected based on the inspection result of 17 more or more strongly than other positions, the deposit can be removed more efficiently.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the first embodiment described above, three injection nozzles are adopted, and in the second embodiment two injection nozzles are adopted, but the number of injection nozzles is not particularly limited. Needless to say, the larger the number of injection nozzles, the more efficiently the cleaning can be performed.

Further, the cleaning apparatus of each of the above-mentioned embodiments was adopted for cleaning after the wafer surface was mirror-polished and after the peripheral portion was chamfered, but other steps (for example, chamfered mirror-polishing) were performed. It may be applied before and after. Also,
Although the peripheral portion of the silicon wafer is cleaned, the peripheral portion of another semiconductor wafer, for example, a wafer such as GaAs (gallium arsenide) may be cleaned.

In the second embodiment, the angle of the spray nozzle is changed by the moving mechanism, but a mechanism for changing the angle of the wafer may be provided if the spray angle is relatively changed. In addition to the above-mentioned jet nozzle for cleaning the peripheral portion, a jet nozzle for cleaning the front surface or the back surface of the wafer may be separately provided. Further, although the water droplet flow is a mixture of cleaning water and gas, the cleaning water may include not only pure water but also various chemical solutions.

[0032]

According to the semiconductor wafer cleaning apparatus and the cleaning method of the present invention, the flow velocity is 250 m / s at the peripheral portion of the wafer.
Since the above water droplet flow is sprayed from the jet nozzle to perform cleaning, it is possible to remove adhering polishing debris and the like on the peripheral edge that cannot be removed simply by immersing it in cleaning water without damaging the wafer by collision with the ultra-high-speed water droplet flow. it can. Therefore,
By adhering to the peripheral portion, which is a region smaller than the front and back surfaces and easily soiled, with an ultra-high-speed water droplet flow, the adhered substances can be removed efficiently and reliably.

[Brief description of drawings]

FIG. 1 is a schematic front view showing a configuration of a cleaning device according to a first embodiment of the present invention.

FIG. 2 is a schematic plan view showing the configuration of the cleaning apparatus according to the first embodiment of the present invention.

FIG. 3 is a schematic front view showing the configuration of a cleaning device according to a second embodiment of the present invention.

[Explanation of symbols]

2 injection nozzles 3, 13 Water drop jetting mechanism 4, 14 Moving mechanism (angle variable mechanism) 5 supply sources 17 Inspection mechanism E Wafer periphery J water droplet flow W Silicon wafer (semiconductor wafer)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tomoya Tanaka             3-5-1, Otemachi, Chiyoda-ku, Tokyo             Ryo Material Silicon Co., Ltd. (72) Inventor Tsuyoshi Maeda             3-5-1, Otemachi, Chiyoda-ku, Tokyo             Ryo Material Silicon Co., Ltd. (72) Inventor Kiyosato Nagai             3-5-1, Otemachi, Chiyoda-ku, Tokyo             Ryo Material Silicon Co., Ltd. F-term (reference) 3C047 FF08 GG00                 4F033 AA04 BA04 CA01 DA01 EA02                       EA03 LA12                 4F042 AA07 AA29 BA05 BA06 BA10                       BA11 CB03 CB08 CB19 DF09                       DF32 EB09 EB13 EB18

Claims (6)

[Claims] 1. An apparatus for cleaning a peripheral portion of a semiconductor wafer, comprising a water droplet jetting mechanism for spraying a water droplet stream having a flow velocity of 250 m / s or more from an jet nozzle to the peripheral portion. Semiconductor wafer cleaning equipment. 2. The semiconductor wafer cleaning apparatus according to claim 1, wherein the water droplet jetting mechanism has a plurality of jet nozzles arranged at equal intervals in a circumferential direction of the semiconductor wafer, An apparatus for cleaning a semiconductor wafer, comprising a moving mechanism for rotating the semiconductor wafer around a central axis of the semiconductor wafer. 3. The semiconductor wafer cleaning apparatus according to claim 1, wherein the water droplet jetting mechanism moves the semiconductor wafer and the jet nozzle relatively to each other, and the angle of the water droplet jet with respect to the peripheral portion. An apparatus for cleaning a semiconductor wafer, which is equipped with a variable angle mechanism for changing the temperature. 4. The semiconductor wafer cleaning apparatus according to claim 1, wherein the water droplet jetting mechanism includes a plurality of jet nozzles, and the jet nozzles have different angles with respect to the peripheral portion. A semiconductor wafer cleaning apparatus, characterized in that the water droplet stream is sprayed on the substrate. 5. The apparatus for cleaning a semiconductor wafer according to claim 1, further comprising an inspection mechanism for inspecting the peripheral portion of the semiconductor wafer for the presence and position of deposits over the entire circumference in advance. A cleaning apparatus for a semiconductor wafer, wherein the mechanism sprays the water droplet flow on the position of the deposit detected based on the inspection result of the inspection mechanism more or more strongly than at other positions. 6. A method of cleaning a peripheral edge of a semiconductor wafer, which comprises cleaning the peripheral edge with a water droplet flow having a flow rate of 250 m / s or more from a jet nozzle.