CN-114270475-B - Substrate cleaning method and substrate cleaning device

CN114270475BCN 114270475 BCN114270475 BCN 114270475BCN-114270475-B

Abstract

The present invention relates to a substrate cleaning method and a substrate cleaning apparatus for cleaning a substrate such as a wafer. In the substrate cleaning method, a peripheral edge portion of a substrate (W) is held by a plurality of holding rollers (6), the plurality of holding rollers (6) are rotated about respective axes, the substrate (W) is rotated about the axes, and a two-fluid jet nozzle (2) is moved in a radial direction of the substrate (W), and a two-fluid jet composed of a mixture of a first liquid and a gas is introduced from the two-fluid jet nozzle (2) to a surface of the substrate (W), and when the two-fluid jet is introduced to the surface of the substrate (W), a fan-shaped jet composed of a second liquid is introduced from a spray nozzle (3) to the surface of the substrate (W), thereby forming a flow of the second liquid on the surface of the substrate (W). The fan jet exits from the dual fluid jet.

Inventors

KENJI KODERA
UCHIYAMA KEISUKE
Shan Benxiao
Yamano kunito

Assignees

株式会社荏原制作所

Dates

Publication Date: 20260505
Application Date: 20200713
Priority Date: 20190820

Claims (13)

1. A substrate cleaning method is characterized in that, The peripheral edge portion of the substrate is held by a plurality of holding rollers, The plurality of holding rollers are rotated about their respective axes to thereby rotate the substrate about the axis of the substrate, Introducing a two-fluid jet composed of a mixture of a first liquid and a gas from a two-fluid jet nozzle into a first region in a surface of the substrate while moving the two-fluid jet nozzle in a radial direction of the substrate, When the dual fluid jet is directed onto the surface of the substrate, a fan jet of a second liquid is directed from a spray nozzle into a second region within the surface of the substrate, forming a stream of the second liquid on the surface of the substrate, The second region is separated from the first region, The spray nozzle being located above the substrate and forming a flow of the second liquid towards the outside of the substrate in the second region, The flow of the second liquid toward the outside of the substrate washes away particulates from the substrate that float from the substrate by the dual fluid jet.
2. The method for cleaning a substrate according to claim 1, wherein, The angle of the spray nozzle relative to the surface of the substrate is in the range of 15 ° to 45 °.
3. The method for cleaning a substrate according to claim 1, wherein, The width of the fan-shaped jet is more than three-fourths of the radius of the substrate.
4. The method for cleaning a substrate according to claim 1, wherein, The fan-like jet is directed outwardly of the base plate.
5. The method for cleaning a substrate according to claim 1, wherein, The spray nozzle is located above the substrate.
6. The method for cleaning a substrate according to claim 1, wherein, The fan-shaped jet is introduced from the spray nozzle to the surface of the substrate while moving the spray nozzle, thereby forming a flow of the second liquid on the surface of the substrate.
7. The method for cleaning a substrate according to claim 6, wherein, The two-fluid jet nozzle and the spray nozzle are fixed to a common arm.
8. A substrate cleaning device is characterized by comprising: a plurality of holding rollers having a plurality of substrate holding surfaces for holding peripheral portions of the substrate and rotatable about their axes; a two-fluid jet nozzle configured to form a two-fluid jet composed of a mixture of a first liquid and a gas; A fan spray nozzle configured to form a fan-like jet of the second liquid, and A nozzle moving device configured to move the two-fluid jet nozzle in parallel, The two-fluid jet nozzle and the fan spray nozzle face a region surrounded by the plurality of substrate holding surfaces, and the fan spray nozzle faces a direction in which the fan-shaped jet does not strike the two-fluid jet.
9. The substrate cleaning apparatus according to claim 8, wherein, The fan spray nozzle has an angle in the range of 15 ° to 45 ° with respect to a plane passing through the plurality of substrate holding surfaces.
10. The substrate cleaning apparatus according to claim 8, wherein, The fan spray nozzle is configured to form the fan-shaped jet having a width of three-fourths or more of the radius of the substrate.
11. The substrate cleaning apparatus according to claim 8, wherein, The nozzle moving device includes an arm portion that holds the two-fluid jet nozzle and the fan spray nozzle.
12. A substrate cleaning method is characterized in that, The substrate is rotated around the axis of the substrate, Introducing a two-fluid jet composed of a mixture of a first liquid and a gas from a two-fluid jet nozzle into a first region in a surface of the substrate while moving the two-fluid jet nozzle in a radial direction of the substrate, When the dual fluid jet is directed onto the surface of the substrate, a fan jet of a second liquid is directed from a spray nozzle into a second region within the surface of the substrate, forming a stream of the second liquid on the surface of the substrate, The second region is separated from the first region, The spray nozzle being located above the substrate and forming a flow of the second liquid towards the outside of the substrate in the second region, The flow of the second liquid toward the outside of the substrate washes away particulates from the substrate that float from the substrate by the dual fluid jet.
13. A substrate cleaning device is characterized by comprising: A substrate holding unit that holds a substrate, has a plurality of substrate holding surfaces for holding a peripheral portion of the substrate, and rotates the substrate about an axis of the substrate; a two-fluid jet nozzle configured to form a two-fluid jet composed of a mixture of a first liquid and a gas; A fan spray nozzle configured to form a fan-like jet of the second liquid, and A nozzle moving device configured to move the two-fluid jet nozzle in parallel, The two-fluid jet nozzle and the fan spray nozzle face a region surrounded by the plurality of substrate holding surfaces, and the fan spray nozzle faces a direction in which the fan-shaped jet does not strike the two-fluid jet.

Description

Substrate cleaning method and substrate cleaning device Technical Field The present invention relates to a substrate cleaning method and a substrate cleaning apparatus for cleaning a substrate such as a wafer. Background In recent years, devices such as memory circuits, logic circuits, and image sensors (e.g., CMOS sensors) have been more highly integrated. In the step of forming these elements, foreign substances such as particles and dust adhere to the elements. Foreign matter adhering to the element may cause a short circuit or a circuit failure between wirings. Therefore, in order to improve the reliability of the element, it is necessary to clean the wafer on which the element is formed to remove foreign matter on the wafer. Foreign matter such as the above-mentioned fine particles and dust is also attached to the back surface (non-element surface) of the wafer. When such foreign matter adheres to the back surface of the wafer, the wafer is deviated from the stage reference surface of the exposure apparatus or the wafer surface is inclined with respect to the stage reference surface, and as a result, pattern formation deviation and focus distance deviation occur. Therefore, there is a method of introducing a two-fluid jet composed of a mixed fluid of a liquid and a gas to the surface (front side or back side) of a wafer to clean the surface of the wafer. When the dual fluid jet cleaning is performed, the peripheral edge portion of the wafer is held by the chuck with the chuck being rotated around the axis of the wafer, and the dual fluid jet is sprayed from the nozzle onto the wafer surface. Further, by swinging (scanning) the nozzle along the radial direction of the wafer, a two-fluid jet stream can be introduced to the entire surface of the wafer being rotated. But when the nozzle is located over the peripheral portion of the wafer, the dual fluid jets may strike the jaws of the chuck, resulting in a large amount of liquid splatter. In order to prevent such liquid from splashing, a cleaning apparatus of a type in which a peripheral edge portion of a wafer is held by a plurality of rollers instead of a chuck, and the wafer is rotated by rotating the rollers has been proposed. With this type of cleaning apparatus, since the roller itself is fixed in position, the two-fluid jet does not collide with the roller even when the nozzle is located above the peripheral edge portion of the wafer. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2017-147334 Problems to be solved by the invention However, compared with the chuck type, the roller type cleaning apparatus cannot rotate the wafer at a high speed (typically, 150min -1 at maximum). Thus, in order to clean the entire surface of the wafer, it is necessary to slow down the moving speed of the nozzle. As a result, the time required for one reciprocation (one scan) of the nozzle becomes long, and the portion of the wafer which is not in contact with the liquid becomes a semi-dry state. In addition, since the rotation speed of the wafer is low, no strong centrifugal force acts on the liquid on the wafer, and fine particles floating by the two-fluid jet flow remain on the wafer. Disclosure of Invention Accordingly, the present invention provides a substrate cleaning method and a substrate cleaning apparatus capable of preventing a substrate such as a wafer from being semi-dried and reliably removing particles floating by a dual fluid jet from the surface of the substrate. (Means for solving the problems) In one embodiment, a substrate cleaning method is provided, in which a peripheral edge portion of a substrate is held by a plurality of holding rollers, the plurality of holding rollers are rotated about their respective axes, the substrate is rotated about its axis, a two-fluid jet nozzle is moved in a radial direction of the substrate, a two-fluid jet composed of a mixture of a first liquid and a gas is introduced from the two-fluid jet nozzle to a surface of the substrate, a fan-shaped jet composed of a second liquid is introduced from a spray nozzle to the surface of the substrate when the two-fluid jet is introduced to the surface of the substrate, and a flow of the second liquid is formed on the surface of the substrate, and the fan-shaped jet is separated from the two-fluid jet. One way is that the angle of the spray nozzle relative to the surface of the substrate is in the range of 15 ° to 45 °. In one embodiment, the width of the fan-shaped jet is three quarters or more of the radius of the substrate. One embodiment is such that the fan-like jet is directed outward of the substrate. One way is that the spray nozzle is located above the substrate. In one embodiment, the fan-shaped jet is introduced from the spray nozzle to the surface of the substrate while moving the spray nozzle, so that a flow of the second liquid is formed on the surface of the substrate. In one embodiment, the two-fluid jet nozzle