US-12622218-B2 - Cassette lid opening device

US12622218B2US 12622218 B2US12622218 B2US 12622218B2US-12622218-B2

Abstract

A cassette lid opening device for use in a clean room apparatus configured for cooperation with a wafer cassette. The cassette lid opening device comprises a wall structure having a separation wall having a wall opening for transferring wafers therethrough, a cassette docking port, and a lid handler provided to the wall structure. The cassette docking port is arranged at a first side of the wall structure for docking a wafer cassette. The lid handler is movable relative to the wall opening and configured to engage a cassette lid of the wafer cassette docked in the cassette docking port. The cassette lid opening device further comprises a blower having an elongated, slit-like nozzle substantially spanning a height or a width of the wall opening and configured to blow a curtain-shaped jet stream of a purge gas into a cassette interior of the wafer cassette.

Inventors

Chris G.M. De Ridder

Assignees

ASM IP HOLDING B.V.

Dates

Publication Date: 20260505
Application Date: 20200722

Claims (16)

1 . A cassette lid opening device for use in a clean room apparatus configured for cooperation with a wafer cassette, wherein the wafer cassette comprises a cassette body defining a cassette interior for accommodating wafers oriented horizontally and having a cassette opening which is closeable with a cassette lid, wherein the cassette lid opening device comprises: a wall structure having a separation wall having a first side bounding a first space and having an opposite second side bounding a second space, the separation wall having a wall opening for transferring wafers therethrough; a cassette docking port arranged at the first side of the wall structure for docking the wafer cassette which is accommodated in the first space; and a lid handler provided to the wall structure, movable relative to the wall opening and configured to engage the cassette lid of the wafer cassette docked in the cassette docking port, the lid handler has a closed position in which the engaged cassette lid closes off the cassette body, and an open position in which the engaged cassette lid is spaced apart from the cassette body, the cassette lid opening device further comprising a blower having an elongated, slit-like nozzle substantially spanning a vertical height of the wall opening and configured to blow a curtain-shaped jet stream of a purge gas away from the separation wall in the direction of the first space into the cassette interior, wherein the lid handler is configured to move the engaged cassette lid laterally along a horizontal direction, wherein the horizontal direction is parallel to the separation wall; wherein the device further comprises: a door configured to close off the wall opening in the separation wall and being moveable with respect to the wall opening; a door handler connected to the door and configured to move the door to: a closed position in which in which the door closes off the wall opening; and an open position in which the door is moved laterally along the horizontal direction away from the wall opening; wherein the door handler is connected to the lid handler so as to move laterally together, and wherein the curtain-shaped jet stream is orthogonal to the horizontal plane and the horizontally oriented wafers and wherein the curtain-shaped jet stream moves laterally with the blower and the lid handler, wherein the curtain-shaped jet stream divides the cassette interior into a first volume on a side of the curtain-shaped jet stream in a direction of motion of the curtain-shaped jet stream and a second volume on a side of the curtain-shaped jet stream in a direction opposite of motion of the curtain-shaped jet stream, wherein the curtain-shaped jet stream is shaped such that no gas may flow from the first volume to the second volume, and wherein the second volume is substantially filled with purge gas.
2 . The cassette lid opening device according to claim 1 , wherein the blower is directly connected to the lid handler and is constructed and arranged moveable along substantially the entire vertical height of the cassette opening and configured to blow into the cassette interior.
3 . The cassette lid opening device according to claim 1 , wherein the blower is directly coupled to the lid handler such that the blower moves with the lid handler and is configured to blow past the engaged cassette lid into the cassette interior.
4 . The cassette lid opening device according to claim 1 , wherein the blower is directly connected to the lid handler, wherein the blower comprises a convex surface and wherein the elongated, slit-like nozzle is configured to blow the jet stream over the convex surface while the lid handler moves laterally.
5 . The cassette lid opening device according to claim 4 , further provided with a second purge gas source supplying a second purge gas in the surrounding of the convex surface, such that as a result of the Coanda effect at least part of the supplied second purge gas is entrained by the jet stream of purge gas being blown over the convex surface such that curtain-shaped jet stream is amplified and produces a uniform flow.
6 . The cassette lid opening device according to claim 1 , wherein the blower is configured to blow the curtain-shaped jet stream of the purge gas substantially across an entire depth of the cassette body.
7 . The cassette lid opening device according to claim 1 , wherein the wall structure comprises an exhaust port configured to remove a gas from the cassette interior when the lid handler is being moved from the closed to the open position and in the open position.
8 . The cassette lid opening device according to claim 7 , wherein the exhaust port comprises a venturi.
9 . The cassette lid opening device according to claim 1 , wherein the second space is a minienvironment of the clean room apparatus.
10 . An assembly for use in a clean room apparatus, comprising: a wafer cassette comprising: a cassette body defining a cassette interior for accommodating wafers and having a cassette opening; and a cassette lid configured to close off the cassette opening; and the cassette lid opening device according to claim 1 .
11 . The assembly according to claim 10 , wherein the wafer cassette comprises a FOUP.
12 . The cassette lid opening device according to claim 1 , wherein the blower is connected to the lid handler such that the curtain-shaped jet stream moves from a first lateral side of a cassette to the second lateral side of the cassette together with the lid handler.
13 . The cassette lid opening device according to claim 1 , wherein the cassette interior is filled with a first gas before moving the lid handler, and wherein the cassette interior is substantially purged of the first gas as the curtain-shaped jet stream moves from a first side of the cassette to a second side of the cassette.
14 . A method for opening and purging a wafer cassette, comprising: providing the wafer cassette at a cassette lid opening device, the wafer cassette comprising a cassette body defining a cassette interior for accommodating wafers oriented horizontally and having a cassette opening, wherein the cassette opening defines a vertical plane, the wafer cassette further comprising a cassette lid for closing off the cassette opening, wherein the cassette lid opening device comprises a wall structure having a separation wall having a first side bounding a first space and having an opposite second side bounding a second space, the separation wall having a wall opening for transferring wafers therethrough; wherein the cassette lid opening device comprises a door configured to close off the wall opening, and a cassette docking port arranged at the first side of the wall structure for docking the wafer cassette which is accommodated in the first space, wherein the cassette interior comprises a first gas; simultaneously moving the cassette lid and the door laterally along a horizontal direction with respect to the cassette body to an opened position to open the wafer cassette, wherein the horizontal direction is parallel to the vertical plane; and purging the cassette interior by blowing a curtain-shaped jet stream of a purge gas into the cassette interior while moving the curtain-shaped jet stream along the horizontal direction, wherein the curtain-shaped jet stream is orthogonal to the horizontal plane of the wafers and along substantially the entire height of the cassette opening, wherein the cassette interior is substantially purged of the first gas as the curtain-shaped jet stream moves from a first lateral side of the cassette to a second lateral side of the cassette.
15 . The method according to claim 14 , wherein the purging is effected at least during the moving of the cassette lid, wherein the moving of the curtain-shaped jet stream along substantially the entire height of the cassette opening and the moving of the cassette lid are coupled movements.
16 . The method according to claim 14 , wherein the curtain-shaped jet stream moves laterally from one side of the cassette interior to another, opposite side of the cassette interior.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application Ser. No. 62/881,158 filed Jul. 31, 2019 titled CASSETTE LID OPENING DEVICE, the disclosure of which is hereby incorporated by reference in its entirety. FIELD OF THE DISCLOSURE The present disclosure generally relates to a cassette lid opening device for use in a clean room apparatus. BACKGROUND Wafer cassettes are used in clean room environments to transport wafers to and from clean room apparatuses, such as vertical batch furnaces. An example of such a wafer cassette is the Front Opening Unified Pod, or FOUP, which is used to transport 300 mm wafers. A wafer cassette may be placed against a lid opening device which may be arranged at an opening in a wall of the clean room apparatus. The opening in the wall may be closeable by means of a door. The wall may, for example, separate a first environ, e.g., a cassette handling space, from a second environment, e.g., a wafer handling space. The lid opening device may be configured to open the lid of the wafer cassette and the door, whilst also preventing particles/contaminations from entering the wafer cassette and/or the second environment. Since wafer cassettes are not airtight, they may be filled with clean room air which is present in the clean room environment. When the second environment of the clean room apparatus uses a purge gas, such as nitrogen (N2), for example to reduce the levels of O2/H2O within the second environment, it is preferable that the clean room air in the wafer cassette be at least partly removed before the door may be opened. SUMMARY This summary is provided to introduce a selection of concepts in a simplified form. These concepts are described in further detail in the detailed description of example embodiments of the disclosure below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. It is an object to obtain a desired concentration level of purge gas within the wafer cassette relatively quick with a minimum amount of purge gas to be spent. To that end, there may be provided a cassette lid opening device. More particularly, there may be provided a cassette lid opening device for use in a clean room apparatus configured for cooperation with a wafer cassette. The wafer cassette may comprise a cassette body defining a cassette interior for accommodating wafers and may have a cassette opening which is closeable with a cassette lid. The cassette lid opening device may comprise a wall structure, a cassette docking port, and/or a lid handler provided to the wall structure. The wall structure may have a separation wall having a first side bounding a first space and having an opposite second side bounding a second space. The separation wall may have a wall opening for transferring wafers therethrough. The cassette docking port may be arranged at the first side of the wall structure for docking a wafer cassette which is accommodated in the first space. The lid handler may be movable relative to the wall opening and may be configured to engage the cassette lid of the wafer cassette docked in the cassette docking port. The lid handler may have a closed position in which the engaged cassette lid closes off the cassette body. The lid handler may have an open position in which the engaged cassette lid is spaced apart from the cassette body. The cassette lid opening device may further comprise an air pressure flow generator, e.g., a blower, having an elongated, slit-like nozzle substantially spanning a height or a width of the wall opening and may be configured to blow a curtain-shaped jet stream of a purge gas away from the separation wall in the direction of the first space into the cassette interior. There may also be provided an assembly for use in a clean room apparatus. The assembly may comprise a wafer cassette which may have a cassette body and a cassette lid. The cassette body may define a cassette interior for accommodating wafers and may have a cassette opening. The cassette lid may be configured to close off the cassette opening. The assembly may further comprise the cassette lid opening device according to the description. The present disclosure may also provide a method for opening and purging a wafer cassette. The method may comprise providing a wafer cassette which may include a cassette body defining a cassette interior for accommodating wafers, and which may have a cassette opening. The wafer cassette may further comprise a cassette lid for closing off the cassette opening. The method may further comprise moving the cassette lid with respect to the cassette body to an opened position to open the wafer cassette, and may comprise purging the cassette interior by blowing a curtain-shaped jet stream of a purge gas into the cassette interior while moving the curtain-shaped jet stream along sub