US-12617050-B2 - Processing machine and unloading method of workpiece

US12617050B2US 12617050 B2US12617050 B2US 12617050B2US-12617050-B2

Abstract

A processing machine has a holding unit, which includes a holding surface, a suction valve, an air ejection valve, a water ejection valve, a plurality of suction openings, and a suction-openings suction valve that establishes or interrupts communication between the suction openings and a suction source. An unloading method of a wafer in the processing machine includes a separation step of separating the wafer from the holding surface by closing the suction valve and opening the air ejection valve and the water ejection valve such that a mixed fluid of air and water is supplied to the holding surface, and an unloading step of unloading, from the holding surface, the wafer separated from the holding surface. The separation step includes a drawing step of opening the suction-openings suction valve and drawing the mixed fluid outside of the holding surface.

Inventors

Jiro Genozono

Assignees

DISCO CORPORATION

Dates

Publication Date: 20260505
Application Date: 20240313
Priority Date: 20230324

Claims (2)

1 . A processing machine comprising: a holding unit that has a holding surface and holds a workpiece under suction on the holding surface; a processing unit that processes the workpiece held under suction on the holding surface; and a controller that controls the holding unit and the processing unit, wherein the holding unit includes a suction valve that establishes or interrupts communication between the holding surface and a suction source, a fluid ejection valve that establishes or interrupts communication between the holding surface and a fluid supply source, a plurality of suction openings that are arranged in a ring pattern outside of the holding surface and draw fluid ejected from the holding surface, and a suction-openings suction valve that establishes or interrupts communication between the suction openings and the suction source, and the controller is configured to control closing of the suction valve, opening of the fluid ejection valve, and opening of the suction-openings suction valve.
2 . An unloading method of a workpiece for unloading the workpiece, the workpiece being held under suction on a holding surface of a holding unit communicating with a suction source, from the holding surface, with use of a processing machine, the processing machine including a holding unit having a holding surface, a processing unit that processes the workpiece held under suction on the holding surface, and a controller configured to control the holding unit and the processing unit, the holding unit including a suction valve that establishes or interrupts communication between the holding surface and the suction source, a fluid ejection valve that establishes or interrupts communication between the holding surface and a fluid supply source, a plurality of suction openings that are arranged in a ring pattern outside of the holding surface and draw fluid ejected from the holding surface, and a suction-openings suction valve that establishes or interrupts communication between the suction openings and the suction source, the unloading method comprising: a separation step of separating the workpiece from the holding surface by closing the suction valve and opening the fluid ejection valve such that the fluid is supplied to the holding surface; and an unloading step of unloading, from the holding surface, the workpiece separated from the holding surface, wherein the separation step includes a drawing step of opening the suction-openings suction valve and drawing the fluid outside of the holding surface.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a processing machine for processing a workpiece such as a wafer held on a holding surface of a holding unit, and also to an unloading method of the workpiece by separating, from the holding surface of the holding unit, the workpiece processed by the processing machine. Description of the Related Art For example, a grinding machine that grinds a workpiece such as a wafer applies grinding processing to the workpiece at its upper surface by establishing communication of a holding surface of a chuck table of a holding unit with a suction source, and bringing grinding stones, which are secured in an annular pattern, into contact with the upper surface of the workpiece held under suction on the holding surface while rotating the grinding stones. After completion of the grinding processing on the workpiece, a mixed fluid of water and air is ejected from the holding surface of the chuck table to separate the workpiece from the holding surface, and the separated workpiece is unloaded by a transfer pad (see, for example, Japanese Patent Laid-open No. 2022-025341). In Japanese Patent Laid-open No. 2013-184269, a holding release method of a plate-shaped workpiece, such as a wafer, held on a holding surface of a holding table when unloading the plate-shaped workpiece is proposed. According to the holding release method, a supply pressure of a mixed fluid from a fluid supply source to the holding surface is detected, thus ensuring release of a suction holding force from the holding table and hence separation of the plate-shaped workpiece from the holding surface of the holding table irrespective of differences in the size of a holding pad of unloading means or in the thickness of the plate-shaped workpiece. SUMMARY OF THE INVENTION When the mixed fluid is ejected from the holding surface to separate the workpiece from the holding surface for the unloading of the workpiece, the mixed fluid contains processing debris drawn to the holding surface during the processing of the workpiece. The mixed fluid with the processing debris contained therein blows out from an outer periphery of the workpiece floating from the holding surface, so that the workpiece is contaminated at its side surface and upper surface with the processing debris. Hence, there is a need to remove the processing debris by rinsing the workpiece after its separation from the holding surface. This requires a longer rinsing time, leading to a problem of low efficiency. The present invention therefore has as its objects the provision of a processing machine and an unloading method of a workpiece that, when the fluid is ejected from a holding surface to separate the workpiece from the holding surface for the unloading of the workpiece, can prevent splashing of fluid with processing debris contained therein and can perform rinsing of the workpiece in a short period of time. In accordance with a first aspect of the present invention, there is provided a processing machine including a holding unit that has a holding surface and holds a workpiece under suction on the holding surface, a processing unit that processes the workpiece held under suction on the holding surface, and a controller that controls the holding unit and the processing unit. The holding unit includes a suction valve that establishes or interrupts communication between the holding surface and a suction source, a fluid ejection valve that establishes or interrupts communication between the holding surface and a fluid supply source, a plurality of suction openings that are arranged in a ring pattern outside of the holding surface and draw fluid ejected from the holding surface, and a suction-openings suction valve that establishes or interrupts communication between the suction openings and the suction source. The controller is configured to control closing of the suction valve, opening of the fluid ejection valve, and opening of the suction-openings suction valve. In accordance with a second aspect of the present invention, there is provided an unloading method of a workpiece for unloading the workpiece, the workpiece being held under suction on a holding surface of a holding unit communicating with a suction source, from the holding surface, with use of a processing machine. The processing machine includes a holding unit having a holding surface, a processing unit that processes the workpiece held under suction on the holding surface, and a controller configured to control the holding unit and the processing unit. The holding unit includes a suction valve that establishes or interrupts communication between the holding surface and the suction source, a fluid ejection valve that establishes or interrupts communication between the holding surface and a fluid supply source, a plurality of suction openings that are arranged in a ring pattern outside of the holding surface and draw fluid ejected from the holding surface,