Automated material handling system for semiconductor manufacturing based on a combination of vertical carousels and overhead hoists

摘要

A highly efficient Automated Material Handling System (AMHS) that allows an overhead hoist transport vehicle to load and unload Work-In-Process (WIP) parts directly to/from one or more WIP storage units included in the system. The AMHS includes an overhead hoist transport subsystem and at least one vertical carousel stocker having a plurality of storage bins. The overhead hoist transport subsystem includes an overhead hoist transport vehicle traveling along a suspended track defining a predetermined route, which runs adjacent to the carousel stocker, thereby allowing the overhead hoist transport vehicle to access a WIP part directly from one of the storage bins. At least one of the storage bins includes a movable shelf operative to move laterally from a first position along the carousel path to a second position near the overhead hoist transport vehicle.

主权项

1. A method, comprising:
moving a moveable stage of an overhead hoist transport vehicle along a horizontal axis from a first position beneath an overhead rail to a second position adjacent to a side of the OHT vehicle; and moving, by a hoist coupled to the moveable stage, a gripper along a vertical axis to a position that is directly below the moveable stage, wherein the gripper is configured to hold a material unit; obtaining, by a gripper of the overhead transport (OTH) vehicle, the material unit from a suspended shelf; moving, by the overhead transport vehicle, the material unit held by the gripper from a starting position to an ending position wherein the starting position comprises a horizontal starting position and a vertical starting position, and the ending position comprises a horizontal ending position and a vertical ending position; wherein the hoist is configured to move the gripper along the vertical axis to a position that is directly below the moveable stage, when the moveable stage is in the first position; and wherein the hoist is configured to move the gripper along the vertical axis to a position that is directly below the moveable stage, when the moveable stage is in the second position that is adjacent to a side of the OHT vehicle; wherein the moveable stage is further configured to move the material unit configured to be held by the gripper from the horizontal starting position to the horizontal ending position, and the hoist is configured to move the material unit from the vertical starting position to the vertical ending position; wherein the starting position is at the suspended shelf and the ending position is the first position.