Overhead Substrate Handling System for Semiconductor Tool Layout
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor manufacturing, existing material handling systems face inefficiencies due to long delivery times between tools, congestion, and the need for frequent wafer carrier movements to and from storage, which disrupt the process flow and reduce throughput.
Innovation Solution
A matrix material handling system (MMHS) with an overhead rack, side rails, cross rails, and transport vehicles that allow for direct access to tool load ports through interior and periphery windows, enabling efficient movement and storage of wafer pods, reducing the need for conventional stockers and allowing for a denser tool layout, increased throughput, and shared buffering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional wafer storage systems are used with frequent movements to and from storage, then wafer carriers can be stored, but process flow is disrupted and throughput is reduced
Solution Approach 1:
The patent extracts the storage function from the material handling system by providing dedicated stocker positions where wafer carriers can be stored without requiring material handling vehicles to travel to and from central storage areas. This separation allows storage operations to occur independently without disrupting the material handling flow between tools.
Solution Approach 2:
The patent implements preliminary action by pre-positioning wafer carriers in stocker positions adjacent to tools before they are needed for processing. This allows tools to quickly access carriers without waiting for long-distance travel from central storage, thereby maintaining continuous process flow and maximizing throughput.
2Adaptability or versatility
If material handling vehicles travel long distances to access tools and storage, then all tools and storage can be accessed, but delivery time increases and tool utilization decreases
Solution Approach 1:
The patent segments the material handling system into multiple independent vehicles operating on different overhead rails, with each vehicle serving specific tool groups and storage areas. This segmentation allows parallel operations where multiple vehicles can simultaneously service different locations, reducing overall delivery time while maintaining comprehensive tool access.
Solution Approach 2:
The patent transitions from ground-based material handling to an overhead three-dimensional system. Vehicles travel along overhead rails positioned above the fabrication floor, allowing them to access tools from above through vertical windows. This dimensional change enables shorter travel paths and eliminates congestion on the fabrication floor while maintaining access to all tools and storage positions.
3Productivity
If overhead material handling system is implemented, then delivery time is minimized and throughput increases, but system complexity and initial cost increase
Solution Approach 1:
The patent implements universal, multi-functional material handling vehicles that can service multiple different tools and storage positions along their rail paths. Each vehicle is designed to handle various wafer carrier types and can access both stocker positions and tool load ports, reducing the need for specialized vehicles for each tool and thereby managing system complexity while maintaining high throughput.
Data Source
AI summary
A method for operating a material handling system including an overhead rack defining a plurality of storage positions, first and second side rails disposed above the overhead rack, a first cross rail movably coupled to the first and second side rails, and a first transport vehicle movably coupled to the first cross rail includes positioning the first transport vehicle above at least one interior window defined in the overhead rack. At least a portion of the first transport vehicle is descended through the interior window to interface with a first load port of a first tool disposed below the overhead rack. The first transport vehicle is positioned above at least one periphery window defined in the overhead rack. At least a portion of the first transport vehicle is descended through the periphery window to interface with a second load port of a second tool disposed below the overhead rack.