By-Die-Exposure for Edge Die Hole Patterning
Solution Overview
Problem
Conventional semiconductor fabrication techniques face challenges in patterning holes at the edge of wafers due to rounded wafer edges, leading to underexposure and deformities, as existing methods like By-Shot-Exposure do not allow for localized exposure adjustments within a shot area, compromising scanner throughput and hole integrity.
Innovation Solution
A method and system that divide a shot area into multiple shot portions, assign blind IDs, and provide additional exposure to edge shot portions while blocking non-edge shot portions, using a controller and light source to optimize exposure for edge dies on wafers with a rounded profile, ensuring accurate hole formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If standard exposure intensity is used for all dies on the wafer, then manufacturing process simplicity is maintained, but hole patterning precision deteriorates at wafer edge dies
Solution Approach 1:
The shot area is divided into multiple shot portions, with each portion assigned a blind ID. This segmentation allows different exposure intensities to be applied to different regions (center vs. edge dies) within the same shot, resolving the contradiction between process simplicity and patterning precision at wafer edges.
Solution Approach 2:
Different exposure intensities are applied to different locations within the shot area. Center dies receive standard exposure intensity while edge dies receive enhanced exposure intensity. This local quality approach ensures each region receives appropriate exposure for optimal hole patterning, maintaining precision without complicating the overall manufacturing process.
2Manufacturing precision
If By-Shot-Exposure is used to increase exposure on edge shots, then hole patterning precision improves, but scanner throughput deteriorates
Solution Approach 1:
The shot area is segmented into multiple shot portions with different blind IDs. This allows the scanner to process the entire shot area in a single pass while applying different exposure intensities to different portions, maintaining high throughput while achieving precise hole patterning at edge dies.
Solution Approach 2:
Instead of exposing all shot portions with enhanced intensity (excessive action), only edge shot portions receive additional exposure. This partial action approach maintains scanner throughput by avoiding full-shot re-exposure while still achieving the necessary precision improvement at critical edge regions.
3Reliability
If additional exposure is applied to edge shot portions, then hole integrity improves, but exposure process complexity increases
Solution Approach 1:
The shot area is divided into multiple shot portions, each assigned a blind ID. This segmentation enables automated differentiation between center and edge dies, allowing additional exposure to be applied only where needed. The complexity is managed through systematic classification rather than manual intervention.
Solution Approach 2:
The system automatically identifies edge shot portions and applies appropriate exposure intensity without requiring manual intervention or complex external control. The blind ID assignment and exposure differentiation are handled autonomously by the exposure system, improving hole integrity while limiting complexity increases to the automated classification process.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables the formation of holes with consistent dimensions across the wafer, improving hole integrity and reducing underexposure deformities by allowing for localized exposure adjustments, enhancing the precision and efficiency of semiconductor device fabrication.
Implementation Method 1
a beam of light is directed at a portion of the wafer through a mask to cover a spatial area called the 'shot' area
Data Source
AI summary
In accordance with the invention, there are semiconductor devices and methods of making semiconductor devices and holes. The method of making a semiconductor device can comprise forming a photoresist layer over a surface of a wafer, wherein the wafer comprises an edge that has a substantially rounded profile, an array of dies, and at least one edge die. The method can also comprise dividing a shot area into a plurality of shot portions and assigning a blind ID to each of the plurality of shot portions. The method can further comprise identifying one or more edge shot portions on the edge of the wafer for additional exposure; and exposing one or more times identified one or more edge shot portions on the edge of the wafer and blocking non-identified one or more non-edge shot portions.