Semiconductor Scribe Region Layout for Crack-Controlled Wafer Dicing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor device manufacturers face challenges in wafer dicing due to rough edges of singulated dies, which can lead to cracks and reduced yield, particularly caused by heat and vibrations during laser dicing and tensile stress from tape expansion.
Innovation Solution
Incorporating a scribe region with a crack assist structure and crack stop structures to guide excessive force away from dies, absorb heat and vibrations, and mitigate tensile stress, thereby preventing crack propagation. The scribe region includes a crack assist structure at its center and crack stop structures on both sides, which are designed to manage the stress and force during the dicing process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If blade dicing or laser dicing is used to separate dies, then productivity is improved, but the edges of singulated dies become rough and subject to chipping
Solution Approach 1:
The scribe region is segmented into three distinct functional zones: a crack assist structure at the center to initiate and guide cracks, and crack stop structures on both sides to contain crack propagation. This segmentation allows the dicing process to maintain high productivity while protecting die edges through specialized structural zones.
Solution Approach 2:
The crack assist structure acts as an intermediary element between the dicing blade/laser and the die edges. It absorbs the cutting stress and guides crack propagation away from the die edges, preventing direct contact between the dicing tool and the vulnerable die boundaries.
2Productivity
If conventional dicing methods are used, then manufacturing speed is maintained, but cracks propagate to devices resulting in lower yield
Solution Approach 1:
The crack stop structures are pre-positioned in the scribe region before dicing occurs. These structures create predetermined barriers that actively prevent crack propagation toward the die edges during the dicing process, countering the harmful effect of crack formation before it can reach the devices.
Solution Approach 2:
The crack assist structure at the center of the scribe region intentionally facilitates crack formation by providing a controlled path for crack propagation. By converting the harmful crack formation into a controlled process centered in the scribe region, the actual die edges are protected from cracking, thus improving yield while maintaining dicing speed.
3Manufacturing precision
If scribe region structures are added to mitigate crack propagation, then die edge quality is improved, but device complexity increases
Solution Approach 1:
The additional structures are confined strictly to the scribe region, which is the area between dies that will be removed during dicing. This local placement allows the scribe region to have enhanced functionality for crack management without affecting the die structures themselves, thus improving die edge quality while limiting complexity to a non-critical area.
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
The proposed solution effectively reduces the propagation of cracks and enhances the quality of singulated dies by managing excessive force, heat, and stress, leading to improved yield and reduced roughness of die edges.
Implementation Method 1
a scribe region along which dies are separated that can mitigate crack propagation
Implementation Method 2
absorb heat and vibrations
Implementation Method 3
absorb heat and vibrations
Implementation Method 4
mitigate tensile stress
Data Source
AI summary
An apparatus includes a scribe region between a first die and a second die adjacent to each other in a first direction, the scribe region including a first crack stop region and a second crack stop region extending in a second direction that is perpendicular to the first direction, wherein the first and second dies are to be separated along a scribe line between the first and second crack stop regions, and a first structure in each of the first and second crack stop regions, the first structure including a plurality of first metal lines arranged in a hexagonal array in a plane defined by the first and second directions.