Semiconductor Substrate Backside Cutting Alignment via Exposed Groove
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Solution Overview
Problem
Current semiconductor chip manufacturing methods face challenges in accurately positioning cutting members for precise cutting, leading to inefficiencies in chip density and production yield due to limitations in alignment and depth control during the dicing process.
Innovation Solution
A method involving the formation of a microgroove and a deeper groove on the front surface of a semiconductor substrate, with the deeper groove serving as a positioning mark on the back surface, allows for precise alignment and cutting from the back surface towards the front, enabling increased chip density and improved yield by using the exposed groove as a mark for positioning the cutting member.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a groove is formed on the front surface for positioning, then alignment accuracy is improved, but the substrate structure becomes more complex and additional processing steps are required
Solution Approach 1:
The patent transitions the positioning mark from the front surface (2D plane) to the back surface (3D depth dimension) by forming a groove and then thinning the substrate to expose it. This dimensional change allows the positioning mark to be accessed from the cutting side without adding front surface complexity
Solution Approach 2:
The groove is formed on the front surface before substrate thinning, preparing the positioning structure in advance. This preliminary action ensures the groove is ready to be exposed as a positioning mark on the back surface before the actual cutting operation
2Ease of operation
If the cutting member positions from the back surface, then ease of operation is improved, but positioning precision deteriorates without a visible mark
Solution Approach 1:
The groove exposed on the back surface serves as an intermediary positioning mark that bridges the gap between back surface cutting accessibility and precise alignment requirements. This intermediate structure enables visual positioning without requiring front surface access
3Measurement precision
If the substrate is thinned to expose the groove, then positioning accuracy is improved, but the substrate strength decreases
Solution Approach 1:
The substrate is thinned partially to the extent necessary to expose the groove for positioning, but not excessively beyond what is needed. This controlled partial thinning achieves the positioning function while minimizing strength loss
Data Source
AI summary
Provided is a method for manufacturing a semiconductor chip including forming a groove on a front surface side along a cut area of a substrate, and a concave portion deeper than the groove on the front surface side as a positioning mark for a cutting member that performs cutting from a back surface of the substrate along the groove on the front surface side, thinning the substrate so as to reach the concave portion and not reach the groove on the front surface side, in the back surface of the substrate, positioning the cutting member from the back surface of the substrate by using the concave portion exposed on the back surface of the substrate as the positioning mark, and performing cutting from the back surface side of the substrate toward the groove on the front surface side of the substrate by using the positioned cutting member.