Conductive Post Width Variation for Semiconductor Assembly Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor device packaging, particularly in package-on-package structures, controlling the size and dimension of solder balls is challenging, leading to issues with assembly and alignment, and copper pillars, while more uniform, still face manufacturing limitations as technologies advance and device sizes shrink.
Innovation Solution
A substrate design featuring a conductive post with a first portion and a second portion, where the second portion has a greater width than the first, exposed by a dielectric layer, facilitating precise electrical connections and uniform height across multiple layers, enabling improved assembly and alignment in semiconductor device packaging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If solder balls are used to connect upper substrate to lower substrate, then electrical connections are established, but size and dimension control is challenging affecting assembly precision
Solution Approach 1:
The conductive post is divided into two distinct portions: a first portion with a first width and a second portion with a second width greater than the first width. This segmentation allows different functional requirements to be met - the narrower first portion enables precise alignment and positioning, while the wider second portion provides stable electrical connection and mechanical support.
2Manufacturing precision
If copper pillars are used to replace solder balls, then uniformity in height is improved and width and pitch are reduced, but manufacturing limitations persist as device sizes shrink
Solution Approach 1:
Different portions of the conductive post have different width characteristics - the first portion has a narrower width for precision alignment, while the second portion has a wider width for robust electrical connection. This local quality differentiation allows the structure to optimize for both precision and manufacturability simultaneously.
3Manufacturing precision
If conductive post with varying width portions is used, then assembly and alignment precision is improved, but manufacturing process complexity increases
Solution Approach 1:
Instead of using a uniform width conductive post and adding alignment features, the invention inverts the approach by making the alignment-critical first portion narrower than the connection-critical second portion. This inverted width distribution naturally provides alignment precision without requiring additional complex alignment mechanisms.
Data Source
AI summary
At least some embodiments of the present disclosure relate to a substrate for packaging a semiconductor device. The substrate includes a first dielectric layer having a first surface, a first patterned conductive layer adjacent to the first surface of the first dielectric layer, and a conductive post. The first patterned conductive layer includes a first conductive pad and a second conductive pad. The conductive post is disposed on the first conductive pad. The conductive post includes a first portion and a second portion. The first portion and the second portion of the conductive post are exposed by the first dielectric layer. The first portion of the conductive post has a first width corresponding to a top line width of the first portion and the second portion of the conductive post has a width. The width of the second portion of the conductive post is greater than the first width of the first portion of the conductive post.