Monolithic Conductive Column Structure for Underfill-Free Die Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor die assemblies face issues with conductive columns being under- or overfilled, leading to ineffective bonding between dies due to concave recesses or convex protrusions, which can result in poor electrical connections and die separation, exacerbated by stress from cooling or solidification processes.
Innovation Solution
The implementation of monolithic conductive columns that extend through multiple semiconductor dies, eliminating the need for additional conductive material between dies by forming a single elongated piece of conductive material in a single manufacturing step, thereby ensuring effective electrical communication and distributing stress evenly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional conductive columns are used in semiconductor dies, then electrical interconnection between dies is achieved, but underfill or overfill occurs leading to concave recesses or convex protrusions that cause ineffective bonding and die separation
Solution Approach 1:
The patent merges multiple separate conductive column formation operations into a single monolithic conductive column structure that extends continuously through multiple dies. This is achieved by forming a single elongated piece of conductive material that spans across die interfaces, eliminating the need for separate fill operations at each die interface and thereby preventing underfill/overfill issues.
Solution Approach 2:
The patent segments the conductive column formation process by creating distinct regions (first conductive region, second conductive region) within the monolithic structure that can be formed at different times or with different materials, while maintaining continuous electrical connection. This allows precise control over each region's properties without compromising the overall structural integrity.
2Volume of moving object
If bond line thickness is reduced to decrease assembly volume, then device compactness improves, but conductive columns become more prone to underfill or overfill
Solution Approach 1:
The patent performs preliminary actions by forming the monolithic conductive column structure to extend through predetermined openings in multiple dies before final bonding. The conductive material is deposited or formed to naturally fill the entire length of the column, ensuring proper fill without requiring precise control during the bonding process itself.
Solution Approach 2:
The patent changes the parameters of conductive column formation by using a single continuous formation process rather than multiple discrete fills. This involves controlling deposition parameters, temperature, and timing to ensure the conductive material fills the entire column length uniformly, adapting to the reduced bond line thickness without compromising fill accuracy.
3Adaptability or versatility
If multiple separate conductive columns are formed in different steps, then flexibility in material selection is improved, but process complexity and manufacturing steps increase
Solution Approach 1:
The patent creates a universal monolithic conductive column structure that can accommodate different material compositions in different regions. The single continuous structure serves multiple functions: providing electrical connection, mechanical support, and stress distribution, while allowing material versatility within a unified formation process.
Data Source
AI summary
A semiconductor device having monolithic conductive columns, and associated systems and methods, are disclosed herein. The semiconductor device can include a semiconductor substrate, a conductive pad, an opening, a non-conductive liner, and a plug of non-conductive material. The conductive pad may be at a surface of the semiconductor substrate. The opening may extend through the semiconductor substrate from the conductive pad to a second surface and define a side wall. The liner may coat the side wall and the plug may fill the opening. A second opening may be formed through the semiconductor device and the opening and a conductive material plated therein.