Die Bump Ground Webbing for Crosstalk Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for an inexpensive and high-throughput process in semiconductor device packaging that achieves high yield and mechanical stability, while providing stable and clean power, ground, and high-frequency data signal transmission between IC chips and their packaging components, with existing solutions struggling to reduce crosstalk and improve copper density.
Innovation Solution
The implementation of a first-level die bump ground webbing structure using conductive material that surrounds data signal contacts, reducing bump field crosstalk and signal type cluster-to-cluster crosstalk by forming a conductive ground webbing layer connected to upper grounding contacts, thereby enhancing power delivery and data signal transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional packaging structures are used, then manufacturing cost is low and process is simple, but crosstalk between signals is high and frequency transmission is limited
Solution Approach 1:
The package structure is segmented into multiple functional layers including signal layer, ground webbing layer, and power layer. The ground webbing is divided into multiple isolated segments that surround individual data signal contacts, creating distinct isolation zones for each signal path. This segmentation reduces crosstalk between adjacent signals while maintaining manageable structural complexity.
Solution Approach 2:
The ground webbing structure extends vertically between the signal layer and the substrate, creating a three-dimensional shielding configuration. This vertical dimension adds electromagnetic shielding capability without significantly increasing the planar footprint, thereby improving signal transmission quality without proportionally increasing package area.
2Speed
If ground webbing structure is added to reduce crosstalk, then signal transmission frequency increases, but manufacturing process becomes more complex
Solution Approach 1:
The ground webbing structure is integrated with the existing substrate and signal contact structures. The webbing is formed as part of the same fabrication process that creates the ground contacts, merging multiple functions into a single structural element. This integration reduces the number of discrete manufacturing steps while achieving superior signal transmission performance.
Solution Approach 2:
The ground webbing acts as an intermediary structure between the data signal contacts and the ground contacts. It provides a controlled impedance path that mediates the electromagnetic field distribution, enabling high-frequency signal transmission while maintaining a relatively simple manufacturing process through standard PCB fabrication techniques.
3Reliability
If copper density is increased to improve power delivery, then power stability improves, but manufacturing precision requirements increase
Solution Approach 1:
The ground webbing structure concentrates copper density locally around each data signal contact where it is most needed for electromagnetic shielding and impedance control. Rather than uniformly increasing copper density throughout the entire package, the enhanced copper concentration is applied selectively at critical signal interfaces, improving power delivery stability while maintaining reasonable manufacturing precision requirements.
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 increases the frequency of data signal transmission up to 25 GT/s, improves copper density, and reduces crosstalk from 50 MHz to over 40 GHz, providing better power and signal stability through reduced impedance in the package.
Implementation Method 1
a first level die bump ground webbing structure that reduces bump field crosstalk, signal type cluster-to-cluster crosstalk and in-cluster signal type crosstalk by surrounding each of the upper transmit and receive data signal contacts
Implementation Method 2
conductive material extending between all of the upper power contacts, a layer of conductive material extending between all of the upper ground contacts, and a layer of conductive material extending between all of the upper data signal contacts
Data Source
AI summary
A ground isolation webbing structure package includes a top level with an upper interconnect layer having upper ground contacts, upper data signal contacts, and a conductive material upper ground webbing structure that is connected to the upper ground contacts and surrounds the upper data signal contacts. The upper contacts may be formed over and connected to via contacts or traces of a lower layer of the same interconnect level. The via contacts of the lower layer may be connected to upper contacts of a second interconnect level which may also have such webbing. There may also be at least a third interconnect level having such webbing. The webbing structure electrically isolates and reduces cross talk between the signal contacts, thus providing higher frequency and more accurate data signal transfer between devices such as integrated circuit (IC) chips attached to a package.