Semiconductor Package Capacitive Coupling Bonding Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor packages using proximity communication face challenges with weak bonding strength between chips, leading to easy separation during mounting, which affects yield and reliability.
Innovation Solution
A semiconductor package design featuring first and second layer chips with signal coupling pads and metal bumps, where the second layer chip is capacitively coupled to the first layer chip, and encapsulated in a package body to increase bonding strength, along with a method involving a carrier, release tape, and metal bumps for assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If proximity communication is implemented using capacitive coupling between face-to-face pads on two chips, then input/output pad density is increased (about 100 times greater than traditional wire-bonding), but bonding strength between chips becomes weak causing easy separation during mounting
Solution Approach 1:
The invention divides the bonding interface into two distinct types: traditional strong mechanical bonding using metal bumps for structural support, and capacitive coupling pads for signal transmission. This segmentation allows each interface to fulfill its primary function - metal bumps provide bonding strength while capacitive pads enable proximity communication without compromising mechanical integrity
Solution Approach 2:
The invention introduces metal bumps as intermediary elements between the two chips. These metal bumps serve as the primary bonding mechanism that mechanically and electrically connects the chips, while the capacitive coupling pads operate separately for signal transmission, thus the metal bumps mediate the mechanical bonding function that was previously compromised by the proximity communication structure
2Reliability
If two chips are placed face-to-face with extreme accuracy for proximity communication, then capacitive coupling is achieved for communication, but the weak bonding strength causes easy separation during mounting affecting yield
Solution Approach 1:
The invention segments the functional requirements into two independent systems: a mechanical bonding system using metal bumps for structural integrity and mounting stability, and a capacitive coupling system for proximity communication. This segmentation ensures that the communication function does not compromise mechanical stability, thereby maintaining high yield during mounting processes
Solution Approach 2:
The invention changes the bonding mechanism parameter from relying solely on capacitive pad contact to using traditional metal bump bonding. This parameter change restores mechanical strength and bonding reliability to levels suitable for high-yield manufacturing, while preserving the capacitive coupling capability for communication through proper pad design and positioning
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 increased bonding strength between chips enhances the yield of the semiconductor package by stabilizing the connection during mounting and operation.
Implementation Method 1
The second signal coupling pads are disposed adjacent to the second active surface, and capacitively coupled to the first signal coupling pads of the first layer chip, so as to provide proximity communication between the first layer chip and the second layer chip.
Data Source
AI summary
The present invention relates to a semiconductor package having at least one first layer chip, a plurality of first metal bumps, at least one second layer chip and a package body. The first layer chip includes a first active surface upon which the first metal bumps are disposed and a plurality of first signal coupling pads disposed adjacent to the first active surface. The second layer chip is electrically connected to the first layer chip, and includes a second active surface that faces the first active surface and a plurality of second signal coupling pads. The second signal coupling pads are capacitively coupled to the first signal coupling pads so as to provide proximity communication between the first layer chip and the second layer chip. The package body encapsulates the first layer chip, the first metal bumps, and the second layer chip, and the first metal bumps are partially exposed.