Selective Solder Seal Interface for IC Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for forming microchannel interfaces for integrated circuit cooling require complex and difficult-to-control processes, such as thick film lift-off and etch back, which complicate the deposition and removal of solder material in microchannel cooling systems.
Innovation Solution
A method involving the formation of a patterned plating seed layer on a substrate, using a seed layer and an etchant mask to create channels and subsequently plate solder, allowing for direct soldering of a heat exchanger with aligned cooling channels to a semiconductor structure without filling the channels with solder, thus enabling efficient heat dissipation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If selective solder deposition is performed after defining etched microchannel features, then solder can be deposited on the interface, but the process requires complicated lift-off of thick film or etch back of unwanted material
Solution Approach 1:
The patent applies preliminary action by forming the solder mask pattern and etch pattern simultaneously through a single lithography step, before any etching or soldering occurs. This preliminary patterning establishes both the microchannel geometry and the solder deposition regions in one go, eliminating the need for subsequent complex lift-off or etch back operations to remove excess solder material.
Solution Approach 2:
The patent merges the solder mask formation and etch pattern definition into a single lithographic patterning step. By combining these two separate processes that were traditionally performed sequentially into one simultaneous operation, the patent reduces process complexity while maintaining precise control over both microchannel formation and selective solder deposition.
2Manufacturing precision
If thick photolithography steps or hard to control etch steps are used to achieve selective solder deposition, then solder can be selectively placed, but the process becomes complex and difficult to control
Solution Approach 1:
The patent combines the solder mask pattern and etch pattern into a single lithographically defined pattern. This merged approach uses one photolithography step to create both patterns simultaneously, avoiding the need for thick photolithography steps or multiple sequential patterning operations, thereby simplifying manufacturing while maintaining precision.
Solution Approach 2:
The patent changes the parameter of pattern thickness by using a single lithographic layer that defines both solder and etch regions, rather than using thick multi-layer photolithography. This parameter change simplifies the manufacturing process while maintaining the ability to achieve selective solder placement through the integrated pattern design.
3Productivity
If channels are formed in the interface and then solder is deposited, then cooling channels can be created, but solder may fill the channels requiring complex removal processes
Solution Approach 1:
The patent performs preliminary action by defining the solder deposition regions before channel formation through simultaneous patterning. The lithographic pattern预先 establishes where solder should be placed at the channel openings, ensuring that subsequent soldering only occurs at the intended locations and does not fill the microchannels, eliminating the need for complex solder removal processes.
Solution Approach 2:
The patent uses the lithographically defined pattern as an intermediary that controls both the etching process and solder deposition. This intermediate pattern layer acts as a guide that directs the etchant to form channels while simultaneously marking the precise locations where solder should be applied, preventing solder from entering the channel interiors.
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 method simplifies the process of forming cooling channels and enhances thermal interface efficiency by allowing direct soldering and hermetic attachment of a heat exchanger to the semiconductor structure, maximizing cooling effectiveness while minimizing process complexity.
Implementation Method 1
using the patterned plating seed layer to form channels through the exposed portions of the substrate
Implementation Method 2
plating solder on the patterned plating seed layer
Implementation Method 3
the semiconductor structure is soldered to an opposite surface of the interface
Data Source
AI summary
A method for forming cooling channels in an interface for soldering to a semiconductor structure. The method includes: forming a metal seed layer on a surface of a substrate; patterning the metal seed layer into a patterned, plating seed layer covering portions of the substrate and exposing other portions of the substrate; using the patterned plating seed layer to form channels through the exposed portions of the substrate; and plating the patterned plating seed layer with solder. A heat exchanger having cooling channels therein is affixed to one surface of the interface and the semiconductor structure is soldered to an opposite surface of the interface. The cooling channels of the heat exchanger are aligned with the channels in the interface.