Vertical Wire Loops for Scalable Semiconductor Heat Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices face challenges in efficiently removing heat generated by active components due to thermal barriers, particularly in leadframe-based packages and Ball Grid Array packages, where heat must traverse the semiconductor chip thickness and face polymer attach materials, leading to increased thermal resistance and reduced heat dissipation efficiency.
Innovation Solution
The implementation of thermally conductive wire loops made of copper or gold, connecting the active chip surface to a metal heat spreader, which are scalable with chip size and designed to enhance thermal flux, allowing direct heat extraction from hotspots and reducing thermal resistance by improving thermal conductivity and geometry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If heat is removed through the thickness of the semiconductor chip to the passive surface and then to the leadframe, then heat extraction is achieved, but thermal resistance increases and heat dissipation efficiency decreases
Solution Approach 1:
The patent introduces wire loops that extend vertically from the active surface of the chip to a heat spreader positioned above the chip, creating a new thermal conduction path in the vertical dimension. This allows heat to be extracted directly from the hot active surface rather than forcing it to travel through the chip thickness to the passive surface, thereby reducing thermal resistance and improving heat dissipation efficiency.
Solution Approach 2:
The wire loops act as intermediary thermal conductors between the active chip surface and the heat spreader. These loops provide a direct thermal bridge that bypasses the thermal barrier of the chip substrate and polymer attach materials, enabling more efficient heat transfer from the heat-generating active components to the cooling structure.
2Area of moving object
If the chip size increases, then device functionality improves, but thermal resistance increases and heat removal becomes more difficult
Solution Approach 1:
The patent divides the thermal management system into multiple independent wire loops distributed across the chip surface. Each wire loop serves as an independent thermal conduction path, allowing heat to be removed from multiple locations simultaneously. This segmentation approach enables the thermal management system to scale with chip size, as additional loops can be added to larger chips to maintain effective heat removal.
Solution Approach 2:
By introducing vertical wire loops that extend from the active surface to an overhead heat spreader, the patent creates a three-dimensional thermal management architecture. This vertical dimension allows for direct heat extraction from the active surface regardless of chip area, enabling large chips to maintain low thermal resistance by providing multiple short vertical thermal paths rather than relying on lateral heat spreading through the chip substrate.
3Ease of manufacture
If traditional leadframe-based packages are used, then device assembly is simplified, but thermal flux is reduced and heat extraction efficiency decreases
Solution Approach 1:
The patent repositions the heat spreader from the traditional planar configuration attached to the passive surface to a vertical configuration positioned above the active surface, connected by wire loops. This dimensional change creates direct vertical thermal pathways from the heat-generating active components to the heat spreader, dramatically increasing thermal flux while maintaining compatibility with standard leadframe-based package assembly processes.
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 significantly enhances thermal flux and reduces thermal resistance, enabling effective two-way heat extraction and scalable thermal management for semiconductor devices, particularly in leadframe-based and Ball Grid Array packages, improving device performance and reliability.
Implementation Method 1
One or more thermal conductors connect the sheet and the first surface; the more than one wire loops have a number scalable with the chip size. Each conductor consists of a wire loop (preferably copper) with both wire ends attached to a pad, the loop having a major diameter approximately normal to the first surface and the vertex in contact with the sheet.
Implementation Method 2
A metal sheet covers at least portions of the third surface and is preferably made of copper to operate as a heat spreader.
Implementation Method 3
A substrate (preferably a second metal sheet) covers at least portions of the fourth surface and is thermally conductively connected to the second surface.
Data Source
AI summary
A semiconductor device (100A) with plastic encapsulation compound (102) and metal sheets (103a and 104) on both surfaces, acting as heat spreaders. One or more thermal conductors (103a) of preferably uniform height connect one sheet (103b) and the chip surface (101a); the number of conductors is scalable with the chip size. Each conductor consists of an elongated wire loop (preferably copper) with the wire ends attached to a pad (105), preferably both ends to the same pad. The major loop diameter is approximately normal to the first surface and the loop vertex in contact with the sheet (103b). The substrate (104, preferably a second metal sheet) covers at least portions of the second package surface and is thermally conductively connected to the chip.