Semiconductor Package Half-Bridge Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor packages increase overall resistance and inductance, causing undesirable effects like ringing, and require large heatsinks due to heat generation, which complicates package size and thermal management.
Innovation Solution
A semiconductor package design featuring thermally conductive circuit boards with interconnected power MOSFETs forming half-bridge circuits, using conductive tracks and pads on circuit boards to eliminate wirebonds and enable double-sided cooling with smaller heatsinks, and incorporating rectangular MOSFETs for improved thermal performance and switching speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional wirebond connections are used to interconnect semiconductor components, then electrical connectivity is achieved, but package resistance and inductance increase causing ringing
Solution Approach 1:
The patent removes wirebonds from the package structure entirely, replacing them with direct PCB trace connections. This extraction of the problematic wirebond element eliminates the source of increased inductance and resistance that cause ringing, while maintaining electrical connectivity through alternative means (PCB traces).
Solution Approach 2:
The patent substitutes the mechanical wirebond connection system with an electrical trace-based connection system on the PCB. This replacement eliminates the mechanical wirebonding process and its associated parasitic inductance and resistance, using instead conductive traces that provide lower impedance paths for electrical signals.
2Temperature
If large heatsinks are used to dissipate heat from power MOSFETs, then thermal management is improved, but package size increases
Solution Approach 1:
The patent merges the heatsink function directly with the PCB structure by making the PCB itself thermally conductive. This consolidation eliminates the need for separate, large external heatsinks, as the PCB serves dual purposes: electrical connectivity and thermal management. The thermal vias and conductive layers in the PCB create integrated heat dissipation paths.
Solution Approach 2:
The patent transitions from single-sided heat dissipation to double-sided heat dissipation by implementing thermal management on both sides of the PCB. Thermal vias conduct heat from the component side through the PCB to the opposite side, where additional copper layers and surface area provide enhanced heat dissipation, effectively utilizing both dimensions of the PCB structure.
3Ease of manufacture
If square MOSFETs are used in the package, then manufacturing is simplified, but thermal performance and switching speed are limited
Solution Approach 1:
The patent applies different geometric configurations to MOSFETs based on their specific functional requirements. Power MOSFETs are arranged in rectangular orientations optimized for current flow and thermal dissipation, while other components maintain standard configurations. This localized optimization of component geometry improves thermal performance and switching speed without requiring complete redesign of all components.
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 design reduces package size by allowing double-sided cooling with smaller heatsinks, minimizes adverse thermal characteristics, and enhances switching speed while maximizing solderable area for improved thermal performance.
Implementation Method 1
thermally conductive circuit boards with interconnected power MOSFETs forming half-bridge circuits, using conductive tracks and pads on circuit boards to eliminate wirebonds and enable double-sided cooling with smaller heatsinks
Data Source
AI summary
A multi-chip semiconductor package that includes two power semiconductor devices arranged in a half-bridge configuration between two opposing circuit boards.