Semiconductor Package with Exposed Conductive Members for Thermal and EMI Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor packages face issues with electromagnetic shielding performance due to cavity resonance and poor heat radiation, primarily because of the size of the conductor shielding space and the use of low thermal conductivity materials, which lead to malfunctioning and heat retention.
Innovation Solution
The semiconductor package design includes a lead frame or package circuit board with integrated circuit chips, electrically conductive members, and wires sealed by a molded member, where the conductive members are exposed to enhance heat radiation from both the upper and bottom surfaces, and the effective size of the cavity is reduced to shift the cavity resonance frequency away from the operating band, improving electromagnetic shielding and heat dissipation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the distances between electrode pads, wires, and terminals are increased to suppress electrical coupling, then isolation among IC chips is improved, but the size of the semiconductor package is increased
Solution Approach 1:
The patent introduces conductor posts as intermediary elements that extend from the IC chips through the molded member to the conductor shielding. These posts provide both electrical connection and physical support, enabling closer spacing of IC chips while maintaining isolation through the shielding effect of the conductor posts and external shielding structure.
Solution Approach 2:
The patent implements a nested structure where IC chips are mounted on a die pad, which is mounted on a lead frame, which is then enclosed by a molded member with conductor shielding. This nested arrangement allows compact integration of multiple functional layers, reducing the overall package size while maintaining proper isolation and connection.
2Object-affected harmful factors
If conductor shielding is added to suppress external electromagnetic interference, then electromagnetic shielding performance is improved, but cavity resonance occurs that degrades isolation among IC chips
Solution Approach 1:
The conductor posts serve as intermediaries that connect the IC chips to the conductor shielding while breaking up the cavity space. These posts act as electromagnetic barriers that prevent resonance within the molded member, converting the continuous cavity into smaller segmented regions that do not support resonance at operating frequencies.
Solution Approach 2:
The patent changes the electromagnetic parameters of the package by introducing conductor posts with specific dimensions and positions. This modifies the cavity resonance characteristics, shifting resonance frequencies away from the operating band of the IC chips. The posts alter the effective permittivity and geometry of the enclosed space, suppressing harmful resonance.
3Reliability
If a resin molded member is used to seal the IC chips, then protection and sealing are improved, but heat radiation capability is degraded due to low thermal conductivity
Solution Approach 1:
The patent creates a composite thermal management structure by combining the resin molded member (for protection) with high thermal conductivity conductor posts and lead frame (for heat dissipation). This composite approach allows the package to simultaneously achieve environmental protection and effective heat radiation through multiple thermal pathways.
Solution Approach 2:
The conductor posts act as thermal intermediaries, conducting heat from the IC chip die pad through the molded member to the conductor shielding and external environment. These posts provide dedicated thermal conduction paths that bypass the low thermal conductivity of the resin, enabling efficient heat removal while maintaining the protective sealing function.
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 design effectively improves electromagnetic shielding performance by shifting the cavity resonance frequency to a higher range and enhances heat radiation capabilities, addressing both electromagnetic interference and thermal management issues.
Implementation Method 1
heat radiation from both the upper and bottom surfaces
Implementation Method 2
cavity resonance arises depending on the size of that space. If the frequency of the cavity resonance is in a vicinity of an operating band of the IC chips
Implementation Method 3
one or more electrically conductive members that are disposed on the die pad... enhances heat radiation
Data Source
AI summary
A semiconductor package includes a package main body. The package main body includes: a lead frame that includes first terminals and a die pad; two or more integrated circuit chips that are disposed on the die pad; one or more electrically conductive members that are disposed on the die pad; wires that connect the first terminals and the integrated circuit chips electrically; and a molded member that seals the lead frame, the integrated circuit chips, the electrically conductive member, and the wires. An upper surface, a bottom surface, and side surfaces of the package main body are formed by the molded member. The electrically conductive member is exposed through the upper surface of the package main body, and the die pad is exposed through the bottom surface of the package main body.