Dual Downset Leadframe Structure for Exposed Two-Sided Package Connections
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor device packages face challenges in accommodating sophisticated features while maintaining reliability, performance, and minimizing costs.
Innovation Solution
A semiconductor device with a dual downset leadframe configuration, where leads are bent in a specific manner to allow for efficient encapsulation and exposure of lead pads and distal portions, enabling cost-effective and reliable interconnects and connections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional leadframe configuration is used, then the semiconductor device package structure is simple, but the package interconnect reliability is reduced and product costs increase
Solution Approach 1:
The leadframe is divided into multiple segments with different downset configurations. Specifically, some leads have a first downset configuration while other leads have a second downset configuration, allowing each segment to serve different functional purposes (e.g., some for electrical connection, others for mechanical support or external component attachment), thereby improving overall package interconnect reliability without requiring complete redesign of the entire leadframe structure
Solution Approach 2:
Different portions of the leadframe are given different local properties through varying downset configurations. Leads requiring flexible connection to the semiconductor die have one downset configuration, while leads requiring stability for external component attachment have another configuration. This localized differentiation optimizes each lead's performance for its specific function, improving package interconnect reliability
2Adaptability or versatility
If sophisticated features are added to semiconductor devices, then device functionality is improved, but package configuration becomes susceptible to lower reliability and higher costs
Solution Approach 1:
The dual downset leadframe configuration serves multiple functions: it provides electrical connection between the semiconductor die and external circuitry, offers mechanical support for the die, enables attachment of external components to lead pads, and allows for different packaging styles. This multi-functionality accommodates sophisticated device features while maintaining package configuration reliability through a unified, proven structure
3Reliability
If leads are configured for direct connection without dual downset, then manufacturing process is simpler, but encapsulation efficiency and connection reliability are reduced
Solution Approach 1:
The leadframe is pre-configured with dual downset configurations during manufacturing, creating predetermined connection points and pathways before the semiconductor die is mounted. This preliminary structuring of leads with specific downset configurations facilitates subsequent assembly steps, including die attachment and encapsulation, improving connection reliability while the standardized process keeps manufacturing complexity manageable
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A semiconductor device is provided. The semiconductor device includes a leadframe having a plurality of leads. A first lead of the plurality of leads has a lead pad formed between a distal portion and a proximal portion of the first lead. A semiconductor die includes a plurality of bond pads located at an active side. Each bond pad of the plurality is connected to a respective lead of the plurality of leads. An encapsulant encapsulates the semiconductor die and at least a portion of the leadframe. A distal portion of each lead is exposed through the encapsulant at a first major side. The lead pad is exposed through the encapsulant at a second major side opposite of the first major side.