Semiconductor Device Lead Exposure for Size Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor devices with resin packages are limited in size reduction due to the larger size of the resin package relative to the semiconductor element, as the package covers the entire main lead, hindering miniaturization efforts.
Innovation Solution
The semiconductor device design includes a semiconductor element with a main lead exposed from the resin package, where the main lead has a full-thickness portion and an eaved portion, allowing the semiconductor element to not overlap the main lead, and wires are bonded using bumps to reduce the package size and enhance bonding strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the resin package covers the entire main lead, then the main lead is fully protected, but the package size becomes larger relative to the semiconductor element
Solution Approach 1:
The main lead is divided into two functional portions: a first portion that is covered by the resin package for protection, and a second portion that extends outward from the package. This segmentation allows the package to provide necessary protection while reducing the overall package size by not enclosing the entire lead structure.
Solution Approach 2:
The main lead extends in a direction outward from the resin package, creating a three-dimensional configuration where the lead protrudes from the package body. This dimensional arrangement allows the lead to be protected where needed while maintaining a compact package footprint.
2Reliability
If the semiconductor element overlaps the main lead, then better electrical connection is achieved, but the device cannot be miniaturized
Solution Approach 1:
The device structure separates the semiconductor element and main lead into non-overlapping spatial zones. The element is mounted on the package surface while the lead extends outward, eliminating the need for overlap while maintaining functional integrity through proper electrical connection at the bonding interface.
Solution Approach 2:
The main lead extends outward from the package in a direction perpendicular to the element mounting surface, creating a three-dimensional layout where the element and lead occupy different spatial zones. This eliminates the need for planar overlap while maintaining electrical connection through the bonding interface.
3Ease of manufacture
If wire bonding is used without bumps, then the bonding process is simpler, but bonding strength is insufficient
Solution Approach 1:
Bumps are introduced as intermediary structures on the electrode surfaces to enhance wire bonding. These bumps provide protruding contact points that increase the bonding area and mechanical interlocking between the wire and electrode, thereby strengthening the bond without complicating the overall wire bonding process.
Data Source
AI summary
The semiconductor device includes a semiconductor element, a main lead and a resin package. The semiconductor element includes an obverse surface and a reverse surface spaced apart from each other in a thickness direction. The main lead supports the semiconductor element via the reverse surface of the semiconductor element. The resin package covers the entirety of the semiconductor element. The resin package covers the main lead in such a manner that a part of the main lead is exposed from the resin package. The semiconductor element includes a part that does not overlap the main lead as viewed in the thickness direction.