Protective Protrusion Layout for Pad-on-Element Semiconductors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor devices with pad-on-element structures face damage to circuit elements due to external stress, as the stress is not effectively distributed when applied to the electrode pad.
Innovation Solution
A semiconductor device design featuring a substrate with a target element, a protrusion, and an insulating film, where the electrode pad partially overlaps both, allowing impact loads to be distributed to the protrusion and the target element, reducing stress on the circuit element.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a pad-on-element structure is used to reduce chip size, then the area is reduced, but the circuit element becomes vulnerable to impact damage
Solution Approach 1:
The electrode pad is segmented into two functional zones: a first region directly overlapping the circuit element and a second region extending beyond the element. This segmentation allows the pad to simultaneously maintain compact area while distributing impact forces away from the vulnerable circuit element through the extended second region.
Solution Approach 2:
An insulating film is introduced as an intermediary layer between the electrode pad and the circuit element. This mediator layer has controlled mechanical properties that allow it to absorb and distribute impact forces, protecting the circuit element from direct stress while maintaining the pad-on-element structure's compact area.
2Stress or pressure
If surface asperities are formed on the pad to extend stress distribution area, then stress distribution is improved, but impact damage to the circuit element still occurs
Solution Approach 1:
The solution extends the pad structure from a two-dimensional surface modification (asperities) into the third dimension by creating a protrusion that extends beyond the element boundaries. This dimensional transition allows stress distribution to occur both laterally through asperities and vertically through the protrusion's extended region, effectively protecting the circuit element while maintaining compact area.
Solution Approach 2:
The electrode pad is divided into a first region for direct connection and a second protruding region for stress distribution. This segmentation enables the pad to simultaneously provide electrical connection and impact protection, resolving the contradiction between compact area and reliability.
Data Source
AI summary
A target element to be protected and a protrusion are arranged on a substrate. An insulating film arranged on the substrate covers the target element and at least a side surface of the protrusion. An electrode pad for external connection is arranged on the insulating film. The electrode pad at least partially overlaps the target element and the protrusion as seen in plan view. A maximum distance between the upper surface of the protrusion and the electrode pad in the height direction is shorter than a maximum distance between the upper surface of the target element and the electrode pad in the height direction.