Semiconductor Package Insulation Layer for Bond Wire EMI Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge is to maintain or reduce the Z-height of semiconductor packages while preventing shorts between the bond wire and the EMI layer, which is complicated by the need for a wire clearance that increases manufacturing costs and complexity.
Innovation Solution
An insulation layer is provided between the molding compound and the EMI layer to cover exposed portions of the bond wire, allowing for a reduced Z-height and enabling the use of a thicker substrate without increasing the substrate thickness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wire clearance is increased to prevent shorts between bond wire and EMI layer, then reliability is improved, but Z-height increases
Solution Approach 1:
An insulation layer is introduced as an intermediary component between the bond wire and the EMI layer. This insulation layer provides the necessary electrical isolation to prevent shorts while allowing the bond wire to extend closer to the EMI layer, thereby reducing the required wire clearance and lowering the overall Z-height of the semiconductor package.
2Length of moving object
If substrate thickness is reduced to maintain Z-height with wire clearance, then Z-height is maintained, but manufacturing complexity and cost increase
Solution Approach 1:
The insulation layer serves as a mediator that allows the use of thicker substrates without increasing the overall Z-height. By providing electrical isolation, the insulation layer enables the bond wire to be positioned closer to the EMI layer, which compensates for the additional substrate thickness and maintains the desired package height.
Solution Approach 2:
The wire clearance requirement is segmented into two separate functions: electrical isolation (performed by the insulation layer) and spatial clearance (reduced by the insulation layer's presence). This segmentation allows the substrate thickness to be increased for manufacturing robustness while the insulation layer compensates for the increased height.
3Length of moving object
If wire clearance is set to minimum distance, then Z-height is reduced, but risk of shorts increases due to manufacturing variations
Solution Approach 1:
The insulation layer acts as a reliable intermediary that provides consistent electrical isolation regardless of manufacturing variations. By placing the insulation layer between the bond wire and EMI layer, the design achieves both minimum wire clearance for Z-height reduction and enhanced reliability through the insulation layer's protective function.
Data Source
AI summary
A semiconductor package includes an insulation layer provided between a molding compound and an electromagnetic interface (EMI) layer. The insulation layer covers an exposed portion of a bond wire that extends beyond a top surface of the molding compound due to a Z-height reduction of the molding compound. The insulation layer prevents a short from occurring between the bond wire and the EMI layer.