Light Emitting Device Sealing Resin Wetting Control via Metal Oxide Film
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In light emitting devices, the sealing resin composition tends to exhibit unintended wetting and spreading on substrates with polar groups, leading to burr formation and scattering issues during subsequent processing steps.
Innovation Solution
A method involving the use of an addition curing silicone resin composition with an organopolysiloxane capable of crosslinking and an organic modified silicone oil that is unreactive with the organopolysiloxane, applied in conjunction with a metal oxide film on the substrate's side and upper surfaces to suppress wetting and spreading, ensuring the resin stays within the concave portion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a sealing resin composition is used on a substrate with polar groups, then the wettability between the sealing resin and substrate is enhanced, but the sealing resin causes unintended wetting and spreading to the upper surface of the concave portion
Solution Approach 1:
The patent applies different surface treatments to different regions: the bottom surface of the concave portion is treated to enhance wettability and adhesion, while the side surface is treated to reduce wettability and prevent spreading. This local differentiation of surface properties allows the sealing resin to adhere well at the bottom while being constrained within the concave portion.
Solution Approach 2:
The patent performs preliminary surface treatment of the substrate before applying the sealing resin composition. The bottom surface is activated with polar groups to enhance adhesion, while the side surface is treated to create a barrier against resin spreading. This preliminary preparation ensures the sealing resin behaves as desired during the sealing process.
2Reliability
If the sealing resin composition wets and spreads to unintended portions, then adhesion is improved, but burrs remain and scatter in subsequent process steps
Solution Approach 1:
The patent creates different surface energy characteristics in different locations: high surface energy on the bottom surface for strong adhesion, and low surface energy on the side surface to act as a barrier. This prevents the sealing resin from forming burrs on the side surfaces while maintaining excellent adhesion at the bonding interface.
Solution Approach 2:
The patent converts the potential harmful effect of reduced wettability on side surfaces into a beneficial barrier function. By making the side surfaces less wettable, the patent prevents resin spreading and burr formation, turning what could be poor adhesion into a useful containment mechanism.
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 approach effectively prevents unintended wetting and spreading of the sealing resin, reducing burr formation and scattering, thereby enhancing the production process and quality of light emitting devices.
Implementation Method 1
an organopolysiloxane containing a functional group capable of performing a crosslinking reaction
Implementation Method 2
forming a film comprising a metal oxide on the side surface of the concave portion and an upper surface of the substrate
Data Source
AI summary
A method for producing a light emitting device, including: integrally molding plural leads with a molded resin portion comprising a resin composition containing a thermosetting resin or a thermoplastic resin, so as to prepare a substrate having a concave portion having a side surface and a bottom surface; disposing a light emitting element on the bottom surface of the concave portion; forming a film including a metal oxide on the side surface of the concave portion and an upper surface of the substrate; disposing a sealing resin composition containing an addition curing silicone resin composition containing an organopolysiloxane containing a functional group capable of performing a crosslinking reaction and an aryl group in one molecule, and an organic modified silicone oil that is unreactive with the organopolysiloxane, in the concave portion; and curing the sealing resin composition to form a resin package.