Dow Corning Cookie Policy

We use cookies to enhance your experience with Dow Corning. Learn how cookies are used on this website and view our privacy statement.

By continuing to browse this site, you agree and consent for cookies to be used.

Continue
Silicones from Dow Corning
Log In | Profile/Preferences | Customer Support | Contact Us      Global (English). Change
Search
Go
Products             Technical Library             Premier Services             About Dow Corning             Careers
Electronics Products
Tutorials
Applications
Electronics Solutions
Product Resources
Technical Resources

LED Materials


<  1  2  3  4  5  6  >
Silicones Can Meet Needs for Performance and Reliability

In a wide variety of electronic devices, silicones have a long demonstrated history of providing useful properties such as clarity, stability, stress relief, processability and heat dissipation.

Optical clarity and lumen maintenance

Silicones have some of the highest clarity (transmission) values of any polymeric based materials. Light that is produced by the LED is transmitted efficiently with little absorbance within the silicone material. Silicones have the capacity to provide a wide range of refractive index (RI) values, from 1.40 to 1.58. By closer matching of the refractive index of the silicone to that of the substrate, interfacial losses can be minimized. The combination of clarity and refractive index of silicones can lead to increased light output and improved lumen maintenance. Silicone elastomers and resins can also be precisely molded into lenses to help focus and direct light output, again contributing to brightness within the targeted area of light distribution.

 

LED silicone applications

Optical Stability and Stress Relief

Another strong advantage of silicones is their thermal and photo stability in a variety of harsh environments. These features minimize the risk of yellowing or changes in physical properties during device fabrication and use. Their use also products provides thermal cycling reliability for protecting LEDs.

And because of the special materials used to fabricate these devices, many components in the package assemblies including the LED chips and their wirebonds can be sensitive to stress damage. Silicones have a soft, stress relieving nature that can cushion these devices from outside stress. Stability and the stress-relieving nature of silicones can significantly contribute to thermal cycling reliability and long lifetimes for the packaged LEDs.  

 

LED Encapsulant

Processability 

Many of today’s packaging and surface mount assembly processes for electronic and optical assemblies use lead-free solders, requiring high temperatures for reflow. The thermal stability of silicones helps them to survive these processes. And for the finished package, silicones have very low moisture absorption values. This means they can meet various levels of reliability requirements for subsequent processing operations with minimal handling concerns.

 

LED material processing

Heat Dissipation

And finally, an undesirable by-product of today’s HBLEDs is excessive heat generation.  In order to increase lumen output, devices are being designed for continuous operation at 165C and higher junction temperatures.  Silicone thermal management materials are well known today in high performance IC applications such as CPUs in flip-chip packages with heater spreaders and heat sinks. A variety of product forms such as adhesives, gels, phase-change pads and simple greases offer an array of options to address thermal management issues.

 

Silicone thermal dissipation

So, there are a wide variety of reasons to use silicones in the packaging of high brightness LEDs and, in many situations, they are becoming the material of choice for evolving LED applications.

<  1  2  3  4  5  6  >

 
  1. High Brightness LED Tutorial - Overview


  2. Uses of Silicones for LED Applications


  3. Silicones Can Meet Needs for Performance and Reliability


  4. Inherent Advantages of Silicones


  5. Applications for Silicone in LED's


  6. Tell Us What You Need


Media Center    |    REACH    |    Site Map    |    Other Dow Corning Websites
Using this website means you understand our Privacy Statement and agree to our Terms & Conditions.
©2000 - 2017 Dow Corning Corporation. All rights reserved. Dow Corning is a registered trademark of Dow Corning Corporation, a wholly owned subsidiary of The Dow Chemical Company.
The Corning portion of the Dow Corning trademark is a trademark of Corning Incorporated, used under license. XIAMETER is a registered trademark of Dow Corning Corporation. We help you invent the future is a trademark of Dow Corning Corporation.®™Trademark of The Dow Chemical Company ("Dow") or an affiliated company of Dow.
Dow Corning complies with the California Transparency in Supply Chains Act.