|
Encapsulation Materials — Tutorial
Silicon-based encapsulants are a new player in the microelectronics industry. Yet they are an integral part of the µ-BGA design.
Encapsulation materials are used to absorb the coefficients of thermal expansion mismatch found between the solder balls, the die and the printed wiring board. This property allows the parts to show the highest level of reliability.
Not all silicones are acceptable for use in these applications. A tremendous amount of time has been spent in the development and testing of silicone products to meet the needs of this application. To ensure trouble-free use with our materials, comprehensive quality controls must be put in place.
Adhering to the following recommendations and rules of thumb will give the user the best opportunity to successfully use Dow Corning® Chip Scale Encapsulants. These points are discussed in greater detail in this manual:
1. Project Review
• Once Dow Corning materials have been sampled, the contact points with the customer are clear and understood.
2. Product Quality
• The material supplied cures properly and is in its stated shelf life.
• Frozen material is allowed time to reach room temperature before using.
3. Package Materials Compatibility
• The package materials are tested in contact with the encapsulant for compatibility.
• Control limits are set on the other materials in the package to understand how the interaction with Dow Corning materials affects the reliability.
Specific product data sheets are available from your local Dow Corning Field Specialist in Europe and Asia, or from Dow Corning Customer Service (in the U.S. at 1-800-248-2481).
This guide is intended as a tool for understanding silicone encapsulants for microelectronics. Because setups vary, evaluation is always the recommended method of choosing a material.
|
Change
