Extended Structure for Opening Formation in Semiconductor Encapsulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing encapsulation methods for packaged devices, such as semiconductor dies, often require complex and costly processes to create openings in the encapsulant for sensor regions or other exposed surfaces, which can be inefficient and device-specific.
Innovation Solution
Incorporating an extended structure on the leadframe or as a separate component that defines an area free of encapsulant during the encapsulation process, using a flat surfaced mold press to prevent encapsulant from covering sensitive regions, such as sensor areas, thereby simplifying and economizing the encapsulation process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If film assisted molding techniques or non-planar mold structures are used to form openings in the encapsulant, then the sensor regions can be exposed, but the manufacturing process becomes complex and costly
Solution Approach 1:
An opening formation structure is integrated into the mold press that creates the opening in the encapsulant during the encapsulation process itself, rather than requiring subsequent separate operations. The structure is positioned to define the opening space before encapsulation occurs, and the encapsulant is then molded around it, automatically forming the opening as the encapsulant cures.
Solution Approach 2:
A release film is placed over the opening formation structure during encapsulation to prevent encapsulant from adhering to the structure. After curing, the release film is removed, and the opening formation structure is subsequently removed, leaving a clean opening in the encapsulant. This intermediary approach simplifies the removal process and prevents defects.
2Manufacturing precision
If specialized non-planar mold structures are used to create openings, then sensor surfaces can be exposed, but manufacturing cost increases
Solution Approach 1:
The opening formation structure is designed as a universal component that can be integrated into standard planar mold presses. The same mold press structure can be used for different devices by changing only the opening formation structure, making it adaptable to various sensor types and opening configurations without requiring specialized non-planar molds for each application.
Solution Approach 2:
The opening formation structure pre-defines the exact location and dimensions of the opening before encapsulation begins. This preliminary positioning ensures accurate sensor region exposure while using simple, cost-effective planar mold structures rather than expensive customized non-planar molds.
3Ease of manufacture
If the encapsulation process is simplified using planar mold structures, then manufacturing cost decreases, but forming precise openings becomes difficult
Solution Approach 1:
The opening formation structure serves multiple functions simultaneously: it defines the opening space, supports the release film, and guides the encapsulant flow during molding. The structure is designed to work with the planar mold press geometry, allowing the simple mold structure to achieve precise opening formation through clever structural design rather than complex mold geometry.
Solution Approach 2:
The release film acts as an intermediary between the planar mold structure and the encapsulant, enabling precise opening formation. The film conforms to the opening formation structure during curing, ensuring accurate opening dimensions, and is easily removed afterward without damaging the encapsulant or requiring complex mold features.
Data Source
AI summary
A packaged device includes an extended structure located at a major side of the packaged device. The extended structure defines an outer area that includes encapsulated material on the major side and an inner area where there is a lack of encapsulant over a portion of the device at the major side. The extended structure prevents encapsulant from getting into the inner area during the encapsulating process.