Encapsulant dam standoff for shell-enclosed die assemblies

Abstract

Abstract An electronic device includes at least one chip connected to a circuit board. The chip includes a die and an encapsulant which is applied in a liquid phase and dries to a solid phase. A shell may be positioned over the chip and in some embodiments of the invention extends over the entire device. A dam is connected to the circuit board adjacent the die in at least one direction so as to restrain flow of the encapsulant toward the dam when the encapsulant is in the liquid phase. The dam may include an upper end at an elevation higher than the uppermost portion of the chip (which would usually be encapsulated), the dam acting as a standoff between the shell and the chip. The upper end of the dam may be constantly in contact with the shell or, alternatively, the upper end of the dam may be ordinarily not in contact with the shell, but comes into contact with the shell if the shell is compressed or flexed toward the chip. A single dam may surround the die (and chip structure after the encapsulant dries). Alternatively, a single dam may be adjacent to a die in less than all directions. Two or more chips may be adjacent to different sections or sides of a single dam.

Inventors

• 👤 Walter L. Moden
• 👤 John O. Jacobson

Bibliographic Details