Multi-Layer Encapsulation for RF Transistor Amplifiers

The patent transitions from conventional two-dimensional packaging to a three-dimensional multi-layer encapsulation structure. The encapsulation includes multiple dielectric layers and conductive layers stacked vertically, with the RF transistor amplifier die mounted on a submount at the bottom layer. This vertical stacking enables integrated heat dissipation pathways through the layers and reduces input-output coupling by spatially separating connections in the third dimension, simultaneously addressing both heat management and signal integrity issues.

The patent introduces a submount as an intermediary component between the RF transistor amplifier die and the mounting surface. The submount serves as a mediator that provides both mechanical support for mounting and electrical isolation to reduce coupling between input and output connections. Additionally, the multi-layer dielectric and conductive structure acts as an intermediary field management system that controls electromagnetic fields to improve impedance matching efficiency while maintaining ease of manufacture.

The patent implements a multi-layer encapsulation structure where each layer serves multiple functions. The dielectric layers provide both mechanical encapsulation protection and serve as substrates for forming conductive circuits for impedance matching and harmonic termination. The conductive layers simultaneously provide electrical connections, RF shielding, and functional circuit elements. This multi-functionality allows the encapsulation to protect the die while integrating essential RF performance circuits, achieving both structural simplicity and functional versatility.