Design, Analysis and Validation of MCP Package for GaAs Monolithic Microwave Integrated Circuits Packaging

Abstract

This paper describes the design aspects of high reliable packages including package resonance, material selection, and feed-through design to match the die designer specifications. Design, simulation and thin film fabrication of 50Ω microstrip line on a 10 mil Al2O3 substrate suitable for MMIC assembly are also presented. Al2O3 substrate is taken because of lower transitional losses at the seal ring of the package, lower leakage and best suitable for hermiticity. Strip line design, study and the input-output transitions between two ports is analysed and optimized. Evidence of package self resonating mode study carried out theoretically and similar is simulated by using CST microwave studio. Package physical model analysis is carried out on a metal-ceramic package (MCP) which is suitable for embedding an amplifier of 20 dB gain and low power in c-band, 35 dB gain and low noise figure in s-band and 28 dB typical gain in x-band. Packaging effects in each case is analysed and optimised to meet the design requirements. With systematic ideas, the complete package modelling, characterization and MMICs packaging are carried out as per the reliability standards for space application. This package is sealed using the hermetic sealing technique to assure no leakage when subjected to the environmental test conditions like operating temperature test, active burn-in test for 240 h and steady-state life test for 1000 h to check MMIC behaviour under overstress conditions. Packaged module RF performances are noted at pre-subjected and post-subjected temperature conditions. Drifts are calculated at both temperature stages.