A microwave monolithic integrated circuit (MMIC) assembly and related
method are disclosed. A dielectric substrate has a surface on which radio
frequency circuits and microstrip lines are formed. At least one MMIC chip
opening is dimensioned for receiving therethrough a MMIC chip. A metallic
carrier is mismatched as to coefficient of thermal expansion to the
dielectric substrate and includes a component surface adhesively secured
to the dielectric substrate on the surface opposing the radio frequency
circuits and microstrip lines. At least one raised pedestal is on the
component surface that is positioned at the MMIC chip opening. A MMIC chip
is secured on the pedestal and extends through the MMIC chip opening for
connection to the radio frequency circuits and microstrip lines. Stress
relief portions are formed in the metallic carrier that segment the
carrier into subcarriers and provide stress relief during expansion and
contraction created by temperature changes.
