Motorola Corporation

James F Landers

Thomas A Knappenberger

Frederick Y Cho

Ronald Dee Fuller

Theodore Harp, Iii

Russell J Elias

R Gordon Graham

Ken Brice-Heames

A moisture resistant conformal coating ( ) effectively protects high frequency circuits such as gallium arsenide MMICs from humidity and environmental contamination without the performance degradation inherent in conventionally applied conformal coatings. The conformal coating preferably comprises an organic polymer, such as silicone, applied to the MMIC die in a substantially uniform thickness of less than 0.002 inches, preferably of less than 0.0015 inches. This is accomplished by applying the organic polymer directly to the surface of the die ( ) in a mixture containing the solid organic polymer diluted with a low surface tension solvent, such as a volatile methyl siloxane.

High frequency gallium arsenide MMIC die coating method

A method for making a light weight circuit module includes steps of providing a substrate, drilling through holes in the substrate and plating the through holes with a metal. The substrate is a rigid planar substrate and having metallization on both sides. The method also includes steps of drilling through holes in the substrate and plating the through holes with a metal. The method also includes steps of preparing a patterned photoresist layer on at least one of the two sides, etching the metallization on the at least one side in accordance with the patterned photoresist layer, drilling support holes, filling the support holes with a material chemically distinct from the substrate, stripping the patterned photoresist layer from the at least one side and chemically removing the substrate from the metallization.

Method for manufacturing a light weight circuit module

A microwave absorbing ablating material is used as the ablative covering between the transmitting and receiving antennas while a standard ablating material, allowing the transmission of signals, is placed about the antennas. This allows signals to be transmitted from and received by the object covered by RF absorbing ablating material while preventing the transmission of signals transversely through the material. The RF absorbing, ablating material is made by combining an RF absorbing material with an ablating material in sufficient quantities to absorb and dissipate any signals that may be exposed to the ablative material.

RF absorbing ablating apparatus

A method for potting and encapsulating electronic circuits by providing a homogeneous mixture of uncured thermosetting resin and curing agent in a flowable powder form with a particle size in the range of approximately 60 mesh to 200 mesh and curable in a range of approximately 125.degree. F. to 212.degree. F., and hollow microspheres having a diameter in the range of approximately 5 microns to 300 microns, intermixing the resin-curing agent and microspheres in a ratio in the range of approximately 35 percent to 45 percent resin-curing agent to microspheres by weight, enclosing the electronic circuit with a form, pouring the homogeneous mixture in the form to surround one electronic circuit, and heating the mixture to the required temperature for curing.

Method for potting and encapsulating electronic circuits

A homogeneous mixture of uncured thermosetting resin and curing agent in a flowable powder form with a particle size in the range of approximately 60 mesh to 200 mesh and curable in a range of approximately 125.degree. F. to 212.degree. F., and hollow microspheres having a diameter in the range of approximately 5 microns to 300 microns, with the resin-curing agent and microspheres being intermixed in a ratio in the range of approximately 35 percent to 45 percent resin-curing agent to microspheres by weight.

Growing community of inventors

Tempe, AZ, United States of America

James F Landers