PERIOD OF PERFORMANCE: March 2010 to May 2013
The Navy plans to use advanced and integrated electronics in future radar platforms as the means to achieve transformational capability. These plans will include the development of less expensive, more easily applied, more reliable, and more moisture proof conformal coatings for radar electronics. Of particular interest is the Atomic Layer Deposition (ALD) ceramic based coating that has the potential of providing hermeticity to these electronics. Significant savings are expected from avoidance of the heavy, bulky, hermetic ceramic packaging currently used for this application, by coating the Monolithic Microwave Integrated Circuit (MMIC) chips before packaging or by coating the completed electronic assembly using these ALD-based coatings.
The objective of this project was to demonstrate, evaluate and test the capability and reliability of an Advanced Missile Defense Radar (AMDR) T/R module designed with ALD coated MMICs in QFN packages along with the board level coatings, and the functional performance and reliability of Ground/Air Task Oriented Radar (G/ATOR) T/R modules. By using ALD conformal coating at either the chip or completed module level (instead of the currently used hermetic ceramic packaging), an immediate reduction in the cost of all electronic hardware having conformal coatings on Navy weapons systems, ships, aircraft, and communications systems can be realized.
Cost reductions for the Marine Corps Ground/Air Task Oriented Radar (G/ATOR), and the Air and Missile Defense Radar (AMDR) for DDG 51 will occur as a result of this project. The AMDR T/R modules use costly ceramic packages with hermetic seals. The strategy was to reduce the labor and material costs of the system by utilizing plastic-based packaging, with equivalent performance of the existing hermetic packaging. Combining ALD coatings with the plastic packaging technology being developed under Navy ManTech project S2317 (Next Generation VSR Solid State LRU) is expected to lead to a 40 percent cost savings for each T/R module. The G/ATOR T/R module is currently packaged using low temperature co-fired ceramic (LTCC) with gold conductors, whose cost has impacted affordability. An ALD coating provides an environmental barrier and potentially enables the use of non-hermetic packaging for significant module cost reduction. Implementing High Temperature Cofired Ceramic (HTCC) packaging with ALD coating on the G/ATOR T/R module is projected to reduce packaging cost by 32 percent, enabling substantial cost savings at the G/ATOR system level.
This ALD Conformal Coatings effort helped develop the ALD processes and qualification methods for use in low cost plastic packaging and substrate technology for operation in a military environment. The ALD-coated T/R module performance is being validated through testing. Follow-on efforts will incorporate these reduced cost T/R modules into the AMDR system for test and qualification on the DDG 51. This project also developed manufacturing processes designed to result in a low cost T/R module for the front end of the U.S. Marine Corps Ground/Air Task Oriented Radar (G/ATOR) system. The project demonstrated that lower cost packaging can replace high cost gold, and assure component hermeticity and stable performance through the application of ALD conformal coatings in HTCC packages. A follow on Transition Program to integrate these processes into the G/ATOR system is planned, which will provide a T/R Module ready for Low Rate Initial Production (LRIP).