SBIR-STTR Award

Nuvotronics will develop a robust wafer-level integration technology using our proprietary PolyStrata interposer to enable high-frequency interconnects and routing between two dis-similar substrates: silicon, SiGe, GaAs, GaN, InP wafers. The PolyStrata passives grown on the wafers will consist of high performance interconnects capable of aligning and soldering the two wafers using copper pillars to create a Ball Grid Array (BGA). Establishing novel wafer-to-wafer push fit technologies will demonstrate sub 5psec interconnection delay between technologies. With integration of low loss routing between the technologies, our proposed interposer can monolithically integrate passives such as high Q inductors, filters, resonators directly between the two wafers. The PS interposer offers an excellent structure to improve the CTE mismatch between wafers and enable thermal heat piping to direct the heat away from the different stack. In Ph I, Nuvotronics will demonstrate the integration of GaAs on Silicon using the PS interposer technology. The goal: to integrate a 1"x1" GaAs and Silicon die, demonstrating interface loss < 0.3dB and sub 5psec interconnection delay. The design will integrate CTE compensation structure to enable over 100C of temperature variation. Nuvotronics will design and optimize the interface between PolyStrata and silicon, and between GaAs and PolyStrata, to minimize stress and improve mm-wave RF performance. Next, Nuvotronics will fabricate a surrogate silicon and surrogate GaAs wafer with PolyStrata interface. A solder ball back-end process will be applied to both wafer technology and integration of solder balls. The 4" wafers will be diced in 1"x1" dies before being integrated. DC and RF measurements will demonstrate electrical performance. Preliminary temp. cycling will be performed to demonstrate reliability of the interface. In Ph II, Nuvotronics will demonstrate 4-inch wafer level integration and performance under temp. cycling.

Potential NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) Nuvotronics is committed to transitioning the proposed technology to NASA applications for future phased arrays and more integrated RF systems. Our involvement in 3 NASA IIP awards and 2 Phase IIE projects in combination with 2 additional prime contractor/government sponsored efforts for space borne instruments (totaling over $12M) will help reduce risk in transitioning the proposed technology to NASA space platforms.

Potential NON-NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) The technology developed can be leveraged in commercial phased array for the next generation 5G network. In this new mm-wave domain, the challenges of creating microwave circuits become exponentially harder. PolyStrata technology offers a revolutionary solution by compartmentalizing all of the microwave "challenges" into a single integrated component, placed on a standard printed circuit board.

Technology Taxonomy Mapping:
(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) Amplifiers/Repeaters/Translators Antennas Manufacturing Methods Microelectromechanical Systems (MEMS) and smaller Microfabrication (and smaller; see also Electronics; Mechanical Systems; Photonics)

Over the course of this program, Nuvotronics will develop of a robust wafer-level chip integration technology using our proprietary PolyStrata® process to enable sub-millimeter monolithic integrated chip (IC). This new process offers a disruptive wafer level packaging, capable of monolithically integrating dis-similar semiconductor substrates such as silicon, SiGe, GaAs, GaN and InP while reducing the interconnects losses and removing the need wirebonds. Using the 8” PolyStrata process on wafer, different chips (Low Noise Amplifiers, PAs, Mixers, switches) can be monolithically integrated and interconnected using copper microfabrication process to create a IC module. To demonstrate the performance of the new wafer level packaging approach, during the Phase II, Nuvotronics will leverage the new process to fabricate a complete W-band monolithic radiometer IC. The PolyStrata IC will be surface mountable using industry standard reflow process and will not require wirebonding, high accuracy placements or expensive RF circuit board. Nuvotronics aimed in this program a revolutionizing the way mm-wave circuit are fabricated by improving the interconnection performance up to 220 GHz and significantly reducing the packaging cost.

Potential NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) -NASA Goddard is looking at possible insertion of this technology in measurement instruments for radiometry in a CubeSat payload. Integration of MMICs at frequency above 60GHz requires challenging processes such accurate die placement and ultra-short wirebonds to ensure repeatable performance. -Mapping gas-tracing spectral lines to study Star formation in galactic molecular gas clouds.-Mapping low surface brightness emission, like large-scale structure, with existing millimeter-wave interferometers to enhanced with small focal plane arrays on each telescope that would increase the field of view. -Earth science remote sensing missions, such as the Cloud Precipitation Processes Mission (CaPPM)-Possible: Snow and Cold Land Processes (SCLP) mission



Potential NON-NASA Commercial Applications:
:
(Limit 1500 characters, approximately 150 words) The number of backhaul radios operating at E-band and even D-band are growing rapidly to provide a faster wireless network. Access Point-to-point and point to multi-point datalinks are expected to rapidly increase to fill the 5G network requirements and will require cost effective mm-wave hardware.

Technology Taxonomy Mapping:
(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) Aerogels Amplifiers/Repeaters/Translators Antennas Ceramics Manufacturing Methods Materials (Insulator, Semiconductor, Substrate) Microelectromechanical Systems (MEMS) and smaller Microfabrication (and smaller; see also Electronics; Mechanical Systems; Photonics) Nanomaterials Processing Methods