Agency: National Aeronautics and Space Administration | Branch: | Program: SBIR | Phase: Phase II | Award Amount: 750.00K | Year: 2016
In this Phase II program we propose to develop a manufacturable production process to introduce backside contacts to MicroLink Devices? large-area, multi-junction epitaxial lift-off (ELO) solar cells. We will also develop new assembly processes to fabricate flexible Kapton sheets with backside contact ELO solar cells. This enables an important path for cost reduction using fully automated laydown and interconnect of solar panels. The new backside contact ELO solar cell technology has potential benefits for future NASA solar electric propulsion (SEP) programs using very large solar cell arrays. Backside contacts are used in the highest efficiency silicon solar cells manufactured by SunPower (>24% efficiency in production) but have never been successfully applied commercially to multi-junction solar cells. Benefits for large-area space solar cell include: higher device efficiency by reducing topside grid shadow and resistive losses, new approaches for panel assembly by placing contacts on backside of solar cell, and reduced arcing in high-voltage arrays by eliminating topside interconnects. The proposed technology builds on MicroLink Devices? low-cost, lightweight ELO solar cell technology and previous experience with backside contact solar cells for CPV applications.
Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase II | Award Amount: 755.00K | Year: 2016
MicroLink Devices in collaboration with University of Notre Dame will develop composite lightweight, high-efficiency, epitaxial lift-off (ELO) inverted metamorphic (IMM) triple junction solar cells ideally suited for retrofitting current generation UAVs and integration with next generation platforms in order to substantially increase mission duration beyond current battery only technologies. MicroLink will target composite ELO solar cells (CSC) with ultra high specific power (>3.0 kW/kg) and very high areal power density (>370 W/m2). ELO is a unique disruptive technology that affords an attractive cost reduction model through substrate reclaim whereby the substrate after solar cell functional layers have been removed can be repolished and used for another solar cells growth. This model allows the cost of the substrate to be spread over several solar cell growth runs.
Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 80.00K | Year: 2016
The objective of the proposed project is to develop a lightweight, robust, and modular system, capable of harvesting solar energy in areas with dense foliage cover in an effective manner. The system proposed will be able to reach a height of 100 feet above an average tropical forest canopy to deploy a solar array capable of generating 250 W under AM1.5G 1-sun illumination. In this proposal, MicroLink will evaluate and down select from two different deployment approaches. One will consist of a collapsible boom made of lightweight composite material that can extend to a forest canopy and a highly efficient solar array that can deploy at the target height. The other will consist of a ground based projectile launcher with a solar panel payload that will deploy once it reaches its peak height and then rests itself on top of the canopy. Both will feature a solar array with 1 m2 of active solar cell area, generating 250 W of power 24 VDC under AM1.5G 1-sun illumination.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 150.00K | Year: 2015
ABSTRACT:MicroLink Devices, in collaboration with Dr. Scott Messenger at the University of Maryland Baltimore County (UMBC), proposes to develop an ultra-high efficiency, radiation-hard, six-junction solar cell for application to Air Force space missions. The proposed technology will comprise lattice-matched subcells grown on InP and GaAs substrates that are mechanically attached in a monolithic structure to achieve an AM0 efficiency in excess of 40%. To render the solar cell cost-efficient, epitaxial lift-off (ELO) will be used to separate the epitaxial layers from the InP substrate, allowing it to be reused for multiple growth cycles. The thin epitaxial layers will be attached to the back of the GaAs substrate in the final device structure using an epoxy bonding process. Dr. Messenger, a pioneer in the field of radiation modeling, will perform realistic environment simulations for missions in GEO, MEO and LEO, and the solar cell structure will be optimized for performance in the relevant mission radiation environment.BENEFIT:A successful development program will result in an increase in the efficiency of our multi-junction solar cells. The expected absolute efficiency of the devices ultimately enabled by the proposed technology is at least 40%. The proposed high-efficiency solar cells will be an attractive replacement for existing Ge-based triple-junction solar cells in all applications in which these cells are used. A major potential application is high-efficiency solar cells for use in solar-powered spacecraft, which will meet the needs of NASA, the DoD, other Federal Agencies, and the private sector. Customers of the products would be the makers of solar arrays for spacecraft, including Boeing, Lockheed Martin, ATK, and Space Systems Loral. Other applications that would benefit from increased efficiency solar cells include high-altitude, long-endurance (HALE) solar-powered aircraft. These aircraft are attractive for remote surveillance applications in which the aircraft could remain on station for months or years. In order to increase the geographic area that the HALE aircraft can cover, it is essential that the efficiency of the solar cell be improved. The cells described in the proposal could be easily converted for use in HALE applications. Customers that could benefit from this cell technology include DARPA (Vulture aircraft), Airbus (manufacturer of the Zephyr UAV), and Facebook or Google (new players in the HALE market).
Agency: Department of Energy | Branch: ARPA-E | Program: SBIR | Phase: Phase II | Award Amount: 1.50M | Year: 2014
In this program, we will develop a breakthrough technology that will enable wafer-scale epitaxial lift-off (ELO) of GaN power device heterostructures from low-dislocation-density bulk GaN substrates. This technology will be used to provide a low-cost vertical junction field effect transistors (VJFETs) with high breakdown voltage (greater than 1,200 V) and high current capability (greater than 100 A). Despite the recent commercial success of GaN-based optical and electronic devices, the high dislocation density resulting from the use of mismatched substrates leads to fundamental performance, reliability, and thermal conductivity limitations in vertical power device applications. Bulk GaN substrates with low dislocation density (less than 10^5 cm-2) are under development in small diameters (1 inch - 2 inch) but at high cost. MicroLink is an industry leader in the commercialization of ELO and in the reuse of GaAs and InP substrates for multi-junction solar cells. MicroLink is also a leading producer of GaAs VJFETs and HBTs. The proposed principal investigator carried out pioneering work on photoelectrochemical wet etching of GaN materials. We will leverage this expertise to develop a new ELO-based layer transfer technology using reusable bulk GaN templates for epitaxial growth to enable high quality GaN materials at dramatically lower cost. We will demonstrate the viability of this technology using a novel vertical junction FET device, which leverages our experience in producing GaAs VJFETs. We have assembled a team of world-class partners with expertise on GaN epitaxial growth, bulk GaN substrates, modeling, power device design, and device testing.