Sorry, you need to enable JavaScript to visit this website.


Strategies for Wide Bandgap, Inexpensive Transistors for Controlling High-Efficiency Systems

The projects in ARPA-E's SWITCHES program, which is short for Strategies for Wide-Bandgap, Inexpensive Transistors for Controlling High-Efficiency Systems, are focused on developing next-generation power switching devices that could dramatically improve energy efficiency in a wide range of applications, including new lighting technologies, computer power supplies, industrial motor drives, and automobiles. SWITCHES projects aim to find innovative new wide-bandgap semiconductor materials, device architectures, and device fabrication processes that will enable increased switching frequency, enhanced temperature control, and reduced power losses, at substantially lower cost relative to today's solutions. More specifically, SWITCHES projects are advancing bulk gallium nitride (GaN) power semiconductor devices, the manufacture of silicon carbide (SiC) devices using a foundry model, and the design of synthetic diamond-based transistors. A number of SWITCHES projects are small businesses being funded through ARPA-E's Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) program.

For a detailed technical overview about this program, please click here.  

Arizona State University

Diamond Power Transistors Enabled by Phosphorus Doped Diamond

Arizona State University (ASU) will develop a process to produce low-cost, vertical, diamond semiconductor devices for use in high-power electronics. Diamond is an excellent conductor of electricity when boron or phosphorus is added-or doped-into its crystal structures. In fact, diamond can withstand much higher temperatures with higher performance levels than silicon, which is used in the majority of today's semiconductor devices. However, growing uniformly doped diamond crystals is difficult and expensive. ASU's innovative diamond-growing process could create greater doping uniformity, helping to significantly lower the cost of diamond semiconductor devices.

Avogy, Inc.

Vertical GaN Transistors on Bulk GaN Substrates

Avogy will develop a vertical transistor with a gallium nitride (GaN) semiconductor that is 30 times smaller than conventional silicon transistors but can conduct significantly more electricity. Avogy's GaN transistor will function effectively in high-power electronics because it can withstand higher electric fields and operate at higher temperatures than comparable silicon transistors. Avogy's vertical device architecture can also enable higher current devices. With such a small and efficient device, Avogy projects it will achieve functional cost parity with conventional silicon transistors within three years, while offering game-changing performance improvements.

Columbia University

Vertical GaN Power Transistors Using Controlled Spalling for Substrate Heterogeneity

Columbia University will create high-performance, low-cost, vertical gallium nitride (GaN) devices using a technique called spalling, which involves exfoliating a working circuit and transferring it to another material. Columbia and its project partners will spall and bond entire transistors from high-performance GaN wafers to lower cost silicon substrates. Substrates are thin wafers of semiconducting material needed to power devices like transistors and integrated circuits. GaN substrates operate much more efficiently than silicon substrates, particularly at high voltages, but the high cost of GaN is a barrier to its widespread use. The spalling technique developed by Columbia will allow GaN substrates to be reused, lowering their manufacturing cost.

Cornell University

PolarJFET - A Novel Vertical GaN Power Transistor Concept

Cornell University will develop an innovative, high-efficiency, gallium nitride (GaN) power switch. Cornell's design is significantly smaller and operates at much higher performance levels than conventional silicon power switches, making it ideal for use in a variety of power electronics applications. Cornell will also reuse expensive GaN materials and utilize conventional low-cost production methods to keep costs down.

Fairfield Crystal Technology, LLC

High-Quality, Low-Cost GaN Single Crystal Substrates for High-Power Devices

Fairfield Crystal Technology will develop a new technique to accelerate the growth of gallium nitride (GaN) single-crystal boules. A boule is a large crystal that is cut into wafers and polished to provide a surface, or substrate, suitable for fabricating a semiconductor device. Fairfield Crystal Technology's unique boule-growth technique will rapidly produce superior-quality GaN crystal boules-overcoming the quality and growth-rate barriers typically associated with conventional growth techniques, including the current state-of-the-art hydride vapor phase epitaxy technique, and helping to significantly reduce manufacturing costs.

HRL Laboratories, LLC

Low-Cost Gallium Nitride Vertical Transistor

HRL will develop a high-performance, low-cost, vertical gallium nitride (GaN) transistor that could displace the silicon transistor technologies used in most high-power switching applications today. GaN transistors can operate at higher temperatures, voltages, and currents than their silicon counterparts, but they are expensive to manufacture. HRL will combine innovations in semiconductor material growth, device fabrication, and circuit design to create its high-performance GaN vertical transistor at a competitive manufacturing cost.

iBeam Materials, Inc.

GaN LEDs on Flexible Metal Foils

iBeam Materials is developing a scalable manufacturing method to produce low-cost gallium nitride (GaN) LED devices for use in solid-state lighting. iBeam Materials uses an ion-beam crystal-aligning process to create single-crystal-like templates on arbitrary substrates thereby eliminating the need for small rigid single-crystal substrates. This process is inexpensive, high-output, and allows for large-area deposition in particular on flexible metal foils. In using flexible substrates, in contrast to rigid single-crystal wafers, the ion-aligning process also enables roll-to-roll (R2R) processing of crystalline films. R2R processing in turn simplifies manufacturing scale-up by reducing equipment footprint and associated labor costs By fabricating the LED directly on a metal substrate, one "pre-packages" the LED with the reflector and the heat sink built-in. This significantly reduces cost, simplifies packaging and allows a pick-and-place (P&P) technology to be replaced with printing of LEDs.

Kyma Technologies, Inc.

Transformational GaN Substrate Technology

Kyma will develop a cost-effective technique to grow high-quality gallium nitride (GaN) seeds into GaN crystal boules, which are used as the starting material for a number of semiconductor devices. Currently, growing boules from GaN seeds is a slow, expensive, and inconsistent process, so it yields expensive electronic devices of varying quality. Kyma will select the highest quality GaN seeds and use a proprietary hydride vapor phase epitaxy growth process to rapidly grow the seeds into boules while preserving the seed's structural quality and improving its purity.

Michigan State University

Diamond Diode and Transistor Devices

Michigan State University (MSU) will develop high-voltage diamond semiconductor devices for use in high-power electronics. Diamond is an excellent conductor of electricity when boron or phosphorus is added-or doped-into its crystal structures. It can also withstand much higher temperatures with higher performance levels than silicon, which is used in the majority of today's semiconductors. However, current techniques for growing doped diamond and depositing it on electronic devices are difficult and expensive. MSU is overcoming these challenges by using an innovative, low-cost, lattice-etching method on doped diamond surfaces, which will facilitate improved conductivity in diamond semiconductor devices.

MicroLink Devices

High-Power Vertical-Junction Field-Effect Transistors Fabricated on Low-Dislocation-Density GaN by Epitaxial Lift-Off

MicroLink Devices will engineer affordable, high-performance transistors for power conversion. Currently, high-performance power transistors are prohibitively expensive because they are grown on expensive gallium nitride (GaN) semiconductor wafers. In conventional manufacturing processes, this expensive wafer is permanently attached to the transistor, so the wafer can only be used once. MicroLink Devices will develop an innovative method to remove the transistor structure from the wafer without damaging any components, enabling wafer reuse and significantly reducing costs.

Monolith Semiconductor, Inc.

Advanced Manufacturing and Performance Enhancements for Reduced Cost Silicon Carbide MOSFETS

Monolith Semiconductor will utilize advanced device designs and existing low-cost, high-volume manufacturing processes to create high-performance silicon carbide (SiC) devices for power conversion. SiC devices provide much better performance and efficiency than their silicon counterparts, which are used in the majority of today's semiconductors. However, SiC devices cost significantly more. Monolith will develop a high-volume SiC production process that utilizes existing silicon manufacturing facilities to help drive down the cost of SiC devices.

SixPoint Materials, Inc.

GaN Homoepitaxial Wafers by Vapor Phase Epitaxy on Low-Cost, High-Quality Ammonothermal GaN Substrates

SixPoint Materials will create low-cost, high-quality vertical gallium nitride (GaN) substrates for use in high-power electronic devices. In its two-phase project, SixPoint Materials will first focus on developing a high-quality GaN substrate and then on expanding the substrate's size. Substrates are thin wafers of semiconducting material used to power devices like transistors and integrated circuits. SixPoint Materials will use a two-phase production approach that employs both hydride vapor phase epitaxy technology and ammonothermal growth techniques to create its high-quality, low-cost GaN substrates.

Soraa, Inc.

Large-Area, Low-Cost Bulk GaN Substrates for Power Electronics

Soraa will develop a cost-effective technique to manufacture high-quality, high-performance gallium nitride (GaN) crystal substrates that have fewer defects by several orders of magnitude than conventional GaN substrates and cost about 10 times less. Substrates are thin wafers of semiconducting material needed to power devices like transistors and integrated circuits. Most GaN-based electronics today suffer from very high defect levels and, in turn, reduced performance. In addition to reducing defects, Soraa will also develop methods capable of producing large-area GaN substrates-3 to 4 times larger in diameter than conventional GaN substrates-that can handle high-power switching applications.

University of California, Santa Barbara

Current Aperture Vertical Electron Transistor Device Architectures for Efficient Power Switching

The University of California, Santa Barbara (UCSB) will develop new vertical gallium nitride (GaN) semiconductor technologies that will significantly enhance the performance and reduce the cost of high-power electronics. UCSB will markedly reduce the size of its vertical GaN semiconductor devices compared to today's commercially available, lateral GaN-on-silicon-based devices. Despite their reduced size, UCSB's vertical GaN devices will exhibit improved performance and significantly lower power losses when switching and converting power than lateral GaN devices. UCSB will also simplify fabrication processes to keep costs down.

The ARPA-E model is unique in that the agency does not just provide teams funding. Throughout the lifetime of an ARPA-E award, ARPA-E Program Directors and Tech-to-Market Advisors also provide teams with expert advice through quarterly reviews and onsite visits. This hands-on approach helps ensure teams can meet ambitious milestones, target and tackle problems early on, and advance their technologies towards commercialization. Program Director Dr. Isik Kizilyalli explains the importance of this active project management approach in helping teams identify and overcome barriers. In this video, Energy Storage Systems (ESS) from the GRIDS program and Monolith Semiconductors from the SWITCHES program discuss how ARPA-E’s active project management approach helped them find solutions to technical challenges.

Subscribe to SWITCHES