Kyma Technologies and Virginia Commonwealth University Demonstrate Benefits of Bulk GaN for LED and Transistor Applications

Kyma Technologies, Inc., a leading supplier of ultra-high purity crystalline gallium nitride (GaN) and aluminum nitride (AlN) materials and related products and services, today announced select results of its collaboration with Professor Hadis Morkoç of Virginia Commonwealth University (VCU).

Professor Morkoç is the Founders Professor of Electrical Engineering and Physics at VCU and is one of the world’s most prolific researchers involved in development of advanced electronic and optoelectronic compound semiconductor device technologies.  Internationally renowned for his work in advanced GaAs and InP device technologies, in recent years Professor Morkoç has focused on wide bandgap semiconductor materials like zinc oxide (ZnO) and GaN for novel device applications.

Kyma’s Chief Scientist Dr. Tanya Paskova is working closely with Professor Morkoç and his research group in two important device areas:  high-efficiency light-emitting diodes (LEDs) and high-frequency field effect transistors (FETs).  For both device types, performance and reliability benefits are expected when using Kyma’s low defect density GaN substrates.  Additional benefits can arise from selecting a particular substrate orientation.

The Kyma-VCU team has just begun to publish some of their results.

For LED applications, Kyma’s bulk m-plane GaN has the potential to provide higher internal quantum efficiencies (IQE) could translate to higher wall plug efficiency.  A VCU-led paper [Appl. Phys. Lett. 95, 121107 (2009)] entitled “Efficiency retention at high current injection levels in m-plane InGaN light emitting diodes,” appeared online on 22Sep09.  This paper shows that IQE values were consistently higher, by some 30%, for the m-plane LEDs than for reference c-plane LEDs having the same structure, e.g., 80% versus 60% at an injected steady-state carrier concentration of 1.2x1018 cm−3. With increasing current injection up to 2500 A/cm2, the maximum external quantum efficiency (EQE) was nearly retained in m-plane LEDs, whereas c-plane LEDs exhibited approximately 25% droop.

For high-frequency FET applications, the team is exploring a range of innovative (In,Ga,Al)N/GaN heterostructures.  Excellent performance, in terms of low leakage, high sheet charge and high carrier mobility, and very high frequency x gate length product (ft x lg), has been obtained for certain structures.  Detailed results will appear soon in several scientific publications.

Dr. Keith Evans, Kyma’s President and CEO commented, “It is a great pleasure to see the rapid progress that Professor Morkoç is able to make in validating the potential of our bulk GaN substrate products.  I hope and believe that this is just the beginning for the Kyma-VCU team and I fully support these kinds of collaborations that our Chief Scientist Dr. Paskova is so good at fostering.”

About Professor Morkoç and his VCU research group

For more information about Professor Morkoç  and the Morkoç research group visit and, respectively.

About Kyma Technologies

Kyma is a leading supplier of crystalline gallium nitride (GaN) and aluminum nitride (AlN) materials for a broad range of high performance nitride semiconductor device applications.

The market for nitride semiconductor devices is expected to surpass $9B by 2010. The combined addressable market for GaN and AlN substrates is expected to surpass $500M by 2010.

For more information about Kyma Technologies, visit, e-mail, or call the company directly at 919.789.8880.

Kyma is a registered trademark of Kyma Technologies, Inc.