30 Apr
Benefits of Non Polar GaN touted in newly published book edited by Kyma Technologies Chief Scientist

Kyma Technologies, Inc., a leading supplier of ultra-high purity crystalline gallium nitride (GaN) and aluminum nitride (AlN) materials and related products and services, announced the publication of a new book entitled, "Nitrides with Nonpolar Surfaces: Growth, Properties, and Devices." Published by Wiley-VCH, Weinheim, Germany, the book is edited by Dr. Tanya Paskova, who recently joined Kyma Technologies as their Chief Scientist.


The book represents a detailed review of progress in the preparation and application of novel GaN materials structures based on nonpolar crystallographic orientation. The potential importance of nonpolar GaN especially for optoelectronic device applications such as light emitting diodes and laser diodes is great and progress in development and application of nonpolar GaN materials continues at breakneck pace even since the writing of this book.

Kyma CEO and President Keith Evans commented, "The publication of this book represents a great opportunity for readers to gain a good understanding of the intense activities worldwide to realize better nonpolar GaN materials and to use them in several interesting device applications. Tanya's role as both the book editor and a key contributor is a reflection of great overall achievements in and understanding of GaN materials fabrication and characterization."

World-renown GaN materials and device experts Jim Speck and Steve DenBaars, who are both professors at UCSB, wrote the book's preface, wherein they stated, "Since this volume was prepared, the progress in nonpolar and semipolar nitrides has been remarkable." Much of the nonpolar GaN described in the book was fabricated using heteroepitaxial growth techniques, which present challenges in terms of dislocation density and presence of stacking faults. The very recent achievements in LED and LD performance, however, have been realized by utilizing native nonpolar GaN substrates.

In 2006 Kyma announced its own native nonpolar GaN substrate product line based on slicing nonpolar GaN substrates from low defect density GaN boules.

"These native substrates are very low in defect density and are essentially free of stacking faults, offering superior substrate quality for nitride-based devices with nonpolar surfaces free of both spontaneous and piezoelectric polarization electric fields," added Dr. Paskova.

Kyma has been supplying native nonpolar GaN products to leading university, government, and corporate R&D groups worldwide. Several scientific presentations and publications on ultraviolet, blue, and green LEDs have resulted in partnership with Professor Asif Khan's group at University of South Carolina, Professor Russ Dupuis's group at Georgia Institute of Technology, and Professor Christian Wetzel's group at Rensaeller Polytechnic Institute (RPI).

About Nonpolar GaN

Non-polar GaN substrates are of great interest to the nitride semiconductor device community because they enable the deposition of improved device active regions that can be used to realize new and improved high performance optoelectronic and electronic nitride semiconductor devices. Leading semiconductor experts have predicted that non-polar GaN will enable higher quantum efficiencies and improved electrical characteristics for light emitting diodes (LEDs) and laser diodes and will enable the development of very high performance enhancement mode (e-mode) high electron mobility transistors (HEMTs). While such predictions have been partially corroborated by experiment, previous attempts to fabricate devices on non-polar GaN were severely hampered by the presence of very high defect densities in the active regions which had origins in the substrates and which derived from the heteroepitaxial approaches used in the non-native approach to their fabrication. A native boule growth approach provides a direct route towards slicing and polishing non-polar GaN and provides key benefits in terms of lower defect densities, process scalability, and manufacturing cost structure.

About Kyma Technologies

Kyma was launched in 1998 as a spin out of North Carolina State University's Materials Science and Engineering Department to pursue the development of gallium nitride (GaN) and aluminum nitride (AlN) substrates for a broad range of high performance nitride semiconductor device applications.

Kyma's diversified product offering includes: ultra-low defect density native (free-standing) GaN in customer-defined orientation including polar (c-plane Ga-face or N-face) and non-polar (a-plane and m-plane), GaN and AlN templates grown on sapphire and other substrates, and ultra-high purity polycrystalline GaN.

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, please visit our website www.kymatech.com, send us e-mail at This email address is being protected from spambots. You need JavaScript enabled to view it. , or call the company directly at 919.789.8880.

Kyma is a registered trademark of Kyma Technologies, Inc.