Properties of PVD AlN for LED Applications

AlN Physical Vapor Deposition (PVD) system is successfully developed by Beijing NAURA Microelectronics Co., Ltd. for 2-6 inch wafers. PVD AlN buffer layer is inserted in GaN substrate in LED manufacturing process to effectively improve the performance of LED optoelectronic devices, increase the Metal Organic Chemical Vapor Deposition (MOCVD) throughput and reduce production cost. GaN film grown epitaxially on the top of PVD AlN film exhibits a very smooth surface and narrow Full Width at Half Maximum (FWHM) peaks at (002)/(102), which are 90/140 arcsec, respectively. TEM observation and chip analysis show that the atomic bonding and arrangement at the GaN/AlN interface are more regular, which leads to less dislocation defects during subsequent epitaxial growth of GaN/MQW.