AIXTRON has successfully installed a GaN HVPE reactor system at the Department of Optoelectronics (University of Ulm, Germany). Immediately after the installation and start-up by AIXTRON process engineers, the group has been able to grow high quality GaN on sapphire substrates. "Growth rates as high as 60 µm/h have been obtained so far. GaN layers have been grown up to 60 µm thickness. Two-inch diameter GaN films with thicknesses well above 10 µm were crack free. First PL and X-ray investigations show excellent material quality", says Dr. Markus Kamp, head of the GaN group.

The renowned University of Ulm has received the AIXTRON HVPE equipment as a member of a German GaN consortium funded by the German Ministry for Education, Science, Research and Technology (BMBF). The aim of this project is to produce thick GaN layers suited to act as substrates for the growth of high quality laser structures. The HVPE system was added to an AIXTRON GaN MOVPE reactor that has been running for several years by the University of Ulm.

The AIX VPE system is used for the growth of thick GaN with growth taking place at temperatures of up to 1100°C. Based on the proven AIXTRON HVPE system concept, the GaN HVPE system is equipped with high power multizone heaters and an enhanced cooling system for the reactor flanges as well as the heater. The AIX VPE has a capacity of 1 x 2" or 1 x 3" wafers and produces excellent film quality with good thickness uniformity. Due to its design and growth principles the low pressure AIX VPE system is extremely service friendly and efficient in throughput.