This Small Business Innovation Research (SBIR) Phase I project will develop bulk AlGaN substrates for advanced III-Nitride based semiconductor devices. The substrates will be grown by a modified hydride vapor phase epitaxy (HVPE) technique to produce thick, low dislocation density, lattice matched substrates for next generation electronic andoptoelectronic devices. Low dislocation density bulk III-Nitride substrates represent an enabling technology for a variety of devices, currently limited by heteroepitaxial growth on sapphire and SiC. Sensor Electronic Technology will use a novel HVPE growth technique coupled with substrate strain engineering to produce free standing AlGaN boules that will be used as seeds for continued bulk AlGaN development. Phase I will focus on optimizing AlGaN growth processes for a range of aluminum compositions, while establishing the feasibility of commercializing bulk substrates using this approach.<br/><br/>Commercially, III-Nitride device development and commercialization has expanded rapidly over the last decade with blue/green/white LEDs found in most cellular phones, traffic signals, and large screen displays; standards for the next generation high density DVD format being established based on blue laser diode technology; and AlGaN/GaN HFETs being targeted to replace power amplifiers and low noise amplifiers in military radar and wireless communication applications. III-Nitrides are arguably the fastest growing area of compound semiconductors at this time with new applications for these materials continually developing. Estimated revenue for III-Nitride devices exceeds $10 billion by 2007, presenting a tremendous opportunity for bulk substrate commercialization