The 3300 sq. ft. Solid State Sciences Laboratory focuses on epitaxial growth, processing, and characterization of compound semiconductor materials such as silicon carbide and the III-Nitrides (GaN, AlN, InN, and alloys), which are used in high frequency, high power, and high temperature electronic devices, as well as short-wavelength optoelectronic devices.  Research capabilities exist for nanoscale epitaxial growth, as well as the fabrication and characterization of test structures and devices based on these materials.  Besides the major materials growth systems, the laboratory facilities include laminar flow fume hoods, Nomarski optical microscopes, and a dark-room for photolithography using a Karl Suss soft-contact mask-aligner.  Metallization, ion implantation, and materials characterization facilities are also available.

Metalorganic Chemical Vapor Deposition (MOCVD) System
for Epitaxial Growth of III-Nitrides and Silicon Carbide

Dual vertical reactor system with a 15 kW RF induction power supply that can heat a substrate up to 1700 deg C.  Process can be run at either low or atmospheric pressure.  The system has two liquid sources and six process gases in addition to hydrogen and argon gases.  This system is dedicated to growth of epitaxial wide band gap semiconductors and in-situ oxidation of silicon carbide.   The dual reactors, separated by a gate valve, allow epitaxial growth by CVD as well as in-situ oxidation and nitridation without cross-contamination.   Epilayers can be immediately oxidized without exposure to outside atmosphere.   This enables oxidation and nitridation to take place on the prestine surface of the samples.  In-situ surface modification and introduction of additives provide a controlled atmosphere for oxidation or nitridation.  The controlled atmosphere allows the study of the effects of interfacial impurities and defects at the insulator/semiconductor interface.  Results of such studies can then be translated to conventional processing techniques. This MOCVD system has both aluminum and gallium liquid sources (TMA and TMG) as well as ammonia gaseous source.  An indium liquid source will soon be added. Presently this system can be used to grow AlN, GaN, and AlGaN.  With the availability of indium, this system will have the additional capability of growing InN and InGaN.  The III-nitrides thin films can be used for LEDs, HEMTs, and solar cells.
This system presently supplies all the device structures used in the device fabrication and characterization projects at Auburn University.
 

III-Nitrides
Molecular Beam Epitaxy

                 Mask Aligner                                     Nomarski Microscope

 206 Allison Laboratory  |  Department of Physics  |  Auburn University  |  Auburn  | Alabama 36849
cctin@physics.auburn.edu