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Fan Ren Charles A. Stokes Professor Semiconductor Materials and Devices Email: ren@che.ufl.edu Phone: (352) 392-4727 317 Chemical Engineering Building

Faculty Web Page - Patents, Publications, Research Details, Equipment


Brief Description of Current Research

Wide Energy Bandgap Electronic Devices

Wide energy-bandgap electronic devices, typically based on GaN films, have been extensively investigated in recently years due to their unique optical and electronic properties and exciting potential applications.  In particular, visible and ultraviolet lasers and light-emitting diodes for have been demonstrated for display and data-storage applications.  This effort is part of a consortium chartered with developing the requisite technologies for high power and high breakdown voltage electronics based on GaN materials.  Contact metallization, passivation, device integration, and characterization studies are routinely performed using state-of-the-art equipment.  This work has been supported by the Office of Naval Research, the Electric Power Research Institute, and the Defense Advanced Research Projects Agency.

 Semiconductor Device Passivation

This research program aims to develop the basic science and technology of low-temperature deposition methods that can provide reliable and reproducible passivation for compound semiconductor devices, such as pseudomorphic AlGaAs/InGaAs/GaAs PHEMTs, GaAs MESFETs, GaAs based HBTs and InGaAs/InP based HBTs, and GaN based devices.  There are three major topics under investigation:

• Deposition of silicon-nitride based dielectrics using different precursors such as SiH₄/NH₃, SiH₄/N₂, SiD₄/ N₂, SiD₄/ND₃, and hydrogen-free dielectric, and incorporation of a D, O, or N plasma treatment into to reduce the occurrence of dangling bonds.
   
• Optimization of the dielectric material quality with different deposition techniques and conditions. The systems considered include conventional plasma enhanced chemical vapor deposition (PECVD), down-stream electron cyclotron resonance chemical vapor deposition (ECRCVD), and inductively coupled plasma chemical vapor deposition (ICPCVD).
   
• Characterization of device degradation mechanisms related to deposition techniques, dielectric film quality, and the hydrogen passivation effect.

Selected Patents

• “GaN-type enhancement MOSFET using heterostructure”, Abernathy, Irokawa, Pearton, Ren, US 6,914,273 (2005).
  
  
• "Air Isolated Crossovers", Kossives, Tai, Ren, US 6,683,384(2004).
  
  
• "Method of Making An Article Comprising An Oxide Layer on A GaAs-Based Semiconductor Body", Chen, Cho, Hong, Hobson, Kuo, Kwo, Murphy, Ren, US 6,271,0698(2001).
  
  
• "Method of Forming A T-Shape Gate", Lothian, Ren, Weiner, US 5,981,319(1999).
  
  
• "Article Comprising An Oxide Layer on GaN", Hong, Hobson, Lothian, Mannaerts, Ren, US 5,912,498(1999).
  
  
• "GaAs Based MOSFET, And Method of Making Same", Cho, Hong, Hobson, Mannaerts, Ren, US 5,903,037(1999).
  
  
• "Method of making an article comprising an oxide layer on a GaAs-based semiconductor body",, Hong, Hobson, Lothian, Mannaerts, Ren, European 993055128(1999).
  
  
• "Method of making an article comprising an oxide layer on a GaAs-based semiconductor body", Hong, Hobson, Lothian, Mannaerts, Ren, European 993055128(1999)
  
  
• "Improved Air Isolation Crossovers", Kossives, Tai, Ren, European 98307916(1998).
  
  
• "Article Comprising An Oxide Layer on GaN and Method of Making the Article", Hobson, Hong, Lothian, Mannaerts, Ren, European, 98307928(1998).

Selected Publications

• “Comparison of MOS and Schottky W/Pt-GaN Diodes for Hydrogen Detection", B.S.Kamg, S.Kim, F.Ren, B.P.Gila, C.R.Abernathy and S.J.Pearton, Sensors and Actuators, Vol. B105, 232-236 (2005).
   
• “Detection of CO Using Bulk ZnO Schottky Rectifiers", B.S. Kang, F. Ren, K. Ip, Y. W. Heo, B.P.Gila, C. R.Abernathy, D.P.Norton and S.J.Pearton, Appl. Phys. Vol. A, 259-2616 (2005)
   
• “Thermal Degradation of Electrical Properties And Morphology of Bulk Single-Crystal ZnO Surfaces", R. Khanna, K. Ip, Y.E. Heo, D.P. Norton, S.J.Pearton and F.Ren, Appl. Phys. Lett.. Vol. 85, 3468-3470(2004).
   
• “Electrical Transport Properties of Single ZnO Nano-Rods", Y.W. Heo, L.C.Tien, D.P.Norton, B.S.Kang, F.Ren B. Gila, and S.J.Pearton, Appl. Phys. Lett. Vol. 85, 2002-2004 (2004).
   
• “Effect of Deposition Conditions and Annealing on W Schottky Contacts on n-GaN", R. Mehandru, S. Kang, S.Kim, F. Ren, I. Kravchenko, W.Lewis, and S.J.Pearton, Materials Sci. in Semicond. Processing, Vol. 7, 95-98 (2004).
   
• “Enhanced Functionality in GaN and SiC Devices By Using Novel Processing", S.J.Pearton, C.R.Abernathy, B.P.Gila, F.Ren,J.M.Zavada and Y.D.Park, Appl. Phys. Lett., Vol. 48, 1965-19746 (2004).
   
• “Lateral Schottky GaN Rectifiers Formed By Si+ Ion Implantation", Y. Irokawa, J. Kim, F. Ren, K.H. Baik, B.P. Gila, C. R. Abernathy, S.J.Pearton, C.C.Pan, G.T.Chen and J.I. Chyi, J. Electronic Materials, Vol. 33, 426-430 (2004).
   
• “SiC Via Holes by Laser Drilling", S. Kim, B.S.Kang, F. Ren, J.,D’entremont, E.Blumenfeld, T. cordock and S.J.Pearton, J. Electronic Materials, Vol. 33, 477-480 (2004).