Published online by Cambridge University Press: 26 February 2011
We report on contacts to p-type GaAs formed by a GaAs/Pt/TiN/Ag system. Ohmic behavior in this system is believed to be accomplished by the solidstate reaction of Pt with GaAs. This reaction is confined by the TiN film which is thermally stable. In addition, the TiN film acts as an excellent diffusion barrier in preventing the intermixing of the top Ag layer with GaAs or Pt. Contacts formed with such controlled reaction have important implications for the stability of shallow p-n junction devices.