Highly Resistive Iron-Doped AlInAs Layers Grown by Metalorganic Chemical Vapor Deposition

We report for the first time highly resistive iron-doped AlInAs layers grown by metalorganic chemical vapor deposition (MOCVD) using a popular iron doping source, (C₅H₅)₂Fe. The linear relationship between Fe atom concentration of Fe-doped AlInAs layers, which was measured by SIMS analysis, and (C₅H₅)₂Fe flow rate was obtained. To evaluate the effect of Fe doping quantitatively, samples of Si-doped n-AlInAs layers were prepared. The relation between carrier concentration and Fe atom concentration of the layers suggested that one Fe atom killed one carrier of n-type AlInAs. An Fe-doped AlInAs layer, with undoped AlInAs layers, which had a residual carrier concentration of 1∼2×10¹⁵ cm^-3, showed highly resistive characteristics. We found a deep trap with an activation energy of 0.7 eV using photoexcited DLTS, which may cause compensation.