Engineered Schottky barrier diodes for the modification and control of Schottky barrier heights

摘要

A technique for fabricating controlled Schottky barrier heights to GaAs over the entire band gap is demonstrated. Thin, highly doped semiconductor layers at the metalhyphen;semiconductor interface allowed the reproducible control of the effective barrier height onnhyphen;type GaAs from near zero (i.e., ohmic behavior at 300 K) to 1.33 eV (the band gap equals 1.43 eV at 300 K) with diode ideality factors 1.02le;nle;1.21. Molecularhyphen;beam epitaxy was used to grow GaAs epitaxial layers withinsitudeposited Al metal layers, resulting in diodes with nearly ideal electrical and structural characteristics. Electrical characterization by currenthyphen;voltage (Ihyphen;V) and capacitancehyphen;voltage (Chyphen;V) techniques, models for theseIhyphen;VandChyphen;Vcharacteristics, and structural characterization by high resolution transmission electron microscopy lattice images are presented. Implications of this work for models of Schottky barrier formation are discussed, as well as some applications for these lsquo;lsquo;engineered Schottky barrier diodes.rsquo;rsquo;