N-type Mobility Research Articles

Sputter Deposition of Indium Nitride on The (111) Face of Elemental and Compound Semiconductors

ABSTRACTThe structure, morphology, and transport properties of thin films of InN grown on several cubic semiconductors has been studied as a function of substrate temperature. Films were deposited using rf-magnetron sputtering onto the (111) face of GaAs, Ge, Si and ZrO2. In general, the film structure is such that (00.1)InN parallels the (111) plane of the cubic substrate above some deposition temperature. The in-plane structural coherence duplicates the magnitude of the calculated lattice mismatch between InN and the substrate. Electrical transport properties for growth onto (111) ZrO2 were characterized by n-type carrier concentration and mobilities ranging up to 44 cm2 /Vsec. A morphology-induced decrease in electrical mobility is observed for deposition temperatures above 350°C, as shown by SEM.

Epitaxial growth of ErAs on (100)GaAs

Successful growth of (100)ErAs single-crystal films on (100)GaAs has been demonstrated. Reflection high-energy electron diffraction, low-energy electron diffraction (LEED), and Rutherford backscattering with channeling indicate single-crystal growth. LEED from the ErAs shows a (1×1) structure. Overgrowth of GaAs on ErAs is found to be difficult due to the GaAs not wetting the ErAs surface and hence resulting in island growth. For a 150-Å-thick film metallic behavior is observed with resistivities 17 and 70 μΩ cm at 1.5 K and room temperature, respectively. Low-temperature Hall measurements show the conduction to be dominated by electrons with an effective n-type mobility in the range 360 cm2/V s at 1.35 K.

Effect of As4/Ga flux ratio on electrical properties of NID GaAs layers grown by MBE

The effect of the As4/Ga flux ratio R on NID GaAs layers has been studied when the MBE growth chamber is used without baking after reloading the arsenic cells, in order to increase the productivity of the system. In these conditions a change from p- to n-type is observed when R is varied from 1.8 to 14. Satisfactory p-type material is obtained at R ? 3 (p = 2.0 × 1014 cm?3, ?77 K = 6200 cm2 V?1 s?1). The maximum n-type mobility occurs at R = 5.8. Photoluminescence spectroscopy confirms the effect of R on the incorporation of residual impurities.