ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
AlxGa1−xAs–GaAs structures with thin (400–1000 A(ring)) Cr-doped or unintentionally doped AlxGa1−xAs layers (0.3≤x≤1) were grown on n+ GaAs substrate by molecular-beam epitaxy. The AlxGa1−xAs–GaAs interface and the insulating properties of thin AlxGa1−xAs layers at 300 K have been studied by capacitance–voltage and current–voltage measurements, respectively. An AlxGa1−xAs–GaAs interface state density in the lower 109 eV−1 cm−2 range was obtained. The insulating properties of thin AlxGa1−xAs layers were found to be controlled by AlxGa1−xAs–GaAs interface band offsets (ΔEo,ΔEv) and metal–AlxGa1−xAs barrier height ΦBn in accumulation and deep depletion, respectively, rather than by AlxGa1−xAs bulk properties such as specific bulk resistivity. Furthermore, required electrical properties of insulating layers employed in metal–insulator–semiconductor structures are discussed using a self-consistent heterostructure model based on Poisson's equation and current continuity equations. Finally, a fundamental equation for the formation of inversion channels has been derived. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.360416
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