Electron transport properties of low sheet-resistance two-dimensional electron gases in ultrathin AlN/GaN heterojunctions grown by MBE
نویسندگان
چکیده
A study of the transport properties of polarizationinduced 2DEGs at MBE-grown single AlN/GaN heterostructures with different growth rates is reported. It is observed that faster growth rates lead to high mobilities, approaching ∼ 1600 cm2/Vs at 300 K and ∼ 6000 cm2/Vs at low temperatures for ultrathin ( 2.3 nm AlN/GaN) heterojunctions. By using a theoretical model in conjunction with experimentally measured transport properties, it is concluded that the 300 K sheet resistances of very high density 2DEGs at AlN/GaN heterojunctions are currently limited (∼ 170 Ω/!) by interface roughness scattering, and can be further reduced by improving the growth conditions.
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MBE growth of high conductivity single and multiple AlN/GaN heterojunctions
Record-low sheet-resistance of $ 128 O=sq have been obtained in two-dimensional electron gases at ultrathin single AlN/GaN heterojunctions by optimizing the metal fluxes used in molecular beam epitaxy growth. Multiple 2DEGs have been found in AlN/GaN superlattices, with the net electron density measured 4 1 Â 10 14 cm À2 at room temperature. This very high electron density also leads to a furth...
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