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Title: Controlled Si doping of β -Ga2O3 by molecular beam epitaxy

We report controlled silicon doping of Ga2O3 grown in plasma-assisted molecular beam epitaxy. Adding an endplate to the Si effusion cell enables the control of the mobile carrier density, leading to over 5-orders of magnitude change in the electrical resistivity. Room temperature mobilities >100  cm2/V s are achieved, with a peak value >125  cm2/V s at a doping density of low-1017/cm3. Temperature-dependent Hall effect measurements exhibit carrier freeze out for samples doped below the Mott criterion. A mobility of 390  cm2/V s is observed at 97  K.

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Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Applied Physics Letters
Medium: X
Sponsoring Org:
National Science Foundation
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