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تسجيل مستخدم جديدDelta-doped b{eta}-Ga2O3 Films With Low FWHM Charge Profile Grown By Metalorganic Vapor-Phase Epitaxy
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We report on low-temperature MOVPE growth of silicon delta-doped b{eta}-Ga2O3 films with low FWHM. The as-grown films are characterized using Secondary-ion mass spectroscopy, Capacitance-Voltage and Hall techniques. SIMS measurements show that surface segregation is the chief cause of large FWHM in MOVPE-grown films. The surface segregation coefficient (R) is observed to reduce with reduction in the growth temperature. Films grown at 600 {deg}C show an electron concentration of 9.7 x 1012 cm-2 and a FWHM of 3.2 nm. High resolution scanning/transmission electron microscopy of the epitaxial film did not reveal any significant observable degradation in crystal quality of the delta sheet and surrounding regions. Hall measurements of delta-doped film on Fe-doped substrate showed a sheet charge density of 6.1 x 1012 cm-2 and carrier mobility of 83 cm2/V. s. Realization of sharp delta doping profiles in MOVPE-grown b{eta}-Ga2O3 is promising for high performance device applications.
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We report on the growth and characterization of metalorganic vapor-phase epitaxy-grown b{eta}-(AlxGa1-x)2O3/b{eta}-Ga2O3 modulation-doped heterostructures. Electron channel is realized in the heterostructure by utilizing a delta-doped b{eta}-(AlxGa1-
x)2O3 barrier. Electron channel characteristics are studied using transfer length method, capacitance-voltage and Hall measurements. Hall sheet charge density of 1.06 x 1013 cm-2 and mobility of 111 cm2/Vs is measured at room temperature. Fabricated transistor showed peak current of 22 mA/mm and on-off ratio of 8 x 106. Sheet resistance of 5.3 k{Omega}/Square is measured at room temperature, which includes contribution from a parallel channel in b{eta}-(AlxGa1-x)2O3.
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