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Register a new userSurface optical phonon scattering in N-polar GaN quantum well channels
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Uttam Singisetti
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N-polar GaN channel mobility is important for high frequency device applications. In this Letter, we report the theoretical calculations on the surface optical (SO) phonon scattering rate of two-dimensional electron gas (2-DEG) in N-polar GaN quantum well channels with high-k dielectrics. The effect of SO phonons on 2-DEG mobility was found to be small at >5 nm channel thickness. However, the SO mobility in 3 nm N-polar GaN channels with high-k dielectrics is low and limits the total mobility. The SO scattering for SiNx dielectric GaN was found to be negligible due to its high SO phonon energy.
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