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Analysis of a Novel Strained Silicon RF LDMOS

Authors: V.Fathipour, M. A. Malakootian, S. Fathipour, M. Fathipour


In this paper we propose a novel RF LDMOS structure which employs a thin strained silicon layer at the top of the channel and the N-Drift region. The strain is induced by a relaxed Si0.8 Ge0.2 layer which is on top of a compositionally graded SiGe buffer. We explain the underlying physics of the device and compare the proposed device with a conventional LDMOS in terms of energy band diagram and carrier concentration. Numerical simulations of the proposed strained silicon laterally diffused MOS using a 2 dimensional device simulator indicate improvements in saturation and linear transconductance, current drivability, cut off frequency and on resistance. These improvements are however accompanied with a suppression in the break down voltage.

Keywords: LDMOS, High Frequency MOSFET, Design of RF LDMOS, Strained-Silicon

Digital Object Identifier (DOI):

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