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Title: Characterization of field-effect mobility at optical frequency by microring resonators

A novel characterization method is proposed to extract the optical frequency field-effect mobility (μop,FE) of transparent conductive oxide (TCO) materials by a tunable silicon microring resonator with a heterogeneously integrated titanium-doped indium oxide(ITiO)/SiO2/siliconmetal–oxide–semiconductor (MOS) capacitor. By operating the microring in the accumulation mode, the quality factor and resonance wavelength shift are measured and subsequently used to derive theμop,FEin the ultra-thin accumulation layer. Experimental results demonstrate that theμop,FEof ITiO increases from 25.3 to38.4  cm2V1s1with increasing gate voltages, which shows a similar trend as that at the electric frequency.

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Publication Date:
Journal Name:
Photonics Research
Page Range or eLocation-ID:
Article No. 615
Optical Society of America
Sponsoring Org:
National Science Foundation
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