Photonic circuits can transmit data signals in a much higher speed thanconventional electronic circuits. However, miniaturization of photonic circuitsand devices is hindered by the existence of light diffraction limit. A promisingsolution to this problem is by exploiting plasmonic systems for guiding andmanipulating signals at optical frequencies. Plasmonic devices are generallycomposed of noble metals and dielectrics, whose interfaces can confine surfaceplasmon polaritons, a hybrid wave that is free of diffraction limit. Plasmonicwaveguides and devices are serious contenders for achieving next-generationphotonic integrated circuits with a density comparable to the electronic counterpart. Until now, variuos kinds of plasmonic waveguides with the ability to achieve highly density optical circuits were proposed. However, only hybrid plasmonic waveguide because of having long propagation length and high mode confinement received much attention between researchers. This thesis, proposed a new justify; LINE-HEIGHT: 14.2pt; MARGIN: 0cm 0cm 0pt; unicode-bidi: embed; DIRECTION: ltr; mso-line-height-rule: exactly" Keywords: Surface plasmon polaritons, Figures of merit, SOI substrate, coupling length