Title :
Impact of light illumination and passivation layer on silicon finite-ground coplanar-waveguide transmission-line properties
Author :
Spiegel, Solon J. ; Madjar, Asher
Author_Institution :
Intel Cellular Commun. Div., Digital Signal Processing Commun., Givat Shmuel, Israel
fDate :
10/1/2000 12:00:00 AM
Abstract :
The modeling of silicon finite-ground coplanar-waveguide (FGCPW) transmission lines is presented in this paper. It is shown that the effective substrate conductivity increases in the presence of illumination and in the presence of a passivation layer in the slot regions independently. As a result, the losses of trenched FGCPW are lower than conventional FGCPW transmission lines. The strong dependence of the substrate conductivity on illumination suggests that optically controlled attenuators can be implemented with FGCPW transmission lines exhibiting practically no phase change between the different attenuation states. A new contrast ratio for optically controlled transmission lines is derived
Keywords :
coplanar waveguides; earthing; electrical conductivity; elemental semiconductors; losses; microwave photonics; optical control; passivation; silicon; transmission line theory; waveguide attenuators; Si; Si CPW transmission-line properties; contrast ratio; coplanar-waveguide transmission-line properties; effective substrate conductivity; finite-ground CPW transmission-line properties; light illumination; losses; optically controlled attenuators; optically controlled transmission lines; passivation layer; slot regions; transmission line modelling; trenched finite ground CPW; Conductivity; Coplanar transmission lines; Lighting; Optical attenuators; Optical control; Optical losses; Passivation; Propagation losses; Silicon; Transmission lines;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
