Temperature-Compensated Devices Using Thin Layer With Negative TCD

This letter evaluates the applicability of TeO₂ thin films as an attractive alternative over conventional SiO₂ layers in the field of temperature compensation of various devices. It is reported that the processing environment during TeO₂ growth plays an important role in defining its negative temperature coefficient of delay (TCD), and the magnitude of TCD increases continuously from -1.862times10³ ppmmiddotdegC^-1 to -9.883times10³ ppmmiddotdegC^-1 with an increase in the oxygen percentage from 25% to 100% in the processing gas mixture. A very low thickness of 0.008lambda for the TeO₂ over layer (in comparison to the 0.32lambda-thick SiO ₂ layer) is required for achieving a zero-TCD device without degrading its performance