The present invention provides a
radio frequency coplanar waveguide element based on a
silicon base on an insulator and a preparation method thereof. The method comprises: 1) preparing the
silicon base on an insulator, wherein the
silicon base on the insulator includes a ground floor silicon, an insulating layer and a top silicon which are stacked in order, and the lower portion of the insulating layer is provided with at least one groove of the ground floor silicon corresponding to the position of the preparation of the
radio frequency coplanar waveguide element; 2) defining a device area, removing the top chain of the device area, and exposing the upper surface of the insulating layer at the lower portion of the device area; and 3) preparing the
radio frequency coplanar waveguide element. Based on the silicon base on the graphical insulator, the radio frequency coplanar
waveguide element based on the silicon base on the insulator and the preparation method thereof obtain the coplanar
waveguide with a substrate cavity through later period
etching, the air medium in the cavity structure allows the
equivalent capacitance of the substrate to be reduced and allow the equivalent resistance to be increased so as to eliminate
fixed charge and movable charge in the SiO2 and the unfavorable factors, influencing
microwave transmission, such as Si / SiO2
system interface state, trap charge and the like, and therefore the medium loss is reduced, and the
transmission performance of the coplanar
waveguide is improved.