Dielectric membranes manufactured by isotropic etching of <111> oriented silicon for microwave applications

The paper presents the manufacturing of thin dielectric membranes by isotropic etching vs. anisotropic etching of silicon. The isotropic etching technique of <111> oriented silicon was developed in our laboratories for the first time. The quality of membranes was investigated by atomic force microscope (AFM) analysis. There were manufactured meander and S-line inductors and interdigitated capacitors supported on thin dielectric membranes. Atomic force microscope analysis was used for the membrane quality testing. Very low values of the parasitic capacitances were obtained as effect of micromachining of these devices.