Development of low loss organic-micromachined interconnects on silicon at microwave frequencies

3-D CMOS Circuits Based on Low-Loss Vertical Interconnects on Parylene-N

“…Applying a dielectric layer to elevate transmission lines away from the low-resistivity Si substrate reduces the substrate interactions with the transmission lines when a relatively thick dielectric layer is used (typically 10 m) [8]. Polyimide, benzocyclobutene (BCB)-based polymers, and SU-8 are used as dielectric layers [10]- [12]. 1 Processes based on these dielectrics are either expensive, require high processing/curing temperature, or are characterized with relatively high dielectric loss.…”

“…A low-resistivity silicon wafer with bulk resistivity of [10][11][12][13][14][15][16][17][18][19][20] cm is coated with a 5-m-thick thermal silicon dioxide. The bottom metal layer (Metal 1) is a 3.5-m-thick aluminum layer formed by evaporation and lift-off processes.…”

Static Zero-Power-Consumption Coplanar Waveguide Embedded DC-to-RF Metal-Contact MEMS Switches in Two-Port and Three-Port Configuration

“…Examples include etching away parts of the lossy substrate close to the line [15]- [17]; creating hollow waveguides by bonding substrates with etched grooves [18], [19]; suspending elements of the transmission line above the lossy substrate by etching away sacrificial layers below them [20]- [23]; and using 3-D polymer or metal-printing techniques to achieve air-filled transmission lines [24]- [26] or coaxial waveguides filled with low-loss polymers [27]. Reduction of ohmic losses by increasing the metal thickness of coplanar waveguides has been shown using synchrotron radiation lithography [28].…”

Design and Simulation of Membrane Supported Transmission Lines for Interconnects in a Mm-Wave Multichip Module

“…In addition, the use of silicon allows for application of the lines to the rapidly advancing field of RF MEMS [8,9], which is also predominantly based on silicon technologies. These lines generally revolve around the fabrication of micro-shielding, and the use of a membrane or other methods of removing dielectric material from regions in which the electric field is concentrated [10,11]: these concepts are illustrated in the lines shown in Figure 1.…”

“…The reduced dielectric CPW line shown in Figure 1(c) demonstrated a loss of 1.18 dB/cm and effective permittivity of 2.7 at 60 GHz [14] (700 nm) (300 nm) (400 nm) Figure 1. Demonstrated micromachined transmission lines for use at millimeter-wave frequencies: (a) and (b) CPW geometries using raised conductors [13], (c) and (d) CPW using bulk micromachining to remove dielectric in the areas of electric field concentration [14][15][16], (e) and (f) CPW with micromachined shielding [12], (g) membrane supported CPW (microshield) [17], [7] (h) membrane supported microstrip [3], (i) membrane supported, partially shielded microstrip [3], (j) membrane supported partially shielded stripline [3], and (k) and (l) the fully shielded membrane supported striplines investigated in this paper.…”