Lossy dielectrics are developed to absorb microwave energy over specific frequency bands by carefully changing their complex permittivities (dielectric constant and loss tangent). Sienna Technologies Inc. has developed a complete line of AlN-based lossy dielectrics to replace toxic BeO-SiC composites in microwave applications such as severes, terminations, slot mode absorbers and loss buttons. Sienna’s state-of-the-art STL-100 and STL-150D materials provide microwave energy absorption over a wide frequency range, high thermal conductivity, no vacuum outgassing, and brazeability to metals. Standard grades include STL-100U3, STL‑100U7, STL-100F, STL-100HTC, STL-150D75, STL-150D09, and STL-150D11. The microwave dielectric properties of both STL‑100 and STL-150D family of materials can be tailored to meet specific microwave absorption requirements.
Low loss, high thermal conductivity, non-toxic ST-200 AlN provides a viable replacement to BeO at a comparable price without BeO’s toxicity concerns for radio frequency (rf)/microwave output/input windows; helix support rods and collector rods for high power microwave tubes; and microwave terminations and resistors. Sienna, through its strategic alliance with precision machining facilities, can deliver the exact component you need.
