March 14, 2001–Santa Ana, California–Microsemi Corp. has received a patent for its breakthrough Monolithic Microwave Surface Mount semiconductor packaging technology that eliminates costly ceramic and metal packages commonly used for components operating at frequencies up to 12 GHz in high-speed microwave applications.
The U.S. patent, No. 6,187,611, covers the unique manufacturing process Microsemi uses to create high-speed hermetic flip chip components that are easily mounted on circuit boards and require 1/10th the space of conventional devices.
“Until now, manufacturers of fixed microwave and high speed wireless LAN circuits had no choice beyond ceramic or metal packages for these frequencies because parasitic limitations prevent the use of plastics,” explains John Caruso, general manager of the company’s Microwave division. “We’ve solved that problem and are shipping surface mount silicon switches and tuning components capable of 12 GHz performance.”
In the patented MMSM manufacturing process, metallization and etching techniques are used to create semiconductor devices that are packaged during the fabrication of the wafer itself. Interconnections are made by precise photolithographic methods that eliminate wire bonding, another source of parasitic problems. Combined with their substantially reduced size, the resulting products minimize parasitic capacitance. The process also is credited with an ability to provide consistency both across each wafer and from water to wafer.