1 research outputs found
Ultra-Thin Silicon Chips for Submillimeter-Wave Applications
We present a process for fabricating ultra-thin silicon chips for submillimeter-wave mixing applications using SOI (Silicon On Insulator) wafers. Such chips allow the profile of the mixer substrate to be minimized within the microstrip channel, thereby simplifying RF design considerations and minimizing machining constraints. The chips feature gold beam leads, RF filter structures, and hot-electron bolometers as the non-linear element. We designed a prototype receiver to demonstrate the feasibility of the ultra-thin silicon chip technology. The receiver has a center frequency of 585GHz and accommodates both diffusion-cooled and phonon-cooled hotelectron bolometer mixers fabricated atop an ultra-thin silicon chip. The chip fits within the microstrip channel of a split-block horn antenna. Protruding from the sides and ends of the silicon chip are thick gold beam leads, which provide electrical and thermal contact between the chip and the waveguide block. In addition, the beam leads provide mechanical support to the chip, allowing the chip to be suspended within the middle of the microstrip channel between the two block halves. Ultra-thin silicon chips with beam leads will facilitate the construction of large format spectroscopic imaging arrays. Such arrays would contain an assembly of individual chips, each featuring a single nonlinear mixing element. The chips could be added, removed of replaced without disturbing the rest of the elements within the array. There are myriad potentials for such systems, examples include atmospheric research, astrophysics, and security systems