A micromachined W-band iris filter

A micromachined W-band iris filter was successfully demonstrated using micro hot embossing and selective electroplating technologies. The filter design follows the insertion loss method with a Chebyshev polynomial to synthesize the desired spectral responses and numerical simulations were performed using the finite-element tool, high frequency structure simulator (HFSS), to study the effects of iris thickness on the bandwidth and center frequency. The measured prototype filter performance has a transmission loss of -3.49 dB and a return loss of -18 dB at the resonant frequency of 95 GHz. The filter has a bandwidth of 3.5 GHz and a rejection loss of better than -50 dB, while the loaded quality factor is 27.27. This plastic, low-cost manufacturing process opens up opportunities in replacing the expensive metallic components and integrated 3D manufacturing for current and future millimeter-wave systems.