Millimeter wave metamaterial band-pass filter by femtosecond laser ablation

In this paper, design, fabrication and characteristics of a millimeter-wave band-pass filter (BPF) on 40 GHz are presented. The device was designed in a metamaterial approach being conceived as a series of CRLH CPW artificial lines. The BPF was fabricated on silicon substrate (0.5 mm thickness), for future integration in complex mm-wave circuits. In order to fabricate this device, a standard photolithographic and a direct laser writing method were used to microprocess a metallization of 2000 Å Au / 500 Å Cr deposited on silicon. Using these two techniques, millimeter wave BPFs were obtained and measured. Also, a comparison between the two fabrication methods is done.