Compact CPW-MS-CPW Two-Stage pHEMT Amplifier Compatible With Flip Chip Technique in V-Band Frequencies

The V-band coplanar waveguide (CPW)-microstrip line (MS)-CPW two-stage amplifier with the flip-chip bonding technique is demonstrated using 0.15 mum AlGaAs/InGaAs pseudomorphic high electron mobility transistor technology. The CPW is used at input and output ports for flip-chip assemblies and the MS transmission line is employed in the interstage to reduce chip size. This two-stage amplifier employs transistors as the CPW-MS transition and the MS-CPW transition in the first stage and the second stage, respectively. The CPW-MS-CPW two-stage amplifier has a gain of 14.8 dB, input return loss of 10 dB and output return loss of 22 dB at 53.5 GHz. After the flip-chip bonding, the measured performances have almost the same value.