A compact, broadband, two-way Wilkinson power divider/combiner is presented, created in 0.18-𝜇m CMOS for use between 60 and 90 GHz. The suggested design uses stacked M5–M6 slow-wave trans- mission lines to shorten the physical quarter-wave length without need- ing extra matching capacitors, which allows for a condensed, meander- ing arrangement. Because of the strong broadside coupling between the stacked conductors, the suggested line has a phase constant about 43% greater than the standard structure at 75 GHz. This lets the necessary 90◦ electrical length be achieved with a considerably shorter physical line. Rather than using M1 as a direct shielding ground, a recurring M1 structure is put under the signal lines as an electromagnetic field-control layer, while the actual RF ground reference is made by the conductive ground under the substrate. Furthermore, an RC isolation network offers frequency-shaped odd-mode damping for wideband isolation. A back- to-back setup is used for precise on-wafer characterization. The mea- surements show an extra insertion loss of 0.5 dB at 75 GHz, a return loss exceeding 20 dB at all ports, and an isolation greater than 34 dB from 60 to 90 GHz within a small 0.086 mm2 core area. The suggested structure works well for small mmWave CMOS front-end uses.