-The paper tackles the issue of designing tunable Marchand baluns and provides an insight on available approaches for integrating the structure in a semiconductor process. Limitation of the approach and possible solutions are also discussed. The analysis is applied to a Marchand balun fabricated in IBM 8HP SiGe process to demonstrate the feasibility of the approach. A mix of measured and simulated data is used to support the analysis at Q band. State-of-theart performance is achieved.