Broadband balun and phase noise measurement system design for RFIC testing

This research mainly focuses on test cost reduction for RF ICs. First, differential circuit measurements with a two port network instrument are discussed. Many companies and academic researchers use a four port instrument to measure their differential RF chips. This is the simple and accurate method, however, the test instruments are very expensive compared to a two port instrument, especially for high frequency (>20GHz) system. Alternative method is using balun to convert the differential signal into a single-ended signal, and then measures it with a two port instrument. This method can save the cost of the expensive instruments but need at least 6 different test setups. The time is another test part of test cost. By integrating the balun in a RF differential probe, the measurement can be simplified with a two port instrument. Second, for building a balun integrated probe, a new analysis is introduced for the Marchand balun. The new method takes the termination impedance variation into account. Third, a new closed form equation based on conformal mapping method for extracting the broadside coupled transmission line, is introduced and verified with FEM method. Fourth, a balun integrated probe is designed, fabricated, and measured in Cascade probe technology. Finally, the embedded test system or Built-in Self Test (BIST) for the phase noise is discussed. Testing and verification of the RF and microwave components are major parts of the total test cost. Over the years, various methods have been studied for reducing the test cost. A new method is an on-wafer phase noise measurement which is a very economical method while keeping a high level accuracy. Through the noise and system analysis, the proposed system specifications are determined and implemented in IBM8HP technology. Measurement indicates better performance than the commercial external systems up to 1.5GHz.