Methodologies for Low-Cost Testing and Self-Healing of RF Systems

During the last decade, System-On-Chip (SOC) approach has emerged to integrate digital, analog and RF circuits on a single chip to miniaturize wireless communication systems. Although SOC approach is a promising solution for the miniaturization of RF systems, it is limited by low-Q passives and substrate coupling. As an alternative to the SOC approach, System-On-Package (SOP) and System-In-Package (SIP) approaches have shown potential to provide better integration of digital, analog and RF functionalities. Even though advances in these technologies have reduced many problems associated with manufacturing complex integrated RF systems, the manufacturing cost of RF systems is still a major concern for industry because of high test cost and yield issues of RF circuits.;This thesis proposes a multifaceted production test and post-manufacture yield enhancement framework for RF systems. This framework uses low-cost test and postmanufacture calibration/tuning techniques. Since the test cost and the yield of the RF circuits/sub-system directly contribute to the manufacturing cost of RF systems, the proposed framework minimizes overall RF systems' manufacturing cost by taking two approaches as shown in Fig.1. In the first approach, low-cost testing methodologies are proposed for RF amplifiers and integrated RF substrates with an embedded RF passive filter and interconnect. Techniques are developed to test RF circuits by the analysis of low-frequency signal of the order of few MHz and without using any external RF teststimulus. Oscillation principles are used to enable testing of RF circuits without any external test-stimulus. In the second approach, to increase the yield of the RF circuits for parametric defects, RF circuits are tuned to compensate for a performance loss during production test using on-board or on-chip resources. This approach includes a diagnosis algorithm to identify faulty circuits within the system, and performs a compensation process that adjusts tunable components to enhance the performance of the RF circuits. In the proposed yield improvement methodologies, the external test stimulus is not required because the stimulus is generated by the RF circuit itself with the help of additional circuitry and faulty circuits are detected using low-cost test methods developed in this research. As a result, the proposed research enables low-cost testing and self-healing of RF systems.