In this work, a prognostic/diagnostic approach was made to use knowledge-based system to accelerate the process/equipment faults detection and classification. The domain knowledge within the fab environment can be either captured by PHM systems or populated by the experienced engineers. With the implementation of the proposed PHM system, domain knowledge stored in the PHM-equip and PHM-APC (advanced process control) subsystems will feed forward and feed backward through the entire process flow. For example, device information from the PHM-BE (back end) subsystems will be easily shared with process and equipment engineers. Likewise, process information from PHM-Equip and PHM-APC subsystems can also be shared with device and test engineers to achieve a fab-wide collaboration environment. These PHM systems are executed in a formal factory automation environment with all the correct compliances for equipment interface and integration plus MES connectivity