Circuit technique for accurate soft error rate measurements

A novel circuit technique has been developed which enables accurate measurements of Soft Error Rate (SER) due to neutrons and alpha particles. The main advantages over SRAM testing are: 1. separated SER due to the NMOS and PMOS transistors, 2. single sensitive node, 3. critical charge QCRITcan be measured. Method for determination of QCRITwith 2% accuracy is described and was verified by measurements on a test chip implemented in a 0.6µm CMOS process. Direct measurement of both QCRITand SER completely removes uncertainties due to process variations, making the proposed test circuits suitable for SER characterization of a newly-developed manufacturing process.