ESD-Event Detector for ESD Control Applications in Semiconductor Manufacturing Factories

An electrostatic discharge (ESD)-event detector has been designed and fabricated in a single chip to detect and alarm the ESD events in semiconductor or integrated circuit (IC) manufacturing environments. The experiment measured results showed that the peak-to-peak voltage of the detected signal during an ESD event has a strong correlation with its ESD-stress voltage level. The proposed ESD-event detector can determine a detected signal to be an ESD pulse if its signal amplitude is higher than the settable threshold and its duration time is under 500 ns. The ESD-event detector circuit, including a 450 MHz logarithmic amplifier, a comparator, and a time discriminator, has been implemented in a single chip with a total silicon area of only 693 × 563 μ${\mathbf{m}}^2$ and fabricated by 0.18-μm CMOS process. The detector can detect high-frequency transient signals up to 450 MHz, which has been successfully verified in the field tests by detecting the signals generated from the ESD generators, the human-body model tester, and the field-induced charged-device model tester. The proposed ESD-event detector can efficiently perform the real-time ESD monitoring applications in the IC and semiconductor manufacturing factories.