A second ESD threat for ESD sensitive devices with copper leads

We investigated the primary ESD event from a small air-gap discharge and induced voltage as the second ESD threat at an ESD sensitive (ESDS) device with copper leads. The discharge current waveform of the primary ESD event caused by air-gap discharge was measured at 50 mum gap width. The induced voltage in copper lead was measured versus length and width. Voltages between 3.4 V and 7.2 V were measured, which indicate an enough ESD threat to ESDS devices from the secondary event.