Test Structure for High Voltage LD-MOSFET Device Mismatch Investigations

A characterization setup for high voltage (HV) LD-MOSFET mismatch and variability determination is presented. Devices are aligned in rows and columns for gate and drain bias multiplexing and special HV-switches for voltages up to 50 V are controlled by externally generated digital signals. Automatic DC measurements can be performed on up to 4992 HV-NMOSFETs. The circuit designs of the HV-switches are described in detail and characterization data gained during functionality evaluation are presented. Variability data are provided for both short and long distance matching characterization.