Broadband dielectric characteristics of PEEK material used for packaging press pack IGBT devices

In this paper, the broadband dielectric characteristics of PEEK material used in press pack IGBT devices are measured by the method of frequency-domain dielectric spectroscopy under temperatures from -40 °C to 180 °C and frequencies from 10 mHz to 1 MHz. The mechanism of the broadband dielectric response of PEEK material is analyzed and can be accurately described by dual-relaxation Cole-Cole model. The effects of temperature on broadband dielectric characteristics of PEEK material are analysed with thermal analysis results of Differential Scanning Calorimeter. When the temperature is above the glass transition temperature (153.5 °C), the complex relative permittivity of PEEK material increases sharply. The results of this paper can provide useful references for insulating packaging design of press pack IGBT devices under electrothermal composite stress.