Behavior of Space Charge in Polyimide and the Influence on Power Semiconductor Device Reliability

Polyimide is widely used in film form as a passivation material for power semiconductor devices such as Si, SiC, and GaN. The magnitude of the electric field at the edge termination area of these semiconductor devices is becoming higher due to the increase of operational voltage and/or demand for shrinking the edge termination area to increase device active area. Hence, it is concerned that the accumulation of space charge in the encapsulation and passivation material may affect the insulation performance of these devices, for example, the degradation of withstand voltage due to distortion of the internal electric field caused by space charge accumulation. To design space charge resistance of semiconductor devices, it is important to understand the space charge behavior in polyimide films with a thickness of several to several tens of micrometers. This chapter addresses practical implementation, specifications, and issues on space charge in polyimide insulation on power semiconductor devices focusing on the space charge measurements in thin polyimide films using the latest developed LIMM method and DC conductivity measurements

Photo-stimulated discharge current and charge distribution measurements on biaxially oriented polypropylene thin films

International audienc

Cartographie de charges d'espace par méthode FLIMM (complémentarité avec les méthodes PEA et TPT)

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Some aspects of coupled electrical-mechanical effects in dielectric materials

The propensity of electrically insulating materials to generate/store electrical charges leads to a panel of electromechanical phenomena that can be either exploited in applications relevant to electrical engineering, or represent limitations in the performance of insulating materials. The aim of this contribution is to describe various features of these electrical-mechanical coupling phenomena with focus on the field-induced strain measurement of charged polymers, on the charge distribution measurement by pulsed electroacoustic method and on the contribution of electromechanical effects in electrical ageing phenomena

New design of the pulsed electro-acoustic upper electrode for space charge measurements during electronic irradiation

International audienc

Study of Trapping Process in BOPP by Coupled Space Charge and Photo-stimulated Discharge Techniques

International audienceThe global market of biaxially oriented polypropylene (BOPP) film capacitors is growing constantly, as part of energy transition needs. The formation of physical or chemical defects in BOPP can lead to insulator failure due to charge build-up. It is therefore necessary to determine the amount and location of charges and to evaluate the trap energy depths to better understand conduction and aging phenomena. A test bench allowing to do combined space charge measurements by the laser intensity modulation method (LIMM) and optically excited current acquisitions by the photo-stimulated discharge method (PSD) is used to monitor charge accumulation, trap population and de-trapping scenarios. In this investigation, homocharge enhancement near the probed electrode is evidenced in a blank sample. Under light exposure for PSD measurements, charge detrapping or reactions of BOPP additives modify the charging process

Microcaractérisation de matériaux par imagerie photoacoustique sélective

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Thermal Modeling and Calibration in (F)LIMM Using an External Bias Field : Theory and Experiment

International audienc

Space Charge Measurement by Electroacoustic Method: Impact of Acoustic Properties of Materials on The Response for Different Geometries

International audienc