Study On Burn-in Screening Technology Of Power Bare Die

Know Good Die (KGD) is one of the key technologies to improve the pass-rate of the MCM (Multi-Chip Module) products. The power bare die has the characteristics of large current and high temperature, so the KGD technology of general bare die cannot be used in the power bare die. The power bare die has applied widely in many electronic systems, so it's meaningful and urgent to study the burn-in and screeing technology of power bare die. In this paper, the main study is about the testing and burn-in screening technology of VDMOS (Vertical Diffused MOSFET), as one example of power bare die.Six screening items for the power bare dies have been proposed on the base of testing and screening technology of the package devices. Except the burn-in, the other five screening items can refer to GJB128A-97. Due to the large current and high temperature under burn-in screening of power bare die, the real time temperature control is necessary. Thus techniques of junction temperature measurement are analyzed, which provides a theoretical basis for junction temperature control of the power bare die.It is found that the existing DC power burn-in method cannot be applied to the power bare die directly when studying the power burn-in screening. So a pulse power burn-in method has been proposed, which measure junction temperature by thermal parameters and control junction temperature by adjusting the power, frequency and duty of pulse to ensure the junction temperature meet the requirement of burn-in. Theoretical analysis and experiments demonstrate that continuous pulse power burn-in method is feasible. Finally a serial continuous pulse power burn-in procedure for multi-device is proposed.Finally, a testing and burn-in screening procedure for the power bare die has been firstly implemented. The experiment result shows that the testing and burn-in screening procedure is feasible without damage of the bare die and carrier.