Solution for the Drift Problem of the Chip in the Packaging Process

Abstract

This paper analyzes the drift phenomenon of the chips appearing in the packaging process of the fast recovery diode (FRD), and proposes an effective process to solve this problem. In order to improve the trade-off characteristics of fast recovery diodes, lifetime control methods, such as electron irradiation, high-energy ion implantation and so on, are often introduced in the chip manufacturing process. The chips described in this paper use the lifetime control method of electron irradiation. The problem of chips drift during the packaging process has been found. In this paper, by comparing different back metal schemes, comparing and analyzing the products of different manufacturers, the cause of chips drift is ultimately located in the annealing process after electron irradiation. The result of this paper shows that the chips drift phenomenon can be solved by adjusting the process steps.