Preparation method of insulated gate bipolar transistor

Abstract

The invention discloses a preparation method of an insulated gate bipolar transistor (IGBT), which is characterized by comprising the following steps of: manufacturing bumps on pressure welding points of a collector electrode and a grid electrode on the front surface of a wafer after the front surface of the IGBT wafer is manufactured; performing wafer-level plastic package on the front surface of the wafer to form a plastic package layer; grinding the plastic package layer to expose the previously manufactured bump; and finally, carrying out back surface processing; or performing a back surface manufacturing process firstly, and then grinding the plastic package layer to expose the previously manufactured bumps. According to the method, temporary bonding is not needed, and the problems of wafer breakage and the like caused by temporary bonding stripping are eliminated; and meanwhile, the plastic packaging layer is always on the front surface of the wafer, so that the wafer is always a thick wafer in the back surface processing process, and the problems of wafer breakage and the like can be reduced.

Description

technical field [0001] The invention relates to the technical field of transistors, in particular to a preparation method of an insulated gate bipolar transistor. Background technique [0002] IGBT (Insulated Gate Bipolar Transistor), Insulated Gate Bipolar Transistor, is a composite fully-controlled voltage-driven power semiconductor device composed of BJT (Bipolar Transistor) and MOS (Insulated Gate Field Effect Transistor), with MOSFET The advantages of high input impedance and low conduction voltage drop of GTR. The saturation voltage of GTR is low, the carrying current density is large, but the driving current is large; the driving power of MOSFET is small, the switching speed is fast, but the conduction voltage drop is large, and the current carrying density is small. The IGBT combines the advantages of the above two devices, with low driving power and low saturation voltage. It is very suitable for the conversion system with a DC voltage of 600V and above, such as A...

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Problems solved by technology

[0006] The Taiko process has the following disadvantages: the Taiko process only uses a thick edge with a width of 2-4mm to support the wafer without warping, but the wafer itself is still a thin sheet, and it is still easy to break in subsequent processing; Taiko thinning equipment and subsequent equipment for cutting thick edges very expensive

[0008] The disadvantages of the temporary bonding process are: it is difficult to peel off the thin IGBT wafer from the support wafer after the back is processed, and it is easy to break; bonding equipment, stripping equipment, and glue or tape for bonding are expensive

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