Method for manufacturing trench gate type IGBT (insulated gate bipolar transistor) chip

Abstract

The invention discloses a method for manufacturing a trench gate type IGBT (insulated gate bipolar transistor) chip, which comprises the following steps: selecting two N-shaped semiconductor substrates, and carrying out oxidation or deposition on one of the substrates, so that insulating materials including silicon oxides or nitric oxides are formed on the surface of the substrate; carrying out photoetching and etching on the insulating materials on the surface of the substrate so as to form a dielectric buried layer; carrying out photoetching and etching on the other substrates so as to form a figure coincided with the concave-convex surface of the dielectric buried layer; carrying out concave-convex surface butt-joint on the dielectric buried layer and the figure, and bonding the two substrates together at high temperature; according to voltage-withstanding requirements and machining allowances, respectively carrying out thinning processing on the two substrates, and controlling the dielectric buried layer at a design depth, so that a chip manufacturing intermediate is formed; and completing the manufacturing process of a trench gate type IGBT chip. According to the invention, the drop voltage of the chip is reduced, a compromising relation with shut-off loss is optimized, and the lower power consumption is realized, thereby improving the power density, operating junction temperature and reliability of the IGBT chip.

Description

technical field [0001] The invention relates to a semiconductor IGBT (Insulted Gate Bipolar Transistor, insulated gate bipolar transistor) chip structure, in particular to a trench gate IGBT chip structure with double hole blocking effect. Background technique [0002] Insulated gate bipolar transistor (IGBT) has the characteristics of on-state voltage drop, large current capacity, high input impedance, fast response and simple control, and is widely used in industry, information, new energy, medicine, transportation, military and aviation fields . In order to reduce the turn-on voltage drop of the IGBT, people use a trench gate structure to change the channel from horizontal to vertical, eliminating the influence of RJFET in the on-resistance. At the same time, the cell size is reduced, the cell density is greatly increased, the total channel width of each chip is increased, and the channel resistance is reduced. On the other hand, since the polysilicon gate area increase...

AI Technical Summary

Problems solved by technology

[0006] The various technologies mentioned above have enhanced the conductance modulation effect of the IGBT to a certain extent, thereby reducing the conduction voltage drop, but these solutions only have a single hole blocking effect (only have a barrier blocking effect or only have a Physical blocking effect)

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