Trench power device structure and method of making the same

Abstract

The invention discloses a groove-power device structure and a manufacturing method thereof. The groove-power device structure comprises an active area and a terminal, wherein the active area and the terminal are both positioned on a substrate, the active area comprises a body area, a source area, a contact hole, an active-area groove, a first isolating layer and a source-electrode metal layer, the terminal comprises a terminal groove, a second isolating layer, a blocking layer and a grid-electrode metal layer, the contact hole is positioned between the body area and the source area, the first isolating layer is positioned above the active-area groove, the source-electrode metal layer is positioned above the body area, the source area, the first isolating layer and one part of the second isolating layer, the second isolating layer is positioned above the terminal groove, the blocking layer is positioned at the inside and the periphery of the terminal groove, and the grid-electrode metal layer is positioned above the other part of the second isolating layer. The groove-power device structure has the advantages of simple process, low cost, small occupied size, wide voltage-resisting adapting range, small electricity leakage and stable performance.

Description

technical field [0001] The invention relates to a semiconductor device structure and a manufacturing method thereof, in particular to a trench power device structure and a manufacturing method thereof. Background technique [0002] Metal Oxide Semiconductor Field Effect Transistor (MOSFET), Insulated Gate Bipolar Transistor (IGBT) and Super Barrier Diode (SBD) are some of the most important power devices. They are used in various fields of industrial electronics, home appliances and consumer electronics. They are inseparable from switching power supply circuits, rectifier circuits and drive circuits. Power devices require a large forward current and a large reverse voltage. Since the invention of power devices, improving their reverse withstand voltage capability has become an important issue. [0003] The withstand voltage capability of a power device consists of two parts: one is the withstand voltage of the active area, and the other is the withstand voltage of the ter...

AI Technical Summary

Problems solved by technology

figure 2 A pressure-dividing ring structure is given. The basic idea of ​​the pressure-dividing ring structure is to add one or more P regions at the terminal to extend the second equipotential surface 21, increase the radius of curvature of the equipotential surface, and disperse the electric field to achieve the purpose of improving the withstand voltage , but its shortcomings are also obvious, mainly in the following points: First, the process is more complicated and the cost is higher, at least five photolithography plates are required to produce a complete MOSFET or IGBT; second, the occupied size is large, such as making a 30V devices require a terminal size of more than 40um; third, the size needs to be adjusted according to the withstand voltage. For example, a 30V device requires a terminal size of 40um, while a 1200V device requires a terminal size of more than 400um; fourth, the leakage current is large; Affected by the external environment, changes in the external environment will cause changes in device performance, so there is no way to guarantee the consistency and stability of device performance

Images