Method for forming transistor and method for forming semiconductor device

Abstract

The invention discloses a method for forming a transistor and a method for forming a semiconductor device. The method for forming the transistor comprises the following steps: providing a semiconductor substrate; forming a plurality of shallow-groove isolation structures in the semiconductor substrate, wherein the upper surface of each shallow-groove isolation structure is lower than that of the semiconductor substrate and the difference is greater than a set threshold value, and the side wall, of the semiconductor substrate, adjacent to the shallow-groove isolation structure is an inclined surface; forming a gate structure on the semiconductor substrate, wherein the gate structure covers the part, of inclined surface, in the width direction; using the gate structure as a mask to perform lightly-doped ion implantation in the parts, of the semiconductor substrate, on both sides of the gate structure and in the direction perpendicular to the upper surface of the semiconductor substrate, and perform lightly-doped ion implantation on the inclined surface, of the semiconductor substrate, covered by the gate structure in the direction of which the included angle with the upper surface of the semiconductor substrate is a set angle, so as to form a lightly-doped region. The invention can increase the effective width of the channel region of the transistor, and improve the performance of the device.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for forming a transistor and a method for forming a semiconductor device. Background technique [0002] With the rapid development of semiconductor manufacturing technology, semiconductor devices are developing towards higher component density and higher integration. Transistors, as the most basic semiconductor devices, are currently being widely used. Therefore, with the improvement of component density and integration of semiconductor devices, the size of the channel region of transistors is also getting smaller and smaller. [0003] Prior art methods for forming transistors include: [0004] A semiconductor substrate is provided, and the semiconductor substrate includes a plurality of shallow trench isolation structures; [0005] forming a gate structure on a semiconductor substrate; [0006] Using the gate structure as a mask, lightly doped ion...

AI Technical Summary

Problems solved by technology

When the length of the channel region of the transistor is constant, the smaller the width of the transistor, the smaller the driving current of the transistor, and the worse the performance of the transistor

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