Formation method of fin field-effect transistor

Abstract

A formation method of a fin field-effect transistor comprises the steps of forming lining oxide layers on a surface, a surface of a side wall of a first fin part and a surface of a side wall of a second fin part; forming an insulation blocking layer on a surface of the lining oxide layer on a first region; depositing a precursor material layer on a surface of the insulation blocking layer and a surface of the lining oxide layer on a second region; performing curing and annealing on the precursor material layer under a H2O-containing atmosphere, and converting the precursor material layer to an insulation layer, wherein during the curing and annealing process, the side wall of the first fin part is oxidized to form a first oxide layer, the side wall of the second fin part is oxidized to form a second oxide layer, and the thickness of the first oxide layer is smaller than the thickness of the second oxide layer; and removing the insulation layer in a partial thickness to form an isolation layer, and also removing the lining oxide layer, the insulation blocking layer, the first oxide layer and the second oxide layer which are higher than the top of the isolation layer. After the isolation layer is formed, the critical dimension of the first fin part is larger than the critical dimension of the second fin part, and the process is simple in step.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for forming a fin field effect transistor. Background technique [0002] With the continuous development of semiconductor process technology, the development trend of semiconductor process nodes following Moore's Law continues to decrease. In order to adapt to the reduction of process nodes, the channel length of MOSFET field effect transistors has to be continuously shortened. The shortening of the channel length has the advantages of increasing the die density of the chip and increasing the switching speed of the MOSFET field effect tube. [0003] However, as the channel length of the device is shortened, the distance between the source and the drain of the device is also shortened, so that the control ability of the gate to the channel becomes worse, and the gate voltage pinches off the channel. The difficulty is also increasing, making the pheno...

AI Technical Summary

Problems solved by technology

[0005] However, in the prior art, when the fins in the fin field effect transistors to be formed have different critical dimensions (CD, Critical Dimension), they are usually formed by a more complicated process. Therefore, it is urgent to provide a new A method for forming a fin field effect transistor, forming fins with different critical dimensions, and the process steps are simple

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