InP substrate MOSCAP structure and manufacturing method thereof

Abstract

The invention discloses an InP substrate MOSCAP structure and a manufacturing method thereof. The method includes the steps that S1, an Al2O3 gate dielectric (102) is deposited on an InP substrate; S2, N2 plasma treatment is conducted on the surface of the Al2O3 gate dielectric to form an AlON passivation layer (103); S3, a high-K gate dielectric (104) is deposited on the AlON passivation layer; S4, a metal gate structure (105) is formed on the high-K gate dielectric. The AlON passivation layer is formed by conducting N2 plasma treatment on the surface of the Al2O3 gate dielectric, and the high-K gate dielectric grows on the AlON passivation layer, so that defects in the Al2O3 gate dielectric are effectively repaired, the quality of the gate dielectric is greatly improved, EOT is reduced while grid electrode electric leakage is reduced, device reliability is improved, and electrical properties of III-V semiconductors (MOS) are greatly improved.

Description

technical field [0001] The invention relates to the technical field of semiconductor devices, in particular to a structure of an InP substrate MOSCAP and a preparation method thereof. Background technique [0002] As the feature size of complementary metal-oxide-semiconductor (CMOS) devices continues to shrink, the development of Si MOS devices is approaching its physical limit. III-V compound semiconductor materials with high mobility are considered as one of the alternatives to silicon-based CMOS channel materials. [0003] As one of the most promising III-V compound semiconductors, InP has high electron mobility (5400cm 2 / Vs), however, directly growing a high-K gate dielectric material on the InP surface will lead to an excessively high interface state density. Improving the quality of the High-K / InP interface, reducing EOT while reducing leakage and improving the reliability of the gate dielectric are issues that must be studied. About N 2 Plasma-related reports are...

AI Technical Summary

Problems solved by technology

[0005] The present invention proposes a structure and preparation method of an InP substrate MOSCAP, the main purpose of which is to solve the problem of high interface state density caused by directly growing a high-K gate dielectric material on the InP surface, and at the same time, leakage under the condition of reduced EOT Excessively large, and defects in the reliability of the gate dielectric

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