Semiconductor device

Abstract

A semiconductor device comprises n-type and p-type semiconductor devices formed on the substrate, the n-type device including an n-channel region formed on the substrate, n-type source and drain regions formed opposite to each other interposing the n-channel region therebetween, a first gate insulator formed on the n-channel region, and a first gate electrode formed on the first gate insulator and including a compound of a metal M and a first group-IV elements Si1−a Gea (0≦a≦1), the p-type device including a p-channel region formed on the substrate, p-type source and drain regions formed opposite to each other interposing the p-channel region therebetween, a second gate insulator formed on the p-channel region, and a second gate electrode formed on the second gate insulator, and including a compound of the metal M and a second group-IV element Si1−c Gec (0≦c≦1, a≠c).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2003-407658, filed Dec. 5, 2003, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to a semiconductor device including a field effect transistor. [0004] 2. Description of the Related Art [0005] In order to achieve high functionality of integrated circuits, elements forming the integrated circuits, that is, MISFETs (Metal-Insulator-Semiconductor Field Effect Transistors) and CMISFETs (Complementary-MISFETs) need to have high performance. The MISFET is a metal-insulator-semiconductor field effect transistor and the CMISFET is a complementary metal-insulator-semiconductor field effect transistor. Basically, high performance of these elements has been achieved according to scaling law. However, various problems have rece...

AI Technical Summary

Problems solved by technology

However, various problems have recently arisen due to the limitations of material properties.

To describe one of the foregoing problems, there is a problem that it is difficult to control the threshold voltage of a MISFET.

However, if the foregoing method is employed, carrier mobility is reduced; for this reason, the on / off characteristic of the MISFET is degraded.

However, the threshold voltage control for the MISFET is not achieved according to the method of controlling the impurity concentration in channel only.

However, if quite different gate electrode materials are used, the manufacturing method becomes complicated, and the cost increases.

However, the foregoing methods do not meet the requirements described above.

However, heat resistance is low, and the work function irregularly varies by heat treatment of about 500° C. or more at least.

Thus, the correlation is thermally unstable.

As a result, there is a problem that the on / off characteristic of the MISFET is degraded.

However, the variable range of the work function is insufficient to obtain a sufficiently low threshold voltage in a bulk MISFET device, which is not the fully-depleted MISFET device.

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