Ge channel metal-oxide-semiconductor field-effect transistor with InAlP cover layer

Abstract

The invention provides a Ge channel metal-oxide-semiconductor field-effect transistor (MOSFET) with an InAlP cover layer. The MOSFET (10) is characterized in that a Ge channel (101) is positioned on a substrate (108), the InAlP cover layer (102) is arranged above the Ge channel, an insulating dielectric film (103) is positioned between the InAlP cover layer and a gate (106), an insulating gap wall (107) separates the gate and a source / drain area (104 and 105), and an insulating gap wall separates the InAlP cover layer and the source / drain area. InAlP has a larger forbidden bandwidth than Ge, and effective band offset is formed at the positions of a conduction band and an interface valence band of Ge and InAlP so as to limit a conducting charge carrier in a Ge channel layer.

Description

technical field [0001] The invention relates to a Ge channel MOSFET (Metal-oxide-semiconductor Field-effect Transistor: metal-oxide-semiconductor field-effect transistor) with an InAlP capping layer. Background technique [0002] With the in-depth development of integrated circuit technology, in order to improve chip performance and integration, the channel length of Metal-oxide-semiconductor Field-effect Transistor (MOSFET) is continuously shortened, and the device performance is also continuously improved. According to the forecast of the International Technology Roadmap for Semiconductors (ITRS), when the integrated circuit technology node reaches below 10 nanometers, the strained Si material can no longer meet the needs, and the high carrier mobility material MOSFET must be introduced to improve the chip. performance. Single crystal Ge materials have high electron and hole mobility (electron: 3900cm 2 / V·s; Hole: 1900cm 2 / V s), is a popular material for realizing hig...

AI Technical Summary

Problems solved by technology

However, for n-type Ge channel MOSFET devices, the method invented by the predecessors cannot achieve high effective electron mobility.

Regardless of the GeO2, Si passivation layer or GeON layer, the interface with the Ge channel has too small a band step on the conduction band to effectively isolate the Ge channel from the insulating dielectric film.

In this way, the electrons in the Ge channel are always scattered by the defect state in the insulating dielectric film or the interface state at the interface, so the effective mobility of the electron is very low.

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